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Sample records for a1c fasting plasma

  1. Comparison of the Current Diagnostic Criterion of HbA1c with Fasting and 2-Hour Plasma Glucose Concentration

    PubMed Central

    Karnchanasorn, Rudruidee; Huang, Jean; Feng, Wei; Chuang, Lee-Ming

    2016-01-01

    To determine the effectiveness of hemoglobin A1c (HbA1c) ≥ 6.5% in diagnosing diabetes compared to fasting plasma glucose (FPG) ≥ 126 mg/dL and 2-hour plasma glucose (2hPG) ≥ 200 mg/dL in a previously undiagnosed diabetic cohort, we included 5,764 adult subjects without established diabetes for whom HbA1c, FPG, 2hPG, and BMI measurements were collected. Compared to the FPG criterion, the sensitivity of HbA1c ≥ 6.5% was only 43.3% (106 subjects). Compared to the 2hPG criterion, the sensitivity of HbA1c ≥ 6.5% was only 28.1% (110 subjects). Patients who were diabetic using 2hPG criterion but had HbA1c < 6.5% were more likely to be older (64 ± 15 versus 60 ± 15 years old, P = 0.01, mean ± STD), female (53.2% versus 38.2%, P = 0.008), leaner (29.7 ± 6.1 versus 33.0 ± 6.6 kg/m2, P = 0.000005), and less likely to be current smokers (18.1% versus 29.1%, P = 0.02) as compared to those with HbA1c ≥ 6.5%. The diagnostic agreement in the clinical setting revealed the current HbA1c ≥ 6.5% is less likely to detect diabetes than those defined by FPG and 2hPG. HbA1c ≥ 6.5% detects less than 50% of diabetic patients defined by FPG and less than 30% of diabetic patients defined by 2hPG. When the diagnosis of diabetes is in doubt by HbA1c, FPG and/or 2hPG should be obtained. PMID:27597979

  2. Are the Same Clinical Risk Factors Relevant for Incident Diabetes Defined by Treatment, Fasting Plasma Glucose, and HbA1c?

    PubMed Central

    Balkau, Beverley; Soulimane, Soraya; Lange, Céline; Gautier, Alain; Tichet, Jean; Vol, Sylviane

    2011-01-01

    OBJECTIVE To compare incidences and risk factors for diabetes using seven definitions, with combinations of pharmacological treatment, fasting plasma glucose (FPG) ≥7.0 mmol/L, and HbA1c ≥6.5%. RESEARCH DESIGN AND METHODS Participants aged 30–65 years from the Data from an Epidemiological Study on the Insulin Resistance Syndrome (DESIR) cohort were followed for 9 years. RESULTS More men had incident diabetes as defined by FPG ≥7.0 mmol/L and/or treatment than by HbA1c ≥6.5% and/or treatment: 7.5% (140/1,867) and 5.3% (99/1,874), respectively (P < 0.009); for women incidences were similar: 3.2% (63/1,958) and 3.4% (66/1,954). Known risk factors predicted diabetes for almost all definitions. Among those with incident diabetes by FPG alone versus HbA1c alone, there were more men (78 vs. 35%), case patients were 8 years younger, and fewer were alcohol abstainers (12 vs. 35%) (all P < 0.005). A diabetes risk score discriminated well between those with and without incident diabetes for all definitions. CONCLUSIONS In men, FPG definitions yielded more incident cases of diabetes than HbA1c definitions, in contrast with women. An FPG-derived risk score remained relevant for HbA1c-defined diabetes. PMID:21346181

  3. Combined use of fasting plasma glucose and glycated hemoglobin A1c in a stepwise fashion to detect undiagnosed diabetes mellitus.

    PubMed

    Nakagami, Tomoko; Tominaga, Makoto; Nishimura, Rimei; Daimon, Makoto; Oizumi, Toshihide; Yoshiike, Nobuo; Tajima, Naoko

    2007-09-01

    Type 2 diabetes mellitus (DM) is a common and serious condition related with considerable morbidity. Screening for DM is one strategy for reducing this burden. In Japan National Diabetes Screening Program (JNDSP) guideline, the combined use of fasting plasma glucose (FPG) and glycated hemoglobin A1c (HbA1c) in a stepwise fashion has been recommended to identify the group of people needing life-style counseling or medical care. However, the efficacy of this program has not been fully evaluated, as an oral glucose tolerance test (OGTT) is not mandatory in the guideline. The aim of this study was to assess the validity of the screening test scenario, in which an OGTT would be applied to people needing life-style counseling or medical care on this guideline: FPG 110-125 mg/dl and HbA1c over 5.5%. Subjects were 1,726 inhabitants without a previous history of DM in the Funagata study, which is a population-based survey conducted in Yamagata prefecture to clarify the risk factors, related conditions, and consequences of DM. DM was diagnosed according to the 1999 World Health Organization criteria. The prevalence of undiagnosed DM was 6.6%. The tested screening scenario gave a sensitivity of 55.3%, a specificity of 98.4%, a positive predictive value of 70.8%, and a negative predictive value of 96.9% for undiagnosed DM. In conclusion, the screening test scenario, in which an OGTT would be followed by the combined use of FPG and HbA1c in a stepwise fashion according to the JNDSP guideline, was not effective in identifying people with undiagnosed DM.

  4. Modelling the Relative Contribution of Fasting and Post-Prandial Plasma Glucose to HbA1c in Healthy and Type 2 Diabetic Subjects

    ERIC Educational Resources Information Center

    Ollerton, Richard L.; Luzio, Steven D.; Owens, David R.

    2004-01-01

    Glycated haemoglobin (HbA1c) is regarded as the gold standard of glucose homeostasis assessment in diabetes. There has been much discussion in recent medical literature of experimental results concerning the relative contribution of fasting and post-prandial glucose levels to the value of HbA1c. A mathematical model of haemoglobin glycation is…

  5. C-Peptide Level in Fasting Plasma and Pooled Urine Predicts HbA1c after Hospitalization in Patients with Type 2 Diabetes Mellitus.

    PubMed

    Sonoda, Remi; Tanaka, Kentaro; Kikuchi, Takako; Onishi, Yukiko; Takao, Toshiko; Tahara, Tazu; Yoshida, Yoko; Suzawa, Naoki; Kawazu, Shoji; Iwamoto, Yasuhiko; Kushiyama, Akifumi

    2016-01-01

    In this study, we investigate how measures of insulin secretion and other clinical information affect long-term glycemic control in patients with type 2 diabetes mellitus. Between October 2012 and June 2014, we monitored 202 diabetes patients who were admitted to the hospital of Asahi Life Foundation for glycemic control, as well as for training and education in diabetes management. We measured glycated hemoglobin (HbA1c) six months after discharge to assess disease management. In univariate analysis, fasting plasma C-peptide immunoreactivity (F-CPR) and pooled urine CPR (U-CPR) were significantly associated with HbA1c, in contrast to ΔCPR and C-peptide index (CPI). This association was strongly independent of most other patient variables. In exploratory factor analysis, five underlying factors, namely insulin resistance, aging, sex differences, insulin secretion, and glycemic control, represented patient characteristics. In particular, insulin secretion and resistance strongly influenced F-CPR, while insulin secretion affected U-CPR. In conclusion, the data indicate that among patients with type 2 diabetes mellitus, F-CPR and U-CPR may predict improved glycemic control six months after hospitalization.

  6. Effect of dietary polyphenols from hop (Humulus lupulus L.) pomace on adipose tissue mass, fasting blood glucose, hemoglobin A1c, and plasma monocyte chemotactic protein-1 levels in OLETF rats.

    PubMed

    Yui, Kazuki; Uematsu, Hiroki; Muroi, Keisuke; Ishii, Kazuhiro; Baba, Minako; Osada, Kyoichi

    2013-01-01

    Hop (Humulus lupulus L.) pomace contains procyanidin-rich polyphenols, which are large oligomeric compounds of catechin. We studied the effect of high dose (1%) of dietary hop pomace polyphenols (HPs) in Otsuka Long-EvansTokushima Fatty (OLETF) rats, an animal model of type 2 diabetes. By 70 days, the rats fed HPs tended to have a lower body weight and reduced mesenteric white adipose tissue weight than the rats fed a control diet. Triglyceride levels in both plasma and liver tended to be lower in the HPs-fed group than in the control group. Dietary HPs substantially suppressed the activities of hepatic fatty acid synthetase, glucose-6-phosphate dehydrogenase, and malic enzyme, through the suppression of SREBP1c mRNA expression in OLETF rats. Moreover, in the HPs-fed group, monocyte chemotactic protein-1 (MCP-1) expression and fasting blood glucose levels at 40 days, and hemoglobin A1c (HbA1c) levels at 70 days were significantly lower than those in the control group. Thus, dietary HPs may exert an ameliorative function on hepatic fatty acid metabolism, glucose metabolism, and inflammatory response accompanying the increase of the adipose tissue mass in OLETF rats.

  7. Association between HbA1c and carotid atherosclerosis among elderly Koreans with normal fasting glucose

    PubMed Central

    Lee, Seung Won; Kim, Hyeon Chang; Lee, Yong-ho; Song, Bo Mi; Choi, Hansol; Park, Ji Hye; Rhee, Yumie; Kim, Chang Oh

    2017-01-01

    Aim We examined whether glycated haemoglobin (HbA1c) is associated to carotid atherosclerosis in an elderly Korean population with normal fasting glucose. Methods Using data from the Korean Urban Rural Elderly study, we conducted a cross-sectional analysis of 1,133 participants (335 men and 798 women) with a mean age of 71.8 years. All participants had fasting blood glucose less than 100mg/dL (5.6 mmol/L) and HbA1c level below 6.5% (48 mmol/mol). They were also free from a history of cardiovascular disease, known type 2 diabetes mellitus or use of anti-diabetes medications. Carotid atherosclerosis was assessed by intima-media thickness (IMT) using ultrasonography. The association between HbA1c and carotid IMT was investigated using multivariable linear regression analysis. Results HbA1c levels were independently and positively associated with carotid IMT (β = 0.020, p = 0.045) after adjusting for sex, age, body mass index, systolic blood pressure, diastolic blood pressure, triglyceride, LDL cholesterol, smoking and alcohol intake. However, fasting insulin and glucose levels were not associated with carotid IMT. Conclusion HbA1c levels were positively associated with carotid atherosclerosis, as assessed by carotid IMT, in an elderly population with normoglycemia. Our study suggested that higher HbA1c level is an effective and informative marker of carotid atherosclerosis in an elderly population. PMID:28178313

  8. Markers of glycemic control in the mouse: comparisons of 6-h- and overnight-fasted blood glucoses to Hb A1c.

    PubMed

    Han, Byoung Geun; Hao, Chuan-Ming; Tchekneva, Elena E; Wang, Ying-Ying; Lee, Chieh Allen; Ebrahim, Benyamin; Harris, Raymond C; Kern, Timothy S; Wasserman, David H; Breyer, Matthew D; Qi, Zhonghua

    2008-10-01

    The present studies examined the relationship between fasting blood glucose and Hb A(1c) in C57BL/6J, DBA/2J, and KK/HlJ mice with and without diabetes mellitus. Daily averaged blood glucose levels based on continuous glucose monitoring and effects of 6-h vs. overnight fasting on blood glucose were determined. Daily averaged blood glucose levels were highly correlated with Hb A(1c), as determined with a hand-held automated device using an immunodetection method. R(2) values were 0.90, 0.95, and 0.99 in KK/HIJ, C57BL/6J, and DBA/2J, respectively. Six-hour fasting blood glucose correlated more closely with the level of daily averaged blood glucose and with Hb A(1c) than did blood glucose following an overnight fast. To validate the immunoassay-determined Hb A(1c), we also measured total glycosylated hemoglobin using boronate HPLC. Hb A(1c) values correlated well with total glycosylated hemoglobin in all three strains but were relatively lower than total glycosylated hemoglobin in diabetic DBA/2J mice. These results show that 6-h fasting glucose provides a superior index of glycemic control and correlates more closely with Hb A(1c) than overnight-fasted blood glucose in these strains of mice.

  9. The effects of ginger on fasting blood sugar, hemoglobin a1c, apolipoprotein B, apolipoprotein a-I and malondialdehyde in type 2 diabetic patients.

    PubMed

    Khandouzi, Nafiseh; Shidfar, Farzad; Rajab, Asadollah; Rahideh, Tayebeh; Hosseini, Payam; Mir Taheri, Mohsen

    2015-01-01

    Diabetes mellitus is the most common endocrine disorder, causes many complications such as micro- and macro-vascular diseases. Anti-diabetic, hypolipidemic and anti-oxidative properties of ginger have been noticed in several researches. The present study was conducted to investigate the effects of ginger on fasting blood sugar, Hemoglobin A1c, apolipoprotein B, apolipoprotein A-I, and malondialdehyde in type 2 diabetic patients. In a randomized, double-blind, placebo-controlled, clinical trial, a total of 41 type 2 diabetic patients randomly were assigned to ginger or placebo groups (22 in ginger group and 19 in control group), received 2 g/day of ginger powder supplement or lactose as placebo for 12 weeks. The serum concentrations of fasting blood sugar, Hemoglobin A1c, apolipoprotein B, apolipoprotein A-I and malondialdehyde were analyzed before and after the intervention. Ginger supplementation significantly reduced the levels of fasting blood sugar, hemoglobin A1c, apolipoprotein B, apolipoprotein B/apolipoprotein A-I and malondialdehyde in ginger group in comparison to baseline, as well as control group, while it increased the level of apolipoprotein A-I (p<0.05). It seems that oral administration of ginger powder supplement can improves fasting blood sugar, hemoglobin A1c, apolipoprotein B, apolipoprotein A-I, apolipoprotein B/apolipoprotein A-I and malondialdehyde in type 2 diabetic patients. So it may have a role in alleviating the risk of some chronic complications of diabetes.

  10. The effect of nano-curcumin on HbA1c, fasting blood glucose, and lipid profile in diabetic subjects: a randomized clinical trial

    PubMed Central

    Rahimi, Hamid Reza; Mohammadpour, Amir Hooshang; Dastani, Mostafa; Jaafari, Mahmoud Reza; Abnous, Khalil; Ghayour Mobarhan, Majid; Kazemi Oskuee, Reza

    2016-01-01

    Objective: Diabetes mellitus is defined as a group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both or insulin resistance. Curcumin inhibits NF-κB signaling pathway. The aim of this study is evaluation of the effect of Nano-curcumin on HbA1C, fast blood glucose and lipid profile in diabetic patients. Materials and Methods: Seventy type-2 diabetic patients (fasting blood glucose (FBG) ≥ 126 mg/dL or 2-hr postprandial blood glucose ≥200 mg/dl) randomly receivedeither Curcumin (as nano-micelle 80 mg/day) or placebo for 3 months in a double blind randomized clinical trial. Fasting blood glucose, HbA1C, and lipids profile were checked before and after the intervention. Data analyses, including parametric and nonparametric tests were done using the SPSS 11.5 software. A p value < 0.05 was regarded as statistically significant. (RCT registration code: IRCT2013081114330N1) Results: Mean age, BMI, FBG, total cholesterol (TC), triglyceride (TG), LDL, HDL, HbA1c , and sex and had no significant difference at the baseline between the groups. In Nano-curcumin group, a significant decrease was found in HbA1C, FBG, TG, and BMI comparing results of each subject before and after the treatment (p<0.05). By comparing pre- and post-treatment values among the groups, HbA1c, eAG, LDL-C, and BMI variables showed significant differences (p<0.05). Conclusion: These findings suggest an HbA1c lowering effect for Nano-curcumin in type-2 diabetes; also, it is partially decrease in serum LDL-C and BMI. PMID:27761427

  11. A1C test

    MedlinePlus

    HbA1C test; Glycated hemoglobin test; Glycohemoglobin test; Hemoglobin A1C; Diabetes - A1C; Diabetic - A1C ... gov/pubmed/26696680 . Chernecky CC, Berger BJ. Glycosylated hemoglobin (GHb, glycohemoglobin, glycated hemoglobin, HbA1a, HbA1b, HbA1c - blood. ...

  12. Fast pulse nonthermal plasma reactor

    DOEpatents

    Rosocha, Louis A.

    2005-06-14

    A fast pulsed nonthermal plasma reactor includes a discharge cell and a charging assembly electrically connected thereto. The charging assembly provides plural high voltage pulses to the discharge cell. Each pulse has a rise time between one and ten nanoseconds and a duration of three to twenty nanoseconds. The pulses create nonthermal plasma discharge within the discharge cell. Accordingly, the nonthermal plasma discharge can be used to remove pollutants from gases or break the gases into smaller molecules so that they can be more efficiently combusted.

  13. Cardiometabolic Risk Profiles in Patients With Impaired Fasting Glucose and/or Hemoglobin A1c 5.7% to 6.4%: Evidence for a Gradient According to Diagnostic Criteria: The PREDAPS Study.

    PubMed

    Giráldez-García, Carolina; Sangrós, F Javier; Díaz-Redondo, Alicia; Franch-Nadal, Josep; Serrano, Rosario; Díez, Javier; Buil-Cosiales, Pilar; García-Soidán, F Javier; Artola, Sara; Ezkurra, Patxi; Carrillo, Lourdes; Millaruelo, J Manuel; Seguí, Mateu; Martínez-Candela, Juan; Muñoz, Pedro; Goday, Albert; Regidor, Enrique

    2015-11-01

    It has been suggested that the early detection of individuals with prediabetes can help prevent cardiovascular diseases. The purpose of the current study was to examine the cardiometabolic risk profile in patients with prediabetes according to fasting plasma glucose (FPG) and/or hemoglobin A1c (HbA1c) criteria.Cross-sectional analysis from the 2022 patients in the Cohort study in Primary Health Care on the Evolution of Patients with Prediabetes (PREDAPS Study) was developed. Four glycemic status groups were defined based on American Diabetes Association criteria. Information about cardiovascular risk factors-body mass index, waist circumference, blood pressure, cholesterol, triglycerides, uric acid, gamma-glutamyltransferase, glomerular filtration-and metabolic syndrome components were analyzed. Mean values of clinical and biochemical characteristics and frequencies of metabolic syndrome were estimated adjusting by age, sex, educational level, and family history of diabetes.A linear trend (P < 0.001) was observed in most of the cardiovascular risk factors and in all components of metabolic syndrome. Normoglycemic individuals had the best values, individuals with both criteria of prediabetes had the worst, and individuals with only one-HbA1c or FPG-criterion had an intermediate position. Metabolic syndrome was present in 15.0% (95% confidence interval: 12.6-17.4), 59.5% (54.0-64.9), 62.0% (56.0-68.0), and 76.2% (72.8-79.6) of individuals classified in normoglycemia, isolated HbA1c, isolated FPG, and both criteria groups, respectively.In conclusion, individuals with prediabetes, especially those with both criteria, have worse cardiometabolic risk profile than normoglycemic individuals. These results suggest the need to use both criteria in the clinical practice to identify those individuals with the highest cardiovascular risk, in order to offer them special attention with intensive lifestyle intervention programs.

  14. Cardiometabolic Risk Profiles in Patients With Impaired Fasting Glucose and/or Hemoglobin A1c 5.7% to 6.4%: Evidence for a Gradient According to Diagnostic Criteria

    PubMed Central

    Giráldez-García, Carolina; Sangrós, F. Javier; Díaz-Redondo, Alicia; Franch-Nadal, Josep; Serrano, Rosario; Díez, Javier; Buil-Cosiales, Pilar; García-Soidán, F. Javier; Artola, Sara; Ezkurra, Patxi; Carrillo, Lourdes; Millaruelo, J. Manuel; Seguí, Mateu; Martínez-Candela, Juan; Muñoz, Pedro; Goday, Albert; Regidor, Enrique

    2015-01-01

    Abstract It has been suggested that the early detection of individuals with prediabetes can help prevent cardiovascular diseases. The purpose of the current study was to examine the cardiometabolic risk profile in patients with prediabetes according to fasting plasma glucose (FPG) and/or hemoglobin A1c (HbA1c) criteria. Cross-sectional analysis from the 2022 patients in the Cohort study in Primary Health Care on the Evolution of Patients with Prediabetes (PREDAPS Study) was developed. Four glycemic status groups were defined based on American Diabetes Association criteria. Information about cardiovascular risk factors–body mass index, waist circumference, blood pressure, cholesterol, triglycerides, uric acid, gamma-glutamyltransferase, glomerular filtration–and metabolic syndrome components were analyzed. Mean values of clinical and biochemical characteristics and frequencies of metabolic syndrome were estimated adjusting by age, sex, educational level, and family history of diabetes. A linear trend (P < 0.001) was observed in most of the cardiovascular risk factors and in all components of metabolic syndrome. Normoglycemic individuals had the best values, individuals with both criteria of prediabetes had the worst, and individuals with only one–HbA1c or FPG–criterion had an intermediate position. Metabolic syndrome was present in 15.0% (95% confidence interval: 12.6–17.4), 59.5% (54.0–64.9), 62.0% (56.0–68.0), and 76.2% (72.8–79.6) of individuals classified in normoglycemia, isolated HbA1c, isolated FPG, and both criteria groups, respectively. In conclusion, individuals with prediabetes, especially those with both criteria, have worse cardiometabolic risk profile than normoglycemic individuals. These results suggest the need to use both criteria in the clinical practice to identify those individuals with the highest cardiovascular risk, in order to offer them special attention with intensive lifestyle intervention programs. PMID:26554799

  15. [Diagnostic value of fasting glucose, fructosamine, and glycated haemoglobin HbA(1c) with regard to ADA 1997 and who 1998 criteria for detecting diabetes and other glucose tolerance abnormalities].

    PubMed

    Gołembiewska, Edyta

    2004-01-01

    New diagnostic criteria for diabetes mellitus proposed by the American Diabetes Association in 1997 and the World Heath Organization Consultation Report in 1998 recommend lowering of the fasting plasma glucose (FPG) to 7.0 mmol/L. This change in the diagnostic FPG cut-off point was based on the results of well-documented epidemiological studies showing that increased risk of microangiopathy starts at values closer to 7.0 than 7.8 mmol/L used in the past. To facilitate the diagnosis, ADA Expert Committee recommends using FPG as the main diagnostic tool and eliminating OGTT from routine clinical practice. In contrast to ADA, WHO Consultation Group strongly recommended keeping OGTT in routine use. Due to the inconvenience, poor reproducibility, non-physiological character and labour-intensiveness of OGTT, an alternative test has been sought. The aim of this study was to determine whether fasting capillary glucose (FCG) along with fructosamine and glycated haemoglobin (HbA(1c)) perform better for the detection of glucose tolerance abnormalities than FCG alone. OGTT was performed in 1528 patients. Serum fructosamine was determined in 480 and glycated haemoglobin in 234 of these patients. To assess the value of FCG, fructosamine and glycated haemoglobin in predicting post-load glycaemia and detecting glucose tolerance abnormalities, multiple linear regression analysis and Receiver Operating Characteristics analysis were done. Fructosamine correlated stronger with 2h-postload glucose concentrations than with fasting glucose. HbA(1c) correlated stronger with FCG than with 2h-postload glucose. Combined use of fructosamine and FCG predicted 2h-postload glucose better than combined use of FCG and HbA(1c). Receiver Operating Characteristics curve analysis showed that FCG was the best criterion in discriminating diabetes. Combined use of FCG and fructosamine slightly improved the ability to discriminate glucose tolerance abnormalities from normal glucose tolerance. The

  16. A1C Test

    MedlinePlus

    ... eAG on their DiabetesPro web site . The NGSP web site also provides a calculator to convert hemoglobin A1c in SI units mmol/mol into percentage. ^ Back to top Is there anything else I should know? The A1c test will not reflect temporary, acute blood glucose increases ...

  17. A1C

    MedlinePlus

    A1C is a blood test for type 2 diabetes and prediabetes. It measures your average blood glucose, or blood sugar, level over the past 3 ... A1C alone or in combination with other diabetes tests to make a diagnosis. They also use the ...

  18. Hemoglobin A1c in predicting progression to diabetes.

    PubMed

    Nakagami, Tomoko; Tajima, Naoko; Oizumi, Toshihide; Karasawa, Shigeru; Wada, Kiriko; Kameda, Wataru; Susa, Shinji; Kato, Takeo; Daimon, Makoto

    2010-01-01

    The predictive value of hemoglobin A1c (HbA1c) in comparison to fasting plasma glucose (FPG) is evaluated for 5-year incident diabetes (DM), as HbA1c may be more practical than FPG in the screening for DM in the future. Of 1189 non-DM subjects aged 35-89 years old from the Funagata Study, 57 subjects (4.8%) had developed DM on the WHO criteria at 5-year follow-up. The odds ratio (95% confidence interval: CI) for a one standard deviation increase in FPG/HbA1c was 3.40 (2.44-4.74)/3.49 (2.42-5.02). The area under the receiver operating characteristic curve for FPG/HbA1c was 0.786 (95% CI: 0.719-0.853)/0.785 (0.714-0.855). The HbA1c corresponding to FPG 5.56 mmol/l was HbA1c 5.3%. There was no statistical difference in sensitivity between FPG 5.56 mmol/l and HbA1c 5.3% (61.4% vs. 56.1%), while specificity was higher in HbA1c 5.3% than FPG 5.56 mmol/l (87.8% vs. 82.5%, p-value<0.001). The fraction of incident case from those with baseline IGT was similar between the groups, however the fraction of people above the cut-off was significantly lower in HbA1c 5.3% than FPG 5.56 mmol/l (14.3% vs. 19.6%, p-value<0.001). HbA1c is similar to FPG to evaluate DM risk, and HbA1c could be practical and efficient to select subjects for intervention.

  19. Insufficient Sensitivity of Hemoglobin A1C (A1C) Determination in Diagnosis or Screening of Early Diabetic States

    PubMed Central

    Fajans, Stefan S.; Herman, William H.; Oral, Elif A.

    2010-01-01

    An International Expert Committee made recommendations for using the hemoglobin A1C (A1C) assay as the preferred method for diagnosis of diabetes in nonpregnant individuals. A concentration of ≥ 6.5% was considered as diagnostic. It is the aim of this study to compare the sensitivity of A1C with that of plasma glucose concentrations in subjects with early diabetes or IGT. We chose two groups of subjects who had A1C of ≤ 6.4%. The first group of 89 subjects had family histories of diabetes (MODY or T2DM) and had OGTT and A1C determinations. They included 36 subjects with diabetes or IGT and 53 with normal OGTT. The second group of 58 subjects was screened for diabetes in our Diabetes Clinic by FPG or 2HPG or OGTT and A1C and similar comparisons were made. Subjects with diabetes or IGT, including those with fasting hyperglycemia, had A1C ranging from 5.0 – 6.4%, mean 5.8%. The subjects with normal OGTT had A1C of 4.2 – 6.3%, mean 5.4% or 5.5% for the two groups. A1C may be in the normal range in subjects with diabetes or IGT, including those with fasting hyperglycemia. Approximately one third of subjects with early diabetes and IGT have A1C <5.7%, the cut-point that ADA recommends as indicating the onset of risk of developing diabetes in the future. The results of our study are similar to those obtained by a large Dutch epidemiological study. If our aim is to recognize early diabetic states to apply effective prophylactic procedures to prevent or delay progression to more severe diabetes, A1C is not sufficiently sensitive or reliable for diagnosis of diabetes or IGT. A combination of A1C and plasma glucose determinations, where necessary, are recommended for diagnosis or screening of diabetes or IGT. PMID:20723948

  20. The difference between oats and beta-glucan extract intake in the management of HbA1c, fasting glucose and insulin sensitivity: a meta-analysis of randomized controlled trials.

    PubMed

    He, Li-xia; Zhao, Jian; Huang, Yuan-sheng; Li, Yong

    2016-03-01

    Increasing oats and beta-glucan extract intake has been associated with improved glycemic control, which is associated with the reduction in the development of diabetes. This study aims to assess the different effects between oat (whole and bran) and beta-glucan extract intake on glycemic control and insulin sensitivity. PubMed, Embase, Medline, The Cochrane Library, CINAHL and Web of Science were searched up to February 2014. We included randomized controlled trials with interventions that lasted at least four weeks that compared oats and beta-glucan (extracted from oats or other sources) intake with a control. A total of 1351 articles were screened for eligibility, and relevant data were extracted from 18 studies (n = 1024). Oat product dose ranged from 20 g d(-1) to 136 g d(-1), and beta-glucan extract dose ranged from 3 g d(-1) to 10 g d(-1). Compared with the control, oat intake resulted in a greater decrease in fasting glucose and insulin of subjects (P < 0.05), but beta-glucan extract intake did not. Furthermore, oat intake resulted in a greater decrease in glycosylated hemoglobin (HbA1c) (P < 0.001, I(2) = 0%) and fasting glucose (P < 0.001, I(2) = 68%) after removing one study using a concentrate and a different design and fasting insulin of type 2 diabetes (T2D) (P < 0.001, I(2) = 0%). The intake of oats and beta-glucan extracted from oats were effective in decreasing fasting glucose (P = 0.007, I(2) = 91%) and fasting insulin of T2D (P < 0.001, I(2) = 0%) and tented to lower HbA1c (P = 0.09, I(2) = 92%). Higher consumption of whole oats and oat bran, but not oat or barley beta-glucan extracts, are associated with lower HbA1c, fasting glucose and fasting insulin of T2D, hyperlipidaemic and overweight subjects, especially people with T2D, which supports the need for clinical trials to evaluate the potential role of oats in approaching to the management of glycemic control and insulin sensitivity of diabetes or metabolic syndrome subjects.

  1. Fast wave evanescence in filamentary boundary plasmas

    SciTech Connect

    Myra, J. R.

    2014-02-15

    Radio frequency waves for heating and current drive of plasmas in tokamaks and other magnetic confinement devices must first traverse the scrape-off-layer (SOL) before they can be put to their intended use. The SOL plasma is strongly turbulent and intermittent in space and time. These turbulent properties of the SOL, which are not routinely taken into account in wave propagation codes, can have an important effect on the coupling of waves through an evanescent SOL or edge plasma region. The effective scale length for fast wave (FW) evanescence in the presence of short-scale field-aligned filamentary plasma turbulence is addressed in this paper. It is shown that although the FW wavelength or evanescent scale length is long compared with the dimensions of the turbulence, the FW does not simply average over the turbulent density; rather, the average is over the exponentiation rate. Implications for practical situations are discussed.

  2. Relationship between Hb and HbA1c in Japanese adults: an analysis of the 2009 Japan Society of Ningen Dock database.

    PubMed

    Takahashi, Eiko; Moriyama, Kengo; Yamakado, Minoru

    2014-06-01

    We investigated the effect of Hb on HbA1c levels in 265,427 Japanese individuals. The divergence between fasting plasma glucose (FPG) and HbA1c levels increased with lower Hb, resulting in HbA1c levels that were higher in relation to than the FPG levels. Similarly, the correlation between FPG and HbA1c levels, stratified by Hb, weakened as Hb decreased.

  3. Evaluation of Hemoglobin A1c Criteria to Assess Preoperative Diabetes Risk in Cardiac Surgery Patients

    PubMed Central

    Saberi, Sima; Zrull, Christina A.; Patil, Preethi V.; Jha, Leena; Kling-Colson, Susan C.; Gandia, Kenia G.; DuBois, Elizabeth C.; Plunkett, Cynthia D.; Bodnar, Tim W.; Pop-Busui, Rodica

    2011-01-01

    Abstract Objective Hemoglobin A1c (A1C) has recently been recommended for diagnosing diabetes mellitus and diabetes risk (prediabetes). Its performance compared with fasting plasma glucose (FPG) and 2-h post-glucose load (2HPG) is not well delineated. We compared the performance of A1C with that of FPG and 2HPG in preoperative cardiac surgery patients. Methods Data from 92 patients without a history of diabetes were analyzed. Patients were classified with diabetes or prediabetes using established cutoffs for FPG, 2HPG, and A1C. Sensitivity and specificity of the new A1C criteria were evaluated. Results All patients diagnosed with diabetes by A1C also had impaired fasting glucose, impaired glucose tolerance, or diabetes by other criteria. Using FPG as the reference, sensitivity and specificity of A1C for diagnosing diabetes were 50% and 96%, and using 2HPG as the reference they were 25% and 95%. Sensitivity and specificity for identifying prediabetes with FPG as the reference were 51% and 51%, respectively, and with 2HPG were 53% and 51%, respectively. One-third each of patients with prediabetes was identified using FPG, A1C, or both. When testing A1C and FPG concurrently, the sensitivity of diagnosing dysglycemia increased to 93% stipulating one or both tests are abnormal; specificity increased to 100% if both tests were required to be abnormal. Conclusions In patients before cardiac surgery, A1C criteria identified the largest number of patients with diabetes and prediabetes. For diagnosing prediabetes, A1C and FPG were discordant and characterized different groups of patients, therefore altering the distribution of diabetes risk. Simultaneous measurement of FGP and A1C may be a more sensitive and specific tool for identifying high-risk individuals with diabetes and prediabetes. PMID:21854260

  4. Fast ion beam-plasma interaction system.

    PubMed

    Breun, R A; Ferron, J R

    1979-07-01

    A device has been constructed for the study of the interaction between a fast ion beam and a target plasma of separately controllable parameters. The beam of either hydrogen or helium ions has an energy of 1-4 keV and a total current of 0.5-2 A. The beam energy and beam current can be varied separately. The ion source plasma is created by a pulsed (0.2-10-ms pulse length) discharge in neutral gas at up to 3 x 10(-3) Torr. The neutrals are pulsed into the source chamber, allowing the neutral pressure in the target region to remain less than 5 x 10(-5) Torr at a 2-Hz repetition rate. The creation of the source plasma can be described by a simple set of equations which predict optimum source design parameters. The target plasma is also produced by a pulsed discharge. Between the target and source chambers the beam is neutralized by electrons drawn from a set of hot filaments. Currently under study is an unstable wave in a field-free plasma excited when the beam velocity is nearly equal to the target electron thermal velocity (v(beam) approximately 3.5 x 10(7) cm/s, Te = 0.5 eV).

  5. Laser–plasma interactions for fast ignition

    SciTech Connect

    Kemp, A. J.; Fiuza, F.; Debayle, A.; Johzaki, T.; Mori, W. B.; Patel, P. K.; Sentoku, Y.; Silva, L. O.

    2014-04-17

    In the electron-driven fast-ignition approach to inertial confinement fusion, petawatt laser pulses are required to generate MeV electrons that deposit several tens of kilojoules in the compressed core of an imploded DT shell. We review recent progress in the understanding of intense laser- plasma interactions (LPI) relevant to fast ignition. Increases in computational and modeling capabilities, as well as algorithmic developments have led to enhancement in our ability to perform multidimensional particle-in-cell (PIC) simulations of LPI at relevant scales. We discuss the physics of the interaction in terms of laser absorption fraction, the laser-generated electron spectra, divergence, and their temporal evolution. Scaling with irradiation conditions such as laser intensity, f-number and wavelength are considered, as well as the dependence on plasma parameters. Different numerical modeling approaches and configurations are addressed, providing an overview of the modeling capabilities and limitations. In addition, we discuss the comparison of simulation results with experimental observables. In particular, we address the question of surrogacy of today's experiments for the full-scale fast ignition problem.

  6. Laser–plasma interactions for fast ignition

    DOE PAGES

    Kemp, A. J.; Fiuza, F.; Debayle, A.; ...

    2014-04-17

    In the electron-driven fast-ignition approach to inertial confinement fusion, petawatt laser pulses are required to generate MeV electrons that deposit several tens of kilojoules in the compressed core of an imploded DT shell. We review recent progress in the understanding of intense laser- plasma interactions (LPI) relevant to fast ignition. Increases in computational and modeling capabilities, as well as algorithmic developments have led to enhancement in our ability to perform multidimensional particle-in-cell (PIC) simulations of LPI at relevant scales. We discuss the physics of the interaction in terms of laser absorption fraction, the laser-generated electron spectra, divergence, and their temporalmore » evolution. Scaling with irradiation conditions such as laser intensity, f-number and wavelength are considered, as well as the dependence on plasma parameters. Different numerical modeling approaches and configurations are addressed, providing an overview of the modeling capabilities and limitations. In addition, we discuss the comparison of simulation results with experimental observables. In particular, we address the question of surrogacy of today's experiments for the full-scale fast ignition problem.« less

  7. Fast temperature relaxation model in dense plasmas

    NASA Astrophysics Data System (ADS)

    Faussurier, Gérald; Blancard, Christophe

    2017-01-01

    We present a fast model to calculate the temperature-relaxation rates in dense plasmas. The electron-ion interaction-potential is calculated by combining a Yukawa approach and a finite-temperature Thomas-Fermi model. We include the internal energy as well as the excess energy of ions using the QEOS model. Comparisons with molecular dynamics simulations and calculations based on an average-atom model are presented. This approach allows the study of the temperature relaxation in a two-temperature electron-ion system in warm and hot dense matter.

  8. Is There a Role for HbA1c in Pregnancy?

    PubMed

    Hughes, Ruth C E; Rowan, Janet; Florkowski, Chris M

    2016-01-01

    Outside pregnancy, HbA1c analysis is used for monitoring, screening for and diagnosing diabetes and prediabetes. During pregnancy, the role for HbA1c analysis is not yet established. Physiological changes lower HbA1c levels, and pregnancy-specific reference ranges may need to be recognised. Other factors that influence HbA1c are also important to consider, particularly since emerging data suggest that, in early pregnancy, HbA1c elevations close to the reference range may both identify women with underlying hyperglycaemia and be associated with adverse pregnancy outcomes. In later pregnancy, HbA1c analysis is less useful than an oral glucose tolerance test (OGTT) at detecting gestational diabetes. Postpartum, HbA1c analysis detects fewer women with abnormal glucose tolerance than an OGTT, but the ease of testing may improve follow-up rates and combining HbA1c analysis with fasting plasma glucose or waist circumference may improve detection rates. This article discusses the relevance of HbA1c testing at different stages of pregnancy.

  9. Citrate in plasma and urine during total fasting.

    PubMed

    Nielsen, T T; Sørensen, N S

    1979-01-01

    Plasma citrate was determined in 12 obese subjects who underwent total fasting for 10 days. Mean plasma citrate concentration rose significantly from 128 before to 205 micro mol/1 on the 10th day of fasting. Plasma citrate rose continuously during fasting in seven subjects in whom daily determinations were carried out. The 24-hour urinary citrate excretion was followed in six subjects. A significant decrease was found from 2.91 mmol/24 h in the prefasting state to 0.25 mmol/24 h at the end of the fast. Intravenous glucose tolerance test were performed before and on the 10th day of fasting. Kivgtt decreased significantly and was inversely related to plasma citrate concentration on the 10th day of fasting. The results agree well with the concept that an increased citrate level of tissues is of regulatory importance for the decreased glucose utilization during fasting in man.

  10. Fast Camera Movies of NSTX Plasmas

    DOE Data Explorer

    Maqueda, Ricky; Wurden, Glenn

    The National Spherical Torus Experiment (NSTX) is an innovative magnetic fusion device that is being used to study the physics principles of spherically shaped plasmas -- hot ionized gases in which nuclear fusion will occur under the appropriate conditions of temperature, density, and confinement in a magnetic field. Fusion is the energy source of the Sun and all the stars. Scientists believe it can provide an inexhaustible, safe, and environmentally attractive source. NSTX was constructed by the Princeton Plasma Physics Laboratory (PPPL) in conjunction with Oak Ridge National Laboratory, Columbia University, and the University of Washington Seattle. The original TIF images recorded by the KODAK digital camera (i.e., "raw data") are available, using the contact information given on the same web page that provides access to these fast camera movies. MPEG clips are organized under the following headings: • Gas Puff Imaging (GPI) diagnostic • GPI experiments • H-modes (longer) • H-modes (short) • Coaxial Helicity Injection experiments More than 100 MPEGS dating back to 1999 are available for public access.

  11. Fast Plasma Investigation for Magnetospheric Multiscale

    NASA Astrophysics Data System (ADS)

    Pollock, C.; Moore, T.; Jacques, A.; Burch, J.; Gliese, U.; Saito, Y.; Omoto, T.; Avanov, L.; Barrie, A.; Coffey, V.; Dorelli, J.; Gershman, D.; Giles, B.; Rosnack, T.; Salo, C.; Yokota, S.; Adrian, M.; Aoustin, C.; Auletti, C.; Aung, S.; Bigio, V.; Cao, N.; Chandler, M.; Chornay, D.; Christian, K.; Clark, G.; Collinson, G.; Corris, T.; De Los Santos, A.; Devlin, R.; Diaz, T.; Dickerson, T.; Dickson, C.; Diekmann, A.; Diggs, F.; Duncan, C.; Figueroa-Vinas, A.; Firman, C.; Freeman, M.; Galassi, N.; Garcia, K.; Goodhart, G.; Guererro, D.; Hageman, J.; Hanley, J.; Hemminger, E.; Holland, M.; Hutchins, M.; James, T.; Jones, W.; Kreisler, S.; Kujawski, J.; Lavu, V.; Lobell, J.; LeCompte, E.; Lukemire, A.; MacDonald, E.; Mariano, A.; Mukai, T.; Narayanan, K.; Nguyan, Q.; Onizuka, M.; Paterson, W.; Persyn, S.; Piepgrass, B.; Cheney, F.; Rager, A.; Raghuram, T.; Ramil, A.; Reichenthal, L.; Rodriguez, H.; Rouzaud, J.; Rucker, A.; Saito, Y.; Samara, M.; Sauvaud, J.-A.; Schuster, D.; Shappirio, M.; Shelton, K.; Sher, D.; Smith, D.; Smith, K.; Smith, S.; Steinfeld, D.; Szymkiewicz, R.; Tanimoto, K.; Taylor, J.; Tucker, C.; Tull, K.; Uhl, A.; Vloet, J.; Walpole, P.; Weidner, S.; White, D.; Winkert, G.; Yeh, P.-S.; Zeuch, M.

    2016-03-01

    The Fast Plasma Investigation (FPI) was developed for flight on the Magnetospheric Multiscale (MMS) mission to measure the differential directional flux of magnetospheric electrons and ions with unprecedented time resolution to resolve kinetic-scale plasma dynamics. This increased resolution has been accomplished by placing four dual 180-degree top hat spectrometers for electrons and four dual 180-degree top hat spectrometers for ions around the periphery of each of four MMS spacecraft. Using electrostatic field-of-view deflection, the eight spectrometers for each species together provide 4pi-sr field-of-view with, at worst, 11.25-degree sample spacing. Energy/charge sampling is provided by swept electrostatic energy/charge selection over the range from 10 eV/q to 30000 eV/q. The eight dual spectrometers on each spacecraft are controlled and interrogated by a single block redundant Instrument Data Processing Unit, which in turn interfaces to the observatory's Instrument Suite Central Instrument Data Processor. This paper describes the design of FPI, its ground and in-flight calibration, its operational concept, and its data products.

  12. Effects of Hemoglobin Variants on Hemoglobin A1c Values Measured Using a High-Performance Liquid Chromatography Method

    PubMed Central

    De-La-Iglesia, Silvia; Ropero, Paloma; Nogueira-Salgueiro, Patricia; Santana-Benitez, Jesus

    2014-01-01

    Hemoglobin A1c (HbA1c) is routinely used to monitor long-term glycemic control and for diagnosing diabetes mellitus. However, hemoglobin (Hb) gene variants/modifications can affect the accuracy of some methods. The potential effect of Hb variants on HbA1c measurements was investigated using a high-performance liquid chromatography (HPLC) method compared with an immunoturbimetric assay. Fasting plasma glucose (FPG) and HbA1c levels were measured in 42 371 blood samples. Samples producing abnormal chromatograms were further analyzed to characterize any Hb variants. Fructosamine levels were determined in place of HbA1c levels when unstable Hb variants were identified. Abnormal HPLC chromatograms were obtained for 160 of 42 371 samples. In 26 samples HbS was identified and HbA1c results correlated with FPG. In the remaining 134 samples HbD, Hb Louisville, Hb Las Palmas, Hb N-Baltimore, or Hb Porto Alegre were identified and HbA1c did not correlate with FPG. These samples were retested using an immunoturbidimetric assay and the majority of results were accurate; only 3 (with the unstable Hb Louisville trait) gave aberrant HbA1c results. Hb variants can affect determination of HbA1c levels with some methods. Laboratories should be aware of Hb variants occurring locally and choose an appropriate HbA1c testing method. PMID:25355712

  13. Blood Test: Hemoglobin A1C

    MedlinePlus

    ... Your 1- to 2-Year-Old Blood Test: Hemoglobin A1c KidsHealth > For Parents > Blood Test: Hemoglobin A1c A A A What's in this article? ... de sangre: hemoglobina A1c What It Is A hemoglobin A1c (HbA1c) test is used to monitor long- ...

  14. A1C Test and Diabetes

    MedlinePlus

    ... Diagnosis The A1C Test & Diabetes The A1C Test & Diabetes What is the A1C test? The A1C test ... A1C test be used to diagnose type 2 diabetes and prediabetes? Yes. In 2009, an international expert ...

  15. Fast Plasma Instrument for MMS: Simulation Results

    NASA Technical Reports Server (NTRS)

    Figueroa-Vinas, Adolfo; Adrian, Mark L.; Lobell, James V.; Simpson, David G.; Barrie, Alex; Winkert, George E.; Yeh, Pen-Shu; Moore, Thomas E.

    2008-01-01

    Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. The Dual Electron Spectrometer (DES) of the Fast Plasma Instrument (FPI) for MMS meets these demanding requirements by acquiring the electron velocity distribution functions (VDFs) for the full sky with high-resolution angular measurements every 30 ms. This will provide unprecedented access to electron scale dynamics within the reconnection diffusion region. The DES consists of eight half-top-hat energy analyzers. Each analyzer has a 6 deg. x 11.25 deg. Full-sky coverage is achieved by electrostatically stepping the FOV of each of the eight sensors through four discrete deflection look directions. Data compression and burst memory management will provide approximately 30 minutes of high time resolution data during each orbit of the four MMS spacecraft. Each spacecraft will intelligently downlink the data sequences that contain the greatest amount of temporal structure. Here we present the results of a simulation of the DES analyzer measurements, data compression and decompression, as well as ground-based analysis using as a seed re-processed Cluster/PEACE electron measurements. The Cluster/PEACE electron measurements have been reprocessed through virtual DES analyzers with their proper geometrical, energy, and timing scale factors and re-mapped via interpolation to the DES angular and energy phase-space sampling measurements. The results of the simulated DES measurements are analyzed and the full moments of the simulated VDFs are compared with those obtained from the Cluster/PEACE spectrometer using a standard quadrature moment, a newly implemented spectral spherical harmonic method, and a singular value decomposition method. Our preliminary moment calculations show a remarkable agreement within the uncertainties of the measurements, with the

  16. Association of Genomic Instability with HbA1c levels and Medication in Diabetic Patients

    PubMed Central

    Grindel, Annemarie; Brath, Helmut; Nersesyan, Armen; Knasmueller, Siegfried; Wagner, Karl-Heinz

    2017-01-01

    Diabetes Mellitus type 2 (DM2) is associated with increased cancer risk. Instability of the genetic material plays a key role in the aetiology of human cancer. This study aimed to analyse genomic instability with the micronucleus cytome assay in exfoliated buccal cells depending on glycated haemoglobin (HbA1c) levels and medication in 146 female DM2 patients. The occurrence of micronuclei was significantly increased in DM2 patients compared to healthy controls. Furthermore, it was doubled in DM2 patients with HbA1c > 7.5% compared to subjects with HbA1c ≤ 7.5%. Positive correlations were found between micronuclei frequencies and HbA1c as well as fasting plasma glucose. Patients under insulin treatment showed a two-fold increase in micronuclei frequencies compared to subjects under first-line medication (no drugs or monotherapy with non-insulin medication). However, after separation of HbA1c (cut-off 7.5%) only patients with severe DM2 characterised by high HbA1c and insulin treatment showed higher micronuclei frequencies but not patients with insulin treatment and low HbA1c. We demonstrated that the severity of DM2 accompanied by elevated micronuclei frequencies predict a possible enhanced cancer risk among female DM2 patients. Therapy, therefore, should focus on a strict HbA1c control and personalised medical treatments. PMID:28150817

  17. EVOLUTION OF FAST MAGNETOACOUSTIC PULSES IN RANDOMLY STRUCTURED CORONAL PLASMAS

    SciTech Connect

    Yuan, D.; Li, B.; Pascoe, D. J.; Nakariakov, V. M.; Keppens, R. E-mail: bbl@sdu.edu.cn

    2015-02-01

    We investigate the evolution of fast magnetoacoustic pulses in randomly structured plasmas, in the context of large-scale propagating waves in the solar atmosphere. We perform one-dimensional numerical simulations of fast wave pulses propagating perpendicular to a constant magnetic field in a low-β plasma with a random density profile across the field. Both linear and nonlinear regimes are considered. We study how the evolution of the pulse amplitude and width depends on their initial values and the parameters of the random structuring. Acting as a dispersive medium, a randomly structured plasma causes amplitude attenuation and width broadening of the fast wave pulses. After the passage of the main pulse, secondary propagating and standing fast waves appear. Width evolution of both linear and nonlinear pulses can be well approximated by linear functions; however, narrow pulses may have zero or negative broadening. This arises because narrow pulses are prone to splitting, while broad pulses usually deviate less from their initial Gaussian shape and form ripple structures on top of the main pulse. Linear pulses decay at an almost constant rate, while nonlinear pulses decay exponentially. A pulse interacts most efficiently with a random medium with a correlation length of about half of the initial pulse width. This detailed model of fast wave pulses propagating in highly structured media substantiates the interpretation of EIT waves as fast magnetoacoustic waves. Evolution of a fast pulse provides us with a novel method to diagnose the sub-resolution filamentation of the solar atmosphere.

  18. Fast Magnetic Reconnection: Bridging Laboratory and Space Plasma Physics

    SciTech Connect

    Bhattacharjee, Amitava

    2012-02-16

    Recent developments in experimental and theoretical studies of magnetic reconnection hold promise for providing solutions to outstanding problems in laboratory and space plasma physics. Examples include sawtooth crashes in tokamaks, substorms in the Earth’s Magnetosphere, eruptive solar flares, and more recently, fast reconnection in laser-produced high energy density plasmas. In each of these examples, a common and long-standing challenge has been to explain why fast reconnection proceeds rapidly from a relatively quiescent state. In this talk, we demonstrate the advantages of viewing these problems and their solutions from a common perspective. We focus on some recent, surprising discoveries regarding the role of secondary plasmoid instabilities of thin current sheets. Nonlinearly, these instabilities lead to fast reconnection rates that are very weakly dependent on the Lundquist number of the plasma.

  19. Interaction of fast magnetoacoustic solitons in dense plasmas

    SciTech Connect

    Jahangir, R.; Saleem, Khalid; Masood, W.; Siddiq, M.; Batool, Nazia

    2015-09-15

    One dimensional propagation of fast magnetoacoustic solitary waves in dense plasmas with degenerate electrons is investigated in this paper in the small amplitude limit. In this regard, Korteweg deVries equation is derived and discussed using the plasma parameters that are typically found in white dwarf stars. The interaction of fast magnetoacoustic solitons is explored by using the Hirota bilinear formalism, which admits multi soliton solutions. It is observed that the values of the propagation vectors determine the interaction of solitary waves. It is further noted that the amplitude of the respective solitary waves remain unchanged after the interaction; however, they do experience a phase shift.

  20. High power, fast, microwave components based on beam generated plasmas

    NASA Astrophysics Data System (ADS)

    Manheimer, W. M.; Fernsler, R. F.; Gitlin, M. S.

    1998-10-01

    It is shown that the agile mirror plasma, under development as a device to simply and cheaply give electronic steering to microwave beams, also has application as a fast, electronically controlled, high power reflector, or phase shifter. In a radar system, this can lead to such applications as pulse to pulse polarization agility and electronic control of antenna gain, as well as to innovative approaches to high power millimeter wave circulators. The basic theory of the enhanced glow plasma is also developed.

  1. Fast Tunable Microwave Devices Using Self-driven Plasma Instabilities

    NASA Astrophysics Data System (ADS)

    Biggs, David; Cappelli, Mark

    2016-10-01

    Tunable electromagnetic devices using plasmas are of interest for various applications such as high frequency communications and analog signal processing. At microwave frequencies of tens of gigahertz, low-pressure plasmas must be employed in order to avoid high wave damping from collisions. The drawback of low-pressure plasmas is that their diffusion timescales are long, on the order of hundreds of microseconds. Other mechanisms than diffusion must be employed to achieve fast tuning capabilities of these devices. One candidate mechanism is to use a self-driven plasma instability, which may allow for fast tuning of microwave resonant cavities. In this work, a microwave resonant cavity is studied consisting of a rectangular waveguide with two conducting posts spaced along the propagation direction to form a rectangular cavity. The cavity acts as a band pass filter and transmits microwave signals around its resonant frequency. Plasma may be introduced into the cavity between the conducting posts in order to change the refractive index and thus the resonant and transmission frequency of the device. The location of the plasma and its plasma density are important parameters in determining the resonant frequency, and both parameters are capable of being tuned with plasma instabilities. This work is supported by the Air Force Office of Scientific Research.

  2. Hemoglobin A1c and Self-Monitored Average Glucose

    PubMed Central

    Kovatchev, Boris P.; Breton, Marc D.

    2015-01-01

    Background: Previously we have introduced the eA1c—a new approach to real-time tracking of average glycemia and estimation of HbA1c from infrequent self-monitoring (SMBG) data, which was developed and tested in type 2 diabetes. We now test eA1c in type 1 diabetes and assess its relationship to the hemoglobin glycation index (HGI)—an established predictor of complications and treatment effect. Methods: Reanalysis of previously published 12-month data from 120 patients with type 1 diabetes, age 39.15 (14.35) years, 51/69 males/females, baseline HbA1c = 7.99% (1.48), duration of diabetes 20.28 (12.92) years, number SMBG/day = 4.69 (1.84). Surrogate fasting BG and 7-point daily profiles were derived from these unstructured SMBG data and the previously reported eA1c method was applied without any changes. Following the literature, we calculated HGI = HbA1c – (0.009 × Fasting BG + 6.8). Results: The correlation of eA1c with reference HbA1c was r = .75, and its deviation from reference was MARD = 7.98%; 95% of all eA1c values fell within ±20% from reference. The HGI was well approximated by a linear combination of the eA1c calibration factors: HGI = 0.007552*θ1 + 0.007645*θ2 – 3.154 (P < .0001); 73% of low versus moderate-high HGIs were correctly classified by the same factors as well. Conclusions: The eA1c procedure developed in type 2 diabetes to track in real-time changes in average glycemia and present the results in HbA1c-equivalent units has shown similar performance in type 1 diabetes. The eA1c calibration factors are highly predictive of the HGI, thereby explaining partially the biological variation causing discrepancies between HbA1c and its linear estimates from SMBG data. PMID:26553023

  3. A Midsize Tokamak As Fast Track To Burning Plasmas

    SciTech Connect

    E. Mazzucato

    2010-07-14

    This paper presents a midsize tokamak as a fast track to the investigation of burning plasmas. It is shown that it could reach large values of energy gain (≥10) with only a modest improvement in confinement over the scaling that was used for designing the International Thermonuclear Experimental Reactor (ITER). This could be achieved by operating in a low plasma recycling regime that experiments indicate can lead to improved plasma confinement. The possibility of reaching the necessary conditions of low recycling using a more efficient magnetic divertor than those of present tokamaks is discussed.

  4. Physical conditions for fast reconnection evolution in space plasmas

    SciTech Connect

    Ugai, M.

    2012-07-15

    The present paper studies physical conditions for fast reconnection mechanism involving slow shocks to evolve spontaneously in space (high-temperature) plasmas. This is fundamental for onset mechanisms of geomagnetic substorms and solar flares. It is demonstrated that reconnection evolution strongly depends on effective resistivity available in space plasmas as well as on dimensions of initial current sheet. If a current sheet is sufficiently thin, fast reconnection spontaneously evolves only when resistivity is locally enhanced around X reconnection point. This is because in space plasmas reconnection flows cause vital current concentration locally around X point. For current-driven anomalous resistivity, the resulting resistivity is automatically localized around X point, so fast reconnection mechanism can be realized. On the other hand, for uniform or Spitzer resistivity, any fast reconnection cannot grow; in particular, Spitzer resistivity is reduced around X point because of Joule heating. Regarding reconnection simulations (either fluid or particle), unless numerical resistivities are made negligibly small, they seriously mask the effects of physical resistivity, leading to a misleading conclusion that reconnection evolution is little influenced by plasma resistivity.

  5. Measuring Fast Ion Losses in a Reversed Field Pinch Plasma

    NASA Astrophysics Data System (ADS)

    Bonofiglo, P. J.; Anderson, J. K.; Almagri, A. F.; Kim, J.; Clark, J.; Capecchi, W.; Sears, S. H.

    2015-11-01

    The reversed field pinch (RFP) provides a unique environment to study fast ion confinement and transport. The RFP's weak toroidal field, strong magnetic shear, and ability to enter a 3D state provide a wide range of dynamics to study fast ions. Core-localized, 25 keV fast ions are sourced into MST by a tangentially injected hydrogen/deuterium neutral beam. Neutral particle analysis and measured fusion neutron flux indicate enhanced fast ion transport in the plasma core. Past experiments point to a dynamic loss of fast ions associated with the RFP's transition to a 3D state and with beam-driven, bursting magnetic modes. Consequently, fast ion transport and losses in the RFP have garnered recent attention. Valuable information on fast-ion loss, such as energy and pitch distributions, are sought to provide a better understanding of the transport mechanisms at hand. We have constructed and implemented two fast ion loss detectors (FILDs) for use on MST. The FILDs have two, independent, design concepts: collecting particles as a function of v⊥ or with pitch greater than 0.8. In this work, we present our preliminary findings and results from our FILDs on MST. This research is supported by US DOE.

  6. Plasma instability in fast spherical discharge induced by a preionization

    SciTech Connect

    Antsiferov, P. S.; Dorokhin, L. A.

    2015-04-07

    As it was shown earlier, fast discharge (dI/dt ∼ 10{sup 12 }A/s and I{sub max} ≈ 40 kA) in a spherical cavity (Al{sub 2}O{sub 3}, inner diameter 11 mm, 4 mm apertures for the current supply) filled with working gas (Ar and Xe, pressure 80 Pa), results in the formation of a plasma with the form close to spherical. The physical mechanism can be the cumulation of a convergent shock wave, which was originated near the inner surface of the discharge cavity. It was also shown for the cylindrical fast discharge that the preionization influences the dynamics of the cylindrical convergent shock wave, its evolutions becomes faster. The present work is devoted to the study of the influence of the preionization on the plasma formation in the fast discharge with spherical geometry (Ar, 80 Pa). The inductive storage with plasma erosion opening switch was used as a current driver. The spatial structure of the discharge plasma was studied by means of a pin-hole camera with the microchannel plate (MCP) detector with time gate of 5 ns. The extreme ultra violet spectra were studied by means of the grazing incidence spectrometer with the same MCP detector with time gate of 20 ns. Beside the expected effects (reduction of the spherical plasma formation time and some increase of the electron temperature), the preionization of the discharge by the current 500 A results also in the development of the plasma instabilities and destruction of the compact plasma ball in several tens of nanoseconds. Possible mechanism of the instability is discussed.

  7. Plasma instability in fast spherical discharge induced by a preionization

    NASA Astrophysics Data System (ADS)

    Antsiferov, P. S.; Dorokhin, L. A.

    2015-04-01

    As it was shown earlier, fast discharge (dI/dt ˜ 1012 A/s and Imax ≈ 40 kA) in a spherical cavity (Al2O3, inner diameter 11 mm, 4 mm apertures for the current supply) filled with working gas (Ar and Xe, pressure 80 Pa), results in the formation of a plasma with the form close to spherical. The physical mechanism can be the cumulation of a convergent shock wave, which was originated near the inner surface of the discharge cavity. It was also shown for the cylindrical fast discharge that the preionization influences the dynamics of the cylindrical convergent shock wave, its evolutions becomes faster. The present work is devoted to the study of the influence of the preionization on the plasma formation in the fast discharge with spherical geometry (Ar, 80 Pa). The inductive storage with plasma erosion opening switch was used as a current driver. The spatial structure of the discharge plasma was studied by means of a pin-hole camera with the microchannel plate (MCP) detector with time gate of 5 ns. The extreme ultra violet spectra were studied by means of the grazing incidence spectrometer with the same MCP detector with time gate of 20 ns. Beside the expected effects (reduction of the spherical plasma formation time and some increase of the electron temperature), the preionization of the discharge by the current 500 A results also in the development of the plasma instabilities and destruction of the compact plasma ball in several tens of nanoseconds. Possible mechanism of the instability is discussed.

  8. The Fast Plasma Investigation on the Magnetospheric Multiscale Mission

    NASA Astrophysics Data System (ADS)

    Rager, A. C.; Pollock, C. J.; Avanov, L. A.; Barrie, A. C.; Burch, J. L.; Chandler, M. O.; Clark, G. B.; Coffey, V. N.; Dickson, C.; Dorelli, J.; Ergun, R.; Fuselier, S. A.; Gliese, U.; Giles, B. L.; Holland, M. P.; Jacques, A. D.; Kreisler, S.; Lavraud, B.; MacDonald, E.; Mauk, B.; Moore, T. E.; Mukai, T.; Nakamura, R.; Rosnack, T.; Saito, Y.; Salo, C.; Sauvaud, J. A.; Smith, D. L.; Smith, S. E.; Torbert, R. B.; Yokota, S.

    2015-12-01

    Launched in March 2015, the Fast Plasma Investigation (FPI) instrument suite on the Magnetospheric Multiscale Mission (MMS) is producing the highest time and spatial resolution 3D electron and ion particle distribution function measurements to date. During FPI science operations, the four spacecraft maintain a tetrahedral formation such that 3D measurements of the plasma and field gradients are enabled. This allows the spacecraft to better investigate reconnection and to distinguish between spatial and temporal structures. In the first three months, we expect to observe magnetic phenomena such as dipolarization fronts, the plasma sheet boundary layer, magnetopause crossings, ion dispersive signatures of from remote reconnection sites, and magnetic holes. This poster is intended to supplement the invited talk on FPI results by Pollock et al. by providing further detail of the instrumentation and calibration, as well as a sampling of early magnetospheric plasma observations in the evening-side magnetotail, dusk flank, and afternoon magnetopause.

  9. HbA1c and Glycated Albumin Levels Are High in Gastrectomized Subjects with Iron-Deficiency Anemia.

    PubMed

    Inada, Shinya; Koga, Masafumi

    2017-01-01

    We report that glycated albumin (GA) is higher relative to HbA1c in non-diabetic, gastrectomized subjects without anemia, and thus is a sign of oxyhyperglycemia. It is known that gastrectomized subjects are prone to iron-deficiency anemia (IDA), and that the HbA1c levels of subjects with IDA are falsely high. In the present study, the HbA1c and GA levels of gastrectomized subjects with IDA were compared with gastrectomized subjects without anemia. Seven non-diabetic gastrectomized subjects with IDA were enrolled in the present study. Twenty-eight non-diabetic gastrectomized subjects without anemia matched with the subjects with IDA in terms of age, gender, and body mass index were used as the controls. Although there were no significant differences in fasting plasma glucose and OGTT 2-hour plasma glucose (2-h PG) between the two groups, the HbA1c and GA levels in gastrectomized subjects with IDA were significantly higher than the controls. For all of the gastrectomized subjects (n=35), ferritin exhibited a significant negative correlation with HbA1c and GA, and a significant positive correlation with 2-h PG. In addition, the HbA1c and GA levels exhibited a significant negative correlation with the mean corpuscular hemoglobin and hemoglobin. The HbA1c and GA levels in gastrectomized subjects with IDA were significantly higher than those in controls. The high GA levels are attributed to a tendency in which patients with total gastrectomy, who are prone to IDA, are susceptible to postprandial hyperglycemia and reactive hypoglycemia, which in turn leads to large fluctuations in plasma glucose.

  10. Interaction between high harmonic fast waves and fast ions in NSTX/NSTX-U plasmas

    NASA Astrophysics Data System (ADS)

    Bertelli, N.; Valeo, E. J.; Gorelenkova, M.; Green, D. L.; RF SciDAC Team

    2016-10-01

    Fast wave (FW) heating in the ion cyclotron range of frequency (ICRF) has been successfully used to sustain and control the fusion plasma performance, and it will likely play an important role in the ITER experiment. As demonstrated in the NSTX and DIII-D experiments the interactions between fast waves and fast ions can be so strong to significantly modify the fast ion population from neutral beam injection. In fact, it has been recently found in NSTX that FWs can modify and, under certain conditions, even suppress the energetic particle driven instabilities, such as toroidal Alfvén eigenmodes and global Alfvén eigenmodes and fishbones. This paper examines such interactions in NSTX/NSTX-U plasmas by using the recent extension of the RF full-wave code TORIC to include non-Maxwellian ions distribution functions. Particular attention is given to the evolution of the fast ions distribution function w/ and w/o RF. Tests on the RF kick-operator implemented in the Monte-Carlo particle code NUBEAM is also discussed in order to move towards a self consistent evaluation of the RF wave-field and the ion distribution functions in the TRANSP code. Work supported by US DOE Contract DE-AC02-09CH11466.

  11. Fast discharge in a plasma gun with hemispherical insulator

    SciTech Connect

    Antsiferov, P. S.; Dorokhin, L. A.; Sidelnikov, Yu. V.; Koshelev, K. N.

    2009-05-15

    A method of creation of hot dense plasma is proposed. It is based on cumulation of a shockwave, which originates on a hemispherical surface of insulator of plasma gun. The results of first experiments are presented. The shock wave is driven by fast electrical discharge (dI/dt>10{sup 12} A/s). The inductive storage with semiconductor opening switch is used as a current driver. Time resolved pin-hole images and vacuum ultraviolet (vuv) spectra are studied. Shockwaves from hemispherical insulator with 4 mm radius create plasma with a form of column about 1 mm diameter and 3-4 mm length. vuv spectra contain the lines of Ar ions that corresponds to the electron temperature about 20 eV. Possible practical application is discussed.

  12. Fast plasma heating by anomalous and inertial resistivity effects

    NASA Technical Reports Server (NTRS)

    Duijveman, A.; Hoyng, P.; Ionson, J. A.

    1981-01-01

    Fast plasma heating by anomalous and inertial resistivity effects is described. A small fraction of the plasma contains strong currents that run parallel to the magnetic field and are driven by an exponentiating electric field. The anomalous character of the current dissipation is caused by the excitation of electrostatic ion cyclotron and/or ion acoustic waves. The role of resistivity due to geometrical effects is considered. Through the use of a marginal stability analysis, equations for the average electron and ion temperatures are derived and numerically solved. The evolution of the plasma is described as a path in the drift velocity diagram, in which the drift velocity is plotted as a function of the electron to ion temperature ratio.

  13. Blood Test: Hemoglobin A1C

    MedlinePlus

    ... few minutes. previous continue What to Expect Either method (finger or heel sticking or vein withdrawal) of ... that since labs and offices may use different methods to measure HbA1c, the range of normal values ...

  14. A1C and eAG

    MedlinePlus

    ... Complications DKA (Ketoacidosis) & Ketones Kidney Disease (Nephropathy) Gastroparesis Mental Health Step On Up Treatment & Care Blood Glucose Testing Medication Doctors, Nurses & More Oral Health & Hygiene Women A1C Insulin Pregnancy ...

  15. Plasma Distribution in Mercury's Magnetosphere Derived from MESSENGER Magnetometer and Fast Imaging Plasma Spectrometer Observations

    NASA Technical Reports Server (NTRS)

    Korth, Haje; Anderson, Brian J.; Gershman, Daniel J.; Raines, Jim M.; Slavin, James A.; Zurbuchen, Thomas H.; Solomon, Sean C.; McNutt, Ralph L.

    2014-01-01

    We assess the statistical spatial distribution of plasma in Mercury's magnetosphere from observations of magnetic pressure deficits and plasma characteristics by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. The statistical distributions of proton flux and pressure were derived from 10months of Fast Imaging Plasma Spectrometer (FIPS) observations obtained during the orbital phase of the MESSENGER mission. The Magnetometer-derived pressure distributions compare favorably with those deduced from the FIPS observations at locations where depressions in the magnetic field associated with the presence of enhanced plasma pressures are discernible in the Magnetometer data. The magnitudes of the magnetic pressure deficit and the plasma pressure agree on average, although the two measures of plasma pressure may deviate for individual events by as much as a factor of approximately 3. The FIPS distributions provide better statistics in regions where the plasma is more tenuous and reveal an enhanced plasma population near the magnetopause flanks resulting from direct entry of magnetosheath plasma into the low-latitude boundary layer of the magnetosphere. The plasma observations also exhibit a pronounced north-south asymmetry on the nightside, with markedly lower fluxes at low altitudes in the northern hemisphere than at higher altitudes in the south on the same field line. This asymmetry is consistent with particle loss to the southern hemisphere surface during bounce motion in Mercury's offset dipole magnetic field.

  16. Gestational diabetes mellitus: Screening with fasting plasma glucose

    PubMed Central

    Agarwal, Mukesh M

    2016-01-01

    Fasting plasma glucose (FPG) as a screening test for gestational diabetes mellitus (GDM) has had a checkered history. During the last three decades, a few initial anecdotal reports have given way to the recent well-conducted studies. This review: (1) traces the history; (2) weighs the advantages and disadvantages; (3) addresses the significance in early pregnancy; (4) underscores the benefits after delivery; and (5) emphasizes the cost savings of using the FPG in the screening of GDM. It also highlights the utility of fasting capillary glucose and stresses the value of the FPG in circumventing the cumbersome oral glucose tolerance test. An understanding of all the caveats is crucial to be able to use the FPG for investigating glucose intolerance in pregnancy. Thus, all health professionals can use the patient-friendly FPG to simplify the onerous algorithms available for the screening and diagnosis of GDM - thereby helping each and every pregnant woman. PMID:27525055

  17. Association between Inflammation and Biological Variation in Hemoglobin A1c in U.S. Nondiabetic Adults

    PubMed Central

    Liu, Shuqian; Hempe, James M.; McCarter, Robert J.; Li, Shengxu

    2015-01-01

    Context: Inflammation is associated with higher glycated hemoglobin (HbA1c) levels. Whether the relationship is independent of blood glucose concentration remains unclear. Objective: The hemoglobin glycation index (HGI) was used to test the hypothesis that interindividual variation in HbA1c is associated with inflammation. Participants: This study used nondiabetic adults from the National Health and Nutrition Examination Survey (1999–2008). Main Outcome Measures: A subsample of participants was used to estimate the linear regression relationship between HbA1c and fasting plasma glucose (FPG). Predicted HbA1c were calculated for 7323 nondiabetic participants by inserting FPG into the equation, HbA1c = 0.017× FPG (mg/dL) + 3.7. HGI was calculated as the difference between the observed and predicted HbA1c and the population was divided into low, moderate, and high HGI subgroups. Polymorphonuclear leukocytes (PMNL), monocytes, and C-reactive protein (CRP) were used as biomarkers of inflammation. Results: Mean HbA1c, CRP, monocyte, and PMNL levels, but not FPG, progressively increased in the low, moderate, and high HGI subgroups. There were disproportionately more Blacks than whites in the high HGI subgroup. CRP (ß, 0.009; 95% confidence interval [CI], 0.0001–0.017), PMNL (ß, 0.036; 95% CI, 0.010–0.062), and monocyte count (ß, 0.072; 95% CI, 0.041–0.104) were each independent predictors of HGI after adjustment for age, sex, race, triglycerides, hemoglobin level, mean corpuscular volume, red cell distribution width, and obesity status. Conclusions: HGI reflects the effects of inflammation on HbA1c in a nondiabetic population of U.S. adults and may be a marker of risk associated with inflammation independent of FPG, race, and obesity. PMID:25867810

  18. Observation of Ion Cyclotron Heating in a Fast-flowing Plasma for an Advanced Plasma Thruster

    NASA Astrophysics Data System (ADS)

    Ando, Akira; Hatanaka, Motoi; Shibata, Masaki; Tobari, Hiroyuki; Hattori, Kunihiko; Inutake, Masaaki

    2004-11-01

    In the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) project in NASA, the combined system of the ion cyclotron heating and the magnetic nozzle is proposed to control a ratio of specific impulse to thrust at constant power. In order to establish the advanced plasma thruster, experiments of an ion heating and plasma acceleration by a magnetic nozzle are performed in a fast-flowing plasma in the HITOP device. A fast-flowing He plasma is produced by Magneto-Plasma-Dynamic Arcjet (MPDA) operated with an externally-applied magnetic field up to 1kG. RF waves with an ion cyclotron range of frequency (f=20-300kHz) is excited by a helically-wound antenna located downstream of the MPDA. Increases of an ion temperature and plasma stored energy measured by a diamagnetic coil clearly observed during the RF pulse. The heating efficiency is compared for various magnetic field configurations and strengths. There appears no indication of cyclotron resonance in a high density plasma where the ratio of ion cyclotron frequency to ion-ion collision one is below unity, because an ion-ion collisional effect is dominant. When the density becomes low and the ratio of ion cyclotron frequency to ion-ion collision one becomes high, features of ion cyclotron resonance are clearly appeared. The optimum magnetic field strength for the ion heating is slightly lower than that of the cyclotron resonance, which is caused by the Doppler effect due to the fast-flowing plasma. An ion energy distribution function is measured at a magnetic nozzle region by an electrostatic analyzer and increase of the parallel velocity is also observed.

  19. Fast moving plasma structures in the distant magnetotail

    NASA Technical Reports Server (NTRS)

    Scholer, M.; Klecker, B.; Hovestadt, D.; Gloeckler, G.; Ipavich, F. M.; Smith, E. J.

    1984-01-01

    The paper reports for the first time the detailed time behavior of the intensities and the angular distributions of energetic protons and electrons in the distant magnetotail of the earth at 220 earth radii and 110 earth radii. The data have been obtained by the Max-Planck-Institut/University of Maryland sensor system on ISEE 3 during the spacecraft's first deep tail passage. Three energetic particle bursts are studied in detail. It is suggested that the satellite encounters detached plasma structures evidenced by the isotropic electrons. These structures, probably plasmoids, move with high velocities (about 800 km/s) down the tail. The energetic electrons and protons stream ahead of these fast tailward moving plasma structures, which leads to the various time dispersion effects. This allows, in principle, a determination of the source distance from the satellite.

  20. Association Between the Presence of Iron Deficiency Anemia and Hemoglobin A1c in Korean Adults

    PubMed Central

    Hong, Jae W.; Ku, Cheol R.; Noh, Jung H.; Ko, Kyung S.; Rhee, Byoung D.; Kim, Dong-Jun

    2015-01-01

    Abstract Few studies have investigated the clinical effect of iron deficiency anemia (IDA) on the use of the Hemoglobin A1c (HbA1c) as a screening parameter for diabetes or prediabetes. We investigated the association between IDA and HbA1c levels in Korean adults. Among the 11,472 adults (≥19 years of age) who participated in the 2011–2012 Korea National Health and Nutrition Examination Survey (a cross-sectional and nationally representative survey conducted by the Korean Center for Disease Control for Health Statistics), 807 patients with diabetes currently taking anti-diabetes medications were excluded from this study. We compared the weighted HbA1c levels and weighted proportion (%) of HbA1c levels of ≥5.7%, ≥6.1%, and ≥6.5% according to the range of fasting plasma glucose (FPG) levels and the presence of IDA. Among 10,665 participants (weighted n = 35,229,108), the prevalence of anemia and IDA was 7.3% and 4.3%, respectively. The HbA1c levels were higher in participants with IDA (5.70% ± 0.02%) than in normal participants (5.59% ± 0.01%; P < 0.001), whereas there was no significant difference in FPG levels. In participants with an FPG level of <100 mg/dL and 100 to 125 mg/dL, the weighted HbA1c level was higher in those with IDA (5.59% ± 0.02% and 6.00% ± 0.05%) than in normal participants (5.44% ± 0.01% and 5.82% ± 0.01%) after adjusting for confounders such as age, sex, FPG level, heavy alcohol drinking, waist circumference, and smoking status as well as after exclusion of an estimated glomerular filtration rate of <60 mL/min/1.73 m2 (P < 0.001, <0.01). The weighted proportions (%) of an HbA1c level of ≥5.7% and ≥6.1% were also higher in participants with IDA than in normal participants (P < 0.001, <0.05). However, the weighted HbA1c levels in individuals with an FPG level ≥126 mg/dL and a weighted proportion (%) of an HbA1c level of ≥6.5% showed no significant differences according to

  1. Plasma distribution in Mercury's magnetosphere inferred from MESSENGER Magnetometer and Fast Imaging Plasma Spectrometer observations

    NASA Astrophysics Data System (ADS)

    Korth, H.; Anderson, B. J.; Raines, J. M.; Gershman, D. J.; Slavin, J. A.; Zurbuchen, T.; Solomon, S. C.; McNutt, R. L., Jr.

    2013-12-01

    We present average plasma distributions in Mercury's magnetosphere inferred independently from magnetic field and plasma measurements by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. Plasma distributions were derived from magnetic pressure deficits measured during the first 10 months of MESSENGER orbital operations under the assumption of constant total pressure. Statistical distributions of proton flux and pressure were also derived from Fast Imaging Plasma Spectrometer (FIPS) observations during the same period. The pressures inferred from magnetic pressure deficits and the plasma data agree on average, although they differ by a factor of ~2 for individual events. The spatial distributions of magnetic pressure deficits derived from Magnetometer observations compare favorably with the distribution of proton pressure deduced from the FIPS observations. The FIPS distributions provide better statistics than the magnetic depression data in regions where the plasma is more tenuous and magnetic pressure deficits are difficult to identify definitively. The plasma data reveal features not previously identified in the Magnetometer data, such as an enhanced plasma population near the magnetopause flanks indicating entry of magnetosheath plasma into the low-latitude boundary layer of the magnetosphere. On nightside closed field lines, plasma pressures in the south are much greater than they are in the north. Locations of low plasma pressure in the north correspond to sample altitudes that map to southern conjugate locations below the planetary surface. The asymmetry is attributed to particle loss to the southern hemisphere surface during bounce motion in Mercury's magnetic field. The plasma observations confirm the northward offset in the planetary dipole.

  2. Collimated fast electron beam generation in critical density plasma

    SciTech Connect

    Iwawaki, T. Habara, H.; Morita, K.; Tanaka, K. A.; Baton, S.; Fuchs, J.; Chen, S.; Nakatsutsumi, M.; Rousseaux, C.; Filippi, F.; Nazarov, W.

    2014-11-15

    Significantly collimated fast electron beam with a divergence angle 10° (FWHM) is observed when an ultra-intense laser pulse (I = 10{sup 14 }W/cm{sup 2}, 300 fs) irradiates a uniform critical density plasma. The uniform plasma is created through the ionization of an ultra-low density (5 mg/c.c.) plastic foam by X-ray burst from the interaction of intense laser (I = 10{sup 14 }W/cm{sup 2}, 600 ps) with a thin Cu foil. 2D Particle-In-Cell (PIC) simulation well reproduces the collimated electron beam with a strong magnetic field in the region of the laser pulse propagation. To understand the physical mechanism of the collimation, we calculate energetic electron motion in the magnetic field obtained from the 2D PIC simulation. As the results, the strong magnetic field (300 MG) collimates electrons with energy over a few MeV. This collimation mechanism may attract attention in many applications such as electron acceleration, electron microscope and fast ignition of laser fusion.

  3. Are the ADA hemoglobin A(1c) criteria relevant for the diagnosis of type 2 diabetes in youth?

    PubMed

    Kapadia, Chirag R

    2013-02-01

    Diagnostic criteria for diabetes in children have not been established with nearly the rigor as that employed in adults. Recently revised American Diabetes Association (ADA) criteria allowed utilization of hemoglobin A(1c) (HbA1c) ≥ 6.5 % for diagnosis of diabetes. A recent series of pediatric studies appear to show that HbA1c has lower sensitivity than Fasting plasma glucose (FPG) or oral glucose tolerance test (OGTT). However, FPG and OGTT have themselves never been validated in children. Studies to validate diagnostic thresholds in children appear unlikely to take place. Thus, accepting the major ADA diagnostic criteria appears to be the best course of action for the pediatric community. One area in which correlation studies between HbA1c and FPG or OGTT might shed light is in the definition of criteria for intervention in 'pre-diabetes,' as the Diabetes Prevention Program Trial did not use HbA1c. However, such treatment, and the exact diagnostic thresholds at which it should be initiated in children, remains unproven.

  4. Hybrid Simulation of Laser-Plasma Interactions and Fast Electron Transport in Inhomogeneous Plasma

    SciTech Connect

    Cohen, B I; Kemp, A; Divol, L

    2009-05-27

    A new framework is introduced for kinetic simulation of laser-plasma interactions in an inhomogenous plasma motivated by the goal of performing integrated kinetic simulations of fast-ignition laser fusion. The algorithm addresses the propagation and absorption of an intense electromagnetic wave in an ionized plasma leading to the generation and transport of an energetic electron component. The energetic electrons propagate farther into the plasma to much higher densities where Coulomb collisions become important. The high-density plasma supports an energetic electron current, return currents, self-consistent electric fields associated with maintaining quasi-neutrality, and self-consistent magnetic fields due to the currents. Collisions of the electrons and ions are calculated accurately to track the energetic electrons and model their interactions with the background plasma. Up to a density well above critical density, where the laser electromagnetic field is evanescent, Maxwell's equations are solved with a conventional particle-based, finite-difference scheme. In the higher-density plasma, Maxwell's equations are solved using an Ohm's law neglecting the inertia of the background electrons with the option of omitting the displacement current in Ampere's law. Particle equations of motion with binary collisions are solved for all electrons and ions throughout the system using weighted particles to resolve the density gradient efficiently. The algorithm is analyzed and demonstrated in simulation examples. The simulation scheme introduced here achieves significantly improved efficiencies.

  5. Simulation of laser-plasma interactions and fast-electron transport in inhomogeneous plasma

    SciTech Connect

    Cohen, B.I. Kemp, A.J.; Divol, L.

    2010-06-20

    A new framework is introduced for kinetic simulation of laser-plasma interactions in an inhomogeneous plasma motivated by the goal of performing integrated kinetic simulations of fast-ignition laser fusion. The algorithm addresses the propagation and absorption of an intense electromagnetic wave in an ionized plasma leading to the generation and transport of an energetic electron component. The energetic electrons propagate farther into the plasma to much higher densities where Coulomb collisions become important. The high-density plasma supports an energetic electron current, return currents, self-consistent electric fields associated with maintaining quasi-neutrality, and self-consistent magnetic fields due to the currents. Collisions of the electrons and ions are calculated accurately to track the energetic electrons and model their interactions with the background plasma. Up to a density well above critical density, where the laser electromagnetic field is evanescent, Maxwell's equations are solved with a conventional particle-based, finite-difference scheme. In the higher-density plasma, Maxwell's equations are solved using an Ohm's law neglecting the inertia of the background electrons with the option of omitting the displacement current in Ampere's law. Particle equations of motion with binary collisions are solved for all electrons and ions throughout the system using weighted particles to resolve the density gradient efficiently. The algorithm is analyzed and demonstrated in simulation examples. The simulation scheme introduced here achieves significantly improved efficiencies.

  6. The Electron and ion Plasma Experiment for Fast

    NASA Astrophysics Data System (ADS)

    Carlson, C. W.; McFadden, J. P.; Turin, P.; Curtis, D. W.; Magoncelli, A.

    2001-08-01

    The ion and electron plasma experiment on the Fast Auroral Snapshot satellite (FAST) is designed to measure pitch-angle distributions of suprathermal auroral electrons and ions with high sensitivity, wide dynamic range, good energy and angular resolution, and exceptional time resolution. These measurements support the primary scientific goal of the FAST mission to understand the physical processes responsible for auroral particle acceleration and heating, and associated wave-particle interactions. The instrument includes a complement of 8 pairs of `Top Hat' electrostatic analyzer heads with microchannel plate (MCP) electron multipliers and discrete anodes to provide angle resolved measurements. The analyzers are packaged in four instrument stacks, each containing four analyzers. These four stacks are equally spaced around the spacecraft spin plane. Analyzers mounted on opposite sides of the spacecraft operate in pairs such that their individual 180° fields of view combine to give an unobstructed 360° field of view in the spin plane. The earth's magnetic field is within a few degrees of the spin plane during most auroral crossings, so the time resolution for pitch-angle distribution measurements is independent of the spacecraft spin period. Two analyzer pairs serve as electron and ion spectrometers that obtain distributions of 48 energies at 32 angles every 78 ms. Their standard energy ranges are 4 eV to 32 keV for electrons and 3 eV to 24 keV for ions. These sensors also have deflection plates that can track the magnetic field direction within 10° of the spin plane to resolve narrow, magnetic field-aligned beams of electrons and ions. The remaining six analyzer pairs collectively function as an electron spectrograph, resolving distributions with 16 contiguous pitch-angle bins and a selectable trade-off of energy and time resolution. Two examples of possible operating modes are a maximum time resolution mode with 16 angles and 6 energies every 1.63 ms, or a

  7. Optimizing Dense Plasma Focus Neutron Yields with Fast Gas Jets

    NASA Astrophysics Data System (ADS)

    McMahon, Matthew; Kueny, Christopher; Stein, Elizabeth; Link, Anthony; Schmidt, Andrea

    2016-10-01

    We report a study using the particle-in-cell code LSP to perform fully kinetic simulations modeling dense plasma focus (DPF) devices with high density gas jets on axis. The high density jet models fast gas puffs which allow for more mass on axis while maintaining the optimal pressure for the DPF. As the density of the jet compared to the background fill increases we find the neutron yield increases, as does the variability in the neutron yield. Introducing perturbations in the jet density allow for consistent seeding of the m =0 instability leading to more consistent ion acceleration and higher neutron yields with less variability. Jets with higher on axis density are found to have the greatest yield. The optimal jet configuration is explored. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  8. Dense magnetized plasma associated with a fast radio burst

    NASA Astrophysics Data System (ADS)

    Masui, Kiyoshi; Lin, Hsiu-Hsien; Sievers, Jonathan; Anderson, Christopher J.; Chang, Tzu-Ching; Chen, Xuelei; Ganguly, Apratim; Jarvis, Miranda; Kuo, Cheng-Yu; Li, Yi-Chao; Liao, Yu-Wei; McLaughlin, Maura; Pen, Ue-Li; Peterson, Jeffrey B.; Roman, Alexander; Timbie, Peter T.; Voytek, Tabitha; Yadav, Jaswant K.

    2015-12-01

    Fast radio bursts are bright, unresolved, non-repeating, broadband, millisecond flashes, found primarily at high Galactic latitudes, with dispersion measures much larger than expected for a Galactic source. The inferred all-sky burst rate is comparable to the core-collapse supernova rate out to redshift 0.5. If the observed dispersion measures are assumed to be dominated by the intergalactic medium, the sources are at cosmological distances with redshifts of 0.2 to 1 (refs 10 and 11). These parameters are consistent with a wide range of source models. One fast burst revealed circular polarization of the radio emission, but no linear polarization was detected, and hence no Faraday rotation measure could be determined. Here we report the examination of archival data revealing Faraday rotation in the fast radio burst FRB 110523. Its radio flux and dispersion measure are consistent with values from previously reported bursts and, accounting for a Galactic contribution to the dispersion and using a model of intergalactic electron density, we place the source at a maximum redshift of 0.5. The burst has a much higher rotation measure than expected for this line of sight through the Milky Way and the intergalactic medium, indicating magnetization in the vicinity of the source itself or within a host galaxy. The pulse was scattered by two distinct plasma screens during propagation, which requires either a dense nebula associated with the source or a location within the central region of its host galaxy. The detection in this instance of magnetization and scattering that are both local to the source favours models involving young stellar populations such as magnetars over models involving the mergers of older neutron stars, which are more likely to be located in low-density regions of the host galaxy.

  9. Dense magnetized plasma associated with a fast radio burst.

    PubMed

    Masui, Kiyoshi; Lin, Hsiu-Hsien; Sievers, Jonathan; Anderson, Christopher J; Chang, Tzu-Ching; Chen, Xuelei; Ganguly, Apratim; Jarvis, Miranda; Kuo, Cheng-Yu; Li, Yi-Chao; Liao, Yu-Wei; McLaughlin, Maura; Pen, Ue-Li; Peterson, Jeffrey B; Roman, Alexander; Timbie, Peter T; Voytek, Tabitha; Yadav, Jaswant K

    2015-12-24

    Fast radio bursts are bright, unresolved, non-repeating, broadband, millisecond flashes, found primarily at high Galactic latitudes, with dispersion measures much larger than expected for a Galactic source. The inferred all-sky burst rate is comparable to the core-collapse supernova rate out to redshift 0.5. If the observed dispersion measures are assumed to be dominated by the intergalactic medium, the sources are at cosmological distances with redshifts of 0.2 to 1 (refs 10 and 11). These parameters are consistent with a wide range of source models. One fast burst revealed circular polarization of the radio emission, but no linear polarization was detected, and hence no Faraday rotation measure could be determined. Here we report the examination of archival data revealing Faraday rotation in the fast radio burst FRB 110523. Its radio flux and dispersion measure are consistent with values from previously reported bursts and, accounting for a Galactic contribution to the dispersion and using a model of intergalactic electron density, we place the source at a maximum redshift of 0.5. The burst has a much higher rotation measure than expected for this line of sight through the Milky Way and the intergalactic medium, indicating magnetization in the vicinity of the source itself or within a host galaxy. The pulse was scattered by two distinct plasma screens during propagation, which requires either a dense nebula associated with the source or a location within the central region of its host galaxy. The detection in this instance of magnetization and scattering that are both local to the source favours models involving young stellar populations such as magnetars over models involving the mergers of older neutron stars, which are more likely to be located in low-density regions of the host galaxy.

  10. Fast reconnection in relativistic plasmas: the magnetohydrodynamics tearing instability revisited

    NASA Astrophysics Data System (ADS)

    Del Zanna, L.; Papini, E.; Landi, S.; Bugli, M.; Bucciantini, N.

    2016-08-01

    Fast reconnection operating in magnetically dominated plasmas is often invoked in models for magnetar giant flares, for magnetic dissipation in pulsar winds, or to explain the gamma-ray flares observed in the Crab nebula; hence, its investigation is of paramount importance in high-energy astrophysics. Here we study, by means of two-dimensional numerical simulations, the linear phase and the subsequent non-linear evolution of the tearing instability within the framework of relativistic resistive magnetohydrodynamics (MHD), as appropriate in situations where the Alfvén velocity approaches the speed of light. It is found that the linear phase of the instability closely matches the analysis in classical MHD, where the growth rate scales with the Lundquist number S as S-1/2, with the only exception of an enhanced inertial term due to the thermal and magnetic energy contributions. In addition, when thin current sheets of inverse aspect ratio scaling as S-1/3 are considered, the so-called ideal tearing regime is retrieved, with modes growing independently of S and extremely fast, on only a few light crossing times of the sheet length. The overall growth of fluctuations is seen to solely depend on the value of the background Alfvén velocity. In the fully non-linear stage, we observe an inverse cascade towards the fundamental mode, with Petschek-type supersonic jets propagating at the external Alfvén speed from the X-point, and a fast reconnection rate at the predicted value {R}˜ (ln S)^{-1}.

  11. Fast electron heating of dense plasma relevant to shock ignition

    NASA Astrophysics Data System (ADS)

    Fox, T. E.; Robinson, A. P. L.; Pasley, J.

    2013-10-01

    With an intensity in the range of 1016 W/cm2, the ignitor pulse in shock-ignition inertial confinement fusion is well above the threshold of parametric instabilities. Simulations (e.g. Klimo et al. 2011 Phys. Plasmas 18, 082709) indicate that a significant amount of energy will be deposited in energetic electrons with energies <100 keV and it has been proposed that these may play a beneficial role in enhancing the ignitor shock. Simulations by Gus'kov et al. (Phys. Rev. Lett. 109, 255004 (2012)) show that, under shock-ignition relevant conditions, a mono-energetic electron beam can drive strong shocks in a uniform plasma. We extend this study to the more realistic case of a Maxwellian energy distribution in the fast electron population. Having a distribution of electron mean-free-paths results in a more extended heating profile compared to a mono-energetic beam. However, we show it is still possible to launch strong shocks in this more realistic scenario and achieve equivalent pressures. The peak pressures achieved compare well with analytic scalings. We thank AWE for their financial assistance in support of the doctoral research of T. E. F.

  12. [Age and sex variations of HbA(1C) in a French population without known diabetes aged 6 to 79 years].

    PubMed

    Gusto, Gaëlle; Vol, Sylviane; Born, Catherine; Balkau, Beverley; Lamy, Jocelyne; Bourderioux, Christiane; Lantieri, Olivier; Tichet, Jean

    2011-01-01

    HbA(1C) is being used for screening and diagnosing diabetes. We determined mean values of HbA(1C) according to age and sex in a large population without known diabetes, in a wide age range 6-79  years. 5,138 men and women without known diabetes aged 6-79  years participated in a routine health examination provided by their medical insurance. HbA(1C) was assessed on an HPLC analyzer aligned with a DCCT method. HbA(1C) was approximately normally distributed in both men and women. Mean (SD) HbA(1C) were, for men vs women, in percentages 5.3 (0.4) vs 5.2 (0.3), in mmol/mol 34 (5) vs 34 (4) and in estimated blood glucose in mmol/L 5.83 (0.67) vs 5.75 (0.53). HbA(1C) increased with age by 0.08% every 10  years and this was attenuated to a 0.04% increase after adjustment on fasting plasma glucose. Between 15 and 49  years, women had lower values than men (p < 0.0001), but no sex differences were observed before and after this age range. In our population, 0.6% had HbA(1C) greater or equal to 6.5% and 88% (96% of men and 73% of women) of them had fasting plasma glucose greater or equal to 6,1 mmol/L. Threshold of 6.0% selected 2.8% of our population.

  13. Effects of sex, age, and fasting conditions on plasma lipidomic profiles of fasted Sprague-Dawley rats.

    PubMed

    Saito, Kosuke; Ishikawa, Masaki; Murayama, Mayumi; Urata, Masayo; Senoo, Yuya; Toyoshima, Katsuko; Kumagai, Yuji; Maekawa, Keiko; Saito, Yoshiro

    2014-01-01

    Circulating lipid molecules reflect biological processes in the body and, thus, are useful tools for preclinical estimation of the efficacy and safety of newly developed drugs. However, background information on profiles of circulating lipid molecules in preclinical animal models is limited. Therefore, we examined the effects of multiple factors such as sex (fasted male vs. female), age (fasted 10 vs. 30 weeks old), and feeding conditions (feeding vs. fasting, 16 vs. 22 hr fasting, 10 AM vs. 4 PM blood collection), on the global profiles of lipid molecules in plasma from Sprague-Dawley rats by using a lipidomic approach. Our assay platform determined 262 lipid molecules (68 phospholipids, 20 sphingolipids, 138 neutral lipids, and 36 polyunsaturated fatty acids and their metabolites) in rat plasma. Multivariate discriminant analysis (orthogonal partial least squares discriminant analysis) and heat maps of statistically significant lipid molecules revealed that the plasma lipid profiles in rats are predominantly influenced by feeding conditions, followed by sex and age. In addition, the fasting duration (16 vs. 22 hr fasting) or the time of blood collection (10 AM vs. 4 PM blood collection) has limited or no contribution on the profiles of lipid molecules in rat plasma. Our results provide useful, fundamental information for exploring and validating biomarkers in future preclinical studies and may help to establish regulatory standards for such studies.

  14. Serum Uric Acid Levels were Dynamically Coupled with Hemoglobin A1c in the Development of Type 2 Diabetes

    NASA Astrophysics Data System (ADS)

    Wei, Fengjiang; Chang, Baocheng; Yang, Xilin; Wang, Yaogang; Chen, Liming; Li, Wei-Dong

    2016-06-01

    The aim of the study was to decipher the relationship between serum uric acid (SUA) and glycated hemoglobin A1c (HbA1c) or fasting plasma glucose (FPG) in both type 2 diabetes mellitus (T2DM) patients and normal subjects. A total of 2,250 unrelated T2DM patients and 4,420 Han Chinese subjects from a physical examination population were recruited for this study. In T2DM patients SUA levels were negatively correlated with HbA1c (rs = ‑0.109, P = 0.000) and 2 h plasma glucose levels (rs = ‑0.178, P = 0.000). In the physical examination population, SUA levels were inversely correlated with HbA1c (rs = ‑0.175, P = 0.000) and FPG (rs = ‑0.131, P = 0.009) in T2DM patients but positively correlated with HbA1c (rs = 0.040, P = 0.012) and FPG (rs = 0.084, P = 0.000) in normal-glucose subjects. Multivariate analyses showed that HbA1c was significantly negatively associated with HUA both in T2DM patients (OR = 0.872, 95% CI: 0.790~0.963) and in the physical examination T2DM patients (OR = 0.722, 95% CI: 0.539~0.968). Genetic association studies in T2DM patients showed that alleles of two glucose-uric acid transporter genes, ABCG2 and SLC2A9 were significantly associated with SUA levels (P < 0.05). SUA level is inversely correlated with HbA1c in T2DM patients but positively correlated with HbA1c in normal-glucose subjects. The reverse transporting of uric acid and glucose in renal tubules might be accounted for these associations.

  15. Fast Plasma Instrument for MMS: Data Compression Simulation Results

    NASA Astrophysics Data System (ADS)

    Barrie, A.; Adrian, M. L.; Yeh, P.; Winkert, G.; Lobell, J.; Vinas, A. F.; Simpson, D. G.

    2009-12-01

    Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. To meet these requirements, the Fast Plasma Instrument (FPI) consists of eight (8) identical half top-hat electron sensors and eight (8) identical ion sensors and an Instrument Data Processing Unit (IDPU). The sensors (electron or ion) are grouped into pairs whose 6° x 180° fields-of-view (FOV) are set 90° apart. Each sensor is equipped with electrostatic aperture steering to allow the sensor to scan a 45° x 180° fan about the its nominal viewing (0° deflection) direction. Each pair of sensors, known as the Dual Electron Spectrometer (DES) and the Dual Ion Spectrometer (DIS), occupies a quadrant on the MMS spacecraft and the combination of the eight electron/ion sensors, employing aperture steering, image the full-sky every 30-ms (electrons) and 150-ms (ions), respectively. To probe the diffusion regions of reconnection, the highest temporal/spatial resolution mode of FPI results in the DES complement of a given spacecraft generating 6.5-Mb s-1 of electron data while the DIS generates 1.1-Mb s-1 of ion data yielding an FPI total data rate of 6.6-Mb s-1. The FPI electron/ion data is collected by the IDPU then transmitted to the Central Data Instrument Processor (CIDP) on the spacecraft for science interest ranking. Only data sequences that contain the greatest amount of temporal/spatial structure will be intelligently down-linked by the spacecraft. Currently, the FPI data rate allocation to the CIDP is 1.5-Mb s-1. Consequently, the FPI-IDPU must employ data/image compression to meet this CIDP telemetry allocation. Here, we present updated simulations of the CCSDS 122.0-B-1 algorithm-based compression of the FPI-DES electron data as well as the FPI-DIS ion data. Compression analysis is based upon a seed of re-processed Cluster

  16. Measuring the plasma environment at Mercury: The fast imaging plasma spectrometer

    NASA Astrophysics Data System (ADS)

    Koehn, P. L.; Zurbuchen, T. H.; Gloeckler, G.; Lundgren, R. A.; Fisk, L. A.

    2002-09-01

    The plasma environment at Mercury is a rich laboratory for studying the interaction of the solar wind with a planet. Three primary populations of ions exist at Mercury: solar wind, magnetospheric and pickup ions. These pickup ions are generated through the ionization of Mercury's exosphere or are sputtered particles from the Mercury surface. A comprehensive mission to Mercury, such as MESSENGER, should include a sensor that is able to determine the dynamical properties and composition of all these plasma components. An instrument to measure the composition of these ion populations and their three dimensional velocity distribution functions must be lightweight, fast, and have a very large field of view. The Fast Imaging Plasma Spectrometer (FIPS) is an imaging mass spectrometer, part of NASA's MESSENGER mission, the first Mercury orbiter. This versatile instrument has a very small footprint, and has a mass that is about one order of magnitude less than other comparable systems. It maintains a nearly full-hemisphere field of view, suitable for either spinning or three-axis-stabilized platforms. The major piece of innovation to enable this sensor is a new deflection system geometry that enables a large instantaneous (~1.5() field of view. This novel electrostatic analyzer system is then combined with a position sensitive time-of-flight system. We discuss the design and prototype tests of the FIPS deflection system and show how this system is expected to address one key problem in Mercury science, that of the nature of the radar-bright regions at the Hermean poles.

  17. Plasma turbulence measured with fast frequency swept reflectometry in JET H-mode plasmas

    NASA Astrophysics Data System (ADS)

    Clairet, F.; Sirinelli, A.; Meneses, L.; Contributors, JET

    2016-12-01

    In this work we present recent achievements to provide precise measurements of turbulence on JET H-mode plasmas using frequency sweeping reflectometry diagnostic. The plasma density fluctuations retrieved from swept reflected signals, first initiated with the Tore Supra reflectometry (Heuraux et al 2003 Rev. Sci. Instrum. 74 1501, Vermare et al 2006 Nucl. Fusion 46 S743, Gerbaud et al 2006 Rev. Sci. Instrum. 77 10E928), provides a radial profile of the density fluctuation level and its spectral structure. Using the complete set of the JET X-mode fast sweeping heterodyne reflectometers we have determined the temporal dynamic of the density fluctuation profile from the edge to the center during an H-mode discharge. At the L-H transition, the turbulence reduction seems to occur, at first, simultaneously from the edge to the center then deepens at the edge at ρ ~ 0.95 and this deepening propagates toward the center with a steepening of the wavenumber spectra. During an edge localized mode (ELM) event, a substantial density fluctuations increase has been observed with a localized turbulent wave front propagating toward the center accompanying a particle transport. We also show that type-III ELMs sustain a steady and high level of plasma turbulence compare to type-I.

  18. GLYCATED ALBUMIN AT 4 WEEKS CORRELATES WITH A1C LEVELS AT 12 WEEKS AND REFLECTS SHORT-TERM GLUCOSE FLUCTUATIONS

    PubMed Central

    Desouza, Cyrus V.; Rosenstock, Julio; Zhou, Rong; Holcomb, Richard G.; Fonseca, Vivian A.

    2016-01-01

    Objective Evaluate the performance of glycated albumin (GA) monitoring by comparing it to other measures of glycemic control during intensification of antidiabetic therapy. Methods This 12-week, prospective, multicenter study compared the diagnostic clinical performance of GA to glycated hemoglobin A1C (A1C), fructosamine corrected for albumin (FRA), fasting plasma glucose (FPG), and mean blood glucose (MBG) estimated from self-monitoring of blood glucose (SMBG) and continuous glucose monitoring (CGM) in 30 patients with suboptimally controlled type 1 or 2 diabetes. Results Mean A1C decreased from 9.5% to 8.1%. Mean SMBG correlated closely with CGM (Pearson r = 0.783 for daily estimates and r = 0.746 for weekly estimates, P<.0001). Both GA and FRA levels significantly correlated with changes from baseline in A1C and mean weekly SMBG (P<.001).The lowest observed median GA occurred at 4 weeks, followed by a small increase and then a slight reduction, mirroring changes in overall mean SMBG values. The median A1C fell throughout the treatment period, failing to reflect short-term changes in SMBG. A ≥1% reduction in GA at 4 weeks was significantly associated with a ≥0.5% change in A1C at 12 weeks (odds ratio [OR] = 19.0, 95% confidence interval [CI]: 1.4, 944, P = .018). Conclusion In patients receiving glucose-lowering therapy, changes in GA at 4 weeks were concordant with changes in A1C at 12 weeks, and both GA and FRA more accurately reflected short-term blood glucose fluctuations than A1C. PMID:26214108

  19. Does Iron Deficiency Anaemia and its Severity Influence HbA1C Level in Non Diabetics? An Analysis of 150 Cases

    PubMed Central

    Ganapathy, Shivashekar; Arunachalam, Sundaram; Raja, Veena; Ramraj, Balaji

    2017-01-01

    Introduction Anaemia has a high prevalence having great impact worldwide and potentially contributing to the pathogenesis of various chronic diseases. Approximately 1/3rd of patients with anaemia have iron deficiency. American Diabetes Association (ADA) has affirmed Glycated Haemoglobin (HbA1C) ≥ 6.5% as a diagnostic criterion for Diabetes Mellitus (DM). Variation of HbA1C in Iron Deficiency Anaemia (IDA) has clashing results. Aim To decide the impact of IDA on HbA1C levels among non diabetics. To assess and analyse the variation of HbA1C according to the degree of anaemia (mild, moderate and severe). Materials and Methods This cross-sectional study was carried out in SRM Medical College Hospital and Research Centre, Chennai, Tamil Nadu from February 2016 to October 2016 and approved by our Institutional Ethical Committee. Totally 150 non diabetics (75 with IDA and 75 without IDA) were included in this study. Medical history was recorded and HbA1C, Haemoglobin (Hb), Haematocrit (Hct), red cell indices, serum iron, ferritin and Fasting Plasma Glucose (FPG) were tested. Results The IDA patients in this study had a mean HbA1C (6.84±0.07%) which was higher than the non anaemic group (5.12±0.04%) and this difference was statistically significant (p< 0.05). HbA1C level was increased when severity of anaemia worsened. Also, noteworthy statistical significance was observed between no anaemia, mild, moderate and severe anaemia (p< 0.05). Conclusion In this study, we observed a positive correlation between IDA and elevated HbA1C level in non-diabetic population.

  20. Spectroscopic interpretation and velocimetry analysis of fluctuations in a cylindrical plasma recorded by a fast camera

    SciTech Connect

    Oldenbuerger, S.; Brandt, C.; Brochard, F.; Lemoine, N.; Bonhomme, G.

    2010-06-15

    Fast visible imaging is used on a cylindrical magnetized argon plasma produced by thermionic discharge in the Mirabelle device. To link the information collected with the camera to a physical quantity, fast camera movies of plasma structures are compared to Langmuir probe measurements. High correlation is found between light fluctuations and plasma density fluctuations. Contributions from neutral argon and ionized argon to the overall light intensity are separated by using interference filters and a light intensifier. Light emitting transitions are shown to involve a metastable neutral argon state that can be excited by thermal plasma electrons, thus explaining the good correlation between light and density fluctuations. The propagation velocity of plasma structures is calculated by adapting velocimetry methods to the fast camera movies. The resulting estimates of instantaneous propagation velocity are in agreement with former experiments. The computation of mean velocities is discussed.

  1. Fast Plasma Instrument for MMS: Data Compression Simulation Results

    NASA Technical Reports Server (NTRS)

    Barrie, A.; Adrian, Mark L.; Yeh, P.-S.; Winkert, G. E.; Lobell, J. V.; Vinas, A.F.; Simpson, D. J.; Moore, T. E.

    2008-01-01

    Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. To meet these requirements, the Fast Plasma Instrument (FPI) consists of eight (8) identical half top-hat electron sensors and eights (8) identical ion sensors and an Instrument Data Processing Unit (IDPU). The sensors (electron or ion) are grouped into pairs whose 6 deg x 180 deg fields-of-view (FOV) are set 90 deg apart. Each sensor is equipped with electrostatic aperture steering to allow the sensor to scan a 45 deg x 180 deg fan about its nominal viewing (0 deg deflection) direction. Each pair of sensors, known as the Dual Electron Spectrometer (DES) and the Dual Ion Spectrometer (DIS), occupies a quadrant on the MMS spacecraft and the combination of the eight electron/ion sensors, employing aperture steering, image the full-sky every 30-ms (electrons) and 150-ms (ions), respectively. To probe the results in the DES complement of a given spacecraft generating 6.5-Mbs(exp -1) of electron data while the DIS generates 1.1-Mbs(exp -1) of ion data yielding an FPI total data rate of 6.6-MBs(exp -1). The FPI electron/ion data is collected by the IDPU then transmitted to the Central Data Instrument Processor (CIDP) on the spacecraft for science interest ranking. Only data sequences that contain the greatest amount of temporal/spatial structure will be intelligently down-linked by the spacecraft. Currently, the FPI data rate allocation to the CIDP is 1.5-Mbs(exp -1). Consequently, the FPI-IDPU must employ data/image compression to meet this CIDP telemetry allocation. Here, we present simulations of the CCSDS 122.0-B-1 algorithm-based compression of the FPI-DES electron data. Compression analysis is based upon a seed of re-processed Cluster/PEACE electron measurements. Topics to be discussed include: review of compression algorithm; data quality

  2. Fast Plasma Instrument for MMS: Data Compression Simulation Results

    NASA Astrophysics Data System (ADS)

    Barrie, A. C.; Adrian, M. L.; Yeh, P.; Winkert, G. E.; Lobell, J. V.; Viňas, A. F.; Simpson, D. G.; Moore, T. E.

    2008-12-01

    Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. To meet these requirements, the Fast Plasma Instrument (FPI) consists of eight (8) identical half top-hat electron sensors and eight (8) identical ion sensors and an Instrument Data Processing Unit (IDPU). The sensors (electron or ion) are grouped into pairs whose 6° × 180° fields-of-view (FOV) are set 90° apart. Each sensor is equipped with electrostatic aperture steering to allow the sensor to scan a 45° × 180° fan about the its nominal viewing (0° deflection) direction. Each pair of sensors, known as the Dual Electron Spectrometer (DES) and the Dual Ion Spectrometer (DIS), occupies a quadrant on the MMS spacecraft and the combination of the eight electron/ion sensors, employing aperture steering, image the full-sky every 30-ms (electrons) and 150-ms (ions), respectively. To probe the diffusion regions of reconnection, the highest temporal/spatial resolution mode of FPI results in the DES complement of a given spacecraft generating 6.5-Mb s-1 of electron data while the DIS generates 1.1-Mb s-1 of ion data yielding an FPI total data rate of 7.6-Mb s-1. The FPI electron/ion data is collected by the IDPU then transmitted to the Central Data Instrument Processor (CIDP) on the spacecraft for science interest ranking. Only data sequences that contain the greatest amount of temporal/spatial structure will be intelligently down-linked by the spacecraft. Currently, the FPI data rate allocation to the CIDP is 1.5-Mb s-1. Consequently, the FPI-IDPU must employ data/image compression to meet this CIDP telemetry allocation. Here, we present simulations of the CCSDS 122.0-B-1 algorithm- based compression of the FPI-DES electron data. Compression analysis is based upon a seed of re- processed Cluster/PEACE electron measurements. Topics to be

  3. Fast magnetic field penetration into low resistivity plasma

    NASA Astrophysics Data System (ADS)

    Fruchtman, Amnon

    2017-02-01

    Penetration of a magnetic field into plasma that is faster than resistive diffusion can be induced by the Hall electric field in a non-uniform plasma. This mechanism explained successfully the measured velocity of the magnetic field penetration into pulsed plasmas. Major related issues have not yet been resolved. Such is the theoretically predicted, but so far not verified experimentally, high magnetic energy dissipation, as well as the correlation between the directions of the density gradient and of the field penetration.

  4. Methods, units and quality requirements for the analysis of haemoglobin A1c in diabetes mellitus

    PubMed Central

    Penttilä, Ilkka; Penttilä, Karri; Holm, Päivi; Laitinen, Harri; Ranta, Päivi; Törrönen, Jukka; Rauramaa, Rainer

    2016-01-01

    The formation of glycohemoglobin, especially the hemoglobin A1c (HbA1c) fraction, occurs when glucose becomes coupled with the amino acid valine in the β-chain of Hb; this reaction is dependent on the plasma concentration of glucose. Since the early 1970s it has been known that diabetics display higher values OF HbA1C because they have elevated blood glucose concentrations. Thus HbA1c has acquired a very important role in the treatment and diagnosis of diabetes mellitus. After the introduction of the first quantitative measurement OF HbA1C, numerous methods for glycohemoglobin have been introduced with different assay principles: From a simple mini-column technique to the very accurate automated high-pressure chromatography and lastly to many automated immunochemical or enzymatic assays. In early days, the results of the quality control reports for HbA1c varied extensively between laboratories, therefore in United States and Canada working groups (WG) of the Diabetes Controls and Complications Trial (DCCT) were set up to standardize the HbA1c assays against the DCCT/National Glycohemoglobin Standardization Program reference method based on liquid chromatography. In the 1990s, the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) appointed a new WG to plan a reference preparation and method for the HBA1c measurement. When the reference procedures were established, in 2004 IFCC recommended that all manufacturers for equipment used in HbA1c assays should calibrate their methods to their proposals. This led to an improvement in the coefficient of variation (CV%) associated with the assay. In this review, we describe the glycation of Hb, methods, standardization of the HbA1c assays, analytical problems, problems with the units in which HbA1c values are expressed, reference values, quality control aspects, target requirements for HbA1c, and the relationship of the plasma glucose values to HbA1c concentrations. We also note that the acceptance

  5. Methods, units and quality requirements for the analysis of haemoglobin A1c in diabetes mellitus.

    PubMed

    Penttilä, Ilkka; Penttilä, Karri; Holm, Päivi; Laitinen, Harri; Ranta, Päivi; Törrönen, Jukka; Rauramaa, Rainer

    2016-06-26

    The formation of glycohemoglobin, especially the hemoglobin A1c (HbA1c) fraction, occurs when glucose becomes coupled with the amino acid valine in the β-chain of Hb; this reaction is dependent on the plasma concentration of glucose. Since the early 1970s it has been known that diabetics display higher values OF HbA1C because they have elevated blood glucose concentrations. Thus HbA1c has acquired a very important role in the treatment and diagnosis of diabetes mellitus. After the introduction of the first quantitative measurement OF HbA1C, numerous methods for glycohemoglobin have been introduced with different assay principles: From a simple mini-column technique to the very accurate automated high-pressure chromatography and lastly to many automated immunochemical or enzymatic assays. In early days, the results of the quality control reports for HbA1c varied extensively between laboratories, therefore in United States and Canada working groups (WG) of the Diabetes Controls and Complications Trial (DCCT) were set up to standardize the HbA1c assays against the DCCT/National Glycohemoglobin Standardization Program reference method based on liquid chromatography. In the 1990s, the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) appointed a new WG to plan a reference preparation and method for the HBA1c measurement. When the reference procedures were established, in 2004 IFCC recommended that all manufacturers for equipment used in HbA1c assays should calibrate their methods to their proposals. This led to an improvement in the coefficient of variation (CV%) associated with the assay. In this review, we describe the glycation of Hb, methods, standardization of the HbA1c assays, analytical problems, problems with the units in which HbA1c values are expressed, reference values, quality control aspects, target requirements for HbA1c, and the relationship of the plasma glucose values to HbA1c concentrations. We also note that the acceptance

  6. Heating a plasma by a broadband stream of fast electrons: Fast ignition, shock ignition, and Gbar shock wave applications

    SciTech Connect

    Gus’kov, S. Yu.; Nicolai, Ph.; Ribeyre, X.; Tikhonchuk, V. T.

    2015-09-15

    An exact analytic solution is found for the steady-state distribution function of fast electrons with an arbitrary initial spectrum irradiating a planar low-Z plasma with an arbitrary density distribution. The solution is applied to study the heating of a material by fast electrons of different spectra such as a monoenergetic spectrum, a step-like distribution in a given energy range, and a Maxwellian spectrum, which is inherent in laser-produced fast electrons. The heating of shock- and fast-ignited precompressed inertial confinement fusion (ICF) targets as well as the heating of a target designed to generate a Gbar shock wave for equation of state (EOS) experiments by laser-produced fast electrons with a Maxwellian spectrum is investigated. A relation is established between the energies of two groups of Maxwellian fast electrons, which are responsible for generation of a shock wave and heating the upstream material (preheating). The minimum energy of the fast and shock igniting beams as well as of the beam for a Gbar shock wave generation increases with the spectral width of the electron distribution.

  7. Gas dynamic theory of flight of fast electron flux in plasma

    NASA Astrophysics Data System (ADS)

    Melnik, V. N.

    The one-dimensional flight of a fast electron flux in plasma is investigated taking into account generation and absorption of plasma waves. The transition from the kinetic description to the gas dynamics is made. The closed set of gas dynamic equations for electrons and plasmons is derived and an automodel solution is obtained in the case of instantaneous injection. This solution represents the beam-plasma formation on natural oscillations in the system electrons+plasmons is considered.

  8. Optical emission spectroscopy observations of fast pulsed capillary discharge plasmas

    NASA Astrophysics Data System (ADS)

    Avaria, G.; Ruiz, M.; Guzmán, F.; Favre, M.; Wyndham, E. S.; Chuaqui, H.; Bhuyan, H.

    2014-05-01

    We present time resolved optical emission spectroscopic (OES) observations of a low energy, pulsed capillary discharage (PCD). The optical emission from the capillary plasma and plasma jets emitted from the capillary volume was recorded with with a SpectraPro 275 spectrograph, fitted with a MCP gated OMA system, with 15 ns time resolution. The discharge was operated with different gases, including argon, nitrogen, hydrogen and methane, in a repetitive pulsed discharge mode at 10-50 Hz, with, 10-12 kV pulses applied at the cathode side. The time evolution of the electron density was measured using Stark broadening of the Hβ line. Several features of the capillary plasma dynamics, such as ionization growth, wall effects and plasma jet evolution, are inferred from the time evolution of the optical emission.

  9. Dynamical programming based turbulence velocimetry for fast visible imaging of tokamak plasma

    NASA Astrophysics Data System (ADS)

    Banerjee, Santanu; Zushi, H.; Nishino, N.; Mishra, K.; Onchi, T.; Kuzmin, A.; Nagashima, Y.; Hanada, K.; Nakamura, K.; Idei, H.; Hasegawa, M.; Fujisawa, A.

    2015-03-01

    An orthogonal dynamic programming (ODP) based particle image velocimetry (PIV) technique is developed to measure the time resolved flow field of the fluctuating structures at the plasma edge and scrape off layer (SOL) of tokamaks. This non-intrusive technique can provide two dimensional velocity fields at high spatial and temporal resolution from a fast framing image sequence and hence can provide better insights into plasma flow as compared to conventional probe measurements. Applicability of the technique is tested with simulated image pairs. Finally, it is applied to tangential fast visible images of QUEST plasma to estimate the SOL flow in inboard poloidal null-natural divertor configuration. This technique is also applied to investigate the intricate features of the core of the run-away dominated phase following the injection of a large amount of neutrals in the target Ohmic plasma. Development of the ODP-PIV code and its applicability on actual plasma images is reported.

  10. Emission of fast non-Maxwellian hydrogen atoms in low-density laboratory plasma

    NASA Astrophysics Data System (ADS)

    Brandt, Christian; Marchuk, Oleksandr; Pospieszczyk, Albrecht; Dickheuer, Sven

    2017-03-01

    The source of strong and broad emission of the Balmer-α line in mixed plasmas of hydrogen (or deuterium) and noble gases in front of metallic surfaces is a subject of controversial discussion of many plasma types. In this work the excitation source of the Balmer lines is investigated by means of optical emission spectroscopy in the plasma device PSI-2. Neutral fast non-Maxwellian hydrogen atoms are produced by acceleration of hydrogen ions towards an electrode immersed into the plasma. By variation of the electrode potential the energy of ions and in turn of reflected fast atoms can be varied in the range of 40-300 eV. The fast atoms in front of the electrode are observed simultaneously by an Echelle spectrometer (0.001 nm/channel) and by an imaging spectrometer (0.01 nm/channel) up to few cm in the plasma. Intense excitation channels of the Balmer lines are observed when hydrogen is mixed with argon or with krypton. Especially in Ar-H and Ar-D mixed plasmas the emission of fast hydrogen atoms is very strong. Intermixing hydrogen with other noble gases (He, Ne or Xe) one observes the same effect however the emission is one order of magnitude less compared to Kr-H or Kr-D plasmas. It is shown, that the key process, impacting this emission, is the binary collision between the fast neutral hydrogen atom and the noble gas atom. Two possible sources of excitation are discussed in details: one is the excitation of hydrogen atoms by argon atoms in the ground state and the second one is the process of the so-called excitation transfer between the metastable states of noble gases and hydrogen. In the latter case the atomic data for excitation of Balmer lines are still not available in literature. Further experimental investigations are required to conclude on the source process of fast atom emission.

  11. Fast electron generation and transport in a turbulent, magnetized plasma

    SciTech Connect

    Stoneking, Matthew Randall

    1994-05-01

    The nature of fast electron generation and transport in the Madison Symmetric Torus (MST) reversed field pinch (RFP) is investigated using two electron energy analyzer (EEA) probes and a thermocouple calorimeter. The parallel velocity distribution of the fast electron population is well fit by a drifted Maxwellian distribution with temperature of about 100 eV and drift velocity of about 2 x 106 m/s. Cross-calibration of the EEA with the calorimeter provides a measurement of the fast electron perpendicular temperature of 30 eV, much lower than the parallel temperature, and is evidence that the kinetic dynamo mechanism (KDT) is not operative in MST. The fast electron current is found to match to the parallel current at the edge, and the fast electron density is about 4 x 1011 cm-3 independent of the ratio of the applied toroidal electric field to the critical electric field for runaways. First time measurements of magnetic fluctuation induced particle transport are reported. By correlating electron current fluctuations with radial magnetic fluctuations the transported flux of electrons is found to be negligible outside r/a~0.9, but rises the level of the expected total particle losses inside r/a~0.85. A comparison of the measured diffusion coefficient is made with the ausilinear stochastic diffusion coefficient. Evidence exists that the reduction of the transport is due to the presence of a radial ambipolar electric field of magnitude 500 V/m, that acts to equilibrate the ion and electron transport rates. The convective energy transport associated with the measured particle transport is large enough to account for the observed magnetic fluctuation induced energy transport in MST.

  12. Communication through a plasma sheet around a fast moving vehicle

    NASA Astrophysics Data System (ADS)

    Sotnikov, V. I.; Mudaliar, S.; Genoni, T.; Rose, D.; Oliver, B. V.; Mehlhorn, T. A.

    2011-10-01

    Investigation of the complicated problem of scattering of electromagnetic waves on turbulent pulsations induced by a sheared flow inside a plasma sheath is important for many applications including communication with hypersonic and re-entry vehicles. Theoretical and computational work aimed at improving the understanding of electromagnetic wave scattering processes in such turbulent plasmas is presented. We analyze excitation of low frequency ion-acoustic type oscillations in a compressible plasma flow with flow velocity shear and influence of such turbulent pulsations on scattering of high frequency electromagnetic waves used for communication purposes. We have appropriately included in our analysis the presence of electron and ion collisions with neutrals as well as electron - ion collisions. Results of numerical solutions for plasma density and electric field perturbations for different velocity profiles have been used in the derived expressions for scattered wave energy and scattering cross section. Work supported by the Air Force Research Laboratory and Air Force Office Of Scientific Research Sandia is a multiprogram laboratory operated by Sandia Corporation, A Lockheed Martin Company, under contract DE-AC04-94AL85000.

  13. Fast figuring of large optics by reactive atom plasma

    NASA Astrophysics Data System (ADS)

    Castelli, Marco; Jourdain, Renaud; Morantz, Paul; Shore, Paul

    2012-09-01

    The next generation of ground-based astronomical observatories will require fabrication and maintenance of extremely large segmented mirrors tens of meters in diameter. At present, the large production of segments required by projects like E-ELT and TMT poses time frames and costs feasibility questions. This is principally due to a bottleneck stage in the optical fabrication chain: the final figuring step. State-of-the-art figure correction techniques, so far, have failed to meet the needs of the astronomical community for mass production of large, ultra-precise optical surfaces. In this context, Reactive Atom Plasma (RAP) is proposed as a candidate figuring process that combines nanometer level accuracy with high material removal rates. RAP is a form of plasma enhanced chemical etching at atmospheric pressure based on Inductively Coupled Plasma technology. The rapid figuring capability of the RAP process has already been proven on medium sized optical surfaces made of silicon based materials. In this paper, the figure correction of a 3 meters radius of curvature, 400 mm diameter spherical ULE mirror is presented. This work demonstrates the large scale figuring capability of the Reactive Atom Plasma process. The figuring is carried out by applying an in-house developed procedure that promotes rapid convergence. A 2.3 μm p-v initial figure error is removed within three iterations, for a total processing time of 2.5 hours. The same surface is then re-polished and the residual error corrected again down to λ/20 nm rms. These results highlight the possibility of figuring a metre-class mirror in about ten hours.

  14. First experimental demonstration of magnetic-field assisted fast heating of a dense plasma core

    NASA Astrophysics Data System (ADS)

    Fujioka, Shinsuke; Sakata, Shohei; Lee, Seung Ho; Matsuo, Kazuki; Sawada, Hiroshi; Iwasa, Yuki; Law, King Fai Farley; Morita, Hitoki; Kojima, Sadaoki; Abe, Yuki; Yao, Akira; Hata, Masayasu; Johzaki, Tomoyuki; Sunahara, Atsushi; Ozaki, Tetsuo; Sakagami, Hitoshi; Morace, Alessio; Arikawa, Yasunobu; Yogo, Akifumi; Nishimura, Hiroaki; Nakai, Mitsuo; Shiraga, Hiroyuki; Sentoku, Yasuhiko; Nagatomo, Hideo; Azechi, Hiroshi; Firex Project Team

    2016-10-01

    Fast heating of a dense plasma core by an energetic electron beam is being studied on GEKKO-LFEX laser facility. Here, we introduce a laser-driven kilo-tesla external magnetic field to guide the diverging electron beam to the dense plasma core. This involve placing a spherical target in the magnetic field, compressing it with the GEKKO-XII laser beams and then using the LFEX laser beams injected into the dense plasma to generate the electron beam which do the fast heating. Cu-Ka emission is used to visualize transport or heating processes of a dense plasma. X-ray spectrum from a highly ionized Cu ions indicates several keV of the temperature increment induced by the LFEX.

  15. Elevated Fasting Plasma Glucose before Liver Transplantation is Associated with Lower Post-Transplant Survival

    PubMed Central

    Katsura, Emi; Ichikawa, Tatsuki; Taura, Naota; Miyaaki, Hisamitsu; Miuma, Satoshi; Shibata, Hidetaka; Honda, Takuya; Hidaka, Masaaki; Soyama, Akihiko; Takeshima, Fuminao; Eguchi, Susumu; Nakao, Kazuhiko

    2016-01-01

    Background The risk of liver cirrhosis is higher among individuals with diabetes mellitus, and a cirrhotic patient with diabetes may have a poorer prognosis after liver transplantation compared to a patient without diabetes. Thus, we evaluated whether fasting plasma glucose prior to receiving a liver transplant was a prognostic factor for post-transplant survival. Material/Methods Ninety-one patients received a living donor liver transplant between November 2005 and December 2012. Patients were considered diabetic if they were prescribed diabetes medications or had impaired glucose tolerance as measured by an oral glucose tolerance test. Each patient was monitored through December 31, 2013, to evaluate prognosis. Results Fasting plasma glucose of at least 100 mg/dL significantly decreased survival following transplant (52% in the high FPG group compared to 78% in the control group, p=0.04), while postprandial hyperglycemia had no effect on survival. Additionally, overall mortality and the incidence of vascular disease were significantly higher among patients with uncontrolled plasma glucose. Impaired fasting plasma glucose was significantly and inversely associated with overall survival in the univariate and multivariate analyses, while creatinine (at least 1 mg/dL) was inversely associated with survival in the univariate analysis. Conclusions Elevated fasting plasma glucose prior to liver transplantation was inversely associated with post-transplant survival. This effect may be due to underlying microangiopathy as a result of uncontrolled diabetes before transplantation. Our data demonstrated the importance of controlled blood glucose prior to liver transplantation. PMID:27909287

  16. Association between Alcohol Intake and Hemoglobin A1c in the Korean Adults: The 2011-2013 Korea National Health and Nutrition Examination Survey

    PubMed Central

    Hong, Jae Won; Noh, Jung Hyun; Kim, Dong-Jun

    2016-01-01

    Background Although alcohol consumption is commonly encountered in clinical practice, few studies have investigated the clinical significance of alcohol intake on the use of the hemoglobin A1c (HbA1c) level. Objectives This study was performed to investigate the association between alcohol intake and HbA1c level in the general population. Methods Among the 24,594 participants who participated in the 2011–2013 Korea National Health and Nutrition Examination Survey (KNHANES), 12,923 participants were analyzed in this study. We excluded diabetic patients currently taking antidiabetes medication. We compared the HbA1c level and proportions of patients with an HbA1c level of ≥5.7%, ≥6.1%, and ≥6.5% according to the fasting plasma glucose (FPG) concentration range and the amount of alcohol intake. The average amounts of daily alcohol intake were categorized into three groups: 0 g/day, <30 g/day, ≥30 g/day. Results The mean HbA1c level was 5.65%, and the mean FPG concentration was 95.3 mg/dl. The percentages of patients with an HbA1c level of ≥5.7%, ≥6.1%, and ≥6.5% were 42.6%, 13.4%, and 4.5%, respectively. The average amount of alcohol intake was 12.3 g/day. The percentages of subjects with alcohol intake 0, <30, and ≥ 30 g/day were 16.5%, 69.7%, and 13.8%, respectively. There was a significant positive relationship between alcohol intake and FPG concentration (P < 0.001), the prevalence of impaired fasting glucose (P < 0.001), and the prevalence of diabetes (P < 0.001). However, there was no significant relationship between the alcohol intake and HbA1c level. Overall, the adjusted HbA1c levels decreased across alcohol intake (5.70% ± 0.01%, 5.66% ± 0.01%, and 5.55% ± 0.01%) after adjustment for confounding factors such as age, sex, FPG concentration, college graduation, smoking history, presence of hypertension, waist circumference, serum total cholesterol concentration, serum high-density lipoprotein cholesterol concentration, serum triglyceride

  17. Effect of chromium-enriched yeast on fasting plasma glucose, glycated haemoglobin and serum lipid levels in patients with type 2 diabetes mellitus treated with insulin.

    PubMed

    Racek, Jaroslav; Sindberg, C D; Moesgaard, S; Mainz, Josef; Fabry, Jaroslav; Müller, Luděk; Rácová, Katarína

    2013-10-01

    Chromium is required for a normal insulin function, and low levels have been linked with insulin resistance. The aim of this study was to follow the effect of chromium supplementation on fasting plasma glucose (FPG), glycated haemoglobin (HbA1c) and serum lipids in patients with type 2 diabetes mellitus (DM2) on insulin therapy. Eleven randomly selected patients with DM2 on insulin therapy were supplemented with a daily dose of 100 μg chromium yeast for the first supplementation period of 2 weeks. In the second supplementation period, the chromium dose was doubled and continued for the next 6 weeks. The third phase was a 6-week washout period. After each period, the levels of FPG and HbA1c were compared with the corresponding values at the end of the previous period. Serum triglycerides, total HDL and LDL cholesterol values after supplementation were compared with the baseline values. FPG decreased significantly after the first period of chromium supplementation (p < 0.001), and a tendency to a further reduction was observed after the second supplementation period. Similarly, HbA1c decreased significantly in both periods (p < 0.02 and p < 0.002, respectively). Eight weeks after withdrawal of chromium supplementation, both FPG and HbA1c levels returned to their pre-intervention values. The serum lipid concentrations were not significantly influenced by chromium supplementation. Chromium supplementation could be beneficial in patients with DM2 treated with insulin, most likely due to lowered insulin resistance leading to improved glucose tolerance. This finding needs to be confirmed in a larger study.

  18. Integrated Kinetic Simulation of Laser-Plasma Interactions, Fast-Electron Generation and Transport in Fast Ignition

    SciTech Connect

    Kemp, A; Cohen, B; Divol, L

    2009-11-16

    We present new results on the physics of short-pulse laser-matter interaction of kilojoule-picosecond pulses at full spatial and temporal scale, using a new approach that combines a 3D collisional electromagnetic Particle-in-Cell code with an MHD-hybrid model of high-density plasma. In the latter, collisions damp out plasma waves, and an Ohm's law with electron inertia effects neglected determines the electric field. In addition to yielding orders of magnitude in speed-up while avoiding numerical instabilities, this allows us to model the whole problem in a single unified framework: the laser-plasma interaction at sub-critical densities, energy deposition at relativistic critical densities, and fast-electron transport in solid densities. Key questions such as the multi-picosecond temporal evolution of the laser energy conversion into hot electrons, the impact of return currents on the laser-plasma interaction, and the effect of self-generated electric and magnetic fields on electron transport will be addressed. We will report applications to current experiments.

  19. Integrated kinetic simulation of laser-plasma interactions, fast-electron generation, and transport in fast ignition

    SciTech Connect

    Kemp, A. J.; Cohen, B. I.; Divol, L.

    2010-05-15

    We present new results on the physics of short-pulse laser-matter interaction of kilojoule-picosecond pulses at full spatial and temporal scale using a new approach that combines a three-dimensional collisional electromagnetic particle-in-cell code with a magnetohydrodynamic-hybrid model of high-density plasma. In the latter, collisions damp out plasma waves, and an Ohm's law with electron inertia effects neglected determines the electric field. In addition to yielding orders of magnitude in speed-up while avoiding numerical instabilities, this allows us to model the whole problem in a single unified framework: the laser-plasma interaction at subcritical densities, energy deposition at relativistic critical densities, and fast- electron transport in solid densities. Key questions such as the multipicosecond temporal evolution of the laser energy conversion into hot electrons, the impact of return currents on the laser-plasma interaction, and the effect of self-generated electric and magnetic fields on electron transport will be addressed. We will report applications to current experiments.

  20. Significance of HbA1c Test in Diagnosis and Prognosis of Diabetic Patients

    PubMed Central

    Sherwani, Shariq I.; Khan, Haseeb A.; Ekhzaimy, Aishah; Masood, Afshan; Sakharkar, Meena K.

    2016-01-01

    Diabetes is a global endemic with rapidly increasing prevalence in both developing and developed countries. The American Diabetes Association has recommended glycated hemoglobin (HbA1c) as a possible substitute to fasting blood glucose for diagnosis of diabetes. HbA1c is an important indicator of long-term glycemic control with the ability to reflect the cumulative glycemic history of the preceding two to three months. HbA1c not only provides a reliable measure of chronic hyperglycemia but also correlates well with the risk of long-term diabetes complications. Elevated HbA1c has also been regarded as an independent risk factor for coronary heart disease and stroke in subjects with or without diabetes. The valuable information provided by a single HbA1c test has rendered it as a reliable biomarker for the diagnosis and prognosis of diabetes. This review highlights the role of HbA1c in diagnosis and prognosis of diabetes patients. PMID:27398023

  1. Fast tokamak plasma flux and electron density reconstruction technique

    SciTech Connect

    Chiang, K.L.; Hallock, G.A.; Wootton, A.J.; Wang, L.

    1997-01-01

    Density profiles in TEXT-U are obtained using a vertical viewing far-infrared (FIR) interferometer. To obtain the local (inverted) density, we have developed a simple analytic model of the plasma equilibrium configuration which is faster than EFIT (a flux surface reconstruction program) and can be easily computed between discharges. This analytic solution of the Grad{endash}Shafranov equation is valid as long as the pressure p is a function of poloidal flux {psi}, i.e., p=p({psi}). The procedure incorporates both magnetic and FIR density data to solve the Grad{endash}Shafranov equation, and provides a density profile which is self-consistent with the reconstructed equilibrium flux surfaces. Examples are presented. {copyright} {ital 1997 American Institute of Physics.}

  2. A Comparison of hs-CRP Levels in New Diabetes Groups Diagnosed Based on FPG, 2-hPG, or HbA1c Criteria.

    PubMed

    Tutuncu, Yildiz; Satman, Ilhan; Celik, Selda; Dinccag, Nevin; Karsidag, Kubilay; Telci, Aysegul; Genc, Sema; Issever, Halim; Tuomilehto, Jaakko; Omer, Beyhan

    2016-01-01

    Fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) have been used to diagnose new-onset diabetes mellitus (DM) in order to simplify the diagnostic tests compared with the 2-hour oral glucose tolerance test (OGTT; 2-hPG). We aimed to identify optimal cut-off points of high sensitive C-reactive protein (hs-CRP) in new-onset DM people based on FPG, 2-hPG, or HbA1c methods. Data derived from recent population-based survey in Turkey (TURDEP-II). The study included 26,499 adult people (63% women, response rate 85%). The mean serum concentration of hs-CRP in women was higher than in men (p < 0.001). The people with new-onset DM based on HbA1c had higher mean hs-CRP level than FPG based and 2-hPG based DM cases. In HbA1c, 2-hPG, and FPG based new-onset DM people, cut-off levels of hs-CRP in women were 2.9, 2.1, and 2.5 mg/L [27.5, 19.7, and 23.5 nmol/L] and corresponding values in men were 2.0, 1.8, and 1.8 mg/L (19.0, 16.9, and 16.9 nmol/L), respectively (sensitivity 60-65% and specificity 54-64%). Our results revealed that hs-CRP may not further strengthen the diagnosis of new-onset DM. Nevertheless, the highest hs-CRP level observed in new-onset DM people diagnosed with HbA1c criterion supports the general assumption that this method might recognize people in more advanced diabetic stage compared with other diagnostic methods.

  3. Fast-acting calorimeter measures heat output of plasma gun accelerator

    NASA Technical Reports Server (NTRS)

    Dethlefson, R.; Larson, A. V.; Liebing, L.

    1967-01-01

    Calorimeter measures the exhaust energy from a shot of a pulsed plasma gun accelerator. It has a fast response time and requires only one measurement to determine the total energy. It uses a long ribbon of copper foil wound around a glass frame to form a reentrant cavity.

  4. The role of curvature and stretching on the existence of fast dynamo plasma in Riemannian space

    SciTech Connect

    Garcia de Andrade, L. C.

    2008-12-15

    Vishik's anti-dynamo theorem is applied to a nonstretched twisted magnetic flux tube in Riemannian space. Marginal or slow dynamos along curved (folded), torsioned (twisted), and nonstretching flux tubes plasma flows are obtained. Riemannian curvature of the twisted magnetic flux tube is computed in terms of the Frenet curvature in the thin tube limit. It is shown that, for nonstretched filaments, fast dynamo action in the diffusive case cannot be obtained, in agreement with Vishik's argument that fast dynamos cannot be obtained in nonstretched flows. Instead of a fast dynamo, a nonuniform stretching slow dynamo is obtained. An example is given, which generalizes plasma dynamo laminar flows, recently presented by Wang et al. [Phys Plasmas 9, 1491 (2002)], in the case of low magnetic Reynolds number Re{sub m}{>=}210. Curved and twisting Riemannian heliotrons, where nondynamo modes are found even when stretching is present, shows that the simple presence of stretching is not enough for the existence of dynamo action. In this paper, folding plays the role of Riemannian curvature and can be used to cancel magnetic fields, not enhancing the dynamo action. Nondynamo modes are found for certain values of torsion, or Frenet curvature (folding) in the spirit of the anti-dynamo theorem. It is also shown that curvature and stretching are fundamental for the existence of fast dynamos in plasmas.

  5. Diagnostic value of the rectal ammonia tolerance test, fasting plasma ammonia and fasting plasma bile acids for canine portosystemic shunting.

    PubMed

    van Straten, G; Spee, B; Rothuizen, J; van Straten, M; Favier, R P

    2015-06-01

    Portosystemic shunting (PSS) often results in hyperammonaemia and, consequently, hepatic encephalopathy. This retrospective study evaluated the sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively) and other test performance metrics for the ammonia tolerance test (ATT), serum fasting bile acids (FBA), serum fasting ammonia concentration (FA), and combinations of these tests for their association with PSS in dogs. Medical records of 271 dogs suspect for PSS (symptomatic group) and 53 dogs returning for evaluation after surgical closure of a congenital PSS (CPSS post-surgical control group) were analysed. In the symptomatic group, ATT at 40 min (T40), and the FBA had the highest sensitivity (100% and 98%, respectively) and NPV (100% and 96%, respectively) for PSS. The combination of increased FBA and FA had the highest specificity (97%), with a PPV of 97%, and a positive likelihood ratio of 29. In the CPSS post-surgical control group, the specificity and PPV of FA and the combination of increased FBA/FA were both 100%. In purebred populations, the NPV of all tests was 100%. Consequently, PSS would be ruled out in a symptomatic dog with normal FBA or ATT (T40) and would be highly probable when both FBA and FA are increased. Increased FA was conclusive for PSS in dogs evaluated for post-surgical closure of a CPSS. FBA was the most suitable test for screening purposes.

  6. Newly developed double neural network concept for reliable fast plasma position control

    NASA Astrophysics Data System (ADS)

    Jeon, Young-Mu; Na, Yong-Su; Kim, Myung-Rak; Hwang, Y. S.

    2001-01-01

    Neural network is considered as a parameter estimation tool in plasma controls for next generation tokamak such as ITER. The neural network has been reported to be so accurate and fast for plasma equilibrium identification that it may be applied to the control of complex tokamak plasmas. For this application, the reliability of the conventional neural network needs to be improved. In this study, a new idea of double neural network is developed to achieve this. The new idea has been applied to simple plasma position identification of KSTAR tokamak for feasibility test. Characteristics of the concept show higher reliability and fault tolerance even in severe faulty conditions, which may make neural network applicable to plasma control reliably and widely in future tokamaks.

  7. Intensive lifestyle intervention including high-intensity interval training program improves insulin resistance and fasting plasma glucose in obese patients☆

    PubMed Central

    Marquis-Gravel, Guillaume; Hayami, Douglas; Juneau, Martin; Nigam, Anil; Guilbeault, Valérie; Latour, Élise; Gayda, Mathieu

    2015-01-01

    Objectives To analyze the effects of a long-term intensive lifestyle intervention including high-intensity interval training (HIIT) and Mediterranean diet (MedD) counseling on glycemic control parameters, insulin resistance and β-cell function in obese subjects. Methods The glycemic control parameters (fasting plasma glucose, glycated hemoglobin), insulin resistance, and β-cell function of 72 obese subjects (54 women; mean age = 53 ± 9 years) were assessed at baseline and upon completion of a 9-month intensive lifestyle intervention program conducted at the cardiovascular prevention and rehabilitation center of the Montreal Heart Institute, from 2009 to 2012. The program included 2–3 weekly supervised exercise training sessions (HIIT and resistance exercise), combined to MedD counseling. Results Fasting plasma glucose (FPG) (mmol/L) (before: 5.5 ± 0.9; after: 5.2 ± 0.6; P < 0.0001), fasting insulin (pmol/L) (before: 98 ± 57; after: 82 ± 43; P = 0.003), and insulin resistance, as assessed by the HOMA-IR score (before: 3.6 ± 2.5; after: 2.8 ± 1.6; P = 0.0008) significantly improved, but not HbA1c (%) (before: 5.72 ± 0.55; after: 5.69 ± 0.39; P = 0.448), nor β-cell function (HOMA-β, %) (before: 149 ± 78; after: 144 ± 75; P = 0.58). Conclusion Following a 9-month intensive lifestyle intervention combining HIIT and MedD counseling, obese subjects experienced significant improvements of FPG and insulin resistance. This is the first study to expose the effects of a long-term program combining HIIT and MedD on glycemic control parameters among obese subjects. PMID:26844086

  8. A new equation in two dimensional fast magnetoacoustic shock waves in electron-positron-ion plasmas

    SciTech Connect

    Masood, W.; Jehan, Nusrat; Mirza, Arshad M.

    2010-03-15

    Nonlinear properties of the two dimensional fast magnetoacoustic waves are studied in a three-component plasma comprising of electrons, positrons, and ions. In this regard, Kadomtsev-Petviashvili-Burger (KPB) equation is derived using the small amplitude perturbation expansion method. Under the condition that the electron and positron inertia are ignored, Burger-Kadomtsev-Petviashvili (Burger-KP) for a fast magnetoacoustic wave is derived for the first time, to the best of author's knowledge. The solutions of both KPB and Burger-KP equations are obtained using the tangent hyperbolic method. The effects of positron concentration, kinematic viscosity, and plasma beta are explored both for the KPB and the Burger-KP shock waves and the differences between the two are highlighted. The present investigation may have relevance in the study of nonlinear electromagnetic shock waves both in laboratory and astrophysical plasmas.

  9. Ultra-Fast Pump-Probe Detection Using Plasmas

    SciTech Connect

    Tatchyn, R.; /SLAC

    2006-02-17

    The temporal resolution of pump-flash interactions in the femtosecond-attosecond (fs-as) regime is limited by the characteristic time constants of the excited states in the detector material. If the relaxation time constant is appreciably longer that the time interval between the pump and probe signals the response of the detector material to the probe represents a temporal convolution with the pump and probe responses, setting a lower limit on the resolution to which the interval between the two pulses can be measured. In most of the solid state ultrafast detection schemes that are being considered for the ultrashort pulse x-ray sources under current development at SLAC and elsewhere the characteristic time constants are related to the bound states of the atoms comprising the material or to the relaxation times of phase transitions or charge carrier populations of the lattice, setting a probable lower limit on the attainable resolution on the order of {approx}0.1 ps. In this paper we consider a novel detection principle based on the excitation of specially prepared unbound states in an ionized plasma with high pump and probe fields, and estimate its potential for extending the lower limit of resolution into the attosecond (as) regime.

  10. Study of dynamical behaviour of the plasma in a dc non-transferred plasma torch using fast imaging

    NASA Astrophysics Data System (ADS)

    Goyal, Vidhi; Ravi, G.; Bandyopadhyay, P.; Banerjee, S.; Yugesh, V.; Mukherjee, S.

    2017-03-01

    The dynamical behaviour of the plasma in a dc non-transferred plasma torch is the result of complex interactions between various forces acting on the plasma column. We have studied this behaviour in a novel experiment comprising a low power (˜25 kW) torch and fast imaging diagnostics. The nitrogen gas plasma torch was operated at atmospheric pressure for a wide range of gas flow rates (20-60 lpm) and currents (70-120 A). A strong axial external magnetic field (100-500 G) was introduced and end-on images of the plasma column were captured using a high speed camera of frame rate ˜117 000 fps. The studies have yielded dominant role of external magnetic on the arc root dynamics. The column is clearly distinguishable in three main parts: central plasma, cathode-anode junction, and radial component of column that attaches to the anode. The dynamics of the column, especially the angular rotational speed of the radial part of the column, is analyzed in detail in terms of the forces that act upon it. The nature of the arc root attachment is observed to vary with variation in main experimental parameters, such as current, magnetic field, and flow. Arguments are invoked to explain the observed phenomena and a model of the physical processes is presented to explain the phenomena.

  11. Plasma obestatin is lower at fasting and not suppressed by insulin in insulin-resistant humans.

    PubMed

    Anderwald-Stadler, Marietta; Krebs, Michael; Promintzer, Miriam; Mandl, Martina; Bischof, Martin G; Nowotny, Peter; Kästenbauer, Thomas; Luger, Anton; Prager, Rudolf; Anderwald, Christian

    2007-11-01

    Obestatin, a recently discovered 23-amino acid peptide, is involved in the regulation of appetite and body weight in antagonistic fashion to ghrelin, both deriving from a common precursor peptide. Ghrelin was shown to be associated with insulin resistance, which may also affect obestatin. We investigated the association between insulin resistance and plasma concentrations of obestatin and ghrelin in nondiabetic individuals with high (IS; n = 18, 13 females and 5 males, age 47 +/- 2 yr, BMI = 25.5 +/- 0.9 kg/m(2)) and low (IR; n = 18, 12 females and 6 males, age 45 +/- 2 yr, P = 0.49, BMI = 27.5 +/- 1.1 kg/m(2), P = 0.17) insulin-stimulated glucose disposal (M), measured by 2-h hyperinsulinemic (40 mU.min(-1).m(-2)) isoglycemic clamp tests. M(100-120 min) was higher in IS (10.7 +/- 0.7) than in IR (4.4 +/- 0.2 mg.min(-1).kg(-1), P < 10(-9)), whereas insulin-dependent suppression of free fatty acids (FFA) in plasma was reduced in IR (71 +/- 6% vs. IS: 82 +/- 5%, P < 0.02). In both groups, plasma ghrelin concentrations were comparable at fasting and similarly reduced by 24-28% during insulin infusion. IR had lower fasting plasma obestatin levels (383 +/- 26 pg/ml vs. IS: 469 +/- 23 pg/ml, P < 0.02). Clamp insulin infusion reduced plasma obestatin to approximately 81% of basal values in IS (P < 0.00002), but not in IR. Fasting plasma obestatin was correlated positively with M (r = 0.34, P = 0.04), HDL cholesterol (r = 0.45, P = 0.01), and plasma ghrelin concentrations (r = 0.80, P < 0.000001) and negatively with measures of adiposity, plasma FFA during clamp (r = -0.42, P < 0.01), and systolic blood pressure (r = -0.33, P < 0.05). In conclusion, fasting plasma concentrations of obestatin, but not of ghrelin, are reduced in insulin resistance and are positively associated with whole body insulin sensitivity in nondiabetic humans. Furthermore, plasma obestatin is reduced by insulin in insulin-sensitive but not in insulin-resistant persons.

  12. Charge exchange fast neutral measurement with natural diamond detectors in neon plasma on LHD

    NASA Astrophysics Data System (ADS)

    Saida, T.; Sasao, M.; Isobe, M.; Krasilnikov, A. V.

    2003-03-01

    Charge exchange (CX) fast neutral spectra produced by ion cyclotron resonance frequency hydrogen minority heating in neon and helium majority plasmas sustained by neutral beam injection were measured with perpendicular Natural Diamond Detectors during the fifth campaign in 2002 on large helical devices (LHDs). It was observed that there were differences between fast neutral spectra shapes in neon plasma and those in helium of the same discharge condition with similar plasma parameters. Dominant CX processes in neon and helium plasmas were studied for ionization components from outside of the last closed flux surface. High-energy proton spectra were obtained by taking account of each charge state distribution and responsible charge exchange cross sections. The high-energy proton tail formations in both plasmas were similar for the same heating regime. The relaxation time tendencies of the effective temperatures of a high-energy proton have also shown no differences, indicating that the acceleration and confinement of energetic ions in LHDs are similar in neon and helium plasmas.

  13. Fast and Slow Mode Solitary Waves in a Five Component Plasma

    NASA Astrophysics Data System (ADS)

    Sebastian, Sijo; Michael, Manesh; Varghese, Anu; Sreekala, G.; Venugopal, Chandu

    2016-07-01

    We have investigated fast and slow mode solitary profiles in a five component plasma consisting of positively and negatively charged pair ions, hydrogen ions and hotter and colder electrons. Of these, the heavier ions and colder photo-electrons are of cometary origin while the other components are of solar origin; the electrons being described by kappa distributions. The Zakharov-Kuznetzov (ZK) equation is derived and solutions for fast and slow mode solitary structures are plotted for parameters relevant to that of comet Halley. From the figures, it is seen that the presence of hydrogen ion determines the polarity of fast and slow mode solitary structures. Also different pair ions like He, C and O have significant effect on the width of the fast and slow mode solitary structures.

  14. Role of Combined NNBI and ICRH Heating in FAST H-mode plasmas

    NASA Astrophysics Data System (ADS)

    Cardinali, A.; Calabrò, G.; Di Troia, C.; Marinucci, M.; Baiocchi, B.; Bilato, R.; Brambilla, M.; Briguglio, S.; Fogaccia, G.; Mantica, P.; Vlad, G.; Zonca, F.

    2011-12-01

    The combination of ICRH+NNBI in FAST allows the generation of fast ion populations with different velocity space anisotropy and radial profiles. These energetic ion populations can excite meso-scale fluctuations with the same characteristics of those expected in reactor conditions and, for this reason, FAST can address a number of important burning plasma physics issues. Numerical simulation and modeling of energetic particle physics are based on the use of transport codes that are iteratively coupled with a bi-dimensional full wave-quasi-linear solver for ICRH, in order to determinate the normalized supra-thermal population pressure ßhot. The value of ßhot. as well the energetic particle distribution functions can be used as initial condition for numerical simulation studies, investigating the destabilization and saturation of fast ion driven Alfvénic modes.

  15. Performance of a space-based wavelet compressor for plasma count data on the MMS Fast Plasma Investigation

    NASA Astrophysics Data System (ADS)

    Barrie, A. C.; Smith, S. E.; Dorelli, J. C.; Gershman, D. J.; Yeh, P.; Schiff, C.; Avanov, L. A.

    2017-01-01

    Data compression has been a staple of imaging instruments for years. Recently, plasma measurements have utilized compression with relatively low compression ratios. The Fast Plasma Investigation (FPI) on board the Magnetospheric Multiscale (MMS) mission generates data roughly 100 times faster than previous plasma instruments, requiring a higher compression ratio to fit within the telemetry allocation. This study investigates the performance of a space-based compression standard employing a Discrete Wavelet Transform and a Bit Plane Encoder (DWT/BPE) in compressing FPI plasma count data. Data from the first 6 months of FPI operation are analyzed to explore the error modes evident in the data and how to adapt to them. While approximately half of the Dual Electron Spectrometer (DES) maps had some level of loss, it was found that there is little effect on the plasma moments and that errors present in individual sky maps are typically minor. The majority of Dual Ion Spectrometer burst sky maps compressed in a lossless fashion, with no error introduced during compression. Because of induced compression error, the size limit for DES burst images has been increased for Phase 1B. Additionally, it was found that the floating point compression mode yielded better results when images have significant compression error, leading to floating point mode being used for the fast survey mode of operation for Phase 1B. Despite the suggested tweaks, it was found that wavelet-based compression, and a DWT/BPE algorithm in particular, is highly suitable to data compression for plasma measurement instruments and can be recommended for future missions.

  16. Comparative interactions between fast-flowing magnetized plasmas and comets, Mars, Venus and Titan

    NASA Astrophysics Data System (ADS)

    Mazelle, C.

    This review will summarize recent progress in the space plasma physics of solar system bodies (planets, planetary satellites and comets) interacting with a collisionless plasma wind such as the solar wind. One well-known class of objects are those possessing an intrinsic dynamo field such as the Earth, Mercury or giant planets. Their atmosphere is protected from the incident flow by the external boundary of their magnetosphere where the incident pressure is balanced by the intrinsic magnetic pressure allowing only impulsive penetration of solar wind plasma. For the second class of objects without measurable large scale magnetic field, the electrodynamical coupling occurs directly with the atmosphere and its upper part, the exosphere. This the case of Mars, and Venus and this makes these planets to also share common physical processes with comets. The interaction of Titan with the fast co-rotating plasma inside the magnetosphere of Saturn is another example of such interaction. Their plasma environment consists of characteristic boundaries separating regions with very different plasma conditions and dynamics (collisionless shock, magnetosheath, "induced" magnetosphere, ionosphere,...). Numerous open issues include atmospheric and ionospheric escapes, plasma boundaries and their dynamics, pickup ions, upstream waves, etc. Numerous open issues include atmospheric and ionospheric escapes, plasma boundaries and their dynamics, pickup ions, upstream waves, etc. Recent results in data analysis, e.g., from Mars Global Surveyor and Mars Express at Mars, from Cassini at Saturn and Titan or from Venus Express will be reported and compared with theoretical results, including numerical simulations.

  17. Development and Benchmarking of a Hybrid PIC Code For Dense Plasmas and Fast Ignition

    SciTech Connect

    Witherspoon, F. Douglas; Welch, Dale R.; Thompson, John R.; MacFarlane, Joeseph J.; Phillips, Michael W.; Bruner, Nicki; Mostrom, Chris; Thoma, Carsten; Clark, R. E.; Bogatu, Nick; Kim, Jin-Soo; Galkin, Sergei; Golovkin, Igor E.; Woodruff, P. R.; Wu, Linchun; Messer, Sarah J.

    2014-05-20

    Radiation processes play an important role in the study of both fast ignition and other inertial confinement schemes, such as plasma jet driven magneto-inertial fusion, both in their effect on energy balance, and in generating diagnostic signals. In the latter case, warm and hot dense matter may be produced by the convergence of a plasma shell formed by the merging of an assembly of high Mach number plasma jets. This innovative approach has the potential advantage of creating matter of high energy densities in voluminous amount compared with high power lasers or particle beams. An important application of this technology is as a plasma liner for the flux compression of magnetized plasma to create ultra-high magnetic fields and burning plasmas. HyperV Technologies Corp. has been developing plasma jet accelerator technology in both coaxial and linear railgun geometries to produce plasma jets of sufficient mass, density, and velocity to create such imploding plasma liners. An enabling tool for the development of this technology is the ability to model the plasma dynamics, not only in the accelerators themselves, but also in the resulting magnetized target plasma and within the merging/interacting plasma jets during transport to the target. Welch pioneered numerical modeling of such plasmas (including for fast ignition) using the LSP simulation code. Lsp is an electromagnetic, parallelized, plasma simulation code under development since 1995. It has a number of innovative features making it uniquely suitable for modeling high energy density plasmas including a hybrid fluid model for electrons that allows electrons in dense plasmas to be modeled with a kinetic or fluid treatment as appropriate. In addition to in-house use at Voss Scientific, several groups carrying out research in Fast Ignition (LLNL, SNL, UCSD, AWE (UK), and Imperial College (UK)) also use LSP. A collaborative team consisting of HyperV Technologies Corp., Voss Scientific LLC, FAR-TECH, Inc., Prism

  18. Fast camera studies at an electron cyclotron resonance table plasma generator

    SciTech Connect

    Rácz, R.; Biri, S.

    2014-02-15

    A simple table-size ECR plasma generator operates in the ATOMKI without axial magnetic trap and without any particle extraction tool. Radial plasma confinement is ensured by a NdFeB hexapole. The table-top ECR is a simplified version of the 14 GHz ATOMKI-ECRIS. Plasma diagnostics experiments are planned to be performed at this device before installing the measurement setting at the “big” ECRIS. Recently, the plasma generator has been operated in pulsed RF mode in order to investigate the time evolution of the ECR plasma in two different ways. (1) The visible light radiation emitted by the plasma was investigated by the frames of a fast camera images with 1 ms temporal resolution. Since the visible light photographs are in strong correlation with the two-dimensional spatial distribution of the cold electron components of the plasma it can be important to understand better the transient processes just after the breakdown and just after the glow. (2) The time-resolved ion current on a specially shaped electrode was measured simultaneously in order to compare it with the visible light photographs. The response of the plasma was detected by changing some external setting parameters (gas pressure and microwave power) and was described in this paper.

  19. Beams of fast neutral atoms and molecules in low-pressure gas-discharge plasma

    SciTech Connect

    Metel, A. S.

    2012-03-15

    Fast neutral atom and molecule beams have been studied, the beams being produced in a vacuum chamber at nitrogen, argon, or helium pressure of 0.1-10 Pa due to charge-exchange collisions of ions accelerated in the sheath between the glow discharge plasma and a negative grid immersed therein. From a flat grid, two broad beams of molecules with continuous distribution of their energy from zero up to e(U + U{sub c}) (where U is voltage between the grid and the vacuum chamber and U{sub c} is cathode fall of the discharge) are propagating in opposite directions. The beam propagating from the concave surface of a 0.2-m-diameter grid is focused within a 10-mm-diameter spot on the target surface. When a 0.2-m-diameter 0.2-m-high cylindrical grid covered by end disks and composed of parallel 1.5-mm-diameter knitting needles spaced by 4.5 mm is immersed in the plasma, the accelerated ions pass through the gaps between the needles, turn inside the grid into fast atoms or molecules, and escape from the grid through the gaps on its opposite side. The Doppler shift of spectral lines allows for measuring the fast atom energy, which corresponds to the potential difference between the plasma inside the chamber and the plasma produced as a result of charge-exchange collisions inside the cylindrical grid.

  20. Independent association of HbA(1c) and incident cardiovascular disease in people without diabetes.

    PubMed

    Adams, Robert J; Appleton, Sarah L; Hill, Catherine L; Wilson, David H; Taylor, Anne W; Chittleborough, Catherine R; Gill, Tiffany K; Ruffin, Richard E

    2009-03-01

    Recent studies have reported no association between elevated glycated hemoglobin (HbA(1c)) and incident cardiovascular disease (CVD) among women without diabetes. This study describes associations between HbA(1c) and new onset CVD in a representative adult population cohort. Assessment of participants in The North West Adelaide Health Study (NWAHS), a population study of randomly selected adults (age > or =18 years, n = 4,060), included measurement of height, weight, blood pressure, fasting lipids, glucose, and HbA(1c). A self-completed questionnaire assessed doctor-diagnosed diabetes, CVD and stroke, smoking status, and demographics. The cohort was followed for an average 3.5 years. Of the 2,913 adults free of diabetes at baseline and follow-up, 94 (3.5%) reported new onset coronary heart disease (CHD) and/or stroke. Compared with those with an HbA(1c) < or =5.0%, risk of new onset CVD was increased in those with HbA(1c) 5.4-5.6% (odds ratio (OR) 2.5, 95% confidence interval (CI) 1.4, 4.6), and > or =5.7% (OR 1.9, 95% CI 1.1, 3.4), after adjustment for other risk factors. The association was stronger in women than men (P = 0.03), and attenuated to only a small degree by addition of impaired fasting glucose (IFG), hypertension, hypercholesterolemia, BMI, waist circumference, or smoking to the model. Elevated HbA(1c) is related to new onset CVD over a relatively short follow-up period in both men and women without diabetes and who do not develop diabetes, after adjustment for other major risk factors. Unlike previous studies, this relationship was not substantially attenuated by other traditional risk factors.

  1. FAST TRACK COMMUNICATION: Plasma agents in bio-decontamination by dc discharges in atmospheric air

    NASA Astrophysics Data System (ADS)

    Machala, Zdenko; Chládeková, Lenka; Pelach, Michal

    2010-06-01

    Bio-decontamination of water and surfaces contaminated by bacteria (Salmonella typhimurium) was investigated in two types of positive dc discharges in atmospheric pressure air, in needle-to-plane geometry: the streamer corona and its transition to a novel regime called transient spark with short high current pulses of limited energy. Both generate a cold non-equilibrium plasma. Electro-spraying of treated water through a needle electrode was applied for the first time and resulted in fast bio-decontamination. Experiments providing separation of various biocidal plasma agents, along with the emission spectra and coupled with oxidation stress measurements in the cell membranes helped to better understand the mechanisms of microbial inactivation. The indirect exposure of contaminated surfaces to neutral active species was almost as efficient as the direct exposure to the plasma, whereas applying only UV radiation from the plasma had no biocidal effects. Radicals and reactive oxygen species were identified as dominant biocidal agents.

  2. Advances in High Harmonic Fast Wave Heating of NSTX H-mode Plasmas

    SciTech Connect

    Ryan, Philip Michael; Ahn, Joonwook; Bell, R. E.; Bonoli, P.; Chen, Guangye; Green, David L; Harvey, R. W.; Hosea, J.; Jaeger, Erwin Frederick; Kaye, S.; LeBlanc, B; Maingi, Rajesh; Phillips, Cynthia; Podesta, M.; Taylor, G.; Wilgen, John B; Wilson, J. R.

    2010-01-01

    High-harmonic fast wave (HHFW) heating and current drive is being developed in NSTX to provide bulk electron heating and q(0) control during non-inductively sustained Hmode plasmas fuelled by deuterium neutral-beam injection (NBI). In addition, it is used to assist the plasma current ramp-up. A major modification to increase the RF power limit was made in 2009; the original end-grounded, single end-powered current straps of the 12- element array were replaced with center-grounded, double end-powered straps. Greater than 3 MW have been coupled into NBI-driven, ELMy H-mode plasmas with this upgraded antenna. Improved core HHFW heating, particularly at longer wavelengths and during low-density start-up and plasma current ramp-up, has been obtained by lowering the edge density with lithium wall conditioning, thereby moving the critical density for fast-wave propagation away from the vessel wall [1]. Significant core electron heating of NBI-fuelled H-modes has been observed for the first time over a range of launched wavelengths and H-modes can be accessed by HHFW alone. Visible and IR camera images of the antenna and divertor indicate that fast wave interactions can deposit considerable RF energy on the outboard divertor plate, especially at longer wavelengths that begin to propagate closer to the vessel walls. Edge power loss can also arise from HHFWgenerated parametric decay instabilities; edge ion heating is observed that is wavelength dependent. During plasmas where HHFW is combined with NBI, there is a significant enhancement in neutron rate, and fast-ion D-alpha (FIDA) emission measurements clearly show broadening of the fast-ion profile in the plasma core. Large edge localized modes (ELMs) have been observed immediately following the termination of RF power, whether the power turn off is programmed or due to antenna arcing. Causality has not been established but new experiments are planned and will be reported. Fast digitization of the reflected power signal

  3. Leptin concentrations in plasma and follicular fluid from prepubertal gilts as influenced by fasting, refeeding and insulin.

    PubMed

    Govoni, N; Galeati, G; Castellani, G; Tamanini, C

    2005-03-01

    This study's aim was to examine whether fasting and refeeding would influence leptin levels in both plasma and follicular fluid from prepubertal gilts, and whether insulin affects leptin levels in fasting gilts. In experiment 1, four gilts were fasted for 72 h and then refed. Blood samples were withdrawn during normoalimentation, at the end of fasting, and for 4 h after refeeding. All samples were assayed for leptin; alternate samples were assayed for insulin, glucose and non-esterified fatty acids (NEFA). Fasting caused a decrease in leptin, glucose and insulin levels in plasma, while NEFA concentrations increased. In experiment 2, four gilts were given insulin as a bolus (0.2 IU/kg body weight) after 68 h of fasting. Blood samples were collected every 15 min around insulin administration and were assayed for leptin, insulin and glucose. This experiment shows that insulin administration increases leptin levels during fasting. In experiment 3, gilts were ovariectomized during normal alimentation (n=4), after 48 h of fasting (n=4), and after 48 h of realimentation following 48 h of fasting (n=4). Leptin levels in both plasma and follicular fluid collected after 48 h of fasting were significantly lower than those observed during normoalimentation or refeeding. In conclusion, a transient increase in insulin during fasting is effective in restoring leptin concentrations; in addition, leptin levels in follicular fluid parallel those in plasma.

  4. The influence of feeding and fasting on plasma metabolites in the dogfish shark (Squalus acanthias).

    PubMed

    Wood, Chris M; Walsh, Patrick J; Kajimura, Makiko; McClelland, Grant B; Chew, Shit F

    2010-04-01

    Dogfish sharks are opportunistic predators, eating large meals at irregular intervals. Here we present a synthesis of data from several previous studies on responses in plasma metabolites after natural feeding and during prolonged fasting (up to 56days), together with new data on changes in plasma concentrations of amino acids and non-esterified fatty acids. Post-prandial and long-term fasting responses were compared to control sharks fasted for 7days, a typical inter-meal interval. A feeding frenzy was created in which dogfish were allowed to feed naturally on dead teleosts at two consumed ration levels, 2.6% and 5.5% of body weight. Most responses were more pronounced at the higher ration level. These included increases in urea and TMAO concentrations at 20h, followed by stability through to 56days of fasting. Ammonia levels were low and exhibited little short-term response to feeding, but declined to very low values during the extended fast. Glucose and beta-hydroxybutyrate both fell after feeding, the latter to a greater and more prolonged extent (up to 60h), whereas acetoacetate did not change. During prolonged fasting, glucose concentrations were well regulated, but beta-hydroxybutyrate increased to 2-3-fold control levels. Total plasma amino acid concentrations increased in a biphasic fashion, with peaks at 6-20h, and 48-60h after the meal, followed by homeostasis during the extended fast. Essential and non-essential amino acids generally followed this same pattern, though some exhibited different trends after feeding: taurine, beta-alanine, and glycine (decreases or stability), alanine and glutamine (modest prolonged increases), and threonine, serine, asparagine, and valine (much larger short-term increases). Plasma non-esterified fatty acid concentrations declined markedly through 48h after the 2.6% meal. These data are interpreted in light of companion studies showing elevations in aerobic metabolic rate, urea production, rectal gland function, metabolic

  5. Challenges in HbA1c Analysis and Reporting in Patients with Variant Hemoglobins.

    PubMed

    Sultana, T A; Sheme, Z A; Sultana, G S; Sultana, B; Mishu, F A; Khan, N Z; Sarkar, B C; Muttalib, M A; Khan, S A; Choudhury, S; Mahtab, H

    2016-04-01

    Hemoglobin A1c (HbA(1)c) is a well-established indicator of mean glycemia. The presence of genetic variants of hemoglobin can profoundly affect the accuracy of HbA(1)c measurements. Variants of hemoglobin especially Hemoglobin E (HbE) is prevalent in South East Asia including Bangladesh. The objective of our study is to compare the HbA(1)c values measured on high performance liquid chromatography (HPLC) and Turbidimetric Inhibition Immunoassay (TINIA) in diabetic patients with variant hemoglobins including HbE. A total of 7595 diabetic patients receiving treatment at BIRDEM General Hospital were analyzed for HbA(1)c results within a period of two months from December 2013 to January 2014. Seventy two cases out of 7595 (0.95%) had either undetectable or below normal HbA(1)c levels (males-33 and females-39; ratio = 0.82:1) by HPLC method. In 34(0.45%) cases, HbA(1)c value was undetectable by HPLC method but was in the reportable range by TINIA method. In the other 38 (0.55%) cases, HbA(1)c levels were below the reportable range (<4%) by HPLC method but were in the normal or higher range by TINIA method. TINIA method did not agree with HPLC method on Bland Altman plot in the 38 cases with below normal HbA(1)c levels, [Mean bias -5.2(-9.3 to 1.0), 95% CI] but agreed very well [mean bias -0.21 (-0.84 to 0.42), y=1.1037+0.776X; r(2)=0.30, p<0.01] in controls. In control group mean MCV was 83.80±7.48 and in study group was 73.65±10.44. Alkaline electrophoresis confirmed the variant hemoglobin to be HbE. The fasting blood sugar levels of all the 72 cases correlated strongly with TINIA method (r(2) =0.75, p<0.0001) but not with HPLC (r = 0.24, p=0.13). In our regions where populations have a high prevalence of Hb variant, proper knowledge of hemoglobin variants which affect the measurements HbA(1)c level is essential. MCV of 80fl or below may serve as a rough guide to select samples that require analysis by TINIA method. Moreover, HPLC may be a convenient and inexpensive

  6. Solitary fast magnetosonic waves propagating obliquely to the magnetic field in cold collisionless plasma

    SciTech Connect

    Kichigin, G. N.

    2016-01-15

    Solutions describing solitary fast magnetosonic (FMS) waves (FMS solitons) in cold magnetized plasma are obtained by numerically solving two-fluid hydrodynamic equations. The parameter domain within which steady-state solitary waves can propagate is determined. It is established that the Mach number for rarefaction FMS solitons is always less than unity. The restriction on the propagation velocity leads to the limitation on the amplitudes of the magnetic field components of rarefaction solitons. It is shown that, as the soliton propagates in plasma, the transverse component of its magnetic field rotates and makes a complete turn around the axis along which the soliton propagates.

  7. Monochromatic x-ray sampling streak imager for fast-ignitor plasma observation

    SciTech Connect

    Tanabe, Minoru; Fujiwara, Takashi; Fujioka, Shinsuke; Nishimura, Hiroaki; Shiraga, Hiroyuki; Azechi, Hiroshi; Mima, Kunioki

    2008-10-15

    Ultrafast two-dimensional (2D) x-ray imaging is required to investigate the dynamics of fast-heated core plasma in inertial confinement fusion research. A novel x-ray imager, consisting of two toroidally bent Bragg crystals and an ultrafast 2D x-ray imaging camera, has been demonstrated. Sequential and 2D monochromatic x-ray images of laser-imploded core plasma were obtained with a temporal resolution of 20 ps, a spatial resolution of 31 {mu}m, and a spectral resolution of over 200, simultaneously.

  8. Development of fast steering mirror control system for plasma heating and diagnostics

    SciTech Connect

    Okada, K. Kubo, S.; Shimozuma, T.; Yoshimura, Y.; Igami, H.; Takahashi, H.; Tanaka, K.; Kobayashi, S.; Ito, S.; Mizuno, Y.; Ogasawara, S.; Nishiura, M.

    2014-11-15

    A control system for a fast steering mirror has been newly developed for the electron cyclotron heating (ECH) launchers in the large helical device. This system enables two-dimensional scan during a plasma discharge and provides a simple feedback control function. A board mounted with a field programmable gate array chip has been designed to realize feedback control of the ECH beam position to maintain higher electron temperature by ECH. The heating position is determined by a plasma diagnostic signal related to the electron temperature such as electron cyclotron emission and Thomson scattering.

  9. Fast magnetic field annihilation driven by two laser pulses in underdense plasma

    SciTech Connect

    Gu, Y. J.; Kumar, D.; Weber, S.; Korn, G.; Klimo, O.; Bulanov, S. V.; Esirkepov, T. Zh.

    2015-10-15

    Fast magnetic annihilation is investigated by using 2.5-dimensional particle-in-cell simulations of two parallel ultra-short petawatt laser pulses co-propagating in underdense plasma. The magnetic field generated by the laser pulses annihilates in a current sheet formed between the pulses. Magnetic field energy is converted to an inductive longitudinal electric field, which efficiently accelerates the electrons of the current sheet. This new regime of collisionless relativistic magnetic field annihilation with a timescale of tens of femtoseconds can be extended to near-critical and overdense plasma with the ultra-high intensity femtosecond laser pulses.

  10. Fast Formation of Magnetic Islands in a Plasma in the Presence of Counterstreaming Electrons

    SciTech Connect

    Califano, F.; Attico, N.; Pegoraro, F.; Bertin, G.; Bulanov, S. V.

    2001-06-04

    With the help of 2D-3V (two dimensional in space and three dimensional in velocity) Vlasov simulations we show that the magnetic field generated by the electromagnetic current filamentation instability develops magnetic islands due to the onset of a fast reconnection process that occurs on the electron dynamical time scale. This process is relevant to magnetic channel coalescence in relativistic laser plasma interactions.

  11. Existence domains of slow and fast ion-acoustic solitons in two-ion space plasmas

    SciTech Connect

    Maharaj, S. K.; Bharuthram, R.; Singh, S. V. Lakhina, G. S.

    2015-03-15

    A study of large amplitude ion-acoustic solitons is conducted for a model composed of cool and hot ions and cool and hot electrons. Using the Sagdeev pseudo-potential formalism, the scope of earlier studies is extended to consider why upper Mach number limitations arise for slow and fast ion-acoustic solitons. Treating all plasma constituents as adiabatic fluids, slow ion-acoustic solitons are limited in the order of increasing cool ion concentrations by the number densities of the cool, and then the hot ions becoming complex valued, followed by positive and then negative potential double layer regions. Only positive potentials are found for fast ion-acoustic solitons which are limited only by the hot ion number density having to remain real valued. The effect of neglecting as opposed to including inertial effects of the hot electrons is found to induce only minor quantitative changes in the existence regions of slow and fast ion-acoustic solitons.

  12. Stability properties and fast ion confinement of hybrid tokamak plasma configurations

    NASA Astrophysics Data System (ADS)

    Graves, J. P.; Brunetti, D.; Pfefferle, D.; Faustin, J. M. P.; Cooper, W. A.; Kleiner, A.; Lanthaler, S.; Patten, H. W.; Raghunathan, M.

    2015-11-01

    In hybrid scenarios with flat q just above unity, extremely fast growing tearing modes are born from toroidal sidebands of the near resonant ideal internal kink mode. New scalings of the growth rate with the magnetic Reynolds number arise from two fluid effects and sheared toroidal flow. Non-linear saturated 1/1 dominant modes obtained from initial value stability calculation agree with the amplitude of the 1/1 component of a 3D VMEC equilibrium calculation. Viable and realistic equilibrium representation of such internal kink modes allow fast ion studies to be accurately established. Calculations of MAST neutral beam ion distributions using the VENUS-LEVIS code show very good agreement of observed impaired core fast ion confinement when long lived modes occur. The 3D ICRH code SCENIC also enables the establishment of minority RF distributions in hybrid plasmas susceptible to saturated near resonant internal kink modes.

  13. Association of Postbreakfast Triglyceride and Visit-to-Visit Annual Variation of Fasting Plasma Glucose with Progression of Diabetic Nephropathy in Patients with Type 2 Diabetes

    PubMed Central

    Kitaoka, Kaori; Takenouchi, Akiko; Tsuboi, Ayaka; Fukuo, Keisuke

    2016-01-01

    Urinary albumin/creatinine ratio (ACR) was measured at baseline and after a median follow-up of 6.0 years in 161 patients with type 2 diabetes. Intrapersonal means and SD of HbA1c, systolic BP, fasting, and postmeal plasma glucose (FPG and PMPG, resp.) and serum triglycerides (FTG and PMTG, resp.) were calculated in each patient during the first 12 months after enrollment. Associations of these variables with nephropathy progression (15 patients with progression of albuminuric stages and 5 with ACR doubling within the microalbuminuric range) were determined by multivariate logistic regression analysis providing odds ratio with 95% confidential interval. Patients with nephropathy progression, compared with those without nephropathy progression, had higher HbA1c (p < 0.01). They also had higher means and SD of FPG (both p < 0.05), FTG (both p < 0.05), and PMTG (p = 0.001). Multivariate logistic regression analysis demonstrated that SD-FPG (1.036, 1.001–1.073, p = 0.04) and PMTG (1.013, 1.008–1.040, p = 0.001) were significant predictors of progression of nephropathy even after adjustment for mean FPG and SD-FTG, age, sex, BMI, waist circumference, diabetes duration and therapy, means and SDs of HbA1c, PPG, FTG and systolic BP, baseline ACR, smoking status, and uses of antihypertensive and lipid-lowering medications. Consistency of glycemic control and management of postmeal TG may be important to prevent nephropathy progression in type 2 diabetic patients. PMID:27975066

  14. Numerical studies of fast ion slowing down rates in cool magnetized plasma using LSP

    NASA Astrophysics Data System (ADS)

    Evans, Eugene S.; Kolmes, Elijah; Cohen, Samuel A.; Rognlien, Tom; Cohen, Bruce; Meier, Eric; Welch, Dale R.

    2016-10-01

    In MFE devices, rapid transport of fusion products from the core into the scrape-off layer (SOL) could perform the dual roles of energy and ash removal. The first-orbit trajectories of most fusion products from small field-reversed configuration (FRC) devices will traverse the SOL, allowing those particles to deposit their energy in the SOL and be exhausted along the open field lines. Thus, the fast ion slowing-down time should affect the energy balance of an FRC reactor and its neutron emissions. However, the dynamics of fast ion energy loss processes under the conditions expected in the FRC SOL (with ρe <λDe) are analytically complex, and not yet fully understood. We use LSP, a 3D electromagnetic PIC code, to examine the effects of SOL density and background B-field on the slowing-down time of fast ions in a cool plasma. As we use explicit algorithms, these simulations must spatially resolve both ρe and λDe, as well as temporally resolve both Ωe and ωpe, increasing computation time. Scaling studies of the fast ion charge (Z) and background plasma density are in good agreement with unmagnetized slowing down theory. Notably, Z-scaling represents a viable way to dramatically reduce the required CPU time for each simulation. This work was supported, in part, by DOE Contract Number DE-AC02-09CH11466.

  15. Hollow Cathode and Keeper-region Plasma Measurements Using Ultra-fast Miniature Scanning Probes

    NASA Technical Reports Server (NTRS)

    Goebel, Dan M.; Jameson, Kristina K.; Watkins, Ron M.; Katz, Ira

    2004-01-01

    In order to support the development of comprehensive performance and life models for future deep space missions that will utilize ion thrusters, we have undertaken a study of the plasma structure in hollow cathodes using an new pneumatic scanning probe diagnostic. This device is designed to insert a miniature probe directly into the hollow cathode orifice from either the upstream insert region in the interior of the hollow cathode, or from the downstream keeper-plasma region at the exit of the hollow cathode, to provide complete axial profiles of the discharge plasma parameters. Previous attempts to diagnose this region with probes was Limited by the melting of small probes in the intense discharge near the orifice, or caused significant perturbation of the plasma by probes large enough to survive. Our new probe is extremely compact, and when configured as a single Langmuir probe, the ceramic tube insulator is only 0.5mm in diameter and the current collecting conductor has a total area of 0.002 cm2. A series of current-voltage characteristics are obtained by applying a rapid sawtooth voltage waveform to the probe as it is scanned by the pneumatic actuator into and out of the plasma region, The bellow-sealed pneumatic drive scans the probe 4 cm in the cathode insert region and 10 cm in the anode/keeper plasmas region at average speeds of about 1 mm/msec, and the residence time at the end of the insertion stroke in the densest part of the plasma near the orifice is measured to be only 10 msec. Since the voltage sweep time is fast compared to the motion of the probe, axial profiles of the plasma density, temperature and potential with reasonable spatial resolution are obtained. Measurements of the internal cathode pressures and the axial plasma-parameter profiles for a hollow cathode operating at discharge currents of up to 35 A in xenon will be presented.

  16. Fast functionalization of multi-walled carbon nanotubes by an atmospheric pressure plasma jet.

    PubMed

    Kolacyak, Daniel; Ihde, Jörg; Merten, Christian; Hartwig, Andreas; Lommatzsch, Uwe

    2011-07-01

    The afterglow of an atmospheric pressure plasma has been used for the fast oxidative functionalization of multi-walled carbon nanotubes (MWCNTs). Scanning electron microscopy and Raman spectroscopy demonstrate that the MWCNT morphology is mostly preserved when the MWCNTs are dispersed in a solvent and injected as a spray into the plasma. Contact angle measurements show that this approach enhances the wettability of MWCNTs and reduces their sedimentation in an aqueous dispersion. X-ray photoelectron spectroscopy, IR spectroscopy, and electrokinetic measurements show that oxygen plasma incorporates about 6.6 at.% of oxygen and creates mainly hydroxyl and carboxyl functional groups on the MWCNT surface. The typical effective treatment time is estimated to be in the range of milliseconds. The approach is ideally suited for combination with the industrial gas phase CVD synthesis of MWCNTs.

  17. Interpretation of fast measurements of plasma potential, temperature and density in SOL of ASDEX Upgrade

    NASA Astrophysics Data System (ADS)

    Horacek, J.; Adamek, J.; Müller, H. W.; Seidl, J.; Nielsen, A. H.; Rohde, V.; Mehlmann, F.; Ionita, C.; Havlíčková, E.; ASDEX Upgrade Team

    2010-10-01

    This paper focuses on interpretation of fast (1 µs) and local (2-4 mm) measurements of plasma density, potential and electron temperature in the edge plasma of tokamak ASDEX Upgrade. Steady-state radial profiles demonstrate the credibility of the ball-pen probe. We demonstrate that floating potential fluctuations measured by a Langmuir probe are dominated by plasma electron temperature rather than potential. Spatial and temporal scales are found consistent with expectations based on interchange-driven turbulence. Conditionally averaged signals found for both potential and density are also consistent; however, those for temperature show an unexpected ~4 mm wide decrease by 10% at the very centre of a blob. In the wall shadow, temperature measured by the swept Langmuir probe yields values ~10 eV, whilst the ball-pen temperature gradient is more steep and credible, dropping down to ~1 eV.

  18. Fast gated imaging of the collisionless interaction of a laser-produced and magnetized ambient plasma

    NASA Astrophysics Data System (ADS)

    Heuer, P. V.; Schaeffer, D. B.; Knall, E. N.; Constantin, C. G.; Hofer, L. R.; Vincena, S.; Tripathi, S.; Niemann, C.

    2017-03-01

    The collisionless interaction between a laser-produced carbon plasma (LPP) and an ambient hydrogen plasma in a background magnetic field was studied in a high shot rate experiment which allowed large planar data sets to be collected. Plasma fluorescence was imaged with a fast-gated camera with and without carbon line filters. The resulting images were compared to high-resolution two dimensional (2D) data planes of measured magnetic field and electric potential. Several features in the fluorescence images coincide with features in the field data. Relative intensity was used to determine the initial angular velocity distribution of the LPP and the growth rate of instabilities. These observations may be applied to understand fluorescence images from similar experiments where 2D planes of field data are not available.

  19. Effects of Sleep Disorders on Hemoglobin A1c Levels in Type 2 Diabetic Patients

    PubMed Central

    Keskin, Ahmet; Ünalacak, Murat; Bilge, Uğur; Yildiz, Pinar; Güler, Seda; Selçuk, Engin Burak; Bilgin, Muzaffer

    2015-01-01

    Background: Studies have reported the presence of sleep disorders in approximately 50–70% of diabetic patients, and these may contribute to poor glycemic control, diabetic neuropathy, and overnight hypoglycemia. The aim of this study was to determine the frequency of sleep disorders in diabetic patients, and to investigate possible relationships between scores of these sleep disorders and obstructive sleep apnea syndrome (OSAS) and diabetic parameters (fasting blood glucose, glycated hemoglobin A1c [HbA1c], and lipid levels). Methods: We used the Berlin questionnaire (BQ) for OSAS, the Epworth Sleepiness Scale (ESS), and the Pittsburgh Sleep Quality Index (PSQI) to determine the frequency of sleep disorders and their possible relationships with fasting blood glucose, HbA1c, and lipid levels. Results: The study included 585 type 2 diabetic patients admitted to family medicine clinics between October and December 2014. Sleep, sleep quality, and sleep scores were used as the dependent variables in the analysis. The ESS scores showed that 54.40% of patients experienced excessive daytime sleepiness, and according to the PSQI, 64.30% experienced poor-quality sleep. The BQ results indicated that 50.20% of patients were at high-risk of OSAS. HbA1c levels correlated significantly with the ESS and PSQI results (r = 0.23, P < 0.001 and r = 0.14, P = 0.001, respectively), and were significantly higher in those with high-risk of OSAS as defined by the BQ (P < 0.001). These results showed that HbA1c levels were related to sleep disorders. Conclusions: Sleep disorders are common in diabetic patients and negatively affect the control of diabetes. Conversely, poor diabetes control is an important factor disturbing sleep quality. Addressing sleep disturbances in patients who have difficulty controlling their blood glucose has dual benefits: Preventing diabetic complications caused by sleep disturbance and improving diabetes control. PMID:26668142

  20. Elevations of C14:1 and C14:2 Plasma Acylcarnitines in Fasted Children: A Diagnostic Dilemma

    PubMed Central

    Burrage, Lindsay C.; Miller, Marcus J.; Wong, Lee-Jun; Kennedy, Adam D.; Sutton, V. Reid; Sun, Qin; Elsea, Sarah H.; Graham, Brett H.

    2015-01-01

    Objectives To test whether follow-up testing for VLCAD deficiency uncovers a diagnosis in patients with elevations of C14:1 and C14:2 plasma acylcarnitines after a controlled fasting study performed for clinically-suspected hypoglycemia and to compare the acylcarnitine profiles from fasted patients without VLCAD deficiency vs. patients with known VLCAD deficiency to determine if metabolite testing distinguishes these groups. Study design We performed a retrospective chart review and identified 17 patients with elevated C14:1 and C14:2 plasma acylcarnitine levels after a controlled fast and with testing for VLCAD deficiency (ACADVL sequencing or fibroblast fatty acid oxidation studies). The follow-up testing in all patients was inconsistent with a diagnosis of VLCAD deficiency. We compared the plasma acylcarnitine profiles from these fasted patients vs. patients with VLCAD deficiency. Results C14:1/C12:1 was significantly lower (p<0.001) in fasted patients vs. patients with VLCAD deficiency. Metabolomics analysis performed in two fasted patients and one patient with VLCAD deficiency demonstrated evidence for upregulated lipolysis and β-oxidation in the fasted state. Conclusions Elevations of plasma C14:1 and C14:2 acylcarnitines appear to be a physiologic result of lipolysis that occurs with fasting. Both metabolomics analysis and/or C14:1/C12:1 may distinguish C14:1 elevations from physiologic fasting-induced lipolysis vs. VLCAD deficiency. PMID:26602010

  1. Observation and suppression of a new fast ion driven micro burst instability in a field-reversed configuration plasma

    NASA Astrophysics Data System (ADS)

    Deng, B. H.; Korepanov, S.; Belova, E.; Douglass, J.; Beall, M.; Binderbauer, M.; Clary, R.; Detrick, S.; Garate, E.; Gota, H.; Granstedt, E.; Magee, R.; Necas, A.; Putvinski, S.; Roche, T.; Smirnov, A.; Tajima, T.; Thompson, M.; Tuszewski, M.; van Drie, A.; TAE Team

    2016-10-01

    The C-2U experiment offers a unique plasma environment combining a high beta field reversed configuration (FRC) embedded in a low beta magnetic mirror with high power neutral beam injection. The beams are injected tangentially into a modest magnetic field so that the orbits of the resulting fast ions encircle the entire plasma. The dominant population of large orbit fast ions sustains and stabilizes the FRC, suppresses turbulence, and makes a dramatic beneficial impact on the overall plasma performance. Abundant interesting new physics phenomena are observed in this high performance FRC operation regime, including micro bursts, which are benign, periodic bursting small amplitude down chirping fluctuations seen by several diagnostics. Detailed analysis of the micro bursts measurement data, bulk plasma equilibrium profiles, and fast ion orbit characteristics show that the micro bursts might be driven by a small number of resonant fast ions, and can be suppressed when the number of resonant particles is reduced.

  2. Electron Generation and Transport in Intense Relativistic Laser-Plasma Interactions Relevant to Fast Ignition ICF

    SciTech Connect

    Ma, Tammy Yee Wing

    2010-01-01

    The reentrant cone approach to Fast Ignition, an advanced Inertial Confinement Fusion scheme, remains one of the most attractive because of the potential to efficiently collect and guide the laser light into the cone tip and direct energetic electrons into the high density core of the fuel. However, in the presence of a preformed plasma, the laser energy is largely absorbed before it can reach the cone tip. Full scale fast ignition laser systems are envisioned to have prepulses ranging between 100 mJ to 1 J. A few of the imperative issues facing fast ignition, then, are the conversion efficiency with which the laser light is converted to hot electrons, the subsequent transport characteristics of those electrons, and requirements for maximum allowable prepulse this may put on the laser system. This dissertation examines the laser-to-fast electron conversion efficiency scaling with prepulse for cone-guided fast ignition. Work in developing an extreme ultraviolet imager diagnostic for the temperature measurements of electron-heated targets, as well as the validation of the use of a thin wire for simultaneous determination of electron number density and electron temperature will be discussed.

  3. Fast and Slow Mode Solitary Waves in a Five-Component Plasma

    NASA Astrophysics Data System (ADS)

    Sebastian, Sijo; Michael, Manesh; Sreekala, G.; Varghese, Anu; Venugopal, Chandu

    2017-02-01

    We have investigated fast- and slow-mode solitary profiles in a five-component plasma consisting of positively and negatively charged pair ions, hydrogen ions, and hotter and colder electrons. Of these, the heavier ions and colder photoelectrons are of cometary origin while the other components are of solar origin; the electrons are described by kappa distributions. The Zakharov-Kuznetsov (ZK) equation is derived, and solutions for fast- and slow-mode solitary structures are plotted for parameters relevant to comet Halley. We found that the presence of hydrogen ions determines the polarity of the fast- and slow-mode solitary structures. Also, variations of equilibrium number density of hydrogen ions and charge numbers on the heavier pair ions act differently on the fast- and slow-mode solitary structures. The addition of hydrogen ions significantly affects the amplitude of the solitary structures for the fast mode. Further, the cyclotron frequency of the lighter and heavier ions has a noticeable effect on the width of the solitary waves.

  4. Effects of fasting on plasma glucose and prolonged tracer measurement of hepatic glucose output in NIDDM

    SciTech Connect

    Glauber, H.; Wallace, P.; Brechtel, G.

    1987-10-01

    We studied the measurement of hepatic glucose output (HGO) with prolonged (3-/sup 3/H)glucose infusion in 14 patients with non-insulin-dependent diabetes mellitus (NIDDM). Over the course of 10.5 h, plasma glucose concentration fell with fasting by one-third, from 234 +/- 21 to 152 +/- 12 mg/dl, and HGO fell from 2.35 +/- 0.18 to 1.36 +/- 0.07 mg . kg-1 . min-1 (P less than .001). In the basal state, HGO and glucose were significantly correlated (r = 0.68, P = .03), and in individual patients, HGO and glucose were closely correlated as both fell with fasting (mean r = 0.79, P less than .01). Plasma (3-/sup 3/H)glucose radioactivity approached a steady state only 5-6 h after initiation of the primed continuous infusion, and a 20% overestimate of HGO was demonstrated by not allowing sufficient time for tracer labeling of the glucose pool. Assumption of steady-state instead of non-steady-state kinetics in using Steele's equations to calculate glucose turnover resulted in a 9-24% overestimate of HGO. Stimulation of glycogenolysis by glucagon injection demonstrated no incorporation of (3-/sup 3/H)glucose in hepatic glycogen during the prolonged tracer infusion. In a separate study, plasma glucose was maintained at fasting levels (207 +/- 17 mg/dl) for 8 h with the glucose-clamp technique. Total glucose turnover rates remained constant during this prolonged tracer infusion. However, HGO fell to 30% of the basal value simply by maintaining fasting hyperglycemia in the presence of basal insulin levels.

  5. Fasting plasma total ghrelin concentrations in monozygotic twins discordant for obesity.

    PubMed

    Leskelä, Piia; Ukkola, Olavi; Vartiainen, Johanna; Rönnemaa, Tapani; Kaprio, Jaakko; Bouchard, Claude; Kesäniemi, Y Antero

    2009-02-01

    Ghrelin is a hormone that is involved in the regulation of food intake. Neuronal, endocrine, and genetic factors have been shown to regulate plasma ghrelin levels; but the determinants of fasting ghrelin concentrations are not yet fully understood. The main aim was to explore the roles of adiposity and genetic differences in determining fasting plasma total ghrelin levels. We measured total ghrelin levels in a population of 23 monozygotic twin pairs discordant for obesity. In addition, 2 variants of ghrelin gene, namely, Arg51Gln and Leu72Met, were genotyped in 3 populations of monozygotic twin pairs: 23 obesity-discordant, 43 lean-concordant, and 46 obesity-concordant twin pairs. In discordant twins, lean co-twins had higher fasting plasma total ghrelin levels (950 pg/mL, SD = 328 pg/mL) than obese twins (720 pg/mL, SD = 143 pg/mL; P = .003). Arg51Gln-polymorphism of the ghrelin gene was equally distributed between the twin groups. However, there were significant differences in genotype frequencies at the Leu72Met polymorphism between the discordant and obese-concordant groups (P = .003) and between the discordant and lean-concordant groups (P = .011), but not between the 2 concordant groups. In the discordant group, there were fewer Met carriers (4%) than among the obese (17%) or the lean-concordant groups (15%). Plasma total ghrelin levels are affected by acquired obesity independent of genetic background. The Leu72 allele is particularly common among monozygotic twins discordant for obesity, suggesting that this ghrelin allele is more permissive in the regulation of energy balance. The ghrelin gene may thus play a role in the regulation of variability of body weight, such that Leu72 allele carriers are more prone to weight variability in response to environmental factors.

  6. Fast Sausage Modes in Magnetic Tubes with Continuous Transverse Profiles: Effects of a Finite Plasma Beta

    NASA Astrophysics Data System (ADS)

    Chen, Shao-Xia; Li, Bo; Xiong, Ming; Yu, Hui; Guo, Ming-Zhe

    2016-12-01

    While standing fast sausage modes in flare loops are often invoked to interpret quasi-periodic pulsations (QPPs) in solar flares, it is unclear as to how they are influenced by the combined effects of a continuous transverse structuring and a finite internal plasma beta ({β }{{i}}). We derive a generic dispersion relation governing linear sausage waves in straight magnetic tubes for which plasma pressure is not negligible, and the density and temperature inhomogeneities of essentially arbitrary form take place in a layer of arbitrary width. Focusing on fast modes, we find that {β }{{i}} only weakly influences {k}{{c}}, the critical longitudinal wavenumber separating the leaky from trapped modes. Likewise, for both trapped and leaky modes, the periods P in units of the transverse fast time depend only weakly on {β }{{i}}, which is compatible with the fact that the effective wave vectors of fast sausage modes are largely perpendicular to the background magnetic field. However, a weak {β }{{i}} dependence of the damping times τ is seen only when the length-to-radius ratio L/R is ∼50% larger than some critical value π /({k}{{c}}R), which itself rather sensitively depends on the density contrast, profile steepness, as well as on how the transverse structuring is described. In the context of QPPs, we conclude that the much simpler zero-beta theory can be employed for trapped modes, as long as one sees the deduced internal Alfvén speed as actually being the fast speed. In contrast, effects due to a finite beta in flare loops should be considered when leaky modes are exploited.

  7. Magnetic field measurements for study of fast electron transport in magnetized HED plasma

    NASA Astrophysics Data System (ADS)

    Sawada, Hiroshi; Griffin, Brandon; Presura, Radu; Haque, Showera; Sentoku, Yasuhiko

    2014-10-01

    Interaction of megagauss magnetic fields with high energy density (HED) plasma is of great interest in the field of magnetized plasma. The field changes fundamental properties of the HED plasma such as thermal and magnetic diffusion. A coupled capability utilizing the 1.0 MA Zebra pulsed power generator and the 50 TW Leopard laser at Nevada Terawatt Facility enables to create such a condition for studies of magnetized plasma properties. We have conducted an experiment to measure magnetic fields generated by a 1.0 MA, 100 ns Zebra pulsed current in stainless steel coils. Using a 532 nm continuous laser from a single longitudinal mode laser system, the temporal change in the magnetic field was measured with the Faraday rotation in F2 glass. The probe laser passing through the 1.5 mm in radius and 1.75 mm thick glass placed in the vicinity of the inductive coils was split with a Glan-Taylor prism to measure vertical and horizontal polarization components with photodiodes. We will present the analysis of the experimental result and a design of a coupled experiment for study of fast electron transport in the magnetized plasma.

  8. Spectroscopic investigation of fast (ns) magnetic field penetration in a plasma

    NASA Astrophysics Data System (ADS)

    Sarfaty, M.; Shpitalnik, R.; Arad, R.; Weingarten, A.; Krasik, Ya. E.; Fruchtman, A.; Maron, Y.

    1995-06-01

    The time-dependent magnetic field spatial distribution in a coaxial positive-polarity plasma opening switch (POS) carrying a current ≂135 kA during ≂100 ns, was investigated by two methods. In the first, ionic line emission was observed simultaneously for two polarizations to yield the Doppler and Zeeman contributions to the line profiles. In the second method, the axial velocity distribution of ions was determined, giving the magnetic field through the ion equation of motion. This method requires knowledge of the electron density, here obtained from the observed particle ionization times. To this end, a lower bound for the electron kinetic energy was determined using various line intensities and time-dependent collisional-radiative calculations. An important necessity for POS studies is the locality of all measurements in r, z, and θ. This was achieved by using laser evaporation to seed the plasma nonperturbingly with the species desired for the various measurements. The Zeeman splitting and the ion motion showed magnetic field penetration through the 3.5 cm long plasma at a velocity ≂108 cm/s. The current density was found to be relatively high at the load-side edge of the switch plasma. It is suggested that this may cause plasma acceleration into the vacuum section toward the load, which is supported by charge-collector measurements. The fast magnetic field penetration agrees with estimates based on the Hall-field mechanism.

  9. Nonlinear interaction of fast particles with Alfven waves in toroidal plasmas

    SciTech Connect

    Candy, J.; Borba, D.; Huysmans, G.T.A.; Kerner, W.; Berk, H.L.

    1996-12-17

    A numerical algorithm to study the nonlinear, resonant interaction of fast particles with Alfven waves in tokamak geometry has been developed. The scope of the formalism is wide enough to describe the nonlinear evolution of fishbone modes, toroidicity-induced Alfven eigenmodes and ellipticity-induced Alfven eigenmodes, driven by both passing and trapped fast ions. When the instability is sufficiently weak, it is known that the wave-particle trapping nonlinearity will lead to mode saturation before wave-wave nonlinearities are appreciable. The spectrum of linear modes can thus be calculated using a magnetohydrodynamic normal-mode code, then nonlinearly evolved in time in an efficient way according to a two-time-scale Lagrangian dynamical wave model. The fast particle kinetic equation, including the effect of orbit nonlinearity arising from the mode perturbation, is simultaneously solved of the deviation, {delta}f = f {minus} f{sub 0}, from an initial analytic distribution f{sub 0}. High statistical resolution allows linear growth rates, frequency shifts, resonance broadening effects, and nonlinear saturation to be calculated quickly and precisely. The results have been applied to an ITER instability scenario. Results show that weakly-damped core-localized modes alone cause negligible alpha transport in ITER-like plasmas--even with growth rates one order of magnitude higher than expected values. However, the possibility of significant transport in reactor-type plasmas due to weakly unstable global modes remains an open question.

  10. Neutron Production and Fast Deuteron Characteristics at the Plasma Focus Discharge

    SciTech Connect

    Kubes, P.; Kravarik, J.; Klir, D.; Rezac, K.; Scholz, M.; Paduch, M.; Ivanova-Stanik, I.; Karpinski, L.; Tomaszewski, K.

    2009-01-21

    This paper summarized the results of interferometry, X-ray and neutron diagnostics performed at the plasma focus facility filled with deuterium. The fusion processes are produced mainly in the dense and hot spherical structure of 2 cm diameter 5-8 cm in front of the anode. The electron temperature of this structure is about 750 eV and the density 5x10{sup 24}-5x10{sup 25}. The neutron energy distribution was calculated using time of flight analysis and showed the dominant direction of the fast deuteron velocity downstream. The deuteron energy distribution was estimated supposing isotropy distribution of the sum of opposite orientation. The total number of fast deuterons in the energy range of 10-400 keV is about 10{sup 18} with total energy of 20 kJ. Plasma in the spherical structure is heated dominantly with ion-ion Coulomb collisions of fast deuterons in the energy range below 10 keV.

  11. Spectral Emission of fast non-Maxwellian Atoms at metallic Surfaces in low density Plasmas

    NASA Astrophysics Data System (ADS)

    Dickheuer, Sven; Marchuk, Oleksandr; Brandt, Christian; Pospieszczyk, Albrecht

    2016-09-01

    We have observed Doppler shifted components of the Balmer-lines emitted by fast non-Maxwellian atoms using different targets in a linear magnetized plasma in the PSI-2 device. In a pure hydrogen plasma the Doppler shifted components of the Balmer emission lines cannot be detected above the signal-to-noise-ratio. However, in a mixed H/Ar plasma with composition of 1:1 the Doppler red- and blue-shifted components can be clearly observed. The Balmer-lines are analyzed by optical emission spectroscopy at observations angles of 35° and 90°. For target materials we use Ag, Pd, Fe and C. An acceleration potential can be applied to the target to change the kinetic energy of the incoming ions between 40 and 200 eV enabling the observation of the Doppler shifted components. The emission mechanism is discussed in details and is probably due to excitation transfer from metastable argon atoms to the fast hydrogen atoms. The Doppler shifted signal can be used to determine the properties of the surfaces, e.g., the energy and angular distribution of reflected atoms. Also the spectral reflectance of the target surface can be obtained and tested against the reference data and measurements with light calibration sources.

  12. High Voltage, Fast-Switching Module for Active Control of Magnetic Fields and Edge Plasma Currents

    NASA Astrophysics Data System (ADS)

    Ziemba, Timothy; Miller, Kenneth; Prager, James; Slobodov, Ilia

    2016-10-01

    Fast, reliable, real-time control of plasma is critical to the success of magnetic fusion science. High voltage and current supplies are needed to mitigate instabilities in all experiments as well as disruption events in large scale tokamaks for steady-state operation. Silicon carbide (SiC) MOSFETs offer many advantages over IGBTs including lower drive energy requirements, lower conduction and switching losses, and higher switching frequency capabilities; however, these devices are limited to 1.2-1.7 kV devices. As fusion enters the long-pulse and burning plasma eras, efficiency of power switching will be important. Eagle Harbor Technologies (EHT), Inc. developing a high voltage SiC MOSFET module that operates at 10 kV. This switch module utilizes EHT gate drive technology, which has demonstrated the ability to increase SiC MOSFET switching efficiency. The module will allow more rapid development of high voltage switching power supplies at lower cost necessary for the next generation of fast plasma feedback and control. EHT is partnering with the High Beta Tokamak group at Columbia to develop detailed high voltage module specifications, to ensure that the final product meets the needs of the fusion science community.

  13. Dietary Sulfur Amino Acid Effects on Fasting Plasma Cysteine/Cystine Redox Potential in Humans

    PubMed Central

    Jones, Dean P.; Park, Youngja; Gletsu-Miller, Nana; Liang, Yongliang; Yu, Tianwei; Accardi, Carolyn Jonas; Ziegler, Thomas R.

    2010-01-01

    Objective Oxidation of plasma cysteine/cystine (Cys/CySS) redox potential (EhCySS) has been associated with risk factors for cardiovascular disease in humans. Cys and CySS are derived from dietary sulfur amino acids (SAA), but the specific effects of SAA depletion and repletion on Cys/CySS redox indices are unknown. The present study examined the effect of dietary SAA intake level on free Cys, free CySS and EhCySS in human plasma under fasting conditions. Research Methods and Procedures Healthy individuals aged 18–36 y (n=13) were equilibrated to foods providing the RDA for SAA and then fed chemically defined diets without SAA (0 mg·kg−1·d−1; n=13) followed by SAA at levels approximating the mean (56 mg·kg−1·d−1; n=8) or 99th percentile (117 mg·kg−1·d−1; n=5) intake levels of Americans. Fasting plasma samples were collected daily during 4-d study periods and analyzed for free Cys, free CySS and the EhCySS. Results The SAA-free diet significantly (p<0.05) decreased plasma free Cys concentrations and oxidized EhCySS values after 4 days of SAA depletion. With SAA repletion at 56 mg·kg−1·d− 1, plasma free Cys increased significantly and values for EhCySS became more reducing. Administration of a diet providing a higher dose of SAA (117 mg·kg−1·d−1) resulted in a significantly higher level of free Cys and a more reducing EhCySS. Conclusions These results show that free Cys and Cys/CySS redox potential (EhCySS) in fasting plasma are affected by dietary SAA intake level in humans. Significant changes occur slowly over 4 days with insufficient SAA intake, but rapidly (after 1 day) with repletion. PMID:20471805

  14. Increased fasting plasma acylation-stimulating protein concentrations in nephrotic syndrome.

    PubMed

    Ozata, Metin; Oktenli, Cagatay; Gulec, Mustafa; Ozgurtas, Taner; Bulucu, Fatih; Caglar, Kayser; Bingol, Necati; Vural, Abdulgaffar; Ozdemir, I Caglayan

    2002-02-01

    Acylation-stimulating protein (ASP) is an adipocyte-derived protein that has recently been suggested to play an important role in the regulation of lipoprotein metabolism and triglyceride (TG) storage. ASP also appears to have a role in the regulation of energy balance. In addition to its role as a hormonal regulator of body weight and energy expenditure, leptin is now implicated as a regulatory molecule in lipid metabolism. However, little is known about the alterations in fasting plasma ASP and leptin concentrations in the nephrotic syndrome. As hyperlipidemia is one of the most striking manifestations of the nephrotic syndrome, we have investigated fasting plasma ASP and leptin levels and their relation to lipid levels in this syndrome. Twenty-five patients with untreated nephrotic syndrome and 25 age-, sex-, and body mass index-matched healthy controls were included in the study. Fasting plasma lipoproteins, TG, total cholesterol, lipoprotein(a), apolipoprotein AI (apoAI), apoB, urinary protein, plasma albumin, third component of complement (C3), ASP, and leptin levels were measured in both groups. Total cholesterol, TG, low and very low density lipoproteins, lipoprotein(a), apoB, and urinary protein levels were increased in the patient group, whereas plasma albumin, high density lipoprotein cholesterol, and apoAI levels were decreased compared with those in the control group (P < 0.001). Plasma ASP levels were significantly higher in the patient group compared with the control subjects (133.72 +/- 65.14 vs. 29.93 +/- 12.68 nmol/liter; P < 0.001), whereas leptin (2.69 +/- 2.06 vs. 3.99 +/- 2.99 ng/ml; P = 0.118) and C3 (1.01 +/- 0.25 vs. 1.06 +/- 0.23 g/liter; P = 0.662) levels were not significantly different between the two groups. Plasma leptin levels were correlated with body mass index in both nephrotic patients (r(s) = 0.86; P < 0.001) and controls (r(s) = 0.98; P < 0.001), but were not correlated with the other parameters. Fasting ASP concentrations

  15. CHARACTERISTICS OF A FAST RISE TIME POWER SUPPLY FOR A PULSED PLASMA REACTOR FOR CHEMICAL VAPOR DESTRUCTION

    EPA Science Inventory

    Rotating spark gap devices for switching high-voltage direct current (dc) into a corona plasma reactor can achieve pulse rise times in the range of tens of nanoseconds. The fast rise times lead to vigorous plasma generation without sparking at instantaneous applied voltages highe...

  16. Effects of prolonged fasting on plasma cortisol and TH in postweaned northern elephant seal pups

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Wade, C. E.; Ortiz, C. L.

    2001-01-01

    Northern elephant seal (Mirounga angustirostris) pups rely on the oxidation of fat stores as their primary source of energy during their 8- to 12-wk postweaning fast; however, potential endocrine mechanisms involved with this increased fat metabolism have yet to be examined. Therefore, 15 pups were serially blood sampled in the field during the first 7 wk of their postweaning fast to examine the changes in plasma concentrations of cortisol and thyroid hormones (TH), which are involved in fat metabolism in other mammals. Cortisol increased, indicating that it contributed to an increase in lipolysis. Increased total triiodothyronine (tT(3)) and thyroxine (tT(4)) may not reflect increased thyroid gland activity, but rather alterations in hormone metabolism. tT(3)-to-tT(4) ratio decreased, suggesting a decrease in thyroxine (T(4)) deiodination, whereas the negative correlation between total proteins and free T(4) suggests that the increase in free hormone is attributed to a decrease in binding globulins. Changes in TH are most similar to those observed during hibernation than starvation in mammals, suggesting that the metabolic adaptations to natural fasting are more similar to hibernation despite the fact these animals remain active throughout the fasting period.

  17. Photoconductive Detectors with Fast Temporal Response for Laser Produced Plasma Experiments.

    SciTech Connect

    May, M; Halvorson, C; Perry, T; Weber, F; Young, P; Silbernagel, C

    2008-05-06

    Processes during laser plasma experiments typically have time scales that are less than 100 ps. The measurement of these processes requires X-ray detectors with fast temporal resolution. We have measured the temporal responses and linearity of several different X-ray sensitive Photoconductive Detectors (PCDs). The active elements of the detectors investigated include both diamond (natural and synthetic) and GaAs crystals. The typical time responses of the GaAs PCDs are approximately 60 ps, respectively. Some characterizations using X-ray light from a synchrotron light source are presented.

  18. Photoconductive Detectors with Fast Temporal Response for Laser Produced Plasma Experiments

    SciTech Connect

    M. J. May, C. Halvorson, T. Perry, F. Weber, P. Young, C. Silbernagel

    2008-06-01

    Processes during laser plasma experiments typically have time scales that are less than 100 ps. The measurement of these processes requires X-ray detectors with fast temporal resolution. We have measured the temporal responses and linearity of several different Xray sensitive Photoconductive Detectors (PCDs). The active elements of the detectors investigated include both diamond (natural and synthetic) and GaAs crystals. The typical time responses of the GaAs PCDs are approximately 60 ps, respectively. Some characterizations using X-ray light from a synchrotron light source are presented.

  19. Photoconductive detectors with fast temporal response for laser produced plasma experiments.

    PubMed

    May, M J; Halvorson, C; Perry, T; Weber, F; Young, P; Silbernagel, C

    2008-10-01

    Processes during laser plasma experiments typically have time scales that are less than 100 ps. The measurement of these processes requires x-ray detectors with fast temporal resolution. We have measured the temporal responses and linearity of several different x-ray sensitive photoconductive detectors (PCDs). The active elements of the detectors investigated include both diamond (natural and synthetic) and GaAs crystals. The typical time responses of the GaAs PCDs are approximately 60 ps, respectively. Some characterizations using x-ray radiation from a synchrotron radiation source are presented.

  20. A fast model for spreading of neutral particles injected locally into hot plasma

    SciTech Connect

    Tokar, M. Z.

    2014-08-15

    A fast model for calculation of non-stationary 3-D profiles of the density for neutral particles locally released into a hot plasma is elaborated. The approach reduces non-stationary three-dimensional transport equations to a set of one-dimensional ones describing the time evolution of the radial profiles for several parameters characterizing adequately the three-dimensional structure. The method is applied to model the spreading process of carbon atoms released by laser desorption in an experimental device and the local injection of working gas into a fusion reactor. The associated heat loads onto the first wall are assessed.

  1. Fast electron energy deposition in a magnetized plasma: Kinetic theory and particle-in-cell simulation

    SciTech Connect

    Robiche, J.; Rax, J.-M.; Bonnaud, G.; Gremillet, L.

    2010-03-15

    The collisional dynamics of a relativistic electron jet in a magnetized plasma are investigated within the framework of kinetic theory. The relativistic Fokker-Planck equation describing slowing down, pitch angle scattering, and cyclotron rotation is derived and solved. Based on the solution of this Fokker-Planck equation, an analytical formula for the root mean square spot size transverse to the magnetic field is derived and this result predicts a reduction in radial transport. Some comparisons with particle-in-cell simulation are made and confirm striking agreement between the theory and the simulation. For fast electron with 1 MeV typical kinetic energy interacting with a solid density hydrogen plasma, the energy deposition density in the transverse direction increases by a factor 2 for magnetic field of the order of 1 T. Along the magnetic field, the energy deposition profile is unaltered compared with the field-free case.

  2. Fast ion generation and bulk plasma heating with three-ion ICRF scenarios

    NASA Astrophysics Data System (ADS)

    Kazakov, Ye. O.; Van Eester, D.; Dumont, R.; Ongena, J.; Lerche, E.; Messiaen, A.

    2015-12-01

    Launching electromagnetic waves in the ion cyclotron range of frequencies (ICRF) is an efficient method of plasma heating, actively employed in most of fusion machines. ICRF has a number of important supplementary applications, including the generation of high-energy ions. In this paper, we discuss a new set of three-ion ICRF scenarios and the prospect of their use as a dedicated tool for fast ion generation in tokamaks and stellarators. A distinct feature of these scenarios is a strong absorption efficiency possible at very low concentrations of resonant minority ions (˜ 1% or even below). Such concentration levels are typical for impurities contaminating fusion plasmas. An alternative ICRF scenario for maximizing the efficiency of bulk D-T ion heating is suggested for JET and ITER tokamaks, which is based on three-ion ICRF heating of intrinsic Beryllium impurities.

  3. Be Foil "Filter Knee Imaging" NSTX Plasma with Fast Soft X-ray Camera

    SciTech Connect

    B.C. Stratton; S. von Goeler; D. Stutman; K. Tritz; L.E. Zakharov

    2005-08-08

    A fast soft x-ray (SXR) pinhole camera has been implemented on the National Spherical Torus Experiment (NSTX). This paper presents observations and describes the Be foil Filter Knee Imaging (FKI) technique for reconstructions of a m/n=1/1 mode on NSTX. The SXR camera has a wide-angle (28{sup o}) field of view of the plasma. The camera images nearly the entire diameter of the plasma and a comparable region in the vertical direction. SXR photons pass through a beryllium foil and are imaged by a pinhole onto a P47 scintillator deposited on a fiber optic faceplate. An electrostatic image intensifier demagnifies the visible image by 6:1 to match it to the size of the charge-coupled device (CCD) chip. A pair of lenses couples the image to the CCD chip.

  4. Fast ion generation and bulk plasma heating with three-ion ICRF scenarios

    SciTech Connect

    Kazakov, Ye. O. Van Eester, D.; Ongena, J.; Lerche, E.; Messiaen, A.

    2015-12-10

    Launching electromagnetic waves in the ion cyclotron range of frequencies (ICRF) is an efficient method of plasma heating, actively employed in most of fusion machines. ICRF has a number of important supplementary applications, including the generation of high-energy ions. In this paper, we discuss a new set of three-ion ICRF scenarios and the prospect of their use as a dedicated tool for fast ion generation in tokamaks and stellarators. A distinct feature of these scenarios is a strong absorption efficiency possible at very low concentrations of resonant minority ions (∼ 1% or even below). Such concentration levels are typical for impurities contaminating fusion plasmas. An alternative ICRF scenario for maximizing the efficiency of bulk D-T ion heating is suggested for JET and ITER tokamaks, which is based on three-ion ICRF heating of intrinsic Beryllium impurities.

  5. Shear flow instability in a partially-ionized plasma sheath around a fast-moving vehicle

    SciTech Connect

    Sotnikov, V. I.; Mudaliar, S.; Genoni, T. C.; Rose, D. V.; Oliver, B. V.; Mehlhorn, T. A.

    2011-06-15

    The stability of ion acoustic waves in a sheared-flow, partially-ionized compressible plasma sheath around a fast-moving vehicle in the upper atmosphere, is described and evaluated for different flow profiles. In a compressible plasma with shear flow, instability occurs for any velocity profile, not just for profiles with an inflection point. A second-order differential equation for the electrostatic potential of excited ion acoustic waves in the presence of electron and ion collisions with neutrals is derived and solved numerically using a shooting method with boundary conditions appropriate for a finite thickness sheath in contact with the vehicle. We consider three different velocity flow profiles and find that in all cases that neutral collisions can completely suppress the instability.

  6. Plasma flow and fast particles in a hypervelocity accelerator - A color presentation. [micrometeoroid simulation

    NASA Technical Reports Server (NTRS)

    Igenbergs, E. B.; Cour-Palais, B.; Fisher, E.; Stehle, O.

    1975-01-01

    A new concept for particle acceleration for micrometeoroid simulation was developed at NASA Marshall Space Flight Center, using a high-density self-luminescent fast plasma flow to accelerate glass beads (with a diameter up to 1.0 mm) to velocities between 15-20 km/sec. After a short introduction to the operation of the hypervelocity range, the eight-converter-camera unit used for the photographs of the plasma flow and the accelerated particles is described. These photographs are obtained with an eight-segment reflecting pyramidal beam splitter. Wratten filters were mounted between the beam splitter and the converter tubes of the cameras. The photographs, which were recorded on black and white film, were used to make the matrices for the dye-color process, which produced the prints shown.

  7. Magnetized Fast ignition (MFI) and Laser Plasma Interactions in Strong Magnetic Field

    NASA Astrophysics Data System (ADS)

    Mima, Kunioki; Johzaki, T.; Honrubia, J.; Nagatomo, H.; Taguchi, T.; Sunahara, A.; Sakagami, H.; Fujioka, S.; Logan, G.

    2016-03-01

    In this paper, magnetized fast ignition (MFI) is proposed for improving the coupling efficiency of a heating laser to a core plasma. In the MFI, the external magnetic field is applied to reduce the hot electron energy and focus the dense hot electron flux to the core. The external magnetic field higher than 100T is generated by the laser driven coil and it is amplified by the implosion. The magnetic field at the tip of the cone is expected to reach higher than 10kT and the laser plasma interaction and the hot electron transport are modified. As the results of applying the external magnetic field, hot electron energy is reduced to less than 5MeV for the laser intensity of 1020W/ cm2 and the Weibel instability is suppressed to collimate the hot electron beam to the core.

  8. The development and testing of the fast imaging plasma spectrometer and its application in the plasma environment at Mercury

    NASA Astrophysics Data System (ADS)

    Koehn, Patrick Leo

    The plasma environment at Mercury is a rich laboratory for studying the interaction of the solar wind with a planet. Three primary populations of ions exist at Mercury: solar wind, magnetospheric particles, and pickup ions. Pickup ions are generated through the ionization of Mercury's exosphere or are sputtered particles from the Mercury surface. A comprehensive mission to Mercury should include a sensor that is able to determine the dynamical properties and composition of all three plasma components. The Fast Imaging Plasma Spectrometer (FIPS) is an instrument to measure the composition of these ion populations and their three-dimensional velocity distribution functions. It is lightweight, fast, and has a very large field of view, and these properties made possible its accommodation within the highly mass- constrained payload of MESSENGER (MErcury: Surface, Space ENvironment, GEochemistry, Ranging) mission, a Mercury orbiter. This work details the development cycle of FIPS, from concept to prototype testing. It begins with science studies of the magnetospheric and pickup ion environments of Mercury, using state-of-the-art computer simulations to produce static and quasi-dynamic magnetospheric systems. Predictions are made of the spatially variable plasma environment at Mercury, and the temporally varying magnetosphere-solar wind interaction is examined. Pickup ion studies provide insights to particle loss mechanisms and the nature of the radar-bright regions at the Hermean poles. These studies produce science requirements for successfully measuring this environment with an orbiting mass spectrometer. With these science requirements in mind, a concept for a new electrostatic analyzer is created. This concept is considered from a theoretical standpoint, and compared with other, similarly performing instruments, both of the past and currently in use. The development cycle continues with instrument simulation, which allows the design to be adjusted to fit within the

  9. PERFORMANCE OF A1C VERSUS OGTT FOR THE DIAGNOSIS OF PREDIABETES IN A COMMUNITY-BASED SCREENING

    PubMed Central

    Camacho, Jenny E.; Shah, Vallabh O.; Schrader, Ronald; Wong, Craig S.; Burge, Mark R.

    2017-01-01

    Objective Reliable identification of individuals at risk for developing diabetes is critical to instituting preventative strategies. Studies suggest that the accuracy of using A1c as a sole diagnostic criterion for diabetes may be variable across different ethnic groups. We postulate that there will be lack of concordance between A1c and the Oral Glucose Tolerance Test (OGTT) for diagnosing prediabetes across Hispanic and Non-Hispanic White (NHW) populations. Research Design and Methods 218 asymptomatic adults at risk for Type 2 Diabetes (T2D) were assessed with A1c and OGTT for the diagnosis of prediabetes. Glucose homeostasis status was assigned as no diabetes (A1c < 5.7%), prediabetes (A1c 5.7% – 6.4%), and T2D (A1c > 6.4%). Inclusion criteria were age > 18 years and at least one of the following: a family history of diabetes, a history of gestational diabetes, Hispanic ethnicity, non-Caucasian race, or obesity. Subjects received a fasting 75-gram OGTT and A1c on the same day. Bowker’s Test of Symmetry was employed to determine agreement between the tests. Results Data from 99 Hispanic patients and 79 NHW patients were analyzed. There was no concordance between A1c and OGTT for Hispanic (p=0.002) or NHW individuals (p=0.003) with prediabetes. Conclusions A1c is discordant with OGTT among Hispanic and NHW subjects for the diagnosis of prediabetes. Sole use of A1c to designate glycemic status will result in a greater prevalence of prediabetes among Hispanic and NHW New Mexicans. PMID:27482613

  10. Generation of plasma rotation in a tokamak by ion-cyclotron absorption of fast Alfven waves

    SciTech Connect

    F.W. Perkins; R.B. White; P. Bonoli

    2000-06-13

    Control of rotation in tokamak plasmas provides a method for suppressing fine-scale turbulent transport by velocity shear and for stabilizing large-scale magnetohydrodynamic instabilities via a close-fitting conducting shell. The experimental discovery of rotation in a plasma heated by the fast-wave minority ion cyclotron process is important both as a potential control method for a fusion reactor and as a fundamental issue, because rotation arises even though this heating process introduces negligible angular momentum. This paper proposes and evaluates a mechanism which resolves this apparent conflict. First, it is assumed that angular momentum transport in a tokamak is governed by a diffusion equation with a no-slip boundary condition at the plasma surface and with a torque-density source that is a function of radius. When the torque density source consists of two separated regions of positive and negative torque density, a non-zero central rotation velocity results, even when the total angular momentum input vanishes. Secondly, the authors show that localized ion-cyclotron heating can generate regions of positive and negative torque density and consequently central plasma rotation.

  11. Laser Channeling in an Inhomogeneous Plasma for Fast-Ignition Laser Fusion

    NASA Astrophysics Data System (ADS)

    Ivancic, S.; Haberberger, D.; Theobald, W.; Anderson, K. S.; Froula, D. H.; Meyerhofer, D. D.; Tanaka, K.; Habara, H.; Iwawaki, T.

    2014-10-01

    The evacuation of a plasma cavity by a high-intensity laser beam is of practical importance to the channeling fast-ignition concept. The channel in the plasma corona of an imploded inertial confinement fusion capsule provides a clear path through the plasma so that the energy from a second high-intensity laser can be deposited close to the dense core of the assembled fuel to achieve ignition. This study reports on experiments that demonstrate the transport of high-intensity (>1017 W/cm2) laser light through an inhomogeneous kilojoule-laser-produced plasma up to overcritical density. The multikilojoule high-intensity light evacuates a cavity inside the focal spot, leaving a parabolic trough that is observed using a novel optical probing technique--angular filter refractometery. The cavity forms in less than 100 ps using a 20-TW laser pulse and bores at a velocity of ~ 2 μm/ps. The experimentally measured depths of the cavity are consistent with a ponderomotive hole-boring model. The experiments show that 100-ps IR pulses with an intensity of ~ 5 ×1017 W/cm2 produced a channel up to the critical density, while 10-ps pulses with the same energy but higher intensity did not propagate as far. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  12. Shifting from glucose diagnosis to the new HbA1c diagnosis reduces the capability of the Finnish Diabetes Risk Score (FINDRISC) to screen for glucose abnormalities within a real-life primary healthcare preventive strategy

    PubMed Central

    2013-01-01

    Background To investigate differences in the performance of the Finnish Diabetes Risk Score (FINDRISC) as a screening tool for glucose abnormalities after shifting from glucose-based diagnostic criteria to the proposed new hemoglobin (Hb)A1c-based criteria. Methods A cross-sectional primary-care study was conducted as the first part of an active real-life lifestyle intervention to prevent type 2 diabetes within a high-risk Spanish Mediterranean population. Individuals without diabetes aged 45-75 years (n = 3,120) were screened using the FINDRISC. Where feasible, a subsequent 2-hour oral glucose tolerance test and HbA1c test were also carried out (n = 1,712). The performance of the risk score was calculated by applying the area under the curve (AUC) for the receiver operating characteristic, using three sets of criteria (2-hour glucose, fasting glucose, HbA1c) and three diagnostic categories (normal, pre-diabetes, diabetes). Results Defining diabetes by a single HbA1c measurement resulted in a significantly lower diabetes prevalence (3.6%) compared with diabetes defined by 2-hour plasma glucose (9.2%), but was not significantly lower than that obtained using fasting plasma glucose (3.1%). The FINDRISC at a cut-off of 14 had a reasonably high ability to predict diabetes using the diagnostic criteria of 2-hour or fasting glucose (AUC = 0.71) or all glucose abnormalities (AUC = 0.67 and 0.69, respectively). When HbA1c was used as the primary diagnostic criterion, the AUC for diabetes detection dropped to 0.67 (5.6% reduction in comparison with either 2-hour or fasting glucose) and fell to 0.55 for detection of all glucose abnormalities (17.9% and 20.3% reduction, respectively), with a relevant decrease in sensitivity of the risk score. Conclusions A shift from glucose-based diagnosis to HbA1c-based diagnosis substantially reduces the ability of the FINDRISC to screen for glucose abnormalities when applied in this real-life primary-care preventive strategy. PMID

  13. Burden of Diabetes and First Evidence for the Utility of HbA1c for Diagnosis and Detection of Diabetes in Urban Black South Africans: The Durban Diabetes Study

    PubMed Central

    Hird, Thomas R.; Pirie, Fraser J.; Esterhuizen, Tonya M.; O’Leary, Brian; McCarthy, Mark I.; Young, Elizabeth H.; Sandhu, Manjinder S.; Motala, Ayesha A.

    2016-01-01

    Objective Glycated haemoglobin (HbA1c) is recommended as an additional tool to glucose-based measures (fasting plasma glucose [FPG] and 2-hour plasma glucose [2PG] during oral glucose tolerance test [OGTT]) for the diagnosis of diabetes; however, its use in sub-Saharan African populations is not established. We assessed prevalence estimates and the diagnosis and detection of diabetes based on OGTT, FPG, and HbA1c in an urban black South African population. Research Design and Methods We conducted a population-based cross-sectional survey using multistage cluster sampling of adults aged ≥18 years in Durban (eThekwini municipality), KwaZulu-Natal. All participants had a 75-g OGTT and HbA1c measurements. Receiver operating characteristic (ROC) analysis was used to assess the overall diagnostic accuracy of HbA1c, using OGTT as the reference, and to determine optimal HbA1c cut-offs. Results Among 1190 participants (851 women, 92.6% response rate), the age-standardised prevalence of diabetes was 12.9% based on OGTT, 11.9% based on FPG, and 13.1% based on HbA1c. In participants without a previous history of diabetes (n = 1077), using OGTT as the reference, an HbA1c ≥48 mmol/mol (6.5%) detected diabetes with 70.3% sensitivity (95%CI 52.7–87.8) and 98.7% specificity (95%CI 97.9–99.4) (AUC 0.94 [95%CI 0.89–1.00]). Additional analyses suggested the optimal HbA1c cut-off for detection of diabetes in this population was 42 mmol/mol (6.0%) (sensitivity 89.2% [95%CI 78.6–99.8], specificity 92.0% [95%CI: 90.3–93.7]). Conclusions In an urban black South African population, we found a high prevalence of diabetes and provide the first evidence for the utility of HbA1c for the diagnosis and detection of diabetes in black Africans in sub-Saharan Africa. PMID:27560687

  14. Catechol-O-methyltransferase association with hemoglobin A1c

    PubMed Central

    Hall, Kathryn T.; Jablonski, Kathleen A.; Chen, Ling; Harden, Maegan; Tolkin, Benjamin R.; Kaptchuk, Ted J.; Bray, George A.; Ridker, Paul M.; Florez, Jose C.; Chasman, Daniel I.

    2016-01-01

    Aims Catecholamines have metabolic effects on blood pressure, insulin sensitivity and blood glucose. Genetic variation in catechol-O-methyltransferase (COMT), an enzyme that degrades catecholamines, is associated with cardiometabolic risk factors and incident cardiovascular disease (CVD). Here we examined COMT effects on glycemic function and type 2 diabetes. Methods We tested whether COMT polymorphisms were associated with baseline HbA1c in the Women’s Genome Health Study (WGHS), and Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC), and with susceptibility to type 2 diabetes in WGHS, DIAbetes Genetics Replication And Meta-analysis consortium (DIAGRAM), and the Diabetes Prevention Program (DPP). Given evidence that COMT modifies some drug responses, we examined association with type 2 diabetes and randomized metformin and aspirin treatment. Results COMT rs4680 high-activity G-allele was associated with lower HbA1c in WGHS (β = −0.032% [0.012], p = 0.008) and borderline significant in MAGIC (β = −0.006% [0.003], p = 0.07). Combined COMT per val allele effects on type 2 diabetes were significant (OR = 0.98 [0.96–0.998], p = 0.03) in fixed-effects analyses across WGHS, DIAGRAM, and DPP. Similar results were obtained for 2 other COMT SNPs rs4818 and rs4633. In the DPP, the rs4680 val allele was borderline associated with lower diabetes incidence among participants randomized to metformin (HR = 0.81 [0.65–1.00], p = 0.05). Conclusions COMT rs4680 high-activity G-allele was associated with lower HbA1c and modest protection from type 2 diabetes. The directionality of COMT associations was concordant with those previously observed for cardiometabolic risk factors and CVD. PMID:27282867

  15. Reliability of fasting plasma alkylresorcinol metabolites concentrations measured 4 months apart.

    PubMed

    Montonen, J; Landberg, R; Kamal-Eldin, A; Åman, P; Boeing, H; Steffen, A; Pischon, T

    2012-08-01

    Alkylresorcinols (AR) have been suggested as specific dietary biomarkers of whole-grain wheat and rye intake. AR are metabolised to 3,5-dihydroxybenzoic acid (DHBA) and 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA), which have longer apparent half-lives and were recently proposed to better reflect long-term whole-grain consumption than the intact AR. The objective of this study was to analyse the reliability--expressed by the intraclass correlation coefficient (ICC)--of AR metabolite concentrations among 100 participants from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam study who provided two fasting plasma samples 4 months apart. DHBA and DHPPA concentrations were not significantly different between the first and second measurement over the 4-month period (P>0.05). The ICC was 0.32 (95% confidence interval (CI)=0.13-0.49) for DHBA and 0.37 (95%CI=0.19-0.53) for DHPPA. These results suggest that AR metabolites cannot be considered to be better biomarkers of whole-grain wheat and rye intake than the intact AR in fasting plasma (ICC=0.42).

  16. Renal responses to plasma volume expansion and hyperosmolality in fasting seal pups

    NASA Technical Reports Server (NTRS)

    Ortiz, Rudy M.; Wade, Charles E.; Costa, Daniel P.; Ortiz, C. Leo

    2002-01-01

    Renal responses were quantified in northern elephant seal (Mirounga angustirostris) pups during their postweaning fast to examine their excretory capabilities. Pups were infused with either isotonic (0.9%; n = 8; Iso) or hypertonic (16.7%; n = 7; Hyper) saline via an indwelling catheter such that each pup received 3 mmol NaCl/kg. Diuresis after the infusions was similar in magnitude between the two treatments. Osmotic clearance increased by 37% in Iso and 252% in Hyper. Free water clearance was reduced 3.4-fold in Hyper but was not significantly altered in Iso. Glomerular filtration rate increased 71% in the 24-h period after Hyper, but no net change occurred during the same time after Iso. Natriuresis increased 3.6-fold in Iso and 5.3-fold in Hyper. Iso decreased plasma arginine vasopressin (AVP) and cortisol acutely, whereas Hyper increased plasma and excreted AVP and cortisol. Iso was accompanied by the retention of water and electrolytes, whereas the Hyper load was excreted within 24 h. Natriuresis is attributed to increased filtration and is independent of an increase in atrial natriuretic peptide and decreases in ANG II and aldosterone. Fasting pups appear to have well-developed kidneys capable of both extreme conservation and excretion of Na(+).

  17. Diagnostics of fast formation of distributed plasma discharges using X-band microwaves

    SciTech Connect

    Xiang, X. Kupczyk, B.; Booske, J.; Scharer, J.

    2014-02-14

    We present measurements of high power (25.7 kW), pulsed (800 ns), X-band (9.382 GHz) microwave breakdown plasmas, including reflected power measurements, mixer reflected amplitude and phase measurements, optical emission spectroscopy (OES) measurements, and an analysis that estimates the average electron density and electron temperature. In addition, a six-region, 1-D model was used to determine plasma parameters and compare with the experimental results. The experimental results show that using a 43 Hz repetition rate with an 800 ns pulse, fast (<300 ns) breakdown occurs in neon measured between 50 Torr and 250 Torr, producing plasma that lasts for over 7 μs. It also leads to large microwave reflections (70%) and an on-axis transmission attenuation of −15 dB. Moreover, a comparison between a 1-D model and mixer measurements shows that at 100 Torr, the neon plasma electron density peaked at 2 × 10{sup 12} cm{sup −3}, and the electron temperature peaked at 2.5 eV assuming a Maxwellian distribution. The addition of 2% Ar in Ne reduced the breakdown time and allowed OES measurements to determine the effective electron temperature. OES measurements of mixed (Ne/Ar: 98/2) argon line ratios (420.1 nm/419.8 nm) were used to determine the average effective electron temperature T{sub e(eff)} = 1.2 eV, averaged over the entire 7μs plasma lifetime. They indicate that the electron energy distribution was not Maxwellian but, instead, tended towards a Druyvesteyn character.

  18. Effect of the long-term regular intake of virgin olive oil on the phenolic metabolites in human fasting plasma.

    PubMed

    Valls, Rosa-Maria; Soler, Aranzazu; Girona, Josefa; Heras, Mercedes; Romero, Maria-Paz; Covas, Maria-Isabel; Solà, Rosa; Masana, Lluis; Motilva, Maria-Jose

    2010-09-21

    The effect of repeated consumption of virgin olive oil on endogenous phenolic metabolites of fasting plasma is unknown. For this reason, we hypothesized that regular long-term virgin olive oil intake could have an indirect protection effect on the endogenous phenols. Thus, the aim of the study was to determine the phenolic profile of human plasma in a fasting state of long-term regular virgin olive oil consumers, using the fasting plasma of non-consumers as a natural control. Forty participants living in the area of Reus (Catalonia, Spain) were selected, 20 life-long regular consumers of virgin olive oil and a natural control of 20 non-consumers, the latter being Rumanians who dislike the taste of olive oil. The diet was obtained from 3-day food records. The results showed similar phenolic composition of fasting plasmas of the two volunteer groups. Of special interest is that more of the compounds quantified showed higher concentration in fasting plasma from habitual virgin olive oil consumers. The compounds were semi-quantified using caffeic acid as the calibration standard. The quantification of fasting consumer's plasma showed higher concentration of a hydroxyflavanone type compound (2.90+/-0.04 microM vs 1.5+/-0.04 microM) and a catecholamine derivative (0.70+/-0.03 microM vs 0.56+/-0.03 microM) than the plasma of non-consumers (P<0.05). The results suggest an indirect protective mechanism of long-term regular virgin olive oil consumption related to the protection of the endogenous antioxidant system.

  19. Impact of diabetes duration on achieved reductions in glycated haemoglobin, fasting plasma glucose and body weight with liraglutide treatment for up to 28 weeks: a meta‐analysis of seven phase III trials

    PubMed Central

    Bailey, T.; Barkholt Christensen, S.; Nauck, M. A.

    2016-01-01

    This meta‐analysis of seven randomized, placebo‐controlled studies (total 3222 patients) evaluated whether type 2 diabetes (T2D) duration affects the changes in blood glucose control and body weight that can be achieved with liraglutide and placebo. With liraglutide 1.2 mg, shorter diabetes duration was associated with a significantly greater, but clinically non‐relevant, difference in glycated haemoglobin (HbA1c) reduction (p < 0.05), i.e. a 0.18% (1.96 mmol/mol) reduction in HbA1c per 10 years shorter diabetes duration. With liraglutide 1.8 mg, shorter diabetes duration was associated with a small but statistically significant trend for greater fasting plasma glucose (FPG) reduction (p < 0.05), i.e. a 0.38 mmol/l reduction in FPG per 10 years shorter diabetes duration. Neither the liraglutide 1.8 mg nor placebo results showed a significant association between HbA1c and diabetes duration and neither the liraglutide 1.2 mg nor placebo results showed a significant association between FPG and diabetes duration. Likewise, neither liraglutide nor placebo showed a significant association between change in weight and diabetes duration. These results suggest diabetes duration has a clinically negligible effect on achievable blood glucose control and weight outcomes with liraglutide and placebo in patients with T2D. PMID:26679282

  20. Association of HbA1c and cardiovascular and renal disease in an adult Mediterranean population

    PubMed Central

    2013-01-01

    Background Increasing evidence suggests a mechanistic link between the glycemic environment and renal and cardiovascular events, even below the threshold for diabetes. We aimed to assess the association between HbA1c and chronic kidney disease (CKD) and cardiovascular disease (CVD). Methods A cross-sectional study involving a random representative sample of 2270 adults from southern Spain (Malaga) was undertaken. We measured HbA1c, serum creatinine and albuminuria in fasting blood and urine samples. Results Individuals without diabetes in the upper HbA1c tertile had an unfavorable cardiovascular and renal profile and shared certain clinical characteristics with the patients with diabetes. Overall, a higher HbA1c concentration was strongly associated with CKD or CVD after adjustment for traditional risk factors. The patients with known diabetes had a 2-fold higher odds of CKD or CVD. However, when both parameters were introduced in the same model, the HbA1c concentration was only significantly associated with clinical endpoints (OR: 1.4, 95% CI, 1.1-1.6, P = 0.002). An increase in HbA1c of one percentage point was associated with a 30% to 40% increase in the rate of CKD or CVD. This relationship was apparent in persons with and without known diabetes. ROC curves illustrated that a HbA1c of 37 mmol/mol (5.5%) was the optimal value in terms of sensitivity and specificity for predicting endpoints in this population. Conclusion HbA1c levels were associated with a higher prevalence of CKD and CVD cross-sectionally, regardless of diabetes status. These data support the value of HbA1c as a marker of cardiovascular and renal disease in the general population. PMID:23865389

  1. Fast magnetic twister and plasma perturbations in a three-dimensional coronal arcade

    SciTech Connect

    Murawski, K.; Srivastava, A. K.; Musielak, Z. E. E-mail: asrivastava.app@iitbhu.ac.in E-mail: musielak@kis.uni-freiburg.de

    2014-06-10

    We present results of three-dimensional (3D) numerical simulations of a fast magnetic twister excited above a foot-point of the potential solar coronal arcade that is embedded in the solar atmosphere with the initial VAL-IIIC temperature profile, which is smoothly extended into the solar corona. With the use of the FLASH code, we solve 3D ideal magnetohydrodynamic equations by specifying a twist in the azimuthal component of magnetic field in the solar chromosphere. The imposed perturbation generates torsional Alfvén waves as well as plasma swirls that reach the other foot-point of the arcade and partially reflect back from the transition region. The two vortex channels are evident in the generated twisted flux-tube with a fragmentation near its apex which results from the initial twist as well as from the morphology of the tube. The numerical results are compared to observational data of plasma motions in a solar prominence. The comparison shows that the numerical results and the data qualitatively agree even though the observed plasma motions occur over comparatively large spatio-temporal scales in the prominence.

  2. Relationships between fasting plasma insulin, anthropometrics, and metabolic parameters in a very old healthy population. Associazione Medica Sabin.

    PubMed

    Carantoni, M; Zuliani, G; Volpato, S; Palmieri, E; Mezzetti, A; Vergnani, L; Fellin, R

    1998-05-01

    Several studies have shown that insulin resistance and hyperinsulinemia are associated with many metabolic disorders predisposing to coronary heart disease (CHD). This syndrome has been termed syndrome X. However, it is not completely known whether these relationships are still present in the elderly, or whether other factors such as age, gender, and body fat distribution modulate them. Therefore, we investigated the relationship between fasting plasma insulin, total and regional adiposity, fasting plasma glucose and lipids, plasma plasminogen activator inhibitor-1 (PAI-1), fibrinogen, and coagulation factor VII in a sample of 100 healthy free-living octogenarians-nonagenarians (52 men and 48 women) who were disability-free according to the Katz index. By univariate analysis, fasting insulin correlated positively with all anthropometric measures except the waist to hip ratio (WHR) in women. There was a positive correlation between fasting insulin and fasting glucose (r=.40, P < .01), plasma triglycerides ([TGs] r=.21, P < .05), and PAI-1 levels (r=.33, P < .01), whereas a negative relation was found with high-density lipoprotein cholesterol (HDL-C) and apolipoprotein, A-I (apo A-I) levels (r=-.22 and =-.24, respectively, P < .05). These relationships were weaker and less significant in women. In pooled data, stepwise multiple regression analysis showed an independent relationship of both the body mass index (BMI) and fasting insulin level with TGs (R2=.14), while gender and fasting insulin were the best predictors of HDL-C variance (R2=.17). Furthermore, fasting insulin was the only variable independently related to PAI-1 (R2=.12). Our findings support the existence of a metabolic syndrome even in very old age by showing that high insulin levels are related to various metabolic and hemostatic disorders.

  3. Investigating plasma viscosity with fast framing photography in the ZaP-HD Flow Z-Pinch experiment

    NASA Astrophysics Data System (ADS)

    Weed, Jonathan Robert

    The ZaP-HD Flow Z-Pinch experiment investigates the stabilizing effect of sheared axial flows while scaling toward a high-energy-density laboratory plasma (HEDLP > 100 GPa). Stabilizing flows may persist until viscous forces dissipate a sheared flow profile. Plasma viscosity is investigated by measuring scale lengths in turbulence intentionally introduced in the plasma flow. A boron nitride turbulence-tripping probe excites small scale length turbulence in the plasma, and fast framing optical cameras are used to study time-evolved turbulent structures and viscous dissipation. A Hadland Imacon 790 fast framing camera is modified for digital image capture, but features insufficient resolution to study turbulent structures. A Shimadzu HPV-X camera captures the evolution of turbulent structures with great spatial and temporal resolution, but is unable to resolve the anticipated Kolmogorov scale in ZaP-HD as predicted by a simplified pinch model.

  4. Stable isotope models of sugar intake using hair, red blood cells, and plasma, but not fasting plasma glucose, predict sugar intake in a Yup'ik study population.

    PubMed

    Nash, Sarah H; Kristal, Alan R; Hopkins, Scarlett E; Boyer, Bert B; O'Brien, Diane M

    2014-01-01

    Objectively measured biomarkers will help to resolve the controversial role of sugar intake in the etiology of obesity and related chronic diseases. We recently validated a dual-isotope model based on RBC carbon (δ(13)C) and nitrogen (δ(15)N) isotope ratios that explained a large percentage of the variation in self-reported sugar intake in a Yup'ik study population. Stable isotope ratios can easily be measured from many tissues, including RBCs, plasma, and hair; however, it is not known how isotopic models of sugar intake compare among these tissues. Here, we compared self-reported sugar intake with models based on RBCs, plasma, and hair δ(13)C and δ(15)N in Yup'ik people. We also evaluated associations of sugar intake with fasting plasma glucose δ(13)C. Finally, we evaluated relations between δ(13)C and δ(15)N values in hair, plasma, RBCs, and fasting plasma glucose to allow comparison of isotope ratios across tissue types. Models using RBCs, plasma, or hair isotope ratios explained similar amounts of variance in total sugar, added sugar, and sugar-sweetened beverage intake (∼53%, 48%, and 34%, respectively); however, the association with δ(13)C was strongest for models based on RBCs and hair. There were no associations with fasting plasma glucose δ(13)C (R(2) = 0.03). The δ(13)C and δ(15)N values of RBCs, plasma, and hair showed strong, positive correlations; the slopes of these relations did not differ from 1. This study demonstrates that RBC, plasma, and hair isotope ratios predict sugar intake and provides data that will allow comparison of studies using different sample types.

  5. Implications of iron deficiency/anemia on the classification of diabetes using HbA1c

    PubMed Central

    Attard, S M; Herring, A H; Wang, H; Howard, A-G; Thompson, A L; Adair, L S; Mayer-Davis, E J; Gordon-Larsen, P

    2015-01-01

    Background/Objectives: Nonglycemic factors like iron deficiency (ID) or anemia may interfere with classification of diabetes and prediabetes using hemoglobin A1c (HbA1c). However, few population-based studies of diabetes in areas with endemic ID/anemia have been conducted. We aimed to determine how mutually exclusive categories of ID alone, anemia alone and iron-deficiency anemia (IDA) were each associated with prediabetes and diabetes prevalence using fasting blood glucose (FBG) versus HbA1c in a population-based study of adults with endemic ID/anemia. Subjects/Methods: We used data from the China Health and Nutrition Survey, a longitudinal, population-based study across 228 communities within nine provinces of China. This analysis included 7308 adults seen in the 2009 survey aged 18–75 years. We used descriptive and covariate-adjusted models to examine relative risk of prediabetes and diabetes using FBG alone, HbA1c alone, HbA1c and FBG, or neither (normoglycemia) by anemia alone, ID alone, IDA or normal iron/hemoglobin. Results: Approximately 65% of individuals with diabetes in our sample were concordantly classified with diabetes using both FBG and HbA1c, while 35% had a discordant diabetes classification: they were classified using either FBG or HbA1c, but not both. Fewer participants with ID alone versus normal iron/hemoglobin were classified with diabetes using HbA1c only. From covariate-adjusted, multinomial regression analyses, the adjusted prevalence of prediabetes using HbA1c only was 22% for men with anemia alone, but 13% for men with normal iron/hemoglobin. In contrast, the predicted prevalence of prediabetes using HbA1c only was 8% for women with ID alone, compared with 13% for women with normal iron/hemoglobin. Conclusions: These findings suggest potential misclassification of diabetes using HbA1c in areas of endemic ID/anemia. Estimating diabetes prevalence using HbA1c may result in under-diagnosis in women with ID and over-diagnosis in men with

  6. A Novel Glycated Hemoglobin A1c-Lowering Traditional Chinese Medicinal Formula, Identified by Translational Medicine Study

    PubMed Central

    Li, Tsai-Chung; Li, Chia-Cheng; Huang, Hui-Chi; Chen, Jaw-Chyun; Ho, Tin-Yun

    2014-01-01

    Diabetes is a chronic metabolic disorder that has a significant impact on the health care system. The reduction of glycated hemoglobin A1c is highly associated with the improvements of glycemic control and diabetic complications. In this study, we identified a traditional Chinese medicinal formula with a HbA1c-lowering potential from clinical evidences. By surveying 9,973 diabetic patients enrolled in Taiwan Diabetic Care Management Program, we found that Chu-Yeh-Shih-Kao-Tang (CYSKT) significantly reduced HbA1c values in diabetic patients. CYSKT reduced the levels of HbA1c and fasting blood glucose, and stimulated the blood glucose clearance in type 2 diabetic mice. CYSKT affected the expressions of genes associated with insulin signaling pathway, increased the amount of phosphorylated insulin receptor in cells and tissues, and stimulated the translocation of glucose transporter 4. Moreover, CYSKT affected the expressions of genes related to diabetic complications, improved the levels of renal function indexes, and increased the survival rate of diabetic mice. In conclusion, this was a translational medicine study that applied a “bedside-to-bench” approach to identify a novel HbA1c-lowering formula. Our findings suggested that oral administration of CYSKT affected insulin signaling pathway, decreased HbA1c and blood glucose levels, and consequently reduced mortality rate in type 2 diabetic mice. PMID:25133699

  7. Time dependence of fast electron beam divergence in ultraintense laser-plasma interactions.

    PubMed

    Akli, K U; Storm, M J; McMahon, M; Jiang, S; Ovchinnikov, V; Schumacher, D W; Freeman, R R; Dyer, G; Ditmire, T

    2012-08-01

    We report on the measurement and computer simulation of the divergence of fast electrons generated in an ultraintense laser-plasma interaction (LPI) and the subsequent propagation in a nonrefluxing target. We show that, at Iλ(2) of 10(20) Wcm(-2)μm(2), the time-integrated electron beam full divergence angle is (60±5)°. However, our time-resolved 2D particle-in-cell simulations show the initial beam divergence to be much smaller (≤30°). Our simulations show the divergence to monotonically increase with time, reaching a final value of (68±7)° after the passage of the laser pulse, consistent with the experimental time-integrated measurements. By revealing the time-dependent nature of the LPI, we find that a substantial fraction of the laser energy (~7%) is transported up to 100 μm with a divergence of 32°.

  8. Fast differentiation of SIRS and sepsis from blood plasma of ICU patients using Raman spectroscopy.

    PubMed

    Neugebauer, Ute; Trenkmann, Sabine; Bocklitz, Thomas; Schmerler, Diana; Kiehntopf, Michael; Popp, Jürgen

    2014-04-01

    Currently, there is no biomarker that can reliable distinguish between infectious and non-infectious systemic inflammatory response syndrome (SIRS). However, such a biomarker would be of utmost importance for early identification and stratification of patients at risk to initiate timely and appropriate antibiotic treatment. Within this proof of principle study, the high potential of Raman spectroscopy for the fast differentiation of non-infectious SIRS and sepsis is demonstrated. Blood plasma collected from 70 patients from the intensive care unit (31 patients with sepsis and 39 patients classified with SIRS without infection) was analyzed by means of Raman spectroscopy. A PCA-LDA based classification model was trained with Raman spectra from test samples and yielded for sepsis a sensitivity of 1.0 and specificity of 0.82. These results have been confirmed with an independent dataset (prediction accuracy 80%).

  9. Fast and accurate quantum molecular dynamics of dense plasmas across temperature regimes

    SciTech Connect

    Sjostrom, Travis; Daligault, Jerome

    2014-10-10

    Here, we develop and implement a new quantum molecular dynamics approximation that allows fast and accurate simulations of dense plasmas from cold to hot conditions. The method is based on a carefully designed orbital-free implementation of density functional theory. The results for hydrogen and aluminum are in very good agreement with Kohn-Sham (orbital-based) density functional theory and path integral Monte Carlo calculations for microscopic features such as the electron density as well as the equation of state. The present approach does not scale with temperature and hence extends to higher temperatures than is accessible in the Kohn-Sham method and lower temperatures than is accessible by path integral Monte Carlo calculations, while being significantly less computationally expensive than either of those two methods.

  10. Fast and accurate quantum molecular dynamics of dense plasmas across temperature regimes

    DOE PAGES

    Sjostrom, Travis; Daligault, Jerome

    2014-10-10

    Here, we develop and implement a new quantum molecular dynamics approximation that allows fast and accurate simulations of dense plasmas from cold to hot conditions. The method is based on a carefully designed orbital-free implementation of density functional theory. The results for hydrogen and aluminum are in very good agreement with Kohn-Sham (orbital-based) density functional theory and path integral Monte Carlo calculations for microscopic features such as the electron density as well as the equation of state. The present approach does not scale with temperature and hence extends to higher temperatures than is accessible in the Kohn-Sham method and lowermore » temperatures than is accessible by path integral Monte Carlo calculations, while being significantly less computationally expensive than either of those two methods.« less

  11. The Geometric Factor of Electrostatic Plasma Analyzers: A Case Study from the Fast Plasma Investigation for the Magnetospheric Multiscale mission

    NASA Technical Reports Server (NTRS)

    Collinson, Glyn A.; Dorelli, John Charles; Avanov, Leon A.; Lewis, Gethyn R.; Moore, Thomas E.; Pollock, Craig; Kataria, Dhiren O.; Bedington, Robert; Arridge, Chris S.; Chornay, Dennis J.; Gliese,Ulrik; Mariano, Al.; Barrie, Alexander C; Tucker, Corey; Owen, Christopher J.; Walsh, Andrew P.; Shappirio, Mark D.; Adrian, Mark L.

    2012-01-01

    We report our findings comparing the geometric factor (GF) as determined from simulations and laboratory measurements of the new Dual Electron Spectrometer (DES) being developed at NASA Goddard Space Flight Center as part of the Fast Plasma Investigation on NASA's Magnetospheric Multiscale mission. Particle simulations are increasingly playing an essential role in the design and calibration of electrostatic analyzers, facilitating the identification and mitigation of the many sources of systematic error present in laboratory calibration. While equations for laboratory measurement of the Geometric Factpr (GF) have been described in the literature, these are not directly applicable to simulation since the two are carried out under substantially different assumptions and conditions, making direct comparison very challenging. Starting from first principles, we derive generalized expressions for the determination of the GF in simulation and laboratory, and discuss how we have estimated errors in both cases. Finally, we apply these equations to the new DES instrument and show that the results agree within errors. Thus we show that the techniques presented here will produce consistent results between laboratory and simulation, and present the first description of the performance of the new DES instrument in the literature.

  12. Understanding ion cyclotron harmonic fast wave heating losses in the scrape off layer of tokamak plasmas

    SciTech Connect

    Bertelli, N; Jaeger, E F; Hosea, J C; Phillips, C K; Berry, L; Bonoli, P T; Gerhardt, S P; Green, D; LeBlanc, B; Perkins, R J; Ryan, P M; Taylor, G; Valeo, E J; Wilso, J R; Wright, J C

    2014-07-01

    Fast waves at harmonics of the ion cyclotron frequency, which have been used successfully on National Spherical Torus Experiment (NSTX), will also play an important role in ITER and are a promising candidate for the Fusion Nuclear Science Facility (FNSF) designs based on spherical torus (ST). Experimental studies of high harmonic fast waves (HHFW) heating on the NSTX have demonstrated that substantial HHFW power loss occurs along the open field lines in the scrape-off layer (SOL), but the mechanism behind the loss is not yet understood. The full wave RF code AORSA, in which the edge plasma beyond the last closed flux surface (LCFS) is included in the solution domain, is applied to specific NSTX discharges in order to predict the effects and possible causes of this power loss. In the studies discussed here, a collisional damping parameter has been implemented in AORSA as a proxy to represent the real, and most likely nonlinear, damping processes. A prediction for the NSTX Upgrade (NSTX-U) experiment, that will begin operation next year, is also presented, indicating a favorable condition for the experiment due to a wider evanescent region in edge density.*Research supported by the U.S. DOE under Contract No. DE-AC02-09CH11466 with Princeton University.

  13. Effect of the systemic inflammatory response, as provoked by elective orthopaedic surgery, on HbA1c.

    PubMed

    Chadburn, Andrew J; Garman, Elizabeth; Abbas, Raad; Modupe, Anu; Ford, Clare; Thomas, Osmond L; Chugh, Sanjiv; Deshpande, Shreeram; Gama, Rousseau

    2017-01-01

    Background In acutely ill patients with new onset hyperglycaemia, plasma glucose cannot reliably distinguish between stress hyperglycaemia and undiagnosed diabetes mellitus. We, therefore, investigated the diagnostic reliability of glycated haemoglobin (HbA1c) in acute illness by prospectively evaluating the effect of the systemic inflammatory response, as provoked by elective orthopaedic surgery, on HbA1c. Methods HbA1c and serum C-reactive protein concentrations were compared before and two days after elective knee or hip surgery in 30 patients without diabetes. C-reactive protein was used to assess the systemic inflammatory response. Results The mean (standard deviation) serum C-reactive protein increased following surgery (4.8 [7.5] vs. 179.7 [61.9] mg/L; P<0.0001). HbA1c was similar before and after surgery (39.2 [5.4] vs. 38.1 [5.1] mmol/moL, respectively; P = 0.4363). Conclusions HbA1c is unaffected within two days of a systemic inflammatory response as provoked by elective orthopaedic surgery. This suggests that HbA1c may be able to differentiate newly presenting type 2 diabetes mellitus from stress hyperglycaemia in acutely ill patients with new onset hyperglycaemia.

  14. Differential expression of cholesteryl ester transfer protein in the liver and plasma of fasted and fed transgenic mice.

    PubMed

    MacLean, P S; Vadlamudi, S; Hao, E; Barakat, H A

    2000-06-01

    Because cholesteryl ester transfer protein (CETP) is considered a potential target in the treatment of atherosclerosis, several reports have focused on the regulation of this enzyme, and there is evidence that insulin may be a regulatory factor. The present study examines the differential expression of the human CETP gene between physiologic conditions that are accompanied by low (fasted) and high (fed) insulin levels. CETP expression was examined in plasma and tissues of transgenic mice expressing the human CETP minigene after 12 hours of fasting (n = 20) or ad libitum feeding (n = 20) with normal mouse chow. Plasma cholesteryl ester transfer activity (CETA) was 20% higher in fed than in fasted mice, reflecting higher levels of CETP (P < 0.05). This observation was accompanied by higher liver mRNA in fed mice (100%, P < 0.05), as determined by ribonuclease protection assays, as well as by higher CETA (23%, P < 0.05) and CETP mass (29%, P < 0.05) in the particulate fraction of liver homogenates. These parameters of liver CETP expression correlated well with each other, as well as with plasma CETA. CETP in the liver particulate fraction was found as a doublet (approximately 70 and 65 kDa), which resolved to a single band (approximately 60 kDa) upon deglycosylation. No differences in CETP expression were observed in pooled adipose tissue samples from fed and fasted mice. Insulin and glucose were not related to any plasma or tissue parameter of CETP expression. In summary, the concerted, differential expression of CETP in the liver of fed and fasted transgenic mice appears to contribute to higher plasma CETP levels in fed mice, but the precise role of insulin and glucose in regulating CETP expression under fasted and fed conditions needs to be defined.

  15. Acute fasting in heifers as a model for assessing the relationship between plasma and follicular fluid NEFA concentrations.

    PubMed

    Jorritsma, R; de Groot, M W; Vos, P L A M; Kruip, T A M; Wensing, Th; Noordhuizen, J P T M

    2003-06-01

    It is known from epidemiological studies that negative energy balance in early lactating dairy cows is related to a depression in reproductive performance. Elevated plasma concentrations of non-esterified fatty acids (NEFA) are a typical metabolic characteristic of these animals and are proposed as the possible link. The suggestion is that NEFA might have a direct effect on the ovary, by affecting development of the oocyte or the granulosa cells. However, no data is available concerning the relationship between the concentration of NEFA in follicular fluid and plasma. Therefore, a cross-over study with 10 heifers around 15 months of age was conducted to analyze this relationship and examine the suggested effects of the negative energy balance on follicular growth. Investigation of these effects was performed on fasted heifers. The experimental treatment consisted of feeding hay with a subsequent period of fasting, to induce elevated plasma NEFA concentrations. Sampling of follicular fluid was performed using transvaginal aspiration of follicles, which were standardized using a synchronization protocol. In addition, concentrations of glucose, insulin, NEFA, and estradiol were measured in plasma. Follicular estradiol and progesterone concentrations were also measured to assess the quality of the dominant follicle. Fasting resulted in significantly lower plasma glucose (P=0.0006) and plasma insulin (P<0.0001) concentrations, higher plasma estradiol (P=0.008) and higher NEFA (P<0.001) concentrations, and smaller follicles (P=0.04) with lower estradiol:progesterone (E/P) ratios (P=0.05). Concentrations of NEFA in follicular fluid and plasma were closely related. Given this close relationship, we concluded that the presence of high plasma NEFA concentrations might link energy metabolism in early lactation with fertility.

  16. Device and method for relativistic electron beam heating of a high-density plasma to drive fast liners

    DOEpatents

    Thode, Lester E.

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner which is generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner.

  17. Plasma Dynamics and VUV Emission in a Fast Hollow Cathode Capillary Discharge

    NASA Astrophysics Data System (ADS)

    Soto, Leopoldo; Esaulov, Andrey; Silva, Patricio; Sylvester, Gustavo; Moreno, José; Zambra, Marcelo; Nazarenko, Andrey

    2000-10-01

    Following the world tendency to study the physical mechanisms to obtain laser emission in the VUV to soft X-ray region in table-top device, a fast capillary discharge has been constructed at Comisión Chilena de Energía Nuclear, CCHEN. The device is identical to designed by P. Choi and M. Favre, included an electron beam from the hollow cathode region to provide ionization on the axis (1). The discharge operates in Argon with a cathode pressure of 100-500 mtorr. The system works with differential vacuum, thus the anode pressure is around five times less than the cathode pressure. The radius of capillary is 0.4 mm and the length is 2.5 cm. For an applied voltage of 10 kV a peak current of 5 kA with a rise time of 4.8 ns is obtained (10^12 A/s). MHD simulations in order to study the plasma dynamics an temperature evolution were performed (2). A final radius of 100-200 microns is expected at 8 ns, 2 ns after the peak current with a electron density of 2 x 10^18 cm-3. An electron and ion temperature of 80 and 40 eV respectively are predicted. In addition to usual electrical diagnostics, time-space resolution pinhole images (multipinhole camera with a multichannel plate, four frames, one frame every 4 ns) and time resolved spectra in the region of 10 to 100 nm were performed. Dynamics of plasma compresion was studied from time resolved pinhole images. Detected spectra show that plasma consists of argon ions with ionization potential from ArVI to ArX. This work has been funded by FONDECYT grant 1980187 and a Presidential Chair in Science granted by Chilean government. Authors are thankful to K. Koshelev and P. Antsiferov (ISAN, Troitsk) for fruitful discussions and comments. 1.- P. Choi and M. Favre, Rev. Sci. Instrum. 69, 3118, (1998) 2.- A. Esaulov, P. Sasorov, L. Soto, M. Zambra and J. Sakai, ``Fast Hollow Cathode Capillary Discharge. MHD Simulation''. Submitted for publication.

  18. Development of a radio-frequency ion beam source for fast-ion studies on the large plasma device.

    PubMed

    Tripathi, S K P; Pribyl, P; Gekelman, W

    2011-09-01

    A helium ion beam source (23 kV/2.0 A) has been constructed for studying fast-ion physics in the cylindrical magnetized plasma of the large plasma device (LAPD). An inductive RF source produces a 10(19) m(-3) density plasma in a ceramic dome. A multi-aperture, rectangular (8 cm × 8 cm) three-grid system extracts the ion beam from the RF plasma. The ion beam is injected at a variety of pitch angles with Alfvénic speeds in the LAPD. The beam current is intense enough to excite magnetic perturbations in the ambient plasma. Measurements of the ion beam profile were made to achieve an optimum beam performance and a reliable source operation was demonstrated on the LAPD.

  19. Abnormal expression and function of Dectin-1 receptor in type 2 diabetes mellitus patients with poor glycemic control (HbA1c>8%).

    PubMed

    Cortez-Espinosa, Nancy; García-Hernández, Mariana H; Reynaga-Hernández, Elizabeth; Cortés-García, J Diego; Corral-Fernández, Nancy E; Rodríguez-Rivera, J Guillermo; Bravo-Ramírez, Anamaría; González-Amaro, Roberto; Portales-Pérez, Diana P

    2012-11-01

    Dectin-1 is a key innate receptor involved in various cellular responses and may have a direct role in chronic inflammatory conditions such as type 2 diabetes mellitus. The aim of this work was to evaluate the expression and function of Dectin-1 in peripheral blood mononuclear cells from T2D patients. Dectin-1 expression was analyzed by flow cytometry and RT-PCR in monocytes and lymphocyte subpopulations from T2D patients (n=34) and healthy subjects (n=29). Functional assays were used to assess cytokine synthesis, ROS levels and oxidative stress ratio. We found increased expression (MFI) of Dectin-1 in monocytes from T2D patients. Significantly higher Dectin-1 expression was also detected in CD4(+) T, CD8(+) T, B cells and NK cells from T2D patients compared to controls. In contrast, monocytes from T2D patients with poor glycemic control (HbA1c>8%) showed a diminished percentage of Dectin-1(+)/TLR2(+) cells. Negative correlations between the percent of Dectin-1(+)/TLR2(+) cells and fasting plasma glucose levels (FPG) and HbA1c levels were found. A significant reduction in basal levels of IL-10 was observed in patients with poor glycemic control (HbA1c>8%) compared to patients with appropriate glycemic control (HbA1c≤6.5%) and healthy controls, an effect that was not observed in monocytes stimulated with zymosan. Higher ROS levels in zymosan-stimulated cells from patients with poor glycemic control positively correlated with FPG levels, and the oxidative stress ratio was higher in T2D cells compared with controls. Our data indicate that Dectin-1 may be involved in the abnormal immune responses that are observed in patients with T2D.

  20. Mitochondrial DNA copy number augments performance of A1C and oral glucose tolerance testing in the prediction of type 2 diabetes

    PubMed Central

    Cho, Seong Beom; Koh, InSong; Nam, Hye-Young; Jeon, Jae-Pil; Lee, Hong Kyu; Han, Bok-Ghee

    2017-01-01

    Here, we tested the performance of the mitochondrial DNA copy number (mtDNA-CN) in predicting future type 2 diabetes (n = 1108). We used the baseline clinical data (age, sex, body mass index, waist-to-hip ratio, systolic and diastolic blood pressure) and the mtDNA-CN, hemoglobin A1c (A1C) levels and results of oral glucose tolerance test (OGTT) including fasting plasma glucose, 1-hour glucose, and 2-hour glucose levels, to predict future diabetes. We built a prediction model using the baseline data and the diabetes status at biannual follow-up of 8 years. The mean area under curve (AUC) for all follow-ups of the full model including all variables was 0.92 ± 0.04 (mean ± standard deviation), while that of the model excluding the mtDNA-CN was 0.90 ± 0.03. The sensitivity of the f4ull model was much greater than that of the model not including mtDNA-CN: the mean sensitivities of the model with and without mtDNA-CN were 0.60 ± 0.06 and 0.53 ± 0.04, respectively. We found that the mtDNA-CN of peripheral leukocytes is a biomarker that augments the predictive power for future diabetes of A1C and OGTT. We believe that these results could provide invaluable information for developing strategies for the management of diabetes. PMID:28251996

  1. Determination of collision rates relevant to Weibel-like instability growth rates in classical and non-classical plasmas encountered in fast-ignition experiments

    SciTech Connect

    Hill, J M; Key, M H

    2004-10-18

    Analytical simulations of fast-electron currents induced by high-density laser-plasma interactions require estimation of various plasma and beam parameters, including temperatures, densities, and collision rates. This note describes a technique used to estimate or calculate these parameters for the case of contemporary multi-terawatt experiments using foil targets as well as for anticipated fast-ignition-scale experiments.

  2. Effects of the fast plasma sheet flow on the geosynchronous magnetic configuration: Geotail and GOES coordinated study

    NASA Astrophysics Data System (ADS)

    Ohtani, S.; Singer, H. J.; Mukai, T.

    2006-01-01

    The present study statistically examines how (or if) the geosynchronous (GOES) magnetic field responds to fast earthward flow observed by the Geotail satellite in the plasma sheet. The change of the GOES H (north-south) component within 15 min of the detection of fast flows, ΔH, is used as a primary measure of the geosynchronous response. It is found that following the detection of fast flows, the geosynchronous magnetic field rarely dipolarizes, but it often becomes more stretched, which is manifested by negative ΔH. This H decrease is not accompanied by any correlated variation of the D (azimuthal) component, suggesting that the associated stretching is not an edge effect of the substorm current wedge formation, but it can be attributed to the intensification of the local tail current. No systematic dependence of ΔH on the satellite separation can be found. On the other hand, the geosynchronous magnetic field tends to dipolarize if it is already stretched significantly, although the associated changes in the H and V (radial) components are not much larger than those in events that are not preconditioned. The flow intensity does not seem to be a controlling factor, either. However, caution needs to be exercised because the present study is not able to address the azimuthal structure of the fast flow. It is concluded that in most events the fast plasma flow does not reach geosynchronous orbit and that the generation of the fast plasma flow in the plasma sheet is not sufficient for causing geosynchronous dipolarization.

  3. Hemoglobin A1C above threshold levels are associated with decreased β-cell function in overweight Latino youth

    PubMed Central

    Toledo-Corral, Claudia M.; Vargas, Lisa G.; Goran, Michael I.; Weigensberg, Marc J.

    2011-01-01

    Objective To determine, in an overweight pediatric population, if an A1C-determined high risk, pre-diabetic state (A1C ≥6.0–6.4%) is associated with decreased insulin sensitivity and β-cell dysfunction, known factors in the pathogenesis of type 2 diabetes. Study design We divided 206 healthy overweight Latino adolescents (124 male/82 female; age 13.1±2.0 yrs), into 2 groups: Lower Risk (LR, n=179) had A1C <6.0%; and High Risk (HR, n=27) had A1C 6.0–6.4%. Measures included A1C; OGTT fasting & 2-hr glucose and insulin; insulin sensitivity (SI), acute insulin response (AIR), and disposition index (DI, an index of β-cell function) by frequently sampled FSIVGTT with minimal modeling. Body fat was determined by DEXA. Results Compared with the LR group, the HR group had 21% lower SI (1.21±0.06 vs. 1.54±0.13, p<0.05), 30% lower AIR (928±102 vs. 1342±56, p<0.01), and 31% lower DI (1390±146 vs. 2023±83, p=0.001) after adjusting for age and total percent body fat. Conclusion These data provide clear evidence of greater impairment of β-cell function in those overweight Latino children with A1C 6.0–6.4%, and would thereby support the adoption of the International Expert Committee A1C-determined definition of high risk state for overweight children at risk for type 2 diabetes. PMID:22137671

  4. The Prevalence and Associated Factors of Periodontitis According to Fasting Plasma Glucose in the Korean Adults

    PubMed Central

    Hong, Jae Won; Noh, Jung Hyun; Kim, Dong-Jun

    2016-01-01

    Abstract Although the relationship between diabetes and periodontitis is well established, the association between periodontitis and prediabetes has been investigated less extensively. Furthermore, there has been little research on the prevalence of periodontitis among individuals with prediabetes and diabetes as well as in the overall population using nationally representative data. Among 12,406 adults (≥19 years’ old) who participated in the 2012–2013 Korea National Health and Nutrition Examination Survey, a total of 9977 subjects completed oral and laboratory examinations and were included in this analysis. Periodontitis was defined as a community periodontal index score of ≥3 according to the World Health Organization criteria. The fasting plasma glucose level was categorized into the following 5 groups: normal fasting glucose (NFG) 1 (<90 mg/dL), NFG 2 (90–99 mg/dL), impaired fasting glucose (IFG) 1 (100–110 mg/dL), IFG 2 (111–125 mg/dL), and diabetes (≥126 mg/dL). Overall, the weighted prevalence of periodontitis among the Korean adult population was 24.8% (23.3–26.4%) (weight n = 8,455,952/34,086,014). The unadjusted weighted prevalences of periodontitis were 16.7%, 22.8%, 29.6%, 40.7%, and 46.7% in the NFG 1, NFG 2, IFG 1, IFG 2, and diabetes groups, respectively (P < 0.001). After adjusting for age, sex, smoking history, heavy alcohol drinking, college graduation, household income, waist circumference, serum triglyceride level, serum high-density lipoprotein cholesterol level, and the presence of hypertension, the adjusted weighted prevalence of periodontitis increased to 29.7% in the IFG 2 group (P = 0.045) and 32.5% in the diabetes group (P < 0.001), compared with the NFG 1 group (24%). The odds ratios for periodontitis with the above-mentioned variables as covariates were 1.42 (95% confidence interval [CI] 1.14–1.77, P = 0.002) in the diabetes group and 1.33 (95% CI 1.01–1.75, P = 0.044) in the IFG

  5. Impact of glutathione-HbA1c on HbA1c measurement in diabetes diagnosis via array isoelectric focusing, liquid chromatography, mass spectrometry and ELISA.

    PubMed

    Li, Si; Guo, Chen-Gang; Chen, Lu; Yin, Xiao-Yang; Wu, Yi-Xin; Fan, Liu-Yin; Fan, Hui-Zhi; Cao, Cheng-Xi

    2013-10-15

    Hemoglobin A1c (HbA1c) has been proven to be a key biomarker for diabetes screening, and glutathiolation of HbA1c (viz., GSS-HbA1c) has been identified. However, the impact of GSS-HbA1c on the measurement of HbA1c for diabetes screening has not been quantitatively assessed yet. To address the issue, the micropreparative capillary isoelectric focusing (cIEF) developed in our previous work was used for the high resolution separation and purification of hemoglobin (Hb) species. The main fractions of HbA0, HbA3 and HbA1c extracted from the developed cIEF were identified by validated Mono S method. The proposed GSS-HbA1c fractions in the cIEF were pooled and identified by electrospray ionization mass spectrometry (ESI-MS). The HbA1c enzyme-linked immunosorbent assay (ELISA) kit was employed for further quantitative analysis of GSS-HbA1c. A total of 34 blood samples with HbA1c levels from 4.2% to 13.4% were assessed via the above comprehensive strategy of IEF-HPLC-MS-ELISA. It was demonstrated that the HbA1c levels detected by cation exchange LC were considerably influenced by the glutathiolation of Hb and the range of detected GSS-HbA1c values was between 0.23% and 0.74%. The results and developed cIEF methods have considerable significances for investigation of diabetes and clinical diagnosis.

  6. Efficiency of fast wave current drive for a weakly relativistic plasma

    SciTech Connect

    Chiu, S.C.; Lin-Liu, Y.R. ); Karney, C.F.F. . Plasma Physics Lab.)

    1993-04-01

    Current drive by fast waves (FWCD) is an important candidate for steady-state operation of tokamaks. Major experiments using this scheme are being carried out on DIII-D. There has been considerable study of the theoretical efficiency of FWCD. In Refs. 4 and 5, the nonrelativistic efficiency of FWCD at arbitrary frequencies was studied. For DIII-D parameters, the results can be considerably different from the Landau and Alfven limits. At the high temperatures of reactors and DIII-D upgrade, relativistic effects become important. In this paper, the relativistic FWCD efficiency for arbitrary frequencies is studied. Assuming that the plasma is weakly relativistic, i.e., T[sub e]/Mc[sup 2] is small, an analytic expression for FWCD is obtained for high resonant energies (U[sub ph]/u[sub Te][much gt]). Comparisons with the results from a numerical code ADJ and the nonrelativistic results shall be made and analytical fits in the whole range of velocities shall be presented.

  7. Efficiency of fast wave current drive for a weakly relativistic plasma

    SciTech Connect

    Chiu, S.C.; Lin-Liu, Y.R.; Karney, C.F.F.

    1993-04-01

    Current drive by fast waves (FWCD) is an important candidate for steady-state operation of tokamaks. Major experiments using this scheme are being carried out on DIII-D. There has been considerable study of the theoretical efficiency of FWCD. In Refs. 4 and 5, the nonrelativistic efficiency of FWCD at arbitrary frequencies was studied. For DIII-D parameters, the results can be considerably different from the Landau and Alfven limits. At the high temperatures of reactors and DIII-D upgrade, relativistic effects become important. In this paper, the relativistic FWCD efficiency for arbitrary frequencies is studied. Assuming that the plasma is weakly relativistic, i.e., T{sub e}/Mc{sup 2} is small, an analytic expression for FWCD is obtained for high resonant energies (U{sub ph}/u{sub Te}{much_gt}). Comparisons with the results from a numerical code ADJ and the nonrelativistic results shall be made and analytical fits in the whole range of velocities shall be presented.

  8. Xanthochromia of the skull bone associated with HbA1c.

    PubMed

    Schäfer, T; Klintschar, M; Lichtinghagen, R; Plagemann, I; Smith, A; Budde, E; Hagemeier, L

    2016-03-01

    The color of the surface of 105 skull bones (part of the parietal bone) was determined using a portable spectral colorimeter (spectro color(®)). By this means it was possible to characterize the color objectively according to the L*a*b* color system defined by the "International Commission de l'Eclairage" (CIE). Biochemical markers of carbohydrate metabolism, HbA1c from venous blood, and glucose/lactate concentrations from vitreous humor, were also determined, for assessment of the ante-mortem plasma glucose concentration using Traub's sum formula. As biochemical markers for lipid metabolism disorder, cholesterol, triglycerides, high density lipoprotein (HDL), low density lipoprotein (LDL) and very low density lipoprotein (VLDL) were all determined from venous blood. There is a significant correlation of bone yellowing with HbA1c (p<0.001) and age (p<0.001). The literature asserts a significant correlation between diabetic condition and yellowing of the skull bone. Despite efforts to find the substance responsible for the yellowing of the bone in chronic metabolism disorder, no significant correlation was found between bone color and lipoproteins/bone extracted lipid acids.

  9. Consumption of wheat aleurone-rich foods increases fasting plasma betaine and modestly decreases fasting homocysteine and LDL-cholesterol in adults.

    PubMed

    Price, Ruth K; Keaveney, Edel M; Hamill, Lesley L; Wallace, Julie M W; Ward, Mary; Ueland, Per M; McNulty, Helene; Strain, J J; Parker, Michael J; Welch, Robert W

    2010-12-01

    There is strong evidence that whole-grain foods protect against heart disease. Although underlying mechanisms and components are unclear, betaine, found at high levels in wheat aleurone, may play a role. We evaluated the effects of a diet high in wheat aleurone on plasma betaine and related measures. In a parallel, single-blinded intervention study, 79 healthy participants (aged 45-65 y, BMI ≥ 25 kg/m(2)) incorporated either aleurone-rich cereal products (27 g/d aleurone) or control products balanced for fiber and macronutrients into their habitual diets for 4 wk. Fasting blood samples were taken at baseline and postintervention (4 wk) from participants. Compared with the control, the aleurone products provided an additional 279 mg/d betaine and resulted in higher plasma betaine (P < 0.001; intervention effect size: 5.2 μmol/L) and lower plasma total homocysteine (tHcy) (P = 0.010; -0.7 μmol/L). Plasma dimethylglycine and methionine, which are products of betaine-mediated homocysteine remethylation, were also higher (P < 0.001; P = 0.027) relative to control. There were no significant effects on plasma choline or B vitamins (folate, riboflavin, and vitamin B-6). However, LDL cholesterol was lower than in the control group (P = 0.037). We conclude that incorporating aleurone-rich products into the habitual diet for 4 wk significantly increases plasma betaine concentrations and lowers tHcy, which is attributable to enhanced betaine-homocysteine methyltransferase-mediated remethylation of homocysteine. Although this supports a role for betaine in the protective effects of whole grains, concomitant decreases in LDL suggest more than one component or mechanism may be responsible.

  10. Generation of Non-Inductive H-Mode Plasmas with 30 MHz Fast Wave Heating in NSTX-U

    NASA Astrophysics Data System (ADS)

    Taylor, G.; Bertelli, N.; Gerhardt, S. P.; Hosea, J. C.; Mueller, D.; Perkins, R. J.; Poli, F. M.; Wilson, J. R.; Raman, R.

    2016-10-01

    A Fusion Nuclear Science Facility based on a spherical tokamak must generate the plasma current (Ip) with little or no central solenoid field. The NSTX-U non-inductive (NI) plasma research program is addressing this goal by developing NI start-up, ramp-up and sustainment scenarios separately. 4 MW of 30 MHz fast wave power is predicted to ramp Ip to 400 kA, a level sufficient to avoid significant shine-through of 90 keV ions from neutral beam injection. In 2010, experiments in NSTX demonstrated that 1.4 MW of 30 MHz high-harmonic fast wave (HHFW) power could generate an Ip = 300 kA H-mode discharge with a NI Ip fraction, fNI, around 0.7 at the maximum axial toroidal field (BT(0)) in NSTX of 0.55 T. NSTX-U is a major upgrade of NSTX that will eventually allow the generation of plasmas with BT(0) up to 1 T. Full wave simulations of 30 MHz HHFW heating in NSTX-U predict reduced FW power loss in the plasma edge as BT(0) is increased. HHFW experiments this year aim to couple 3 - 4 MW of 30 MHz HHFW power into an Ip = 250 - 350 kA plasma with BT(0) up to 0.75 T to generate a fNI = 1 H-mode plasma. These experiments should benefit from the improved fast wave coupling predicted at higher BT(0) in NSTX-U. Work supported by USDOE Contract No. DE-AC02-09CH11466.

  11. Large-amplitude hydromagnetic waves in collisionless relativistic plasma - Exact solution for the fast-mode magnetoacoustic wave

    NASA Technical Reports Server (NTRS)

    Barnes, A.

    1983-01-01

    An exact nonlinear solution is found to the relativistic kinetic and electrodynamic equations (in their hydromagnetic limit) that describes the large-amplitude fast-mode magnetoacoustic wave propagating normal to the magnetic field in a collisionless, previously uniform plasma. It is pointed out that a wave of this kind will be generated by transverse compression of any collisionless plasma. The solution is in essence independent of the detailed form of the particle momentum distribution functions. The solution is obtained, in part, through the method of characteristics; the wave exhibits the familiar properties of steepening and shock formation. A detailed analysis is given of the ultrarelativistic limit of this wave.

  12. A study assessing the association of glycated hemoglobin A1C (HbA1C) associated variants with HbA1C, chronic kidney disease and diabetic retinopathy in populations of Asian ancestry.

    PubMed

    Chen, Peng; Ong, Rick Twee-Hee; Tay, Wan-Ting; Sim, Xueling; Ali, Mohammad; Xu, Haiyan; Suo, Chen; Liu, Jianjun; Chia, Kee-Seng; Vithana, Eranga; Young, Terri L; Aung, Tin; Lim, Wei-Yen; Khor, Chiea-Chuen; Cheng, Ching-Yu; Wong, Tien-Yin; Teo, Yik-Ying; Tai, E-Shyong

    2013-01-01

    Glycated hemoglobin A1C (HbA1C) level is used as a diagnostic marker for diabetes mellitus and a predictor of diabetes associated complications. Genome-wide association studies have identified genetic variants associated with HbA1C level. Most of these studies have been conducted in populations of European ancestry. Here we report the findings from a meta-analysis of genome-wide association studies of HbA1C levels in 6,682 non-diabetic subjects of Chinese, Malay and South Asian ancestries. We also sought to examine the associations between HbA1C associated SNPs and microvascular complications associated with diabetes mellitus, namely chronic kidney disease and retinopathy. A cluster of 6 SNPs on chromosome 17 showed an association with HbA1C which achieved genome-wide significance in the Malays but not in Chinese and Asian Indians. No other variants achieved genome-wide significance in the individual studies or in the meta-analysis. When we investigated the reproducibility of the findings that emerged from the European studies, six loci out of fifteen were found to be associated with HbA1C with effect sizes similar to those reported in the populations of European ancestry and P-value ≤ 0.05. No convincing associations with chronic kidney disease and retinopathy were identified in this study.

  13. Effect of low glycemic load diet on glycated hemoglobin (HbA1c) in poorly-controlled diabetes patients.

    PubMed

    Ziaee, Amir; Afaghi, Ahmad; Sarreshtehdari, Majied

    2011-12-29

    Different carbohydrate diets have been administrated to diabetic patients to evaluate the glycemic response, while Poor-controlled diabetes is increasing world wide. To investigate the role of an alternative carbohydrate diet on glycemic control, we explored the effect of a low glycemic load (Low GL)-high fat diet on glycemic response and also glycated hemoglobin (HbA1c) of poor-controlled diabetes patients. Hundred poorly-controlled diabetes patients, HbA1c > 8, age 52.8 ± 4.5 y, were administrated a low GL diet , GL = 67 (Energy 1800 kcal; total fat 36%; fat derived from olive oil and nuts 15%; carbohydrate 42%; protein 22%) for 10 weeks. Patients did their routine life style program during intervention. Fasting blood glucose and HbA1c before and after intervention with significant reduction were: 169 ± 17, 141 ± 12; 8.85% (73 mmol/mol) ± 0.22%, and 7.81% (62 mmol/mol) ± 0.27%; respectively (P < 0.001). Mean fasting blood glucose reduced by 28.1 ± 12.5 and HbA1c by 1.1% (11 mmol/mol) ± 0.3% (P=0.001). There was positive moderate correlation between HbA1c concentration before intervention and FBS reduction after intervention (P < 0.001, at 0.01 level, R =0.52), and strong positive correlation between FBS before intervention and FBS reduction (P < 0.001, at 0.01 level, R = 0.70). This study demonstrated that our alternative low glycemic load diet can be effective in glycemic control.

  14. DPP-4 inhibitor treatment: β-cell response but not HbA1c reduction is dependent on the duration of diabetes

    PubMed Central

    Kozlovski, Plamen; Bhosekar, Vaishali; Foley, James E

    2017-01-01

    Introduction Dipeptidyl peptidase-4 (DPP-4) inhibitors reduce hyperglycemia in patients with type 2 diabetes mellitus (T2DM) by enhancing insulin and suppressing glucagon secretion. Since T2DM is associated with progressive loss of β-cell function, we hypothesized that the DPP-4 inhibitor action to improve β-cell function would be attenuated with longer duration of T2DM. Methods Data from six randomized, placebo-controlled trials of 24 weeks duration, where β-cell response to vildagliptin 50 mg twice daily was assessed, were pooled. In each study, the insulin secretory rate relative to glucose (ISR/G 0–2h) during glucose load (standard meal or oral glucose tolerance test) was assessed at baseline and end of study. The mean placebo-subtracted difference (PSD) in the change in ISR/G 0–2h from baseline for each study was evaluated as a function of age, duration of T2DM, baseline ISR/G 0–2h, glycated hemoglobin (HbA1c), fasting plasma glucose, body mass index, and mean PSD in the change in HbA1c from baseline, using univariate model. Results There was a strong negative association between the PSD in the change from baseline in ISR/G 0–2h and duration of T2DM (r= −0.89, p<0.02). However, there was no association between the PSD in the change from baseline in ISR/G 0–2h and the PSD in the change from baseline in HbA1c (r=0.33, p=0.52). None of the other characteristics were significantly associated with mean PSD change in ISR/G 0–2h. Conclusion These findings indicate that the response of the β-cell, but not the HbA1c reduction, with vildagliptin is dependent on duration of T2DM. Further, it can be speculated that glucagon suppression may become the predominant mechanism via which glycemic control is improved when treatment with a DPP-4 inhibitor, such as vildagliptin, is initiated late in the natural course of T2DM.

  15. Performance of a Discrete Wavelet Transform for Compressing Plasma Count Data and its Application to the Fast Plasma Investigation on NASA's Magnetospheric Multiscale Mission

    NASA Technical Reports Server (NTRS)

    Barrie, Alexander C.; Yeh, Penshu; Dorelli, John C.; Clark, George B.; Paterson, William R.; Adrian, Mark L.; Holland, Matthew P.; Lobell, James V.; Simpson, David G.; Pollock, Craig J.; Moore, Thomas E.

    2015-01-01

    Plasma measurements in space are becoming increasingly faster, higher resolution, and distributed over multiple instruments. As raw data generation rates can exceed available data transfer bandwidth, data compression is becoming a critical design component. Data compression has been a staple of imaging instruments for years, but only recently have plasma measurement designers become interested in high performance data compression. Missions will often use a simple lossless compression technique yielding compression ratios of approximately 2:1, however future missions may require compression ratios upwards of 10:1. This study aims to explore how a Discrete Wavelet Transform combined with a Bit Plane Encoder (DWT/BPE), implemented via a CCSDS standard, can be used effectively to compress count information common to plasma measurements to high compression ratios while maintaining little or no compression error. The compression ASIC used for the Fast Plasma Investigation (FPI) on board the Magnetospheric Multiscale mission (MMS) is used for this study. Plasma count data from multiple sources is examined: resampled data from previous missions, randomly generated data from distribution functions, and simulations of expected regimes. These are run through the compression routines with various parameters to yield the greatest possible compression ratio while maintaining little or no error, the latter indicates that fully lossless compression is obtained. Finally, recommendations are made for future missions as to what can be achieved when compressing plasma count data and how best to do so.

  16. A global study of the unmet need for glycemic control and predictor factors among patients with type 2 diabetes mellitus who have achieved optimal fasting plasma glucose control on basal insulin

    PubMed Central

    Chou, Engels; Colagiuri, Stephen; Gaàl, Zsolt; Lavalle, Fernando; Mkrtumyan, Ashot; Nikonova, Elena; Tentolouris, Nikolaos; Vidal, Josep; Davies, Melanie

    2016-01-01

    Abstract Background This study used data from different sources to identify the extent of the unmet need for postprandial glycemic control in patients with type 2 diabetes mellitus (T2DM) after the initiation of basal insulin therapy in Europe, Asia Pacific, the United States, and Latin America. Methods Different levels of evidence were used as available for each country/region, with data extracted from seven randomized controlled trials (RCTs), three clinical trial registries (CTRs), and three electronic medical record (EMR) databases. Glycemic status was categorized as “well controlled” (glycated hemoglobin [HbA1c] at target [<7%]), “residual hyperglycemia” (fasting plasma glucose [FPG] but not HbA1c at target [FPG <7.2/7.8 mmol/L, <130/140 mg/dL, depending on country‐specific recommendations]), or “uncontrolled” (both FPG and HbA1c above target). Predictor factors were identified from the RCT data set using logistic regression analysis. Results RCT data showed that 16.9% to 28.0%, 42.7% to 54.4%, and 16.9% to 38.1% of patients with T2DM had well‐controlled glycemia, residual hyperglycemia, and uncontrolled hyperglycemia, respectively. In CTRs, respective ranges were 21.8% to 33.6%, 31.5% to 35.6%, and 30.7% to 46.8%, and in EMR databases were 4.4% to 21.0%, 23.9% to 31.8%, and 53.6% to 63.8%. Significant predictor factors of residual hyperglycemia identified from RCT data included high baseline HbA1c (all countries/regions except Brazil), high baseline FPG (United Kingdom/Japan), longer duration of diabetes (Brazil), and female sex (Europe/Latin America). Conclusions Irrespective of intrinsic differences between data sources, 24% to 54% of patients with T2DM globally had residual hyperglycemia with HbA1c not at target, despite achieving FPG control, indicating a significant unmet need for postprandial glycemic control. PMID:27606888

  17. Alfvén eigenmode stability and fast ion loss in DIII-D and ITER reversed magnetic shear plasmas

    NASA Astrophysics Data System (ADS)

    Van Zeeland, M. A.; Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; Spong, D. A.; Austin, M. E.; Fisher, R. K.; García Muñoz, M.; Gorelenkova, M.; Luhmann, N.; Murakami, M.; Nazikian, R.; Pace, D. C.; Park, J. M.; Tobias, B. J.; White, R. B.

    2012-09-01

    Neutral beam injection into reversed-magnetic shear DIII-D plasmas produces a variety of Alfvénic activity including toroidicity-induced Alfvén eigenmodes (TAEs) and reversed shear Alfvén eigenmodes (RSAEs). With measured equilibrium profiles as inputs, the ideal MHD code NOVA is used to calculate eigenmodes of these plasmas. The postprocessor code NOVA-K is then used to perturbatively calculate the actual stability of the modes, including finite orbit width and finite Larmor radius effects, and reasonable agreement with the spectrum of observed modes is found. Using experimentally measured mode amplitudes, fast ion orbit following simulations have been carried out in the presence of the NOVA calculated eigenmodes and are found to reproduce the dominant energy, pitch and temporal evolution of the losses measured using a large bandwidth scintillator diagnostic. The same analysis techniques applied to a DT 8 MA ITER steady-state plasma scenario with reversed-magnetic shear and both beam ion and alpha populations show Alfvén eigenmode instability. Both RSAEs and TAEs are found to be unstable with maximum growth rates occurring for toroidal mode number n = 6 and the majority of the drive coming from fast ions injected by the 1 MeV negative ion beams. AE instability due to beam ion drive is confirmed by the non-perturbative code TAEFL. Initial fast ion orbit following simulations using the unstable modes with a range of amplitudes (δB/B = 10-5-10-3) have been carried out and show negligible fast ion loss. The lack of fast ion loss is a result of loss boundaries being limited to large radii and significantly removed from the actual modes themselves.

  18. The Long and Winding Road to Optimal HbA1c Measurement

    PubMed Central

    Little, Randie R.; Rohlfing, Curt

    2016-01-01

    The importance of hemoglobin A1c (HbA1c) as an indicator of mean glycemia and risks for complications in patients with diabetes mellitus was established by the results of long-term clinical trials, most notably the Diabetes Control and Complications Trial (DCCT) and United Kingdom Prospective Diabetes Study (UKPDS), published in 1993 and 1998 respectively. However, clinical application of recommended HbA1c targets that were based on these studies was difficult due to lack of comparability of HbA1c results among assay methods and laboratories. Thus, the National Glycohemoglobin Standardization Program (NGSP) was initiated in 1996 with the goal of standardizing HbA1c results to those of the DCCT/UKPDS. HbA1c standardization efforts have been highly successful; however, a number of issues have emerged on the “long and winding road” to better HbA1c, including the development of a higher-order HbA1c reference method by the International Federation of Clinical Chemistry (IFCC), recommendations to use HbA1c to diagnose as well as monitor diabetes, and point-of-care (POC) HbA1c testing. Here, we review the past, present and future of HbA1c standardization and describe the current status of HbA1c testing, including limitations that healthcare providers need to be aware of when interpreting HbA1c results. PMID:23318564

  19. Fast Plasma Shutdowns Obtained With Massive Hydrogenic, Noble and Mixed-Gas Injection in DIII-D

    SciTech Connect

    Wesley, J; Hollmann, E; Jernigan, T; Van Zeeland, M; Baylor, L; Boedo, J; Combs, S; Evans, T; Groth, M; Humphreys, D; Hyatt, A; Izzo, V; James, A; Moyer, R; Parks, P; Rudakov, D; Strait, E; Wu, W; Yu, J

    2008-10-14

    Massive gas injection (MGI) experiments with H{sub 2}, D{sub 2}, He, Ne and Ar and 'mixed' (H{sub 2} + Ar and D{sub 2} + Ne) gases injected into 'ITER-similar' 1.3-MA H-mode plasmas are described. Gas species, injected quantity Q, delivery time, t{sub inj}, rate-of-rise and intrinsic and added impurities are found to affect the attributes and 'disruption mitigation' efficacies of the resulting fast plasma shutdowns. With sufficient Q and t{sub inj} < {approx}2 ms, all species provide fast (within {le} {approx}3 ms), more-or-less uniform radiative dissipation of the 0.7-MJ plasma thermal energy and fast but benign current decays with reduced vacuum vessel vertical force impulse. With pure and mixed low-Z gases, free-electron densities up to 2 x 10{sup 21} m{sup -3} are obtained. While these densities are high relative to normal tokamak densities, they are still an order of magnitude smaller than the densities required for unconditional mitigation of the runaway electron avalanche process. Key information relevant to the design of effective MGI systems for larger tokamaks and ITER has been obtained and the collective species and Q-variation data provides a rich basis for validation of emerging 2D + t MHD/transport/radiation models.

  20. Fasting and diet content affect stress-induced changes in plasma glucose and cortisol in Juvenile chinook salmon. [Oncorhynchus tshawytscha

    SciTech Connect

    Barton, B.A.; Schreck, C.B. ); Fowler, L.G. )

    1988-01-01

    Juvenile chinook salmon (Oncorhynchus tshawytscha) reared on low-, medium-, or high-lipid diets for 18 weeks were either kept on their respective diets or fasted for 20 d; then they were subjected to a 30-s handling stress or to handling plus continuous confinement. In fish that were handled but not confined, poststress hyperglycemia was greatest in fed fish that received the high-lipid diet and was generally lower in fasted than in fed fish. Plasma cortisol elevations in response to handling or handling plus confinement stress were not appreciably affected by diet type or fasting. The result indicated that prior feeding regimes and the types of diet fed should be considered when one is interpreting the magnitude of hyperglycemic stress responses in juvenile chinook salmon.

  1. In Flight Calibration of the Magnetospheric Multiscale Mission Fast Plasma Investigation

    NASA Technical Reports Server (NTRS)

    Barrie, Alexander C.; Gershman, Daniel J.; Gliese, Ulrik; Dorelli, John C.; Avanov, Levon A.; Rager, Amy C.; Schiff, Conrad; Pollock, Craig J.

    2015-01-01

    The Fast Plasma Investigation (FPI) on the Magnetospheric Multiscale mission (MMS) combines data from eight spectrometers, each with four deflection states, into a single map of the sky. Any systematic discontinuity, artifact, noise source, etc. present in this map may be incorrectly interpreted as legitimate data and incorrect conclusions reached. For this reason it is desirable to have all spectrometers return the same output for a given input, and for this output to be low in noise sources or other errors. While many missions use statistical analyses of data to calibrate instruments in flight, this process is insufficient with FPI for two reasons: 1. Only a small fraction of high resolution data is downloaded to the ground due to bandwidth limitations and 2: The data that is downloaded is, by definition, scientifically interesting and therefore not ideal for calibration. FPI uses a suite of new tools to calibrate in flight. A new method for detection system ground calibration has been developed involving sweeping the detection threshold to fully define the pulse height distribution. This method has now been extended for use in flight as a means to calibrate MCP voltage and threshold (together forming the operating point) of the Dual Electron Spectrometers (DES) and Dual Ion Spectrometers (DIS). A method of comparing higher energy data (which has low fractional voltage error) to lower energy data (which has a higher fractional voltage error) will be used to calibrate the high voltage outputs. Finally, a comparison of pitch angle distributions will be used to find remaining discrepancies among sensors.

  2. In Flight Calibration of the Magnetospheric Multiscale Mission Fast Plasma Investigation

    NASA Technical Reports Server (NTRS)

    Barrie, Alexander C.; Gershman, Daniel J.; Gliese, Ulrik; Dorelli, John C.; Avanov, Levon A.; Salo, Chad L.; Tucker, Corey J.; Holland, Mathew P.; Pollock, Craig J.

    2015-01-01

    The Fast Plasma Investigation (FPI) on the Magnetospheric Multiscale mission (MMS) combines data from eight spectrometers, each with four deflection states, into a single map of the sky. Any systematic discontinuity, artifact, noise source, etc. present in this map may be incorrectly interpreted as legitimate data and incorrect conclusions reached. For this reason it is desirable to have all spectrometers return the same output for a given input, and for this output to be low in noise sources or other errors. While many missions use statistical analyses of data to calibrate instruments in flight, this process is difficult with FPI for two reasons: 1. Only a small fraction of high resolution data is downloaded to the ground due to bandwidth limitations and 2: The data that is downloaded is, by definition, scientifically interesting and therefore not ideal for calibration. FPI uses a suite of new tools to calibrate in flight. A new method for detection system ground calibration has been developed involving sweeping the detection threshold to fully define the pulse height distribution. This method has now been extended for use in flight as a means to calibrate MCP voltage and threshold (together forming the operating point) of the Dual Electron Spectrometers (DES) and Dual Ion Spectrometers (DIS). A method of comparing higher energy data (which has low fractional voltage error) to lower energy data (which has a higher fractional voltage error) will be used to calibrate the high voltage outputs. Finally, a comparison of pitch angle distributions will be used to find remaining discrepancies among sensors.

  3. FAST MAGNETIC FIELD AMPLIFICATION IN THE EARLY UNIVERSE: GROWTH OF COLLISIONLESS PLASMA INSTABILITIES IN TURBULENT MEDIA

    SciTech Connect

    Falceta-Gonçalves, D.; Kowal, G.

    2015-07-20

    In this work we report on a numerical study of the cosmic magnetic field amplification due to collisionless plasma instabilities. The collisionless magnetohydrodynamic equations derived account for the pressure anisotropy that leads, in specific conditions, to the firehose and mirror instabilities. We study the time evolution of seed fields in turbulence under the influence of such instabilities. An approximate analytical time evolution of the magnetic field is provided. The numerical simulations and the analytical predictions are compared. We found that (i) amplification of the magnetic field was efficient in firehose-unstable turbulent regimes, but not in the mirror-unstable models; (ii) the growth rate of the magnetic energy density is much faster than the turbulent dynamo; and (iii) the efficient amplification occurs at small scales. The analytical prediction for the correlation between the growth timescales and pressure anisotropy is confirmed by the numerical simulations. These results reinforce the idea that pressure anisotropies—driven naturally in a turbulent collisionless medium, e.g., the intergalactic medium, could efficiently amplify the magnetic field in the early universe (post-recombination era), previous to the collapse of the first large-scale gravitational structures. This mechanism, though fast for the small-scale fields (∼kpc scales), is unable to provide relatively strong magnetic fields at large scales. Other mechanisms that were not accounted for here (e.g., collisional turbulence once instabilities are quenched, velocity shear, or gravitationally induced inflows of gas into galaxies and clusters) could operate afterward to build up large-scale coherent field structures in the long time evolution.

  4. Heat flux of fast electrons to the limiter in lower hybrid current drive plasma on WT-3

    NASA Astrophysics Data System (ADS)

    Maekawa, T.; Nakamura, M.; Komatsu, T.; Kishino, T.; Kishigami, Y.; Makino, K.; Maehara, T.; Minami, T.; Hanada, K.; Iida, M.; Terumichi, Y.; Tanaka, S.

    1992-10-01

    The heat flux of fast electrons to the local limiter in LHCD plasmas in WT-3 has been investigated by thermal measurement of the limiter. The amount of the heat flux (PFE) is found to be about on third of the net radiofrequency power (Prf) injected into the plasma for various discharge conditions. The results combined with other measurements show that the confinement of fast electrons deteriorates as Prf increases. This direct loss of fast electrons is one of the causes of the degradation of the current drive efficiency. Heat transport of the bulk electrons is also found to increase as Prf increases. Experimental results indicate that a significant part of the remaining RF power (2Prf/3) flows to the bulk electrons. The slowing down power of fast electrons in the energy range above several tens of keV is estimated to be quite small compared with 2Prf/3, suggesting that a significant part of the remaining power flows to the bulk electrons via other channels. A plausible channel is the absorption of RF power via lower energy electrons by an upshift of the parallel refractive index of the injected lower hybrid waves. This seems to be another cause of the degradation of the current drive efficiency

  5. A fast, magnetics-free flux surface estimation and q-profile reconstruction algorithm for feedback control of plasma profiles

    NASA Astrophysics Data System (ADS)

    Hommen, G.; de Baar, M.; Citrin, J.; de Blank, H. J.; Voorhoeve, R. J.; de Bock, M. F. M.; Steinbuch, M.; contributors, JET-EFDA

    2013-02-01

    The flux surfaces' layout and the magnetic winding number q are important quantities for the performance and stability of tokamak plasmas. Normally, these quantities are iteratively derived by solving the plasma equilibrium for the poloidal and toroidal flux. In this work, a fast, non-iterative and magnetics-free numerical method is proposed to estimate the shape of the flux surfaces by an inward propagation of the plasma boundary shape, as can be determined for example by optical boundary reconstruction described in Hommen (2010 Rev. Sci. Instrum. 81 113504), toward the magnetic axis, as can be determined independently with the motional Stark effect (MSE) diagnostic. Flux surfaces are estimated for various plasma regimes in the ITER, JET and MAST tokamaks and are compared with results of CRONOS reconstructions and simulations, showing agreement to within 1% of the minor radius for almost all treated plasmas. The availability of the flux surface shapes combined with the pitch angles measured using MSE allow the reconstruction of the plasma q-profile, by evaluating the contour-integral over the flux surfaces of the magnetic field pitch angle. This method provides a direct and exact measure of the q-profile for arbitrary flux surface shapes, which does not rely on magnetic measurements. Results based on estimated flux surface shapes show agreement with CRONOS q-profiles of better than 10%. The impact of the shape of the flux surfaces on the q-profile, particularly the profiles of elongation and Shafranov shift, and offsets in plasma boundary and the magnetic axis are assessed. OFIT+ was conceived for real-time plasma profile control experiments and advanced tokamak operation, and provides quickly and reliably the mapping of actuators and sensors to the minor radius as well as the plasma q-profile, independent of magnetic measurements.

  6. Signal enhancement of neutral He emission lines by fast electron bombardment of laser-induced He plasma

    NASA Astrophysics Data System (ADS)

    Suyanto, Hery; Pardede, Marincan; Hedwig, Rinda; Marpaung, Alion Mangasi; Ramli, Muliadi; Lie, Tjung Jie; Abdulmadjid, Syahrun Nur; Kurniawan, Koo Hendrik; Tjia, May On; Kagawa, Kiichiro

    2016-08-01

    A time-resolved spectroscopic study is performed on the enhancement signals of He gas plasma emission using nanosecond (ns) and picosecond (ps) lasers in an orthogonal configuration. The ns laser is used for the He gas plasma generation and the ps laser is employed for the ejection of fast electrons from a metal target, which serves to excite subsequently the He atoms in the plasma. The study is focused on the most dominant He I 587.6 nm and He I 667.8 nm emission lines suggested to be responsible for the He-assisted excitation (HAE) mechanism. The time-dependent intensity enhancements induced by the fast electrons generated with a series of delayed ps laser ablations are deduced from the intensity time profiles of both He emission lines. The results clearly lead to the conclusion that the metastable excited triplet He atoms are actually the species overwhelmingly produced during the recombination process in the ns laser-induced He gas plasma. These metastable He atoms are believed to serve as the major energy source for the delayed excitation of analyte atoms in ns laser-induced breakdown spectroscopy (LIBS) using He ambient gas.

  7. Microwave plasma generation by the fast rotation and slow pulsation of resonant fields in a cylindrical cavity

    NASA Astrophysics Data System (ADS)

    Hasegawa, Yuichi; Nakamura, Keiji; Lubomirsky, Dima; Park, Soonam; Kobayashi, Satoru; Sugai, Hideo

    2017-04-01

    A digitally controlled solid-state microwave generator allowing variable frequency operation and precise phase control is adopted for plasma generation. In this study, a resonant cylindrical cavity is used as a microwave applicator in place of conventional waveguides. In order to improve the plasma uniformity, the TE111 mode is agitated by injecting microwaves into the cavity from two spatially orthogonal directions, with a temporal phase difference ϕ. Theoretical analyses and finite-difference time-domain simulations derive the following effects of the phase control. In the case of ϕ = ±π/2, fast rotation of the cavity field takes place with a rotational frequency of ω/2π (= 2.4–2.5 GHz), where ω denotes the microwave angular frequency. On the other hand, when ϕ is linearly modulated in time with a low frequency of Ω/2π (= 0.1–1000 Hz), slow pulsation takes place, in which the cavity field alternately excites a circular rotation and a standing oscillation at the modulation frequency. These effects are experimentally confirmed in microwave discharges in argon at 0.1–20 Torr with total injection powers from 50 to 800 W. Two-dimensional images of the optical emission from the generated plasma show that both the fast rotation and slow pulsation improve azimuthal plasma uniformity.

  8. Fast quantification of endogenous carbohydrates in plasma using hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry.

    PubMed

    Zhu, Bangjie; Liu, Feng; Li, Xituo; Wang, Yan; Gu, Xue; Dai, Jieyu; Wang, Guiming; Cheng, Yu; Yan, Chao

    2015-01-01

    Endogenous carbohydrates in biosamples are frequently highlighted as the most differential metabolites in many metabolomics studies. A simple, fast, simultaneous quantitative method for 16 endogenous carbohydrates in plasma has been developed using hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry. In order to quantify 16 endogenous carbohydrates in plasma, various conditions, including columns, chromatographic conditions, mass spectrometry conditions, and plasma preparation methods, were investigated. Different conditions in this quantified analysis were performed and optimized. The reproducibility, precision, recovery, matrix effect, and stability of the method were verified. The results indicated that a methanol/acetonitrile (50:50, v/v) mixture could effectively and reproducibly precipitate rat plasma proteins. Cold organic solvents coupled with vortex for 1 min and incubated at -20°C for 20 min were the most optimal conditions for protein precipitation and extraction. The results, according to the linearity, recovery, precision, matrix effect, and stability, showed that the method was satisfactory in the quantification of endogenous carbohydrates in rat plasma. The quantified analysis of endogenous carbohydrates in rat plasma performed excellently in terms of sensitivity, high throughput, and simple sample preparation, which met the requirement of quantification in specific expanded metabolomic studies after the global metabolic profiling research.

  9. Parametric Excitations of Fast Plasma Waves by Counter-propagating Laser Beams

    SciTech Connect

    G. Shvets; N.J. Fisch

    2001-03-19

    Short- and long-wavelength plasma waves can become strongly coupled in the presence of two counter-propagating laser pump pulses detuned by twice the cold plasma frequency. What makes this four-wave interaction important is that the growth rate of the plasma waves occurs much faster than in the more obvious co-propagating geometry.

  10. Modeling of fast neutral-beam-generated ions and rotation effects on RWM stability in DIII-D plasmas

    DOE PAGES

    Turco, Francesca; Turnbull, Alan D.; Hanson, Jeremy M.; ...

    2015-10-15

    Here, validation results for the MARS-K code for DIII-D equilibria, predict that the absence of fast Neutral Beam (NB) generated ions leads to a plasma response ~40–60% higher than in NB-sustained H-mode plasmas when the no-wall βN limit is reached. In a βN scan, the MARS-K model with thermal and fast-ions, reproduces the experimental measurements above the no-wall limit, except at the highest βN where the phase of the plasma response is overestimated. The dependencies extrapolate unfavorably to machines such as ITER with smaller fast ion fractions since elevated responses in the absence of fast ions indicate the potential onsetmore » of a resistive wall mode (RWM). The model was also tested for the effects of rotation at high βN, and recovers the measured response even when fast-ions are neglected, reversing the effect found in lower βN cases, but consistent with the higher βN results above the no-wall limit. The agreement in the response amplitude and phase for the rotation scan is not as good, and additional work will be needed to reproduce the experimental trends. In the case of current-driven instabilities, the magnetohydrodynamic spectroscopy system used to measure the plasma response reacts differently from that for pressure driven instabilities: the response amplitude remains low up to ~93% of the current limit, showing an abrupt increase only in the last ~5% of the current ramp. This makes it much less effective as a diagnostic for the approach to an ideal limit. However, the mode structure of the current driven RWM extends radially inwards, consistent with that in the pressure driven case for plasmas with qedge~2. This suggests that previously developed RWM feedback techniques together with the additional optimizations that enabled qedge~2 operation, can be applied to control of both current-driven and pressure-driven modes at high βN.« less

  11. Modeling of fast neutral-beam-generated ions and rotation effects on RWM stability in DIII-D plasmas

    SciTech Connect

    Turco, Francesca; Turnbull, Alan D.; Hanson, Jeremy M.; Navratil, Gerald A.

    2015-10-15

    Here, validation results for the MARS-K code for DIII-D equilibria, predict that the absence of fast Neutral Beam (NB) generated ions leads to a plasma response ~40–60% higher than in NB-sustained H-mode plasmas when the no-wall βN limit is reached. In a βN scan, the MARS-K model with thermal and fast-ions, reproduces the experimental measurements above the no-wall limit, except at the highest βN where the phase of the plasma response is overestimated. The dependencies extrapolate unfavorably to machines such as ITER with smaller fast ion fractions since elevated responses in the absence of fast ions indicate the potential onset of a resistive wall mode (RWM). The model was also tested for the effects of rotation at high βN, and recovers the measured response even when fast-ions are neglected, reversing the effect found in lower βN cases, but consistent with the higher βN results above the no-wall limit. The agreement in the response amplitude and phase for the rotation scan is not as good, and additional work will be needed to reproduce the experimental trends. In the case of current-driven instabilities, the magnetohydrodynamic spectroscopy system used to measure the plasma response reacts differently from that for pressure driven instabilities: the response amplitude remains low up to ~93% of the current limit, showing an abrupt increase only in the last ~5% of the current ramp. This makes it much less effective as a diagnostic for the approach to an ideal limit. However, the mode structure of the current driven RWM extends radially inwards, consistent with that in the pressure driven case for plasmas with qedge~2. This suggests that previously developed RWM feedback techniques together with the additional optimizations that enabled qedge~2 operation, can be applied to control of both current-driven and pressure-driven modes at high βN.

  12. Effects of corn type and fasting time before slaughter on growth and plasma index in weaning pigs.

    PubMed

    Yang, C; He, J; Chen, D W; Yu, B; Yu, J; Mao, X B; Yang, K Y; Yuan, Z C

    2016-01-01

    A 2 × 2 factorial experiment was conducted to evaluate the effects of dietary corn type (waxy corn [WC] vs. nonwaxy corn [NC]) and fasting period (2 h vs. 12-16 h) before slaughter on growth and plasma index in weaning pigs. Twenty-four crossbred barrows (8.26 ± 0.47 kg) were allotted to 4 treatments with 6 replications of 1 pig per replicate metabolism cage. Waxy corn contained less fat, a lower amylase:amylopectin ratio, more CP, and more starch than NC. Pigs fed the WC diet had lower jejunum digesta pH compared with those fed the NC diet ( < 0.05). Maltase activity in the jejunum and ileum mucosa ( < 0.01), sucrose activity in the ileum mucosa ( < 0.01), and amylase activity in the pancreas and jejunum digesta ( < 0.05) were increased in pigs fed the WC diet relative to those fed the NC diet. But the total tract apparent digestibility (TTAD) of starch and CP was lower for the WC group ( < 0.05). Ingestion of the NC diet resulted in higher ( < 0.05) ADG and ADFI in the second week but did not affect ADG ( = 0.091) and the feed:gain ratio (F:G; = 0.077) during the whole experiment period. The plasma glucose ( < 0.01) concentration was higher and high-density lipoprotein cholesterol (HDL-C; < 0.01) concentrations was lower in the hepatic portal vein in pigs fed the WC diet relative to those fed the NC diet. Fasting 2 h before slaughter decreased the jejunum and ileum digesta pH compared with the 12-h fasting group ( < 0.01). Villus height increased in the duodenum ( < 0.01) and jejunum ( < 0.05) and the villus height:crypt depth ratio increased in the duodenum ( < 0.05) of pigs after shortening the fasting period before slaughter. Shortening the fasting time before slaughter resulted in higher plasma glucose ( < 0.05) concentrations and a higher HDL-C:low-density lipoprotein cholesterol (LDL-C) ratio ( < 0.05) whereas the LDL-C ( < 0.05) concentrations were reduced in the hepatic portal vein. The results of this experiment indicate that although the production

  13. To Your Health: NLM update transcript - Beyond A1C for diabetes treatment

    MedlinePlus

    ... the 'resources' section of MedlinePlus.gov's A1C health topic page . The National Diabetes Education Program provides additional information ... the 'resources' section of MedlinePlus.gov's A1C health topic page. MedlinePlus.gov's A1C health topic page additionally provides ...

  14. Haemoglobin J-Baltimore can be detected by HbA1c electropherogram but with underestimated HbA1c value.

    PubMed

    Brunel, Valéry; Lahary, Agnčs; Chagraoui, Abdeslam; Thuillez, Christian

    2016-01-01

    Glycated haemoglobin (HbA(1c)) is considered the gold standard for assessing diabetes compensation and treatment. In addition, fortuitous detection of haemoglobin variants during HbA1c measurement is not rare. Recently, two publications reported different conclusions on accuracy of HbA(1c) value using capillary electrophoresis method in presence of haemoglobin J-Baltimore (HbJ).
Here we describe the fortuitous detection of unknown HbJ using capillary electrophoresis for measurement of HbA(1c). A patient followed for gestational diabetes in our laboratory presented unknown haemoglobin on Capillarys 2 Flex Piercing analyser which was identified as HbJ. HbJ is not associated with haematological abnormalities. High Performance Liquid Chromatography methods are known to possibly underestimate HbA(1c) value in the presence of this variant. This variant and its glycated form are clearly distinguished on electropherogram but HbJ was responsible for underestimating the true area of HbA(1c).
 Capillary electrophoresis is a good method for detecting HbJ but does not seem suitable for evaluation of HbA(1C) value in patients in presence of HbJ variant.

  15. Use of fructosyl peptide oxidase for HbA1c assay.

    PubMed

    Yonehara, Satoshi; Inamura, Norio; Fukuda, Miho; Sugiyama, Koji

    2015-03-01

    ARKRAY, Inc developed the world's first automatic glycohemoglobin analyzer based on HPLC (1981). After that, ARKRAY developed enzymatic HbA1c assay "CinQ HbA1c" with the spread and diversification of HbA1c measurement (2007). CinQ HbA1c is the kit of Clinical Chemistry Analyzer, which uses fructosyl peptide oxidase (FPOX) for a measurement reaction. This report mainly indicates the developmental background, measurement principle, and future of the enzymatic method HbA1c reagent.

  16. Fast ion motion in the plasma part of a stellarator-mirror fission-fusion hybrid

    NASA Astrophysics Data System (ADS)

    Moiseenko, V. E.; Nemov, V. V.; Ågren, O.; Kasilov, S. V.; Garkusha, I. E.

    2016-06-01

    Recent developments of a stellarator-mirror (SM) fission-fusion hybrid concept are reviewed. The hybrid consists of a fusion neutron source and a powerful sub-critical fast fission reactor core. The aim is transmutation of spent nuclear fuel and safe fission energy production. In its fusion part, a stellarator-type system with an embedded magnetic mirror is used. The stellarator confines deuterium plasma with moderate temperature, 1-2 keV. In the magnetic mirror, a hot component of sloshing tritium ions is trapped. There, the fusion neutrons are generated. A candidate for a combined SM system is a DRACON magnetic trap. A basic idea behind an SM device is to maintain local neutron production in a mirror part, but at the same time eliminate the end losses by using a toroidal device. A possible drawback is that the stellarator part can introduce collision-free radial drift losses, which is the main topic for this study. For high energy ions of tritium with an energy of 70 keV, comparative computations of collisionless losses in the rectilinear part of a specific design of the DRACON type trap are carried out. Two versions of the trap are considered with different lengths of the rectilinear sections. Also the total number of current-carrying rings in the magnetic system is varied. The results predict that high energy ions from neutral beam injection can be satisfactorily confined in the mirror part during 0.1-1 s. The Uragan-2M experimental device is used to check key points of the SM concept. The magnetic configuration of a stellarator with an embedded magnetic mirror is arranged in this device by switching off one toroidal coil. The motion of particles magnetically trapped in the embedded mirror is analyzed numerically with use of motional invariants. It is found that without radial electric field particles quickly drift out of the SM, even if the particles initially are located on a nested magnetic surface. We will show that a weak radial electric field, which

  17. Fast Plasma Investigation for MMS: Simulation of the Burst Triggering System

    NASA Technical Reports Server (NTRS)

    Barrie, A. C.; Dorelli, J. C.; Winkert, G. E.; Lobell, J. V.; Holland, M. P.; Adrian, M. L.; Pollock, C. J.

    2011-01-01

    The Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. To meet these requirements, the Fast Plasma Instrument (FPI) consists of eight (8) identical half top-hat electron sensors and eight (8) identical ion sensors and an Instrument Data Processing Unit (IDPU). The sensors (electron or ion) are grouped into pairs whose 6 degree x 180 degree fields-of-view (FOV) are set 90 degrees apart. Each sensor is equipped with electrostatic aperture steering to allow the sensor to scan a 45 degree x 180 degree fan about the its nominal viewing (0 deflection) direction. Each pair of sensors, known as the Dual Electron Spectrometer (DES) and the Dual Ion Spectrometer (DIS), occupies a quadrant on the MMS spacecraft and the combination of the eight electron/ion sensors, employing aperture steering, image the full-sky every 30-ms (electrons) and 150-ms (ions), respectively. To probe the diffusion regions of reconnection, the highest temporal/spatial resolution mode of FPI results in the DES complement of a given spacecraft generating 6.5-Mb (raised dot) per second of electron data while the DIS generates 1.1-Mb (raised dot) per second of ion data yielding an FPI total data rate of 6.6-Mb (raised dot) per second. The FPI electron/ion data is collected by the IDPU then transmitted to the Central Data Instrument Processor (CIDP) on the spacecraft for science interest ranking. Only data sequences that contain the greatest amount of temporal/spatial structure will be intelligently down-linked by the spacecraft. This requires a data ranking process known as the burst trigger system. The burst trigger system uses pseudo physical quantities to approximate the local plasma environments. As each pseudo quantity will have a different value, a set of two scaling factors is employed for each pseudo term. These pseudo

  18. Variations of High-Energy Ions during Fast Plasma Flows and Dipolarization in the Plasma Sheet: Comparison Among Different Ion Species

    NASA Astrophysics Data System (ADS)

    Ohtani, S.; Nose, M.; Miyashita, Y.; Lui, A.

    2014-12-01

    We investigate the responses of different ion species (H+, He+, He++, and O+) to fast plasma flows and local dipolarization in the plasma sheet in terms of energy density. We use energetic (9-210 keV) ion composition measurements made by the Geotail satellite at r = 10~31 RE. The results are summarized as follows: (1) whereas the O+-to-H+ ratio decreases with earthward flow velocity, it increases with tailward flow velocity with Vx dependence steeper for perpendicular flows than for parallel flows; (2) for fast earthward flows, the energy density of each ion species increases without any clear preference for heavy ions; (3) for fast tailward flows the ion energy density increases initially, then it decreases to below pre-flow levels except for O+; (4) the O+-to-H+ ratio does not increase through local dipolarization irrespective of dipolarization amplitude, background BZ, X distance, and VX; (5) in general, the H+ and He++ ions behave similarly. Result (1) can be attributed to radial transport along with the earthward increase of the background O+-to-H+ ratio. Results (2) and (4) indicate that ion energization associated with local dipolarization is not mass-dependent possibly because in the energy range of our interest the ions are not magnetized irrespective of species. In the tailward outflow region of reconnection, where the plasma sheet becomes thinner, the H+ ions escape along the field line more easily than the O+ ions, which possibly explains result (3). Result (5) suggests that the solar wind is the primary source of the high-energy H+ ions.

  19. Decreased expression of adipose CD36 and FATP1 are associated with increased plasma nonesterified fatty acids during prolonged fasting in northern elephant seal pups (Mirounga angustirostris)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The northern elephant seal undergoes a 2-3 month post-weaning fast during which it depends primarily on the oxidation of fatty acids to meet its energetic demands. The concentration of plasma free fatty acids (FFA) increases and is associated with the development of insulin resistance in late-fasted...

  20. CELLULOSE SYNTHASE INTERACTIVE1 Is Required for Fast Recycling of Cellulose Synthase Complexes to the Plasma Membrane in Arabidopsis

    PubMed Central

    Lei, Lei; Bashline, Logan; Li, Shundai

    2015-01-01

    Plants are constantly subjected to various biotic and abiotic stresses and have evolved complex strategies to cope with these stresses. For example, plant cells endocytose plasma membrane material under stress and subsequently recycle it back when the stress conditions are relieved. Cellulose biosynthesis is a tightly regulated process that is performed by plasma membrane-localized cellulose synthase (CESA) complexes (CSCs). However, the regulatory mechanism of cellulose biosynthesis under abiotic stress has not been well explored. In this study, we show that small CESA compartments (SmaCCs) or microtubule-associated cellulose synthase compartments (MASCs) are critical for fast recovery of CSCs to the plasma membrane after stress is relieved in Arabidopsis thaliana. This SmaCC/MASC-mediated fast recovery of CSCs is dependent on CELLULOSE SYNTHASE INTERACTIVE1 (CSI1), a protein previously known to represent the link between CSCs and cortical microtubules. Independently, AP2M, a core component in clathrin-mediated endocytosis, plays a role in the formation of SmaCCs/MASCs. Together, our study establishes a model in which CSI1-dependent SmaCCs/MASCs are formed through a process that involves endocytosis, which represents an important mechanism for plants to quickly regulate cellulose synthesis under abiotic stress. PMID:26443667

  1. Inaccuracy of haemoglobin A1c among HIV-infected men: effects of CD4 cell count, antiretroviral therapies and haematological parameters

    PubMed Central

    Slama, Laurence; Palella, Frank J.; Abraham, Alison G.; Li, Xiuhong; Vigouroux, Corinne; Pialoux, Gilles; Kingsley, Lawrence; Lake, Jordan E.; Brown, Todd T.; Margolick, Joseph B.; Crain, Barbara; Dobs, Adrian; Farzadegan, Homayoon; Gallant, Joel; Johnson-Hill, Lisette; Plankey, Michael; Sacktor, Ned; Selnes, Ola; Shepard, James; Thio, Chloe; Wolinsky, Steven M.; Phair, John P.; Badri, Sheila; O'Gorman, Maurice; Ostrow, David; Palella, Frank; Ragin, Ann; Detels, Roger; Martínez-Maza, Otoniel; Aronow, Aaron; Bolan, Robert; Breen, Elizabeth; Butch, Anthony; Jamieson, Beth; Miller, Eric N.; Oishi, John; Vinters, Harry; Wiley, Dorothy; Witt, Mallory; Yang, Otto; Young, Stephen; Zhang, Zuo Feng; Rinaldo, Charles R.; Kingsley, Lawrence A.; Becker, James T.; Cranston, Ross D.; Martinson, Jeremy J.; Mellors, John W.; Silvestre, Anthony J.; Stall, Ronald D.; Jacobson, Lisa P.; Munoz, Alvaro; Abraham, Alison; Althoff, Keri; Cox, Christopher; D'Souza, Gypsyamber; Golub, Elizabeth; Schollenberger, Janet; Seaberg, Eric C.; Su, Sol; Huebner, Robin E.; Dominguez, Geraldina

    2014-01-01

    Background There is limited evidence that among HIV-infected patients haemoglobin A1c (HbA1c) values may not accurately reflect glycaemia. We assessed HbA1c discordance (observed HbA1c − expected HbA1c) and associated factors among HIV-infected participants in the Multicenter AIDS Cohort Study (MACS). Methods Fasting glucose (FG) and HbA1c were measured at each semi-annual MACS visit since 1999. All HIV-infected and HIV-uninfected men for whom at least one FG and HbA1c pair measurement was available were evaluated. Univariate median regression determined the association between HbA1c and FG by HIV serostatus. The relationship between HbA1c and FG in HIV-uninfected men was used to determine the expected HbA1c. Generalized estimating equations determined factors associated with the Hb1Ac discordance among HIV-infected men. Clinically significant discordance was defined as observed HbA1c − expected HbA1c ≤−0.5%. Results Over 13 years, 1500 HIV-uninfected and 1357 HIV-infected men were included, with a median of 11 visits for each participant. At an FG of 125 mg/dL, the median HbA1c among HIV-infected men was 0.21% lower than among HIV-uninfected men and the magnitude of this effect increased with FG >126 mg/dL. Sixty-three percent of HIV-infected men had at least one visit with clinically significant HbA1c discordance, which was independently associated with: low CD4 cell count (<500 cells/mm3); a regimen containing a protease inhibitor, a non-nucleoside reverse transcriptase inhibitor or zidovudine; high mean corpuscular volume; and abnormal corpuscular haemoglobin. Conclusion HbA1c underestimates glycaemia in HIV-infected patients and its use in patients with risk factors for HbA1c discordance may lead to under-diagnosis and to under-treatment of established diabetes mellitus. PMID:25096078

  2. Detection of total and A1c-glycosylated hemoglobin in human whole blood using sandwich immunoassays on polydimethylsiloxane-based antibody microarrays.

    PubMed

    Chen, Huang-Han; Wu, Chih-Hsing; Tsai, Mei-Ling; Huang, Yi-Jing; Chen, Shu-Hui

    2012-10-16

    The percentage of glycosylated hemoglobin A1c (%GHbA1c) in human whole blood indicates the average plasma glucose concentration over a prolonged period of time and is used to diagnose diabetes. However, detecting GHbA1c in the whole blood using immunoassays has limited detection sensitivity due to its low percentage in total hemoglobin (tHb) and interference from various glycan moieties in the sample. We have developed a sandwich immunoassay using an antibody microarray on a polydimethylsiloxane (PDMS) substrate modified with fluorinated compounds to detect tHb and glycosylated hemoglobin A1c (GHbA1c) in human whole blood without sample pretreatment. A polyclonal antibody against hemoglobin (Hb) immobilized on PDMS is used as a common capture probe to enrich all forms of Hb followed by detection via monoclonal anti-Hb and specific monoclonal anti-GHbA1c antibodies for tHb and GHbA1c detection, respectively. This method prevents the use of glycan binding molecules and dramatically reduces the background interference, yielding a detection limit of 3.58 ng/mL for tHb and 0.20 ng/mL for GHbA1c. The fluorinated modification on PDMS is superior to the glass substrate and eliminates the need for the blocking step which is required in commercial enzyme linked immunosorbent assay (ELISA) kits. Moreover, the detection sensitivity for GHbA1c is 4-5 orders of magnitude higher, but the required sample amount is 25 times less than the commercial method. On the basis of patient sample data, a good linear correlation between %GHbA1c values determined by our method and the certified high performance liquid chromatography (HPLC) standard method is shown with R(2) > 0.98, indicating the great promise of the developed method for clinical applications.

  3. Glycated Hemoglobin (HbA1c): Clinical Applications of a Mathematical Concept

    PubMed Central

    Leow, Melvin Khee Shing

    2016-01-01

    Background and purpose: Glycated hemoglobin (HbA1c) reflects the cumulative glucose exposure of erythrocytes over a preceding time frame proportional to erythrocyte survival. HbA1c is thus an areal function of the glucose-time curve, an educationally useful concept to aid teaching and clinical judgment. Methods: An ordinary differential equation is formulated as a parsimonious model of HbA1c. The integrated form yields HbA1c as an area-under-the-curve (AUC) of a glucose-time profile. The rate constant of the HbA1c model is then derived using the validated regression equation in the ADAG study that links mean blood glucose and HbA1c with a very high degree of goodness-of-fit. Results: This model has didactic utility to enable patients, biomedical students and clinicians to appreciate how HbA1c may be conceptually inferred from discrete blood glucose values using continuous glucose monitoring system (CGMS) or self-monitored blood glucose (SMBG) glucometer readings as shown in the examples. It can be appreciated how hypoglycemia can occur with rapid HbA1c decline despite poor glycemic control. Conclusions: Being independent of laboratory assay pitfalls, computed ‘virtual’ HbA1c serves as an invaluable internal consistency cross-check against laboratory-measured HbA1c discordant with SMBG readings suggestive of inaccurate/fraudulent glucometer records or hematologic disorders including thalassemia and hemoglobinopathy. This model could be implemented within portable glucometers, CGMS devices and even smartphone apps for deriving tentative ‘virtual’ HbA1c from serial glucose readings as an adjunct to measured HbA1c. Such predicted ‘virtual’ HbA1c readily accessible via glucometers may serve as feedback to modify behavior and empower diabetic patients to achieve better glycemic control. PMID:27708483

  4. Genome-wide association meta-analysis identifies novel variants associated with fasting plasma glucose in East Asians.

    PubMed

    Hwang, Joo-Yeon; Sim, Xueling; Wu, Ying; Liang, Jun; Tabara, Yasuharu; Hu, Cheng; Hara, Kazuo; Tam, Claudia H T; Cai, Qiuyin; Zhao, Qi; Jee, Sunha; Takeuchi, Fumihiko; Go, Min Jin; Ong, Rick Twee Hee; Ohkubo, Takayoshi; Kim, Young Jin; Zhang, Rong; Yamauchi, Toshimasa; So, Wing Yee; Long, Jirong; Gu, Dongfeng; Lee, Nanette R; Kim, Soriul; Katsuya, Tomohiro; Oh, Ji Hee; Liu, Jianjun; Umemura, Satoshi; Kim, Yeon-Jung; Jiang, Feng; Maeda, Shiro; Chan, Juliana C N; Lu, Wei; Hixson, James E; Adair, Linda S; Jung, Keum Ji; Nabika, Toru; Bae, Jae-Bum; Lee, Mi Hee; Seielstad, Mark; Young, Terri L; Teo, Yik Ying; Kita, Yoshikuni; Takashima, Naoyuki; Osawa, Haruhiko; Lee, So-Hyun; Shin, Min-Ho; Shin, Dong Hoon; Choi, Bo Youl; Shi, Jiajun; Gao, Yu-Tang; Xiang, Yong-Bing; Zheng, Wei; Kato, Norihiro; Yoon, Miwuk; He, Jiang; Shu, Xiao Ou; Ma, Ronald C W; Kadowaki, Takashi; Jia, Weiping; Miki, Tetsuro; Qi, Lu; Tai, E Shyong; Mohlke, Karen L; Han, Bok-Ghee; Cho, Yoon Shin; Kim, Bong-Jo

    2015-01-01

    Fasting plasma glucose (FPG) has been recognized as an important indicator for the overall glycemic state preceding the onset of metabolic diseases. So far, most indentified genome-wide association loci for FPG were derived from populations with European ancestry, with a few exceptions. To extend a thorough catalog for FPG loci, we conducted meta-analyses of 13 genome-wide association studies in up to 24,740 nondiabetic subjects with East Asian ancestry. Follow-up replication analyses in up to an additional 21,345 participants identified three new FPG loci reaching genome-wide significance in or near PDK1-RAPGEF4, KANK1, and IGF1R. Our results could provide additional insight into the genetic variation implicated in fasting glucose regulation.

  5. Quantification of the nonenzymatic fast and slow TRAP in a postaddition assay in human seminal plasma and the antioxidant contributions of various seminal compounds.

    PubMed

    Rhemrev, J P; van Overveld, F W; Haenen, G R; Teerlink, T; Bast, A; Vermeiden, J P

    2000-01-01

    Total radical-trapping antioxidant potential (TRAP) measurements of human seminal plasma (N = 25) were performed by using a post-addition assay based on trapping 2,2' Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radicals. This method enables the antioxidant capacity of human seminal plasma and its constituents to be quantified. The standard procedure consisted of determination of the Trolox equivalent antioxidant capacity (TEAC) after incubating the test sample in the ABTS radical solution for 10 seconds (fast TRAP) and 300 s (total TRAP). Interestingly, seminal plasma showed a fast TRAP and a high slow TRAP (Total TRAP - Fast TRAP). The final total TRAP of seminal plasma is about 10 times higher than that of blood plasma. Various components of seminal plasma contribute to its fast TRAP; 37% can be attributed to vitamin C, uric acid, and tyrosine; proteins and polyphenolic compounds contribute a further 57%. In contrast, the slow TRAP was attributed to vitamin C (1%), uric acid (2%), and tyrosine (15%) and to proteins and polyphenolic compounds (33%). It was not possible to account for the remaining 49%. Neither known putative antioxidants, such as spermine, pyruvate, and taurine, nor other seminal compounds, such as carnitine, sialic acid, fructose, spermidine, glycerophosphorylcholine, and hyaluronic acid, contributed to any significant radical-trapping activity at a standard concentration of 1 mM. Of the amino acids, only tyrosine possessed a slow TRAP, and it is present at a high concentration in seminal plasma. Glutathione and hypotaurine show high fast and slow TRAPs, respectively. However, because of their low concentration in seminal plasma, their contribution to the TRAP is negligible. In conclusion, seminal plasma possesses a high antioxidant buffer capacity that protects spermatozoa from oxidative stress. Moreover, these findings suggest that the fast and slow TRAPs may have an important role as infertility markers and treatment targets in

  6. Fast low-temperature plasma reduction of monolayer graphene oxide at atmospheric pressure.

    PubMed

    Bodik, Michal; Zahoranova, Anna; Micusik, Matej; Bugarova, Nikola; Spitalsky, Zdenko; Omastova, Maria; Majkova, Eva; Jergel, Matej; Siffalovic, Peter

    2017-04-07

    We report on an ultrafast plasma-based graphene oxide reduction method superior to conventional vacuum thermal annealing and/or chemical reduction. The method is based on the effect of non-equilibrium atmospheric-pressure plasma generated by the diffuse coplanar surface barrier discharge in proximity of the graphene oxide layer. As the reduction time is in the order of seconds, the presented method is applicable to the large-scale production of reduced graphene oxide layers. The short reduction times are achieved by the high-volume power density of plasma, which is of the order of 100 W cm(-3). Monolayers of graphene oxide on silicon substrate were prepared by a modified Langmuir-Schaefer method and the efficient and rapid reduction by methane and/or hydrogen plasma was demonstrated. The best results were obtained for the graphene oxide reduction in hydrogen plasma, as verified by x-ray photoelectron spectroscopy and Raman spectroscopy.

  7. Fast low-temperature plasma reduction of monolayer graphene oxide at atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Bodik, Michal; Zahoranova, Anna; Micusik, Matej; Bugarova, Nikola; Spitalsky, Zdenko; Omastova, Maria; Majkova, Eva; Jergel, Matej; Siffalovic, Peter

    2017-04-01

    We report on an ultrafast plasma-based graphene oxide reduction method superior to conventional vacuum thermal annealing and/or chemical reduction. The method is based on the effect of non-equilibrium atmospheric-pressure plasma generated by the diffuse coplanar surface barrier discharge in proximity of the graphene oxide layer. As the reduction time is in the order of seconds, the presented method is applicable to the large-scale production of reduced graphene oxide layers. The short reduction times are achieved by the high-volume power density of plasma, which is of the order of 100 W cm‑3. Monolayers of graphene oxide on silicon substrate were prepared by a modified Langmuir–Schaefer method and the efficient and rapid reduction by methane and/or hydrogen plasma was demonstrated. The best results were obtained for the graphene oxide reduction in hydrogen plasma, as verified by x-ray photoelectron spectroscopy and Raman spectroscopy.

  8. Where does plasma methylglyoxal originate from?

    PubMed

    Kalapos, Miklós Péter

    2013-03-01

    The elevation of plasma methylglyoxal levels in diabetic humans is widely observed, but it is unknown to what extent different sources of methylglyoxal contribute to its plasma concentration. A retrospective analysis of clinical findings has been undertaken. There is controversy about the correlation of plasma methylglyoxal concentrations with fasting or postprandial glucose levels, and the relationship with HbA1c. There is only one study in which plasma ketone body levels have been monitored in parallel with methylglyoxal and a positive correlation between plasma methylglyoxal and β-hydroxybutyrate was observed. There are no reports on plasma aminoacetone levels and methylglyoxal in diabetic humans. This paper suggests that although there is a close association between methylglyoxal and carbohydrate metabolism, the presence of this 1,2-dicarbonyl in the plasma is mainly due to other mechanisms. Protein glycation and aminoacetone degradation are proposed to be the major and the minor sources of plasma methylglyoxal under normal conditions.

  9. Effects of fast halogen and plasma arc curing lights on the surface hardness of orthodontic adhesives for lingual retainers.

    PubMed

    Uşümez, Serdar; Büyükyilmaz, Tamer; Karaman, Ali Ihya

    2003-06-01

    The aims of this study were to (1) identify the optimum cure times of 2 different lingual retainer adhesives with a conventional halogen, a fast halogen, and a plasma arc light by measuring Vickers surface hardness, and (2) determine whether different lights produce similar surface hardness values for the same adhesive resin material. The investigated plasma arc curing unit was the PowerPac (American Dental Technologies, Corpus Christi, Tex), and the fast halogen unit was the Optilux 501 (Kerr, Orange, Calif). A conventional curing unit, the Ortholux XT (3M Dental Products, St. Paul, Minn) was used as the control. Two orthodontic lingual retainer adhesives were used: Transbond Lingual Retainer (3M Unitek, Monrovia, Calif) and Light Cure Retainer (Reliance Orthodontic Products, Itasca, Ill). Concise (3M Dental Products) and diluted Concise were used as controls. Transbond Lingual Retainer was polymerized by the PowerPac light in 6 seconds, by the Optilux in 10 seconds, and by the conventional halogen light in 20 seconds. The minimum curing times for Light Cure Retainer adhesive were 15 seconds for PowerPac, 10 seconds for Optilux, and 40 seconds for conventional halogen. Surface hardness values for each resin did not differ significantly with different curing units. However, different adhesives demonstrated significantly different surface hardness values. Final Vickers surface hardness values (averaged across curing units) of Transbond Lingual Retainer, Concise, diluted Concise, and Light Cure Retainer were 62.8, 52.4, 46.0, and 40.4, respectively. Plasma arc or fast halogen units polymerize resin composite adhesive in much shorter times than do conventional curing units, without a significant loss in surface hardness. Therefore, these units are suggested for clinical use to save chairside time.

  10. Current drive with combined electron cyclotron wave and high harmonic fast wave in tokamak plasmas

    NASA Astrophysics Data System (ADS)

    Li, J. C.; Gong, X. Y.; Dong, J. Q.; Wang, J.; Zhang, N.; Zheng, P. W.; Yin, C. Y.

    2016-12-01

    The current driven by combined electron cyclotron wave (ECW) and high harmonic fast wave is investigated using the GENRAY/CQL3D package. It is shown that no significant synergetic current is found in a range of cases with a combined ECW and fast wave (FW). This result is consistent with a previous study [Harvey et al., in Proceedings of IAEA TCM on Fast Wave Current Drive in Reactor Scale Tokamaks (Synergy and Complimentarily with LHCD and ECRH), Arles, France, IAEA, Vienna, 1991]. However, a positive synergy effect does appear with the FW in the lower hybrid range of frequencies. This positive synergy effect can be explained using a picture of the electron distribution function induced by the ECW and a very high harmonic fast wave (helicon). The dependence of the synergy effect on the radial position of the power deposition, the wave power, the wave frequency, and the parallel refractive index is also analyzed, both numerically and physically.

  11. Physical processes taking place in dense plasma focus devices at the interaction of hot plasma and fast ion streams with materials under test

    NASA Astrophysics Data System (ADS)

    Gribkov, V. A.

    2015-06-01

    The dense plasma focus (DPF) device represents a source of powerful streams of penetrating radiations (hot plasma, fast electron and ion beams, x-rays and neutrons) of ns-scale pulse durations. Power flux densities of the radiation types may reach in certain cases the values up to 1013 W cm  -  2. They are widely used at present time in more than 30 labs in the world in the field of radiation material science. Areas of their implementations are testing of the materials perspective for use in modern fusion reactors (FR) of both types, modification of surface layers with an aim of improvements their properties, production of some nanostructures on their surface, and so on. To use a DPF correctly in these applications it is important to understand the mechanisms of generation of the above-mentioned radiations, their dynamics inside and outside of the pinch and processes of interaction of these streams with targets. In this paper, the most important issues on the above matter we discuss in relation to the cumulative hot plasma stream and the beam of fast ions with illustration of experimental results obtained at four DPF devices ranged in the limits of bank energies from 1 kJ to 1 MJ. Among them mechanisms of a jet formation, a current abruption phenomenon, a super-Alfven ion beam propagation inside and outside of DPF plasma, generation of secondary plasma and formation of shock waves in plasma and inside a solid-state target, etc. Nanosecond time-resolved techniques (electric probes, laser interferometry, frame self-luminescent imaging, x-ray/neutron probes, etc) give an opportunity to investigate the above-mentioned events and to observe the process of interaction of the radiation types with targets. After irradiation, we analyzed the specimens by contemporary instrumentation: optical and scanning electron microscopy, local x-ray spectral and structure analysis, atomic force microscopy, the portable x-ray diffractometer that combines x-ray single

  12. Two Dual Ion Spectrometer Flight Units of the Fast Plasma Instrument Suite (FPI) for the Magnetospheric Multiscale Mission (MMS)

    NASA Technical Reports Server (NTRS)

    Adams, Mitzi

    2014-01-01

    Two Dual Ion Spectrometer flight units of the Fast Plasma Instrument Suite (FPI) for the Magnetospheric Multiscale Mission (MMS) have returned to MSFC for flight testing. Anticipated to begin on June 30, tests will ensue in the Low Energy Electron and Ion Facility of the Heliophysics and Planetary Science Office (ZP13), managed by Dr. Victoria Coffey of the Natural Environments Branch of the Engineering Directorate (EV44). The MMS mission consists of four identical spacecraft, whose purpose is to study magnetic reconnection in the boundary regions of Earth's magnetosphere.

  13. Fishbones in Joint European Torus plasmas with high ion-cyclotron-resonance-heated fast ions energy content

    SciTech Connect

    Nabais, F.; Borba, D.; Mantsinen, M.; Nave, M.F.F.; Sharapov, S.E.; Joint

    2005-10-01

    In Joint European Torus (JET) [P. J. Lomas, Plasma Phys. Controled Fusion 31, 1481 (1989)], discharges with ion cyclotron resonance heating only, low-density plasmas and high fast ions energy contents provided a scenario where fishbones behavior has been observed to be related with sawtooth activity: Crashes of monster sawteeth abruptly changed the type of observed fishbones from low-frequency fishbones [B. Coppi and F. Porcelli, Phys. Rev. Lett. 57, 2272 (1986)] to high-frequency fishbones [L. Chen, R. White, and M. Rosenbluth, Phys. Rev. Lett. 52, 1122 (1984)]. During periods between crashes, the type of observed fishbones gradually changed in the opposite way. Two new fishbones regimes have been observed in intermediate stages: Fishbones bursts covering both high and low frequencies and low amplitude bursts of both types occurring simultaneously. Both sawtooth and fishbones behavior have been explained using a variational formalism.

  14. ITER Plasma at Ion Cyclotron Frequency Domain: The Fusion Alpha Particles Diagnostics Based on the Stimulated Raman Scattering of Fast Magnetosonic Wave off High Harmonic Ion Bernstein Modes

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2014-10-01

    A novel method for alpha particle diagnostics is proposed. The theory of stimulated Raman scattering, SRS, of the fast wave and ion Bernstein mode, IBM, turbulence in multi-ion species plasmas, (Stefan University Press, La Jolla, CA, 2008). is utilized for the diagnostics of fast ions, (4)He (+2), in ITER plasmas. Nonlinear Landau damping of the IBM on fast ions near the plasma edge leads to the space-time changes in the turbulence level, (inverse alpha particle channeling). The space-time monitoring of the IBM turbulence via the SRS techniques may prove efficient for the real time study of the fast ion velocity distribution function, spatial distribution, and transport. Supported by Nikola Tesla Labs., La Jolla, CA 92037.

  15. Investigation of fast-electron-induced Kα x rays in laser-produced blow-off plasma

    NASA Astrophysics Data System (ADS)

    Sawada, H.; Wei, M. S.; Chawla, S.; Morace, A.; Akli, K.; Yabuuchi, T.; Nakanii, N.; Key, M. H.; Patel, P. K.; Mackinnon, A. J.; McLean, H. S.; Stephens, R. B.; Beg, F. N.

    2014-03-01

    Refluxing of fast electrons generated by high-intensity, short-pulse lasers was investigated by measuring electron-induced Kα x rays from a buried tracer layer. Using planar foils of Au/Cu/CH, the 150-J, 0.7-ps TITAN short-pulse laser was focused on the gold foil to generate fast electrons and the 3-ns, 300-J long pulse beam irradiated on the CH side to create expanding plasma as a conducting medium. By delaying the short-pulse beam timing from the long pulse laser irradiation, the plasma size was varied to change electron refluxing in the target rear. The total yields and two-dimensional images of 8.05-keV Cu-Kα x ray were recorded with an x-ray spectrometer and two monochromatic crystal imagers. The measurements show that the integrated yields decrease by a factor of 10 from refluxing to the nonrefluxing limit. Similar radial profiles of the Kα images in the rear were observed at all delays. Hybrid-particle-in-cell simulations using plasma profiles calculated by a radiation-hydrodynamic code HYDRA agree well with the measured Kα yields. The simulations suggest that conducting plasma with the size of ˜300 μm in the laser direction and ˜600 μm in the lateral direction at the density of 2 × 1020 1/cm3 is sufficiently large to prevent electrons from refluxing in the target. The parameters found in this study can be useful in designing experiments utilizing a Kα x-ray source in refluxing regime or a tracer layer in nonrefluxing regime.

  16. Investigation of fast-electron-induced Kα x rays in laser-produced blow-off plasma.

    PubMed

    Sawada, H; Wei, M S; Chawla, S; Morace, A; Akli, K; Yabuuchi, T; Nakanii, N; Key, M H; Patel, P K; Mackinnon, A J; McLean, H S; Stephens, R B; Beg, F N

    2014-03-01

    Refluxing of fast electrons generated by high-intensity, short-pulse lasers was investigated by measuring electron-induced Kα x rays from a buried tracer layer. Using planar foils of Au/Cu/CH, the 150-J, 0.7-ps TITAN short-pulse laser was focused on the gold foil to generate fast electrons and the 3-ns, 300-J long pulse beam irradiated on the CH side to create expanding plasma as a conducting medium. By delaying the short-pulse beam timing from the long pulse laser irradiation, the plasma size was varied to change electron refluxing in the target rear. The total yields and two-dimensional images of 8.05-keV Cu-Kα x ray were recorded with an x-ray spectrometer and two monochromatic crystal imagers. The measurements show that the integrated yields decrease by a factor of 10 from refluxing to the nonrefluxing limit. Similar radial profiles of the Kα images in the rear were observed at all delays. Hybrid-particle-in-cell simulations using plasma profiles calculated by a radiation-hydrodynamic code HYDRA agree well with the measured Kα yields. The simulations suggest that conducting plasma with the size of ∼300 μm in the laser direction and ∼600 μm in the lateral direction at the density of 2 × 1020 1/cm3 is sufficiently large to prevent electrons from refluxing in the target. The parameters found in this study can be useful in designing experiments utilizing a Kα x-ray source in refluxing regime or a tracer layer in nonrefluxing regime.

  17. Characteristics of a fast rise time power supply for a pulsed plasma reactor for chemical vapor destruction

    SciTech Connect

    Lawless, P.A.; Yamamoto, Toshiaki; Shofran, S.P.; Boss, C.B.; Nunez, C.M.; Ramsey, G.H.; Engels, R.L.

    1996-11-01

    Rotating spark gap devices for switching high-voltage direct current (dc) into a corona plasma reactor can achieve pulse rise times in the range of tens of nanoseconds. The fast rise times lead to vigorous plasma generation without sparking at instantaneous applied voltages higher than can be obtained with dc. The resulting energetic plasma is effective for destroying a variety of molecules. The spark gap circuit configuration plays an important role in the effectiveness of the plasma generation. A single-gap circuit is effective for generating moderate peak voltages, but is limited by a multiple sparking phenomenon. A double-gap circuit can achieve equal peak voltages with every spark, but with a reduced number of pulses, compared to the single gap. Both configurations have an upper voltage imposed by the changing impedance of the reactor as voltage and frequency are varied. The pulse characteristics are reported for both types of circuits. The general performance of the reactors for destruction of some compounds with both circuits is also reported.

  18. PROGENS-HbA1c study: safety and effectiveness of premixed recombinant human insulin (Gensulin M30)

    PubMed Central

    Walicka, Magdalena; Jóźwiak, Jacek; Rzeszotarski, Jacek; Zarzycka-Lindner, Grażyna; Zonenberg, Anna; Bijoś, Paweł; Masierek, Małgorzata

    2016-01-01

    Introduction Insulin analogues have gained widespread popularity. However, in many countries the use of these drugs is limited by their relatively high cost, so there is still a need for more cost-effective human insulin therapies. The aim of the study was to assess the effectiveness and safety of the premixed recombinant human insulin (rhuI) Gensulin M30 in a real-life setting. Material and methods The study group consisted of 4257 patients (2196 female, 2061 male) with type 2 diabetes, aged 63.7 ±9.4, with body mass index (BMI) 30.3 ±4.5 kg/m2 and diabetes duration 9 ±5.5 years. All patients were treated with premixed rhuI Gensulin M30. In 91.7% of patients, insulin was used in combination with metformin. In 3.7% of patients, it was used with sulphonylureas. The patients were observed for a period of 6 months. Results The total insulin dose on visit 1 was 36.1 ±18.7 U (0.42 ±0.22 U/kg), and by the end of the study it reached 40.3 ±18.9 U (0.48 ±0.22 U/kg). A significant, continuous decrease of the levels of glycated hemoglobin (HbA1c), along with fasting and postprandial plasma glucose, was observed during the study period. The frequency of hypoglycemia increased slightly during the study, although these figures remained low, especially with regard to severe hypoglycemic episodes (0.02 episodes/patient/year). The lowest number of hypoglycemic episodes occurred in patients treated with insulin and metformin, while the highest number of episodes was observed in patients treated with insulin alone. No weight changes were noted in the patients during the study. Conclusions This study shows rhuI Gensulin M30 to be effective and safe in a real-life setting. PMID:27695488

  19. Equation-of-state measurement of dense plasmas heated with fast protons.

    PubMed

    Dyer, G M; Bernstein, A C; Cho, B I; Osterholz, J; Grigsby, W; Dalton, A; Shepherd, R; Ping, Y; Chen, H; Widmann, K; Ditmire, T

    2008-07-04

    Using an ultrafast pulse of mega-electron-volt energy protons accelerated from a laser-irradiated foil, we have heated solid density aluminum plasmas to temperatures in excess of 15 eV. By measuring the temperature and the expansion rate of the heated Al plasma simultaneously and with picosecond time resolution we have found the predictions of the SESAME Livermore equation-of-state (LEOS) tables to be accurate to within 18%, in this dense plasma regime, where there have been few previous experimental measurements.

  20. Equation-of-State Measurement of Dense Plasmas Heated With Fast Protons

    SciTech Connect

    Dyer, G. M.; Bernstein, A. C.; Cho, B. I.; Osterholz, J.; Grigsby, W.; Dalton, A.; Ditmire, T.; Shepherd, R.; Ping, Y.; Chen, H.; Widmann, K.

    2008-07-04

    Using an ultrafast pulse of mega-electron-volt energy protons accelerated from a laser-irradiated foil, we have heated solid density aluminum plasmas to temperatures in excess of 15 eV. By measuring the temperature and the expansion rate of the heated Al plasma simultaneously and with picosecond time resolution we have found the predictions of the SESAME Livermore equation-of-state (LEOS) tables to be accurate to within 18%, in this dense plasma regime, where there have been few previous experimental measurements.

  1. Equation-of-State Measurement of Dense Plasmas Heated With Fast Protons

    NASA Astrophysics Data System (ADS)

    Dyer, G. M.; Bernstein, A. C.; Cho, B. I.; Osterholz, J.; Grigsby, W.; Dalton, A.; Shepherd, R.; Ping, Y.; Chen, H.; Widmann, K.; Ditmire, T.

    2008-07-01

    Using an ultrafast pulse of mega-electron-volt energy protons accelerated from a laser-irradiated foil, we have heated solid density aluminum plasmas to temperatures in excess of 15 eV. By measuring the temperature and the expansion rate of the heated Al plasma simultaneously and with picosecond time resolution we have found the predictions of the SESAME Livermore equation-of-state (LEOS) tables to be accurate to within 18%, in this dense plasma regime, where there have been few previous experimental measurements.

  2. Effect of Iron Deficiency Anemia on Hemoglobin A1c Levels

    PubMed Central

    Sinha, Nitin; Mishra, T.K.; Singh, Tejinder

    2012-01-01

    Background Iron deficiency anemia is the most common form of anemia in India. Hemoglobin A1c (HbA1c) is used in diabetic patients as an index of glycemic control reflecting glucose levels of the previous 3 months. Like blood sugar levels, HbA1c levels are also affected by the presence of variant hemoglobins, hemolytic anemias, nutritional anemias, uremia, pregnancy, and acute blood loss. However, reports on the effects of iron deficiency anemia on HbA1c levels are inconsistent. We conducted a study to analyze the effects of iron deficiency anemia on HbA1c levels and to assess whether treatment of iron deficiency anemia affects HbA1c levels. Methods Fifty patients confirmed to have iron deficiency anemia were enrolled in this study. HbA1c and absolute HbA1c levels were measured both at baseline and at 2 months after treatment, and these values were compared with those in the control population. Results The mean baseline HbA1c level in anemic patients (4.6%) was significantly lower than that in the control group (5.5%, p<0.05). A significant increase was observed in the patients' absolute HbA1c levels at 2 months after treatment (0.29 g/dL vs. 0.73 g/dL, p<0.01). There was a significant difference between the baseline values of patients and controls (0.29 g/dL vs. 0.74 g/dL, p<0.01). Conclusions In contrast to the observations of previous studies, ours showed that HbA1c levels and absolute HbA1c levels increased with treatment of iron deficiency anemia. This could be attributable to nutritional deficiency and/or certain unknown variables. Further studies are warranted. PMID:22259774

  3. A Dietary Supplement Containing Cinnamon, Chromium and Carnosine Decreases Fasting Plasma Glucose and Increases Lean Mass in Overweight or Obese Pre-Diabetic Subjects: A Randomized, Placebo-Controlled Trial

    PubMed Central

    Liu, Yuejun; Cotillard, Aurélie; Vatier, Camille; Bastard, Jean-Philippe; Fellahi, Soraya; Stévant, Marie; Allatif, Omran; Langlois, Clotilde; Bieuvelet, Séverine; Brochot, Amandine; Guilbot, Angèle; Clément, Karine; Rizkalla, Salwa W.

    2015-01-01

    Background Preventing or slowing the progression of prediabetes to diabetes is a major therapeutic issue. Objectives Our aim was to evaluate the effects of 4-month treatment with a dietary supplement containing cinnamon, chromium and carnosine in moderately obese or overweight pre-diabetic subjects, the primary outcome being change in fasting plasma glucose (FPG) level. Other parameters of plasma glucose homeostasis, lipid profile, adiposity and inflammatory markers were also assessed. Methods In a randomized, double-blind, placebo-controlled study, 62 subjects with a FPG level ranging from 5.55 to 7 mmol/L and a body mass index ≥25 kg/m2, unwilling to change their dietary and physical activity habits, were allocated to receive a 4-month treatment with either 1.2 g/day of the dietary supplement or placebo. Patients were followed up until 6 months post-randomization. Results Four-month treatment with the dietary supplement decreased FPG compared to placebo (-0.24±0.50 vs +0.12±0.59 mmol/L, respectively, p = 0.02), without detectable significant changes in HbA1c. Insulin sensitivity markers, plasma insulin, plasma lipids and inflammatory markers did not differ between the treatment groups. Although there were no significant differences in changes in body weight and energy or macronutrient intakes between the two groups, fat-free mass (%) increased with the dietary supplement compared to placebo (p = 0.02). Subjects with a higher FPG level and a milder inflammatory state at baseline benefited most from the dietary supplement. Conclusions Four-month treatment with a dietary supplement containing cinnamon, chromium and carnosine decreased FPG and increased fat-free mass in overweight or obese pre-diabetic subjects. These beneficial effects might open up new avenues in the prevention of diabetes. Trial Registration ClinicalTrials.gov NCT01530685 PMID:26406981

  4. LIF and fast imaging plasma jet characterization relevant for NTP biomedical applications

    NASA Astrophysics Data System (ADS)

    Riès, D.; Dilecce, G.; Robert, E.; Ambrico, P. F.; Dozias, S.; Pouvesle, J.-M.

    2014-07-01

    In the field of biomedical application, many publications report on non-thermal plasma jet potentialities for cell behaviour modifications in cancer treatment, wound healing or sterilization. However most previous plasma jet characterizations were performed when jets expend freely in air. Only recently has the influence of the targeted surface been properly considered. In this work, modifications induced by various types of targets, mimicking the biological samples, in the plasma propagation and production of hydroxyl radicals are evidenced through time-resolved intensified charge-coupled device imaging and laser-induced fluorescence (LIF) measurements. A LIF model, also specifically dedicated to estimate air and water penetration inside the jet, is used and proves to be well adapted to characterize the plasma jet under biomedical application conditions. It is shown that the plasma produced by the plasma gun counter-propagates after impinging the surface which, for the same operating parameters, leads to an increase of almost one order of magnitude in the maximum OH density (from ˜2 × 1013 cm-3 for open-air propagation to ˜1 × 1014 cm-3 for a grounded metal target). The nature of the target, especially its electrical conductivity, as well as gas flow rate and voltage amplitude are playing a key role in the production of hydroxyl radicals. The strong interplay between gas flow dynamics and plasma propagation is here confirmed by air and water distribution measurements. The need for a multi-diagnostic approach, as well as great care in setting up the in situ characterization of plasma jets, is here emphasized. Special attention must not only be paid to voltage amplitude and gas flow rate but also to the nature, humidity and conductivity of the target.

  5. Fast multidimensional model for the simulation of Raman amplification in plasma.

    PubMed

    Farmer, J P; Pukhov, A

    2013-12-01

    We present Leap, a simulation model for Raman amplification in plasma, combining an envelope treatment of the laser fields with an electrostatic particle-in-cell solver. The code is fully two dimensional, with the model readily extendible to three dimensions, and includes dispersive and refractive effects. Simulations carried out for Raman amplification in a plasma channel show that guiding of both the pump and the probe contribute to the evolution of the probe, resulting in a shorter, more intense pulse.

  6. Systematic review and meta-analysis reveals acutely elevated plasma cortisol following fasting but not less severe calorie restriction.

    PubMed

    Nakamura, Yuko; Walker, Brian R; Ikuta, Toshikazu

    2016-01-01

    Elevated plasma cortisol has been reported following caloric restriction, and may contribute to adverse effects including stress-induced overeating, but results from published studies are inconsistent. To clarify the effects of caloric restriction on plasma cortisol, and to assess cortisol as an indicator of stress during caloric restriction, we conducted a systematic review and meta-analysis of published studies in which cortisol was measured following caloric restriction without other manipulations in humans. We further compared effects of fasting, very low calorie diet (VLCD), and other less intense low calorie diet (LCD), as well as the duration of caloric restriction by meta-regression. Overall, caloric restriction significantly increased serum cortisol level in 13 studies (357 total participants). Fasting showed a very strong effect in increasing serum cortisol, while VLCD and LCD did not show significant increases. The meta-regression analysis showed a negative association between the serum cortisol level and the duration of caloric restriction, indicating serum cortisol is increased in the initial period of caloric restriction but decreased to the baseline level after several weeks. These results suggest that severe caloric restriction causes activation of the hypothalamic-pituitary-adrenal axis, which may be transient, but results in elevated cortisol which could mediate effects of starvation on brain and metabolic function as well as ameliorate weight loss.

  7. [Indicators of glycemic control --hemoglobin A1c (HbA1c), glycated albumin (GA), and 1,5-anhydroglucitol (1,5-AG)].

    PubMed

    Sato, Asako

    2014-01-01

    The clinical goal of diabetes management is a good quality of life that is not different from that of a healthy subjects. To fulfill the goal, prevention of complications is needed under good glycemic control. Although blood glucose measurement is essential for glycemic control, there are diurnal variations in blood glucose levels. An indicator of long-term glycemic control is necessary. HbA1c is the gold standard measurement for the assessment of glycemic control, and worldwide large scale clinical studies of diabetes complications have greatly valued HbA1c as an indicator of glycemic control. In addition, recently, HbA1c was recommended for use in the diagnosis of diabetes in Japan and in the United States. Although HbA1c is used widely and internationally, international standardization of the HbA1c value has not been achieved. In Japan, from April 2014, it has been decided to adopt the National Glycohemoglobin Standardization Program (NGSP) value, which is used by many countries globally, as the first step toward internationalization. Recently, cardiovascular disease in diabetic patients has been increasing in Japan. Relationships between postprandial hyperglycemia and cardiovascular disease have been noted. Therefore, the correction of postprandial hyperglycemia is one of the important goals of glycemic control to prevent cardiovascular disease. HbA1c or glycated albumin (GA) results from the glycation of hemoglobin or serum albumin and represents 2-month or 2-week glycemia, respectively. In addition, the glycation speed of GA is ten times faster than HbA1c, so GA is likely to reflect the variation in blood glucose and postprandial hyperglycemia in combination with HbA1c and its value. 1,5-anhydroglucitol (AG) is a marker of glycemia-induced glycosuria, since reabsorption of filtered 1,5-AG in the proximal tubule is competitively inhibited by glucose. It is an indicator to identify rapid changes in hyperglycemia. Understanding the characteristics of the

  8. Distribution of fasting plasma glucose and prevalence of impaired fasting glucose, impaired glucose tolerance and type 2 diabetes in the Mexican paediatric population.

    PubMed

    Guerrero-Romero, Fernando; Violante, Rafael; Rodríguez-Morán, Martha

    2009-07-01

    Published data on the distribution of fasting plasma glucose (FPG) in children are scarce. We therefore set out to examine the distribution of FPG and determine the prevalence of impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and type 2 diabetes (T2-DM) in Mexican children aged 6-18 years in a community-based cross-sectional study. A total of 1534 apparently healthy children were randomly enrolled and underwent an oral glucose tolerance test. IFG was defined by an FPG value between >or=100 and <126 mg/dL, IGT by glucose concentration 2-h post-load between >or=140 and <200 mg/dL, and T2-DM by glucose concentration 2-h post-load >or=200 mg/dL. The FPG level at the 75(th) percentile of distribution was 98.0, 100.0 and 99.0 mg/dL for children aged 6-9, 10-14 and 15-18 years, respectively; the 95(th) percentile of FPG was greater than 100 mg/dL for all the age strata. In the population overall, the prevalences of IFG, IGT, and T2-DM were 18.3%, 5.2% and 0.6%, respectively. Among obese children and adolescents, the prevalences of IFG, IGT, IFG + IGT and T2-DM were 19.1%, 5.7%, 2.5% and 1.3%. Our study shows a high prevalence of prediabetes and is the first that reports the distribution of FPG in Mexican children and adolescents.

  9. Plasma FGF21 concentrations, adipose fibroblast growth factor receptor-1 and β-klotho expression decrease with fasting in northern elephant seals.

    PubMed

    Suzuki, Miwa; Lee, Andrew Y; Vázquez-Medina, José Pablo; Viscarra, Jose A; Crocker, Daniel E; Ortiz, Rudy M

    2015-05-15

    Fibroblast growth factor (FGF)-21 is secreted from the liver, pancreas, and adipose in response to prolonged fasting/starvation to facilitate lipid and glucose metabolism. Northern elephant seals naturally fast for several months, maintaining a relatively elevated metabolic rate to satisfy their energetic requirements. Thus, to better understand the impact of prolonged food deprivation on FGF21-associated changes, we analyzed the expression of FGF21, FGF receptor-1 (FGFR1), β-klotho (KLB; a co-activator of FGFR) in adipose, and plasma FGF21, glucose and 3-hydroxybutyrate in fasted elephant seal pups. Expression of FGFR1 and KLB mRNA decreased 98% and 43%, respectively, with fasting duration. While the 80% decrease in mean adipose FGF21 mRNA expression with fasting did not reach statistical significance, it paralleled the 39% decrease in plasma FGF21 concentrations suggesting that FGF21 is suppressed with fasting in elephant seals. Data demonstrate an atypical response of FGF21 to prolonged fasting in a mammal suggesting that FGF21-mediated mechanisms have evolved differentially in elephant seals. Furthermore, the typical fasting-induced, FGF21-mediated actions such as the inhibition of lipolysis in adipose may not be required in elephant seals as part of a naturally adapted mechanism to support their unique metabolic demands during prolonged fasting.

  10. High-efficiency fast scintillators for 'optical' soft x-ray arrays for laboratory plasma diagnostics

    SciTech Connect

    Delgado-Aparicio, L. F.; Stutman, D.; Tritz, K.; Vero, R.; Finkenthal, M.; Suliman, G.; Kaita, R.; Majeski, R.; Stratton, B.; Roquemore, L.; Tarrio, C

    2007-08-20

    Scintillator-based 'optical' soft x-ray (OSXR) arrays have been investigated as a replacement for the conventional silicon (Si)-based diode arrays used for imaging, tomographic reconstruction, magnetohydrodynamics, transport, and turbulence studies in magnetically confined fusion plasma research. An experimental survey among several scintillator candidates was performed, measuring the relative and absolute conversion efficiencies of soft x rays to visible light. Further investigations took into account glass and fiber-optic faceplates (FOPs) as substrates, and a thin aluminum foil(150 nm) to reflect the visible light emitted by the scintillator back to the optical detector.Columnar (crystal growth) thallium-doped cesium iodide (CsI:Tl) deposited on an FOP, was found to be the best candidate for the previously mentioned plasma diagnostics.Its luminescence decay time of the order of?1-10 {mu}s is thus suitable for the 10 {mu}s time resolution required for the development of scintillator-based SXR plasma diagnostics. A prototype eight channel OSXR array using CsI:Tl was designed, built,and compared to an absolute extreme ultraviolet diode counterpart: its operation on the National Spherical Torus Experiment showed a lower level of induced noise relative to the Si-based diode arrays, especially during neutral beam injection heated plasma discharges. The OSXR concept can also be implemented in less harsh environments for basic spectroscopic laboratory plasma diagnostics.

  11. The Effect of LC-MS Data Preprocessing Methods on the Selection of Plasma Biomarkers in Fed vs. Fasted Rats

    PubMed Central

    Gürdeniz, Gözde; Kristensen, Mette; Skov, Thomas; Dragsted, Lars O.

    2012-01-01

    The metabolic composition of plasma is affected by time passed since the last meal and by individual variation in metabolite clearance rates. Rat plasma in fed and fasted states was analyzed with liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF) for an untargeted investigation of these metabolite patterns. The dataset was used to investigate the effect of data preprocessing on biomarker selection using three different softwares, MarkerLynxTM, MZmine, XCMS along with a customized preprocessing method that performs binning of m/z channels followed by summation through retention time. Direct comparison of selected features representing the fed or fasted state showed large differences between the softwares. Many false positive markers were obtained from custom data preprocessing compared with dedicated softwares while MarkerLynxTM provided better coverage of markers. However, marker selection was more reliable with the gap filling (or peak finding) algorithms present in MZmine and XCMS. Further identification of the putative markers revealed that many of the differences between the markers selected were due to variations in features representing adducts or daughter ions of the same metabolites or of compounds from the same chemical subclasses, e.g., lyso-phosphatidylcholines (LPCs) and lyso-phosphatidylethanolamines (LPEs). We conclude that despite considerable differences in the performance of the preprocessing tools we could extract the same biological information by any of them. Carnitine, branched-chain amino acids, LPCs and LPEs were identified by all methods as markers of the fed state whereas acetylcarnitine was abundant during fasting in rats. PMID:24957369

  12. BENCHMARKING FAST-TO-ALFVEN MODE CONVERSION IN A COLD MAGNETOHYDRODYNAMIC PLASMA

    SciTech Connect

    Cally, Paul S.; Hansen, Shelley C. E-mail: shelley.hansen@monash.edu

    2011-09-10

    Alfven waves may be generated via mode conversion from fast magnetoacoustic waves near their reflection level in the solar atmosphere, with implications both for coronal oscillations and for active region helioseismology. In active regions this reflection typically occurs high enough that the Alfven speed a greatly exceeds the sound speed c, well above the a = c level where the fast and slow modes interact. In order to focus on the fundamental characteristics of fast/Alfven conversion, stripped of unnecessary detail, it is therefore useful to freeze out the slow mode by adopting the gravitationally stratified cold magnetohydrodynamic model c {yields} 0. This provides a benchmark for fast-to-Alfven mode conversion in more complex atmospheres. Assuming a uniform inclined magnetic field and an exponential Alfven speed profile with density scale height h, the Alfven conversion coefficient depends on three variables only: the dimensionless transverse-to-the-stratification wavenumber {kappa} = kh, the magnetic field inclination from the stratification direction {theta}, and the polarization angle {phi} of the wavevector relative to the plane containing the stratification and magnetic field directions. We present an extensive exploration of mode conversion in this parameter space and conclude that near-total conversion to outward-propagating Alfven waves typically occurs for small {theta} and large {phi} (80{sup 0}-90{sup 0}), though it is absent entirely when {theta} is exactly zero (vertical field). For wavenumbers of helioseismic interest, the conversion region is broad enough to encompass the whole chromosphere.

  13. Fasting and postprandial remnant-like particle cholesterol concentrations in obese participants are associated with plasma triglycerides, insulin resistance, and body fat distribution.

    PubMed

    van Hees, Anneke M J; Saris, Wim H M; Dallinga-Thie, Geesje M; Hul, Gabby B; Martinez, J Alfredo; Oppert, Jean-Michel; Stich, Vladimir; Astrup, Arne; Arner, Peter; Sørensen, Thorkild I A; Blaak, Ellen E

    2008-12-01

    Elevated plasma concentrations of remnant-like particle cholesterol (RLP-C) are atherogenic. However, factors that determine RLP-C are not fully understood. This study evaluates which factors affect RLP-C in the fasting and postprandial state, using multiple regression analyses in a large cohort of lean and obese participants. All participants (n = 740) underwent a test meal challenge containing 95 energy % (en%) fat (energy content 50% of predicted daily resting metabolic rate). Fasting and postprandial concentrations of circulating metabolites were measured over a 3-h period. Obese participants (n = 613) also participated in a 10-wk weight loss program (-2510 kJ/d), being randomized to either a low-fat or a high-fat diet (20-25 vs. 40-45en% fat). Postprandial RLP-C was associated with fasting RLP-C, waist:hip ratio (WHR), HOMA(IR) (homeostasis model assessment index for insulin resistance) (P < 0.001), and age, independently of BMI and gender [adjusted R(2) (adj. R(2)) = 0.70). These factors were also related to fasting RLP-C (P < 0.010), along with gender and physical activity (adj. R(2) = 0.23). The dietary intervention resulted in significantly lower fasting RLP-C concentrations, independently mediated by weight loss, improvements in HOMA(IR), and the fat content of the prescribed diet. However, after inclusion of plasma triglyceride (TG), HDL-cholesterol, and FFA concentrations in the models, HOMA(IR) and WHR no longer significantly predicted fasting RLP-C, although WHR remained a predictor of postprandial RLP-C (P = 0.002). Plasma TG was strongly associated with both fasting and postprandial RLP-C (P < 0.001). In conclusion, plasma RLP-C concentrations are mainly associated with plasma TG concentrations. Interestingly, the high-fat diet was more effective at decreasing fasting RLP-C concentrations in obese participants than the low-fat diet.

  14. Diabetes mellitus, hemoglobin A1C, and the incidence of total joint arthroplasty infection.

    PubMed

    Iorio, Richard; Williams, Kelly M; Marcantonio, Andrew J; Specht, Lawrence M; Tilzey, John F; Healy, William L

    2012-05-01

    Patients with diabetes have a higher incidence of infection after total joint arthroplasty (TJA) than patients without diabetes. Hemoglobin A1c (HbA1c) levels are a marker for blood glucose control in diabetic patients. A total of 3468 patients underwent 4241 primary or revision total hip arthroplasty or total knee arthroplasty at one institution. Hemoglobin A1c levels were examined to evaluate if there was a correlation between the control of HbA1c and infection after TJA. There were a total of 46 infections (28 deep and 18 superficial [9 cellulitis and 9 operative abscesses]). Twelve (3.43%) occurred in diabetic patients (n = 350; 8.3%) and 34 (0.87%) in nondiabetic patients (n = 3891; 91.7%) (P < .001). There were 9 deep (2.6%) infections in diabetic patients and 19 (0.49%) in nondiabetic patients. In noninfected, diabetic patients, HbA1c level ranged from 4.7% to 15.1% (mean, 6.92%). In infected diabetic patients, HbA1c level ranged from 5.1% to 11.7% (mean, 7.2%) (P < .445). The average HbA1c level in patients with diabetes was 6.93%. Diabetic patients have a significantly higher risk for infection after TJA. Hemoglobin A1c levels are not reliable for predicting the risk of infection after TJA.

  15. Hb A1c Separation by High Performance Liquid Chromatography in Hemoglobinopathies

    PubMed Central

    Chandrashekar, Vani

    2016-01-01

    Hb A1c measurement is subject to interference by hemoglobin traits and this is dependent on the method used for determination. In this paper we studied the difference between Hb A1c measured by HPLC in hemoglobin traits and normal chromatograms. We also studied the correlation of Hb A1c with age. Hemoglobin analysis was carried out by high performance liquid chromatography. Spearman's rank correlation was used to study correlation between A1c levels and age. Mann-Whitney U test was used to study the difference in Hb A1c between patients with normal hemoglobin and hemoglobin traits. A total of 431 patients were studied. There was positive correlation with age in patients with normal chromatograms only. No correlation was seen in Hb E trait or beta thalassemia trait. No significant difference in Hb A1c of patients with normal chromatograms and patients with hemoglobin traits was seen. There is no interference by abnormal hemoglobin in the detection of A1c by high performance liquid chromatography. This method cannot be used for detection of A1c in compound heterozygous and homozygous disorders. PMID:26989559

  16. Cutoff Point of HbA1c for Diagnosis of Diabetes Mellitus in Chinese Individuals

    PubMed Central

    Liu, Ming-Chuan; Li, Xin-Yu; Liu, Xu-Han; Feng, Qiu-Xia; Lu, Lu; Zhu, Zhu; Liu, Ying-Shu; Zhao, Wei; Gao, Zheng-Nan

    2016-01-01

    Background The purpose of the present study was to find the optimal threshold of glycated hemoglobin (HbA1c) for diagnosis of diabetes mellitus in Chinese individuals. Methods A total of 8 391 subjects (including 2 133 men and 6 258 women) aged 40–90 years with gradable retinal photographs were recruited. The relationship between HbA1c and diabetic retinopathy (DR) was examined. Receiver operating characteristic (ROC) curves were used to find the optimal threshold of HbA1c in screening DR and diagnosing diabetes. Results HbA1c values in patients with DR were significantly higher than in those with no DR. The ROC curve for HbA1c had an area under the curve of 0.881 (95%CI 0.857–0.905; P = 0.000). HbA1c at a cutoff of 6.5% had a high sensitivity (80.6%) and specificity (86.9%) for detecting DR. Conclusions HbA1c can be used to diagnose diabetes in a Chinese population, and the optimal HbA1c cutoff point for diagnosis is 6.5%. PMID:27861599

  17. Evaluation of 1,5-Anhydroglucitol, Hemoglobin A1c, and Glucose Levels in Youth and Young Adults with Type 1 Diabetes and Healthy Controls

    PubMed Central

    Mehta, Sanjeev N.; Schwartz, Natalie; Wood, Jamie R.; Svoren, Britta M.; Laffel, Lori M.B.

    2013-01-01

    Background and objective Serum 1,5-anhydroglucitol (1,5-AG) is a marker of hyperglycemic excursions in adults with diabetes and HbA1c <8%. We compared 1,5-AG levels among youth and young adults with and without type 1 diabetes (T1D) and investigated the utility of 1,5-AG in the assessment of glycemic status in pediatric T1D. Methods We compared 1,5-AG, HbA1c, and plasma glucose levels in 138 patients with T1D (duration ≥1 year) and 136 healthy controls, ages 10–30 years. Within each group, we investigated associations between 1,5-AG and clinical characteristics, HbA1c and random plasma glucose. For patients with T1D, 1,5-AG was further analyzed according to HbA1c strata: <8%, 8–9%, and >9%. Results Compared to controls, patients with T1D had higher HbA1c (8.5±1.6% vs. 5.1±0.4%, p<0.0001), lower 1,5-AG (4.0±2.0 vs. 24.7±6.4 μg/mL, p<0.0001), and higher glucose (11.1±5.2 vs. 5.1±0.9 mmol/L, p<0.0001). Males had higher 1,5-AG than females within patients (4.5±2.3 vs. 3.4±1.6 μg/mL, p=0.003) and controls (26.0±6.6 vs. 23.5±6.0 μg/mL, p=0.02). 1,5-AG was not correlated with glucose in either group. 1,5-AG was significantly correlated to HbA1c in patients, but not controls. For patients with HbA1c <8%, 1,5-AG demonstrated the widest range and was not predicted by HbA1c; 1,5-AG levels were narrowly distributed among patients with HbA1c ≥8%. Conclusions Youth and young adults with T1D demonstrate similar 1,5-AG levels which are distinct from controls. 1,5-AG assessment may provide unique information beyond that provided by HbA1c in the mid-term assessment of glycemic control in young patients with T1D and HbA1c <8%. PMID:22060802

  18. Kinetic effects in the conversion of fast waves in pre-heated, low aspect ratio tokamak plasmas

    NASA Astrophysics Data System (ADS)

    Kommoshvili, K.; Cuperman, S.; Bruma, C.

    2003-03-01

    Kinetic effects in the conversion of fast waves to Alfvèn waves and their subsequent deposition in low aspect ratio (spherical) tokamaks (LARTs) have been investigated theoretically. More specifically, we have considered the consequences of incorporation of kinetic effects in the electron parallel (to the ambient magnetic field) dynamics derived by following the drift-tearing mode analysis of Chen et al (Chen L, Rutherford P H and Tang W M 1977 Phys. Rev. Lett. 39 460), and particle-conserving Krook collision operator for the passing electrons involved (Mett R R and Mahajan S M 1992 Phys. Fluids B 4 2885). The perpendicular plasma dynamics is described by a quite general resistive two-fluid (2F) model based dielectric tensor-operator (Cuperman S, Bruma C and Komoshvili K 2002 Solution of the resistive 2F wave equations for Alfvènic modes in spherical tokamak plasmas J. Plasma Phys. accepted for publication). The full-wave electromagnetic equations, formulated in terms of the vector and scalar potentials, have been solved by the aid of an advanced finite elements numerical code (Sewell G 1993 Adv. Eng. Software 17 105). Detailed solutions of the full-wave equations are obtained and compared with those corresponding to a pure resistive 2F model, this, for the illustrative pre-heated START-type device (Sykes 1994). Our results quantitatively confirm the general theory of the conversion of fast waves with subsequent power dissipation for the conditions of spherical tokamaks thus providing the required auxilliary energy source for the succesful operation of LARTs. Moreover, these results indicate the absolute necessity of using a full model for the parallel electron dynamics, i.e. including both kinetic and collisional effects.

  19. Chromium yeast supplementation improves fasting plasma glucose and LDL-cholesterol in streptozotocin-induced diabetic rats.

    PubMed

    Lai, Ming-Hoang; Chen, Ya-Yen; Cheng, Hsing-Hsien

    2006-11-01

    Chromium yeast supplementation has been studied for its ability to improve carbohydrate and lipid abnormalities. There have been some earlier literature-reported studies involving chromium supplementation amongst patients suffering diabetes, but the results would appear to be somewhat varied. Forty male Wistar rats (ten weeks old, 300 g in average body mass) were divided into one of four groups, namely (i) controls; (ii) controls treated with chromium yeast; (iii) diabetic controls; and (iv) diabetic rats treated with chromium yeast. In the present investigation, the effect of a four-week oral administration of chromium yeast (600 microg of Cr/kg body mass/day, by gavage) upon the glucose and lipid metabolism in streptozotocin (STZ)-induced diabetic rats was assessed. Supplemental Cr yeast decreased the fasting blood glucose amongst the STZ-diabetic rats. No significant difference was observed in plasma fructosamine levels of rats treated with chromium yeast compared to control rats. Supplemental Cr yeast did decrease the plasma low-density lipoprotein (LDL)-cholesterol level for the STZ-diabetic rats as compared to controls. We noted no significant effect of chromium supplementation upon plasma high-density lipoprotein (HDL)-cholesterol or triglycerides compared to controls. Treatment with chromium yeast significantly increased the blood and urine chromium levels for both the diabetic and normal rats compared to respective control groups. The results of these studies suggest that Cr yeast decreased the fasting blood glucose and LDL-cholesterol levels in STZ-induced diabetic rats. This raises the possibility that Cr yeast supplementation can be considered to improve carbohydrate and lipid metabolism amongst human patients featuring type 2 diabetes mellitus.

  20. Xanthohumol lowers body weight and fasting plasma glucose in obese male Zucker fa/fa rats.

    PubMed

    Legette, Leecole L; Luna, Arlyn Y Moreno; Reed, Ralph L; Miranda, Cristobal L; Bobe, Gerd; Proteau, Rosita R; Stevens, Jan F

    2013-07-01

    Obesity contributes to increased risk for several chronic diseases including cardiovascular disease and type 2 diabetes. Xanthohumol, a prenylated flavonoid from hops (Humulus lupulus), was tested for efficacy on biomarkers of metabolic syndrome in 4 week old Zucker fa/fa rats, a rodent model of obesity. Rats received daily oral doses of xanthohumol at 0, 1.86, 5.64, and 16.9 mg/kg BW for 6 weeks. All rats were maintained on a high fat (60% kcal) AIN-93G diet for 3 weeks to induce severe obesity followed by a normal AIN-93G (15% kcal fat) diet for the last 3 weeks of the study. Weekly food intake and body weight were recorded. Plasma cholesterol, glucose, insulin, triglyceride, and monocyte chemoattractant protein-1 (MCP-1) levels were assessed using commercial assay kits. Plasma and liver tissue levels of XN and its metabolites were determined by liquid-chromatography tandem mass spectrometry. Plasma and liver tissue levels of xanthohumol were similar between low and medium dose groups and significantly (p<0.05) elevated in the highest dose group. There was a dose-dependent effect on body weight and plasma glucose levels. The highest dose group (n=6) had significantly lower plasma glucose levels compared to the control group (n=6) in male but not female rats. There was also a significant decrease in body weight for male rats in the highest dose group (16.9 mg/kg BW) compared to rats that received no xanthohumol, which was also not seen for female rats. Plasma cholesterol, insulin, triglycerides, and MCP-1 as well as food intake were not affected by treatment. The findings suggest that xanthohumol has beneficial effects on markers of metabolic syndrome.

  1. Quality of HbA1c Measurement in Trinidad and Tobago

    PubMed Central

    Rastogi, Maynika V.; Ladenson, Paul; Goldstein, David E.; Little, Randie R.

    2015-01-01

    Background: Monitoring of HbA1c is the standard of care to assess diabetes control. In Trinidad & Tobago (T&T) there are no existing data on the quality of HbA1c measurement. Our study examined the precision and accuracy of HbA1c testing in T&T. Methods: Sets of 10 samples containing blinded duplicates were shipped to laboratories in T&T. This exercise was repeated 6 months later. Precision and accuracy were estimated for each laboratory/method. Results: T&T methods included immunoassay, capillary electrophoresis, and boronate affinity binding. Most, but not all, laboratories demonstrated acceptable precision and accuracy. Conclusions: Continuous oversight of HbA1c testing (eg, through proficiency testing) in T&T is recommended. These results highlight the lack of oversight of HbA1c testing in some developing countries. PMID:26553021

  2. HbA(1c)--an analyte of increasing importance.

    PubMed

    Higgins, Trefor

    2012-09-01

    Since the incorporation in 1976 of HbA(1c) into a monitoring program of individuals with diabetes, this test has become the gold standard for assessment of glycemic control. Analytical methods have steadily improved in the past two decades, largely through the efforts of the National Glycohemoglobin Standardization program (NGSP). The new definition of HbA(1c) and the introduction of an analytically pure calibrator have increased the possibility for greater improvements in analytical performance. Controversies exist in the reporting of HbA(1c). The use of HbA(1c) has expanded beyond the use solely as a measure of glycemic control into a test for screening and diagnosing diabetes. With improvements in analytical performance, the effects of demographic factors such as age and ethnicity and clinical factors such as iron deficiency have been observed. In this review, the history, formation, analytical methods and parameters that affect HbA(1c) analysis are discussed.

  3. Fast, simple, and sensitive high-performance liquid chromatography method for measuring vitamins A and E in human blood plasma.

    PubMed

    Yuan, Chao; Burgyan, Maria; Bunch, Dustin R; Reineks, Edmunds; Jackson, Raymond; Steinle, Roxanne; Wang, Sihe

    2014-09-01

    Vitamins A and E are fat-soluble vitamins that play important roles in several physiological processes. Monitoring their concentrations is needed to detect deficiency and guide therapy. In this study, we developed a high-performance liquid chromatography method to measure the major forms of vitamin A (retinol) and vitamin E (α-tocopherol and γ-tocopherol) in human blood plasma. Vitamins A and E were extracted with hexane and separated on a reversed-phase column using methanol as the mobile phase. Retinol was detected by ultraviolet absorption, whereas tocopherols were detected by fluorescence emission. The chromatographic cycle time was 4.0 min per sample. The analytical measurement range was 0.03-5.14, 0.32-36.02, and 0.10-9.99 mg/L for retinol, α-tocopherol, and γ-tocopherol, respectively. Intr-aassay and total coefficient of variation were <6.0% for all compounds. This method was traceable to standard reference materials offered by the National Institute of Standards and Technology. Reference intervals were established using plasma samples collected from 51 healthy adult donors and were found to be 0.30-1.20, 6.0-23.0, and 0.3-3.2 mg/L for retinol, α-tocopherol, and γ-tocopherol, respectively. In conclusion, we developed and validated a fast, simple, and sensitive high-performance liquid chromatography method for measuring the major forms of vitamins A and E in human plasma.

  4. Impact of Pre-Plasma on Fast Electron Generation and Transport from Short Pulse High Intensity Lasers

    NASA Astrophysics Data System (ADS)

    Peebles, J.; McGuffey, C.; Krauland, C.; Jarrott, L. C.; Sorokovikova, A.; Qiao, B.; Krasheninnikov, S.; Beg, F. N.; Wei, M. S.; Park, J.; Link, A.; Chen, H.; McLean, H. S.; Wagner, C.; Minello, V.; McCary, E.; Meadows, A.; Spinks, M.; Gaul, E.; Dyer, G.; Hegelich, B. M.; Martinez, M.; Donovan, M.; Ditmire, T.

    2014-10-01

    We present the results and analysis from recent short pulse laser matter experiments using the Texas Petawatt Laser to study the impact of pre-plasma on fast electron generation and transport. The experimental setup consisted of 3 separate beam elements: a main, high intensity, short pulse beam for the interaction, a secondary pulse of equal intensity interacting with a separate thin foil target to generate protons for side-on proton imaging and a third, low intensity, wider beam to generate a varied scale length pre-plasma. The main target consisted of a multilayer planar Al foil with a buried Cu fluor layer. The electron beam was characterized with multiple diagnostics, including several bremsstrahlung spectrometers, magnetic electron spectrometers and Cu-K α imaging. The protons from the secondary target were used to image the fields on the front of the target in the region of laser plasma interaction. Features seen in the interaction region by these protons will be presented along with characteristics of the generated electron beam. This work performed under the auspices of the US DOE under Contracts DE-FOA-0000583 (FES, NNSA).

  5. Fasting modifies Aroclor 1254 impact on plasma cortisol, glucose and lactate responses to a handling disturbance in Arctic charr

    USGS Publications Warehouse

    Jorgensen, E.H.; Vijayan, M.M.; Aluru, N.; Maule, A.G.

    2002-01-01

    Integrated effects of polychlorinated biphenyl (PCB) and nutritional status on responses to handling disturbance were investigated in the Arctic charr (Salvelinus alpinus). The fish were orally contaminated with Aroclor 1254 and held either with or without food for 5 months before they were subjected to a 10-min handling disturbance. Food-deprived fish were given 0, 1, 10 or 100 mg PCB kg-1 and the fed fish 0 or 100 mg PCB kg-1. Plasma cortisol, glucose and lactate levels were measured at 0 (pre-handling), 1, 3, 6 and 23 h after the handling disturbance. Food-deprived control fish had elevated plasma cortisol levels compared with fed fish before handling. These basal cortisol levels were suppressed by PCB in food-deprived fish, and elevated by PCB in fed fish. The immediate cortisol and glucose responses to handling disturbance were suppressed by PCB in a dose-dependent way in food-deprived fish. Although these responses were also lowered by PCB in the fed fish, the effect was much less pronounced than in food-deprived fish. There were only minor effects on plasma lactate responses. Our findings suggest that the stress responses of the Arctic charr are compromised by PCB and that the long-term fasting, typical of high-latitude fish, makes these species particularly sensitive to organochlorines such as PCB. ?? 2002 Elsevier Science Inc. All rights reserved.

  6. Nonlinear dynamics of 3D beams of fast magnetosonic waves propagating in the ionospheric and magnetospheric plasma

    NASA Astrophysics Data System (ADS)

    Belashov, V. Yu.; Belashova, E. S.

    2016-11-01

    On the basis of the model of the three-dimensional (3D) generalized Kadomtsev-Petviashvili equation for magnetic field h = B / B the formation, stability, and dynamics of 3D soliton-like structures, such as the beams of fast magnetosonic (FMS) waves generated in ionospheric and magnetospheric plasma at a low-frequency branch of oscillations when β = 4 πnT/ B 2 ≪ 1 and β > 1, are studied. The study takes into account the highest dispersion correction determined by values of the plasma parameters and the angle θ = ( B, k), which plays a key role in the FMS beam propagation at those angles to the magnetic field that are close to π/2. The stability of multidimensional solutions is studied by an investigation of the Hamiltonian boundness under its deformations on the basis of solving of the corresponding variational problem. The evolution and dynamics of the 3D FMS wave beam are studied by the numerical integration of equations with the use of specially developed methods. The results can be interpreted in terms of the self-focusing phenomenon, as the formation of a stationary beam and the scattering and self-focusing of the solitary beam of FMS waves. These cases were studied with a detailed investigation of all evolutionary stages of the 3D FMS wave beams in the ionospheric and magnetospheric plasma.

  7. Development of an electrochemical immunosensor for the detection of HbA1c in serum.

    PubMed

    Liu, Guozhen; Khor, Sook Mei; Iyengar, Sridhar G; Gooding, J Justin

    2012-02-21

    An electrochemical immuno-biosensor for detecting glycosylated haemoglobin (HbA1c) is reported based on glassy carbon (GC) electrodes with a mixed layer of an oligo(phenylethynylene) molecular wire (MW) and an oligo(ethylene glycol) (OEG). The mixed layer is formed from in situ-generated aryl diazonium cations. To the distal end of the MW, a redox probe 1,1'-di(aminomethyl)ferrocene (FDMA) was attached followed by the covalent attachment of an epitope N-glycosylated pentapeptide (GPP), an analogon to HbA1c, to which an anti-HbA1c monocolonal antibody IgG can selectively bind. HbA1c was detected by a competitive inhibition assay based on the competition for binding to anti-HbA1c IgG antibodies between the analyte in solution, HbA1c, and the surface bound epitope GPP. Exposure of the GPP modified sensing interface to the mixture of anti-HbA1c IgG antibody and HbA1c results in the attenuation of ferrocene electrochemistry due to free antibody binding to the interface. Higher concentrations of analyte led to higher Faradaic currents as less anti-HbA1c IgG is available to bind to the electrode surface. It was observed that there is a good linear relationship between the relative Faradaic current of FDMA and the concentration of HbA1c from 4.5% to 15.1% of total haemoglobin in serum without the need for washing or rinsing steps.

  8. Fast ion generation in the cathode plasma jet of a multipicosecond laser-triggered vacuum discharge

    SciTech Connect

    Moorti, A.; Naik, P. A.; Gupta, P. D.

    2010-03-15

    Ion generation in the cathode plasma jet of a moderate-current ({approx}2.3 kA), low-energy ({<=}20 J) vacuum spark discharge triggered by {approx}27 ps, 10 mJ laser pulses is studied using time of flight technique. Fastest ion velocity and velocity corresponding to the peak of the time of flight signals for Al cathode were measured to be {approx}5.25x10{sup 8} cm/s (energy of {approx}143 keV/u) and {approx}8.1x10{sup 7} cm/s (energy of {approx}3.4 keV/u), respectively. Corresponding velocities in the case of ions generated from laser-produced Al plasma (energy of {approx}550 mJ, intensity of {approx}10{sup 14} W/cm{sup 2}) were found to be much smaller, viz., {approx}1.05x10{sup 8} cm/s (energy of {approx}5.75 keV/u) and {approx}2.63x10{sup 7} cm/s (energy of {approx}0.36 keV/u), respectively. Study shows efficient acceleration of ions in a current-carrying cathode plasma jet of a small-energy multipicosecond laser-triggered spark discharge as compared with that in a high-energy multipicosecond laser-produced plasma plume.

  9. Fast plasma discharge capillary design as a high power throughput soft x-ray emission source

    SciTech Connect

    Wyndham, E. S.; Favre, M.; Valdivia, M. P.; Valenzuela, J. C.; Chuaqui, H.; Bhuyan, H.

    2010-09-15

    We present the experimental details and results from a low energy but high repetition rate compact plasma capillary source for extreme ultraviolet and soft x-ray research and applications. Two lengths of capillary are mounted in two versions of a closely related design. The discharge operates in 1.6 and 3.2 mm inner diameter alumina capillaries of lengths 21 and 36 mm. The use of water both as dielectric and as coolant simplifies the compact low inductance design with nanosecond discharge periods. The stored electrical energy of the discharge is approximately 0.5 J and is provided by directly charging the capacitor plates from an inexpensive insulated-gate bipolar transistor in 1 {mu}s or less. We present characteristic argon spectra from plasma between 30 and 300 A as well as temporally resolved x-ray energy fluence in discrete bands on axis. The spectra also allow the level of ablated wall material to be gauged and associated with useful capillary lifetime according to the chosen configuration and energy storage. The connection between the electron beams associated with the transient hollow cathode mechanism, soft x-ray output, capillary geometry, and capillary lifetime is reported. The role of these e-beams and the plasma as measured on-axis is discussed. The relation of the electron temperature and the ionization stages observed is discussed in the context of some model results of ionization in a non-Maxwellian plasma.

  10. Fast plasma discharge capillary design as a high power throughput soft x-ray emission source.

    PubMed

    Wyndham, E S; Favre, M; Valdivia, M P; Valenzuela, J C; Chuaqui, H; Bhuyan, H

    2010-09-01

    We present the experimental details and results from a low energy but high repetition rate compact plasma capillary source for extreme ultraviolet and soft x-ray research and applications. Two lengths of capillary are mounted in two versions of a closely related design. The discharge operates in 1.6 and 3.2 mm inner diameter alumina capillaries of lengths 21 and 36 mm. The use of water both as dielectric and as coolant simplifies the compact low inductance design with nanosecond discharge periods. The stored electrical energy of the discharge is approximately 0.5 J and is provided by directly charging the capacitor plates from an inexpensive insulated-gate bipolar transistor in 1 μs or less. We present characteristic argon spectra from plasma between 30 and 300 Å as well as temporally resolved x-ray energy fluence in discrete bands on axis. The spectra also allow the level of ablated wall material to be gauged and associated with useful capillary lifetime according to the chosen configuration and energy storage. The connection between the electron beams associated with the transient hollow cathode mechanism, soft x-ray output, capillary geometry, and capillary lifetime is reported. The role of these e-beams and the plasma as measured on-axis is discussed. The relation of the electron temperature and the ionization stages observed is discussed in the context of some model results of ionization in a non-Maxwellian plasma.

  11. Fast and interrupted expansion in cyclic void growth in dusty plasma

    NASA Astrophysics Data System (ADS)

    van de Wetering, F. M. J. H.; Brooimans, R. J. C.; Nijdam, S.; Beckers, J.; Kroesen, G. M. W.

    2015-01-01

    Low-pressure acetylene plasmas are able to spontaneously form dust particles. This will result in a dense cloud of solid particles that is levitated in the plasma. The formed particles can grow up to micrometers. We observed a spontaneous interruption in the expansion of the so-called dust void. A dust void is a macroscopic region in the plasma that is free of nanoparticles. The phenomenon is periodical and reproducible. We refer to the expansion interruption as ‘hiccup’. The expanding void is an environment in which a new cycle of dust particle formation can start. At a certain moment in time, this cycle reaches the (sudden) coagulation phase and as a result the void will temporarily shrink. To substantiate this reasoning, the electron density is determined non-intrusively using microwave cavity resonance spectroscopy. Moreover, video imaging of laser light scattering of the dust particles provides their spatial distribution. The emission intensity of a single argon transition is measured similarly. Our results support the aforementioned hypothesis for what happens during the void hiccup. The void dynamics preceding the hiccup are modeled using a simple analytical model for the two dominant forces (ion drag and electric) working on a nanoparticle in a plasma. The model results qualitatively reproduce the measurements.

  12. Plasma produced by impacts of fast dust particles on a thin film

    NASA Technical Reports Server (NTRS)

    Auer, Siegfried

    1994-01-01

    The thin-film impact plasma detector was pioneered by Berg for detecting small cosmic dust particles and measuring their approximate velocities in a time-of-flight configuration. While Berg's device was highly successful in establishing the flux of interplanetary dust, the accuracy of measuring the velocities of individual particles was a moderate 18 percent in magnitude and 27 degrees in angle. A much greater accuracy of less than or equal to 1 percent in determining the velocity components appears desirable in order to associate a particle with its parent body. In order to meet that need, research was initiated to determine if a thin-film detector can be designed to provide such accurate velocity measurements. Previous laboratory investigations of the impact plasma uncovered two difficulties: (1) solid or liquid spray is ejected from a primary impact crater and strikes neighboring walls where it produces secondary impact craters and plasma clouds; as a result, both quantity and time of detection of the plasma can vary significantly with the experiment configuration. Particles from an accelerator rarely have speeds v greater than or equal to 10-15 km/s, while cosmic dust particles typically impact at v = 10-72 km/s. The purpose of the tests discussed in this paper was to resolve the two difficulties mentioned. That is, the experiment configuration was designed to reduce the contribution of plasma from secondary impacts. In addition, most particles with v less than or equal to 25 km/s and all particles with v less than or equal to 10 km/s were eliminated from the beam.

  13. Ion-induced gamma-ray detection of fast ions escaping from fusion plasmas

    SciTech Connect

    Nishiura, M. Mushiake, T.; Doi, K.; Wada, M.; Taniike, A.; Matsuki, T.; Shimazoe, K.; Yoshino, M.; Nagasaka, T.; Tanaka, T.; Kisaki, M.; Fujimoto, Y.; Fujioka, K.; Yamaoka, H.; Matsumoto, Y.

    2014-11-15

    A 12 × 12 pixel detector has been developed and used in a laboratory experiment for lost fast-ion diagnostics. With gamma rays in the MeV range originating from nuclear reactions {sup 9}Be(α, nγ){sup 12}C, {sup 9}Be(d, nγ){sup 12}C, and {sup 12}C(d, pγ){sup 13}C, a high purity germanium (HPGe) detector measured a fine-energy-resolved spectrum of gamma rays. The HPGe detector enables the survey of background-gamma rays and Doppler-shifted photo peak shapes. In the experiments, the pixel detector produces a gamma-ray image reconstructed from the energy spectrum obtained from total photon counts of irradiation passing through the detector's lead collimator. From gamma-ray image, diagnostics are able to produce an analysis of the fast ion loss onto the first wall in principle.

  14. Interpreting Hemoglobin A1C in Combination With Conventional Risk Factors for Prediction of Cardiovascular Risk

    PubMed Central

    Jarmul, Jamie A.; Pignone, Michael; Pletcher, Mark J.

    2015-01-01

    Background Hemoglobin A1C (HbA1C) is associated with increased risk of cardiovascular events, but its use for prediction of cardiovascular disease (CVD) events in combination with conventional risk factors has not been well defined. Methods and Results To understand the effect of HbA1C on CVD risk in the context of other CVD risk factors, we analyzed HbA1C and other CVD risk factor measurements in 2000 individuals aged 40-79 years old without pre-existing diabetes or cardiovascular disease from the 2011-2012 NHANES survey. The resulting regression model was used to predict the HbA1C distribution based on individual patient characteristics. We then calculated post-test 10-year atherosclerotic cardiovascular disease (ASCVD) risk incorporating the actual versus predicted HbA1C, according to established methods, for a set of example scenarios. Age, gender, race/ethnicity and traditional cardiovascular risk factors were significant predictors of HbA1C in our model, with the expected HbA1C distribution being significantly higher in non-Hispanic black, non-Hispanic Asian and Hispanic individuals than non-Hispanic white/other individuals. Incorporating the expected HbA1C distribution into pretest ASCVD risk has a modest effect on post-test ASCVD risk. In the patient examples we assessed, having an HbA1C < 5.7% reduced post-test risk by 0.4%-2.0% points, whereas having an HbA1C ≥ 6.5% increased post-test risk by 1.0%-2.5% points, depending on the scenario. The post-test risk increase from having an HbA1C ≥ 6.5 % tends to approximate the risk increase from being five years older in age. Conclusions HbA1C has modest effects on predicted ASCVD risk when considered in the context of conventional risk factors. PMID:26349840

  15. Luminol chemiluminescence biosensor for glycated hemoglobin (HbA1c) in human blood samples.

    PubMed

    Ahn, Kwang-Soo; Lee, JungHoon; Park, Jong-Myeon; Choi, Han Nim; Lee, Won-Yong

    2016-01-15

    Luminol chemiluminescence (CL) biosensor based on boronic acid modified gold substrate has been developed for the determination of glycated hemoglobin (HbA1c) in human blood samples. In order to selectively capture HbA1c in sample, carboxy-EG6-undecanethiol was self-assembled on a gold thin-film substrate, followed by covalent coupling of 3-aminophenyl boronic acid (3-APBA). The captured HbA1c containing four iron heme groups plays as a catalyst for luminol CL reaction in the presence of hydrogen peroxide, and thus the luminol CL response is linearly proportional to the amount of HbA1c captured on the biosensor surface. The present biosensor showed linear dynamic range of HbA1c from 2.5% to 17.0%, which well covers the clinically important concentration range. In addition, the present biosensor exhibited negligible response to interfering species such as hemoglobin, fructose, and sorbitol. The present HbA1c biosensor was applied to the determination of HbA1c in human blood samples and the results were well agreed with that obtained with a conventional method.

  16. Interference of the Hope Hemoglobin With Hemoglobin A1c Results.

    PubMed

    Chakraborty, Sutirtha; Chanda, Dalia; Gain, Mithun; Krishnan, Prasad

    2015-01-01

    Hemoglobin A1c (HbA1c) is now considered to be the marker of choice in diagnosis and management of diabetes mellitus, based on the results of certain landmark clinical trials. Herein, we report the case of a 52-year-old ethnic Southeast Asian Indian man with impaired glucose tolerance whose glycated hemoglobin (ie, HbA1c) levels, as measured via Bio-Rad D10 high-performance liquid chromatography (HPLC) and Roche Tina-quant immunoassay were 47.8% and 44.0%, respectively. No variant hemoglobin (Hb) peak was observed via the D10 chromatogram. We assayed the patient specimen on the Sebia MINICAP capillary electrophoresis platform; the HbA1c level was 6.8%, with a large variant Hb peak of 42.0%. This finding suggested the possible presence of the heterozygous Hb Hope, which can result in spuriously elevated HbA1c results on HPLC and turbidimetric immunoassays. Although the capillary electrophoresis system was able to identify the variant, the A1c results should not be considered accurate due to overlapping of the variant and adult Hb peaks on the electrophoretogram reading. Hb Hope is usually clinically silent but can present such analytical challenges. Through this case study, we critically discuss the limitations of various HbA1c assay methods, highlighting the fact that laboratory professionals need to be aware of occurrences of Hb Hope, to help ensure patient safety.

  17. Evaluation and interference study of hemoglobin A1c measured by turbidimetric inhibition immunoassay.

    PubMed

    Chang, J; Hoke, C; Ettinger, B; Penerian, G

    1998-03-01

    The technical performance of the turbidimetric immunoinhibition (TI) assay for hemoglobin (Hb) A1c (Tina-quant Hb A1c, Boehringer Mannheim, Indianapolis, Ind) was evaluated by using the BM/Hitachi 911 analyzer. Intra-assay imprecision was less than 2.7%, and interassay imprecision was less than 2.8% as measured by coefficient of variation. In 93 subjects with diabetes who did not have hemoglobin variants, results of the TI assay for Hb A1c correlated strongly with those obtained by using a high-performance liquid chromatography analyzer (Diamat, BioRad Laboratories, Hercules, Calif). Among 241 subjects who had or did not have hemoglobin variants, the TI assay for Hb A1c correlated strongly with results of affinity chromatography for total glycated hemoglobin (Glyc-Affin GHb, IsoLab, Akron, Ohio). We also studied the effect of various percentages of hemoglobin S, C, E, and F on the accuracy of the TI Hb A1c assay. Only high hemoglobin F percentages caused interference. More than 14 times as many samples can be analyzed per hour by using the TI Hb A1c assay than can be analyzed by using the HPLC assay. For high-volume reference laboratories, using the fully automated TI Hb A1c assay to monitor glycemic control in patients with diabetes may be preferable to using the conventional ion-exchange high-performance liquid chromatography Hb A1c assay because the TI assay measures Hb A1c more accurately in patients with diabetes who have hemoglobin variants, and it requires less time.

  18. SiC detectors for radiation sources characterization and fast plasma diagnostic

    NASA Astrophysics Data System (ADS)

    Cannavò, A.; Torrisi, L.

    2016-09-01

    Semiconductor detectors based on SiC have been investigated to characterize the radiations (photons and particles) emitted from different sources, such as radioactive sources, electron guns, X-ray tubes and laser-generated plasmas. Detectors show high response velocity, low leakage current, high energy gap and high radiation hardness. Their high detection efficiency permits to use the detectors in spectroscopic mode and in time-of-flight (TOF) approach, generally employed to monitor low and high radiation fluxes, respectively. Using the laser start signal, they permit to study the properties of the generated plasma in vacuum by measuring accurately the particle velocity and energy using pulsed lasers at low and high intensities. Possible applications will be reported and discussed.

  19. Ultra-intense, short pulse laser-plasma interactions with applications to the fast ignitor

    SciTech Connect

    Wilks, S.C.; Kruer, W.L.; Young, P.E.; Hammer, J.; Tabak, M.

    1995-04-01

    Due to the advent of chirped pulse amplification (CPA) as an efficient means of creating ultra-high intensity laser light (I > 5{times}10{sup 17} W/cm{sup 2}) in pulses less than a few picoseconds, new ideas for achieving ignition and gain in DT targets with less than 1 megajoule of input energy are currently being pursued. Two types of powerful lasers are employed in this scheme: (1) channeling beams and (2) ignition beams. The current state of laser-plasma interactions relating to this fusion scheme will be discussed. In particular, plasma physics issues in the ultra-intense regime are crucial to the success of this scheme. We compare simulation and experimental results in this highly nonlinear regime.

  20. Acoustic mode driven by fast electrons in TJ-II Electron Cyclotron Resonance plasmas

    NASA Astrophysics Data System (ADS)

    Sun, B. J.; Ochando, M. A.; López-Bruna, D.

    2016-08-01

    Intense harmonic oscillations in radiation signals (δ I/I∼ 5{%}) are commonly observed during Electron Cyclotron Resonance (ECR) heating in TJ-II stellarator plasmas at low line-averaged electron density, 0.15 < \\bar{n}e < 0.6 ×1019 \\text{m}-3 . The frequency agrees with acoustic modes. The poloidal modal structure is compatible with Geodesic Acoustic Modes (GAM) but an n \

  1. Multiplexing slanted spiral microchannels for ultra-fast blood plasma separation.

    PubMed

    Rafeie, Mehdi; Zhang, Jun; Asadnia, Mohsen; Li, Weihua; Warkiani, Majid Ebrahimi

    2016-08-07

    Blood and blood products are critical components of health care. Blood components perform distinct functions in the human body and thus the ability to efficiently fractionate blood into its individual components (i.e., plasma and cellular components) is of utmost importance for therapeutic and diagnostic purposes. Although conventional approaches like centrifugation and membrane filtration for blood processing have been successful in generating relatively pure fractions, they are largely limited by factors such as the required blood sample volume, component purity, clogging, processing time and operation efficiency. In this work, we developed a high-throughput inertial microfluidic system for cell focusing and blood plasma separation from small to large volume blood samples (1-100 mL). Initially, polystyrene beads and blood cells were used to investigate the inertial focusing performance of a single slanted spiral microchannel as a function of particle size, flow rate, and blood cell concentration. Afterwards, blood plasma separation was conducted using an optimised spiral microchannel with relatively large dimensions. It was found that the reject ratio of the slanted spiral channel is close to 100% for blood samples with haematocrit (HCT) values of 0.5% and 1% under an optimal flow rate of 1.5 mL min(-1). Finally, through a unique multiplexing approach, we built a high-throughput system consisting of 16 spiral channels connected together, which can process diluted samples with a total flow rate as high as 24 mL min(-1). The proposed multiplexed system can surmount the shortcomings of previously reported microfluidic systems for plasma separation and cell sorting in terms of throughput, yield and operation efficiency.

  2. Fast Three Dimensional Reconstruction of Magnetohydrodynamic Equilibria in Plasma Confinement Devices

    NASA Astrophysics Data System (ADS)

    Seal, S. K.; Cianciosa, M. R.; Hirshman, S. P.; Wingen, A.; Wilcox, R. S.; Unterberg, E. A.

    2016-10-01

    High-fidelity reconstruction of plasma equilibria in confinement devices like stellarators and tokamaks with external three dimensional (3D) fields is computationally very expensive and routinely requires days, even weeks, to complete using serial approaches. Here, we present the performance results of coupling the 3D plasma reconstruction code, V3FIT, with PARVMEC, the recently developed parallel version of VMEC. We present the parallel design of this coupled software along with a scalability analysis to identify its performance bottlenecks. Dependence of its scalability limits on model parameters is derived. These analyses are supported by scaling studies on over 6,000 processor cores of a Cray XC30 supercomputer. PARVMEC, which dominates the total runtime of the reconstruction procedure, is shown to deliver speedup improvements of over one to two orders of magnitude, depending on whether the equilibrium computations are carried out in a free or fixed boundary mode. The overall speedup of the coupled reconstruction code is shown to deliver over 40X improvement enabling fusion scientists to carry out high-fidelity 3D plasma reconstruction analyses in only a few hours instead of in days/weeks for the first time. This work was supported by the U.S. D.O.E. contract DE-AC05-00OR22725.

  3. Validating predictive models for fast ion profile relaxation in burning plasmas

    DOE PAGES

    Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; ...

    2016-07-22

    The redistribution and potential loss of energetic particles due to MHD modes can limit the performance of fusion plasmas by reducing the plasma heating rate. In this work, we present validation studies of the 1.5D critical gradient model (CGM) for Alfvén eigenmode (AE) induced EP transport in NSTX and DIII-D neutral beam heated plasmas. In previous comparisons with a single DIII-D L-mode case, the CGM model was found to be responsible for 75% of measured AE induced neutron deficit [1]. A fully kinetic HINST is used to compute mode stability for the non-perturbative version of CGM (or nCGM). We have found that AEs show strong local instability drive up tomore » $$\\gamma /\\omega \\sim 20\\%$$ violating assumptions of perturbative approaches used in NOVA-K code. Lastly, we demonstrate that both models agree with each other and both underestimate the neutron deficit measured in DIII-D shot by approximately a factor of 2.« less

  4. Validating predictive models for fast ion profile relaxation in burning plasmas

    SciTech Connect

    Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; Lestz, J. B.; Podesta, M.; Van Zeeland, M. A.; White, R. B.

    2016-07-22

    The redistribution and potential loss of energetic particles due to MHD modes can limit the performance of fusion plasmas by reducing the plasma heating rate. In this work, we present validation studies of the 1.5D critical gradient model (CGM) for Alfvén eigenmode (AE) induced EP transport in NSTX and DIII-D neutral beam heated plasmas. In previous comparisons with a single DIII-D L-mode case, the CGM model was found to be responsible for 75% of measured AE induced neutron deficit [1]. A fully kinetic HINST is used to compute mode stability for the non-perturbative version of CGM (or nCGM). We have found that AEs show strong local instability drive up to $\\gamma /\\omega \\sim 20\\%$ violating assumptions of perturbative approaches used in NOVA-K code. Lastly, we demonstrate that both models agree with each other and both underestimate the neutron deficit measured in DIII-D shot by approximately a factor of 2.

  5. Dietary glycemic index and glycemic load in relation to HbA1c in Japanese obese adults: a cross-sectional analysis of the Saku Control Obesity Program

    PubMed Central

    2012-01-01

    Background Dietary glycemic index or load is thought to play an important role in glucose metabolism. However, few studies have investigated the relation between glycemic index (GI) or load (GL) and glycemia in Asian populations. In this cross-sectional analysis of a randomized controlled trial, the Saku Control Obesity Program, we examined the relation between the baseline GI or GL and glycemia (HbA1c and fasting plasma glucose [FPG] levels), insulin resistance (HOMA-IR), β-cell function (HOMA-β), and other metabolic risk factors (lipid levels, diastolic and systolic blood pressure, and adiposity measures). Methods The participants were 227 obese Japanese women and men. We used multiple linear regression models and logistic regression models to adjust for potential confounding factors such as age, sex, visceral fat area, total energy intake, and physical activity levels. Results After adjustments for potential confounding factors, GI was not associated with HbA1c, but GL was positively associated with HbA1c. For increasing quartiles of GI, the adjusted mean HbA1c were 6.3%, 6.7%, 6.4%, and 6.4% (P for trend = 0.991). For increasing quartiles of GL, the adjusted mean HbA1c were 6.2%, 6.2%, 6.6%, and 6.5% (P for trend = 0.044). In addition, among participants with HbA1c ≥ 7.0%, 20 out of 28 (71%) had a high GL (≥ median); the adjusted odds ratio for HbA1c ≥ 7.0% among participants with higher GL was 3.1 (95% confidence interval [CI] = 1.2 to 8.1) compared to the participants with a lower GL (

  6. Factor Analysis of Changes in Hemoglobin A1c After 12 Months of Sitagliptin Therapy in Patients With Type 2 Diabetes

    PubMed Central

    Yuasa, Shouhei; Sato, Kazuyoshi; Takai, Masahiko; Ishikawa, Masashi; Umezawa, Shinichi; Kubota, Akira; Maeda, Hajime; Kanamori, Akira; Miyakawa, Masaaki; Tanaka, Yasushi; Terauchi, Yasuo; Matsuba, Ikuro

    2016-01-01

    Background Sitagliptin, a dipeptidyl peptidase-4 inhibitor, is an effective oral antidiabetic agent as both monotherapy and when combined with insulin. Data from three observational studies performed in patients with type 2 diabetes receiving sitagliptin therapy in the routine clinical setting were integrated to conduct factor analysis of the changes in hemoglobin A1c (HbA1c), body weight, and estimated glomerular filtration rate (eGFR) over 12 months. Methods Among patients with type 2 diabetes attending medical institutions affiliated with Kanagawa Physicians Association, those using sitagliptin were followed for 1 year. In the ASSET-K and ASSIST-K studies, patients were managed by diabetologists, while they were managed by non-diabetologists in the ATTEST-K study. Patients were not administered insulin in ASSET-K, whereas insulin was administered in ASSIST-K. HbA1c (National Glycohemoglobin Standardization Program), blood glucose (fasting/postprandial), body weight, and renal function (serum creatinine and eGFR) were the efficacy endpoints. Factor analysis was performed by analysis of variance using the magnitude of the change in HbA1c, body weight, and eGFR after 12 months of sitagliptin therapy as response variables, and the study, sex, and age as explanatory variables. Results Of 1,327 patients registered in ASSET-K (diabetologists/without insulin), 1,167 patients in ASSIST-K (diabetologists/with insulin), and 530 patients in ATTEST-K (non-diabetologists), statistical analysis was carried out on 1,074, 854, and 411 patients, respectively. There were significant inter-study differences in patient characteristics (complications, duration of diabetes, and baseline HbA1c), the sitagliptin dose, and the use of other antidiabetic agents. HbA1c decreased significantly in all three studies. According to factor analysis, the magnitude of the change in HbA1c over 12 months showed significant inter-study differences and was also significantly influenced by the age

  7. A fast rise-rate, adjustable-mass-bit gas puff valve for energetic pulsed plasma experiments

    SciTech Connect

    Loebner, Keith T. K. Underwood, Thomas C.; Cappelli, Mark A.

    2015-06-15

    A fast rise-rate, variable mass-bit gas puff valve based on the diamagnetic repulsion principle was designed, built, and experimentally characterized. The ability to hold the pressure rise-rate nearly constant while varying the total overall mass bit was achieved via a movable mechanical restrictor that is accessible while the valve is assembled and pressurized. The rise-rates and mass-bits were measured via piezoelectric pressure transducers for plenum pressures between 10 and 40 psig and restrictor positions of 0.02-1.33 cm from the bottom of the linear restrictor travel. The mass-bits were found to vary linearly with the restrictor position at a given plenum pressure, while rise-rates varied linearly with plenum pressure but exhibited low variation over the range of possible restrictor positions. The ability to change the operating regime of a pulsed coaxial plasma deflagration accelerator by means of altering the valve parameters is demonstrated.

  8. Modeling of fast neutral-beam-generated ion effects on MHD-spectroscopic observations of resistive wall mode stability in DIII-D plasmas

    SciTech Connect

    Turco, F. Hanson, J. M.; Navratil, G. A.; Turnbull, A. D.

    2015-02-15

    Experiments conducted at DIII-D investigate the role of drift kinetic damping and fast neutral beam injection (NBI)-ions in the approach to the no-wall β{sub N} limit. Modelling results show that the drift kinetic effects are significant and necessary to reproduce the measured plasma response at the ideal no-wall limit. Fast neutral-beam ions and rotation play important roles and are crucial to quantitatively match the experiment. In this paper, we report on the model validation of a series of plasmas with increasing β{sub N}, where the plasma stability is probed by active magnetohydrodynamic (MHD) spectroscopy. The response of the plasma to an externally applied field is used to probe the stable side of the resistive wall mode and obtain an indication of the proximity of the equilibrium to an instability limit. We describe the comparison between the measured plasma response and that calculated by means of the drift kinetic MARS-K code [Liu et al., Phys. Plasmas 15, 112503 (2008)], which includes the toroidal rotation, the electron and ion drift-kinetic resonances, and the presence of fast particles for the modelled plasmas. The inclusion of kinetic effects allows the code to reproduce the experimental results within ∼13% for both the amplitude and phase of the plasma response, which is a significant improvement with respect to the undamped MHD-only model. The presence of fast NBI-generated ions is necessary to obtain the low response at the highest β{sub N} levels (∼90% of the ideal no-wall limit). The toroidal rotation has an impact on the results, and a sensitivity study shows that a large variation in the predicted response is caused by the details of the rotation profiles at high β{sub N}.

  9. Addition of strawberries to the usual diet increases postprandial but not fasting non-urate plasma antioxidant activity in healthy subjects.

    PubMed

    Prymont-Przyminska, Anna; Bialasiewicz, Piotr; Zwolinska, Anna; Sarniak, Agata; Wlodarczyk, Anna; Markowski, Jaroslaw; Rutkowski, Krzysztof P; Nowak, Dariusz

    2016-11-01

    Strawberries can augment plasma antioxidant activity, but this may be confounded by selection of methods, time of blood sampling and concomitant dietary restrictions. We examined the effect of strawberry consumption on ferric reducing ability (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (DPPH-test) of native and non-urate plasma in healthy subjects on their usual diet. Eleven subjects consumed strawberries (500 g daily) for 9 days. Fasting and 3-h postprandial plasma and 24-h urine collection were obtained before, during and after strawberry course for FRAP, DPPH-test and polyphenols determination. Fifteen subjects served as a control in respect to plasma antioxidant activity changes and effect of 300 mg of oral ascorbate. First, 5th and 9th strawberry dose increased 3-h postprandial DPPH-test by 17.4, 17.6 and 12.6%, and FRAP by 15.5, 25.6 and 21.4% in comparison to fasting values in non-urate plasma (p<0.05). In native plasma only a trend was observed to higher postprandial values for both tests. Strawberries increased urinary urolithin A and 4-hydroxyhippuric acid whereas plasma polyphenols were stable. No changes of FRAP and DPPH-test were noted in controls and after ascorbate intake. Strawberries transiently increased non-urate plasma antioxidant activity but this cannot be attributed to direct antioxidant effect of polyphenols and ascorbate.

  10. Addition of strawberries to the usual diet increases postprandial but not fasting non-urate plasma antioxidant activity in healthy subjects

    PubMed Central

    Prymont-Przyminska, Anna; Bialasiewicz, Piotr; Zwolinska, Anna; Sarniak, Agata; Wlodarczyk, Anna; Markowski, Jaroslaw; Rutkowski, Krzysztof P.; Nowak, Dariusz

    2016-01-01

    Strawberries can augment plasma antioxidant activity, but this may be confounded by selection of methods, time of blood sampling and concomitant dietary restrictions. We examined the effect of strawberry consumption on ferric reducing ability (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (DPPH-test) of native and non-urate plasma in healthy subjects on their usual diet. Eleven subjects consumed strawberries (500 g daily) for 9 days. Fasting and 3-h postprandial plasma and 24-h urine collection were obtained before, during and after strawberry course for FRAP, DPPH-test and polyphenols determination. Fifteen subjects served as a control in respect to plasma antioxidant activity changes and effect of 300 mg of oral ascorbate. First, 5th and 9th strawberry dose increased 3-h postprandial DPPH-test by 17.4, 17.6 and 12.6%, and FRAP by 15.5, 25.6 and 21.4% in comparison to fasting values in non-urate plasma (p<0.05). In native plasma only a trend was observed to higher postprandial values for both tests. Strawberries increased urinary urolithin A and 4-hydroxyhippuric acid whereas plasma polyphenols were stable. No changes of FRAP and DPPH-test were noted in controls and after ascorbate intake. Strawberries transiently increased non-urate plasma antioxidant activity but this cannot be attributed to direct antioxidant effect of polyphenols and ascorbate. PMID:27895386

  11. [Rapid hemoglobin A1c determination (a new possibility in diabetes care)].

    PubMed

    Jermendy, G; Nádas, J; Farkas, K

    1999-05-30

    To assess the long-term metabolic control, immunochemical method was used for hemoglobin A1c (HbA1c) determinations in diabetic patients. The use of DCA 2000 device (Bayer) resulted in immediate (< 6 min) HbA1c values. The reproducibility of this method was acceptable (within-run coefficients of variations were 3.48% and 4.80%). A close, linear correlation (r = 0.974; p < 0.001; n = 106) between HbA1c-values measured simultaneously by DCA 2000 and DIAMAT (Bio-Rad, method: high pressure liquid chromatography) was observed in diabetic patients. The new immunochemical method proved to be simple and reliable. The immediate (within 6 min) result makes the therapeutic decision easier during the care of diabetic patients.

  12. A history of HbA1c through Clinical Chemistry and Laboratory Medicine.

    PubMed

    Gillery, Philippe

    2013-01-01

    HbA(1c) was discovered in the late 1960s and its use as marker of glycemic control has gradually increased over the course of the last four decades. Recognized as the gold standard of diabetic survey, this parameter was successfully implemented in clinical practice in the 1970s and 1980s and internationally standardized in the 1990s and 2000s. The use of standardized and well-controlled methods, with well-defined performance criteria, has recently opened new directions for HbA(1c) use in patient care, e.g., for diabetes diagnosis. Many reports devoted to HbA1c have been published in Clinical Chemistry and Laboratory Medicine (CCLM) journal. This review reminds the major steps of HbA(1c) history, with a special emphasis on the contribution of CCLM in this field.

  13. 3D Ion and Electron Distribution Function Measurements from the Fast Plasma Investigation on the Magnetospheric Multiscale Mission

    NASA Astrophysics Data System (ADS)

    Giles, B. L.; Pollock, C. J.; Avanov, L. A.; Barrie, A. C.; Burch, J. L.; Chandler, M. O.; Clark, G. B.; Coffey, V. N.; Dickson, C.; Dorelli, J.; Ergun, R. E.; Fuselier, S. A.; Gershman, D. J.; Gliese, U.; Holland, M. P.; Jacques, A. D.; Kreisler, S.; Lavraud, B.; MacDonald, E.; Mauk, B.; Moore, T. E.; Mukai, T.; Nakamura, R.; Paterson, W. R.; Rager, A. C.; Saito, Y.; Salo, C.; Sauvaud, J. A.; Torbert, R. B.; Vinas, A. F.; Yokota, S.

    2015-12-01

    The primary focus of the Magnetospheric Multiscale (MMS) mission, launched in March 2015, is magnetic reconnection and associated processes. Understanding hinges critically on the kinetic physics that allows reconnection to take place. The Fast Plasma Investigation (FPI) provides electron and ion distribution functions at 4.5s cadence and, for select periods of time, at cadences of 30ms for electrons and 150ms for ions. These select time periods are chosen after in situ acquisition based on inspection of the low resolution data. Thus the FPI provides, independent of spacecraft spin rate, the time resolution needed to resolve the small, fast-moving reconnection diffusion regions. The first mission phase focuses on the dayside magnetopause and this presentation is intended to demonstrate the capabilities of FPI to resolve the important spatial scales relevant to the reconnection process. Magnetopause and other boundary crossings will be examined and the phase-space trajectories identified at the tetrahedral satellite locations through analysis of the 3D distribution functions.

  14. Fast Gas Replacement in Plasma Process Chamber by Improving Gas Flow Pattern

    NASA Astrophysics Data System (ADS)

    Morishita, Sadaharu; Goto, Tetsuya; Akutsu, Isao; Ohyama, Kenji; Ito, Takashi; Ohmi, Tadahiro

    2009-01-01

    The precise and high-speed alteration of various gas species is important for realizing precise and well-controlled multiprocesses in a single plasma process chamber with high throughput. The gas replacement times in the replacement of N2 by Ar and that of H2 by Ar are measured in a microwave excited high-density and low electron-temperature plasma process chamber at various working pressures and gas flow rates, incorporating a new gas flow control system, which can avoid overshoot of the gas pressure in the chamber immediately after the valve operation, and a gradational lead screw booster pump, which can maintain excellent pumping capability for various gas species including lightweight gases such as H2 in a wide pressure region from 10-1 to 104 Pa. Furthermore, to control the gas flow pattern in the chamber, upper ceramic shower plates, which have thousands of very fine gas injection holes (numbers of 1200 and 2400) formed with optimized allocation on the plates, are adopted, while the conventional gas supply method in the microwave-excited plasma chamber uses many holes only opened at the sidewall of the chamber (gas ring). It has been confirmed that, in the replacement of N2 by Ar, a short replacement time of approximately 1 s in the cases of 133 and 13.3 Pa and approximately 3 s in the case of 4 Pa can be achieved when the upper shower plate has 2400 holes, while a replacement time longer than approximately 10 s is required for all pressure cases where the gas ring is used. In addition, thanks to the excellent pumping capability of the gradational lead screw booster pump for lightweight gases, it has also been confirmed that the replacement time of H2 by Ar is almost the same as that of N2 by Ar.

  15. Validating predictive models for fast ion profile relaxation in burning plasmas

    NASA Astrophysics Data System (ADS)

    Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; Lestz, J. B.; Podesta, M.; Van Zeeland, M. A.; White, R. B.

    2016-11-01

    The redistribution and potential loss of energetic particles due to MHD modes can limit the performance of fusion plasmas by reducing the plasma heating rate. In this work, we present validation studies of the 1.5D critical gradient model (CGM) for Alfvén eigenmode (AE) induced EP transport in NSTX and DIII-D neutral beam heated plasmas. In previous comparisons with a single DIII-D L-mode case, the CGM model was found to be responsible for 75% of measured AE induced neutron deficit [1]. A fully kinetic HINST is used to compute mode stability for the non-perturbative version of CGM (or nCGM). We have found that AEs show strong local instability drive up to γ /ω ∼ 20% violating assumptions of perturbative approaches used in NOVA-K code. We demonstrate that both models agree with each other and both underestimate the neutron deficit measured in DIII-D shot by approximately a factor of 2. On the other hand in NSTX the application of CGM shows good agreement for the measured flux deficit predictions. We attempt to understand these results with the help of the so-called kick model which is based on the guiding center code ORBIT. The kick model comparison gives important insight into the underlying velocity space dependence of the AE induced EP transport as well as it allows the estimate of the neutron deficit in the presence of the low frequency Alfvénic modes. Within the limitations of used models we infer that there are missing modes in the analysis which could improve the agreement with the experiments.

  16. Whole Blood Donation Affects the Interpretation of Hemoglobin A1c

    PubMed Central

    Lenters-Westra, Erna; de Kort, Wim; Bokhorst, Arlinke G.; Bilo, Henk J. G.; Slingerland, Robbert J.; Vos, Michel J.

    2017-01-01

    Introduction Several factors, including changed dynamics of erythrocyte formation and degradation, can influence the degree of hemoglobin A1c (HbA1c) formation thereby affecting its use in monitoring diabetes. This study determines the influence of whole blood donation on HbA1c in both non-diabetic blood donors and blood donors with type 2 diabetes. Methods In this observational study, 23 non-diabetic blood donors and 21 blood donors with type 2 diabetes donated 475 mL whole blood and were followed prospectively for nine weeks. Each week blood samples were collected and analyzed for changes in HbA1c using three secondary reference measurement procedures. Results Twelve non-diabetic blood donors (52.2%) and 10 (58.8%) blood donors with type 2 diabetes had a significant reduction in HbA1c following blood donation (reduction >-4.28%, P < 0.05). All non-diabetic blood donors with a normal ferritin concentration predonation had a significant reduction in HbA1c. In the non-diabetic group the maximum reduction was -11.9%, in the type 2 diabetes group -12.0%. When eligible to donate again, 52.2% of the non-diabetic blood donors and 41.2% of the blood donors with type 2 diabetes had HbA1c concentrations significantly lower compared to their predonation concentration (reduction >-4.28%, P < 0.05). Conclusion Patients with type 2 diabetes contributing to whole blood donation programs can be at risk of falsely lowered HbA1c. This could lead to a wrong interpretation of their glycemic control by their general practitioner or internist. PMID:28118412

  17. Detection of HbA(1c) by boronate affinity immunoassay using bacterial magnetic particles.

    PubMed

    Tanaka, T; Matsunaga, T

    2001-12-01

    We have developed a boronate affinity immunoassay system using m-aminophenylboronic acid (mAPB) coupling to bacterial magnetic particles (BMPs). Homobifunctional crosslinker, Bis-(succcimidyl)suberate (BS3), was employed for preparation of mAPB-BMPs conjugates (mAPB-BMPs). Quantities of HbA(1c) on mAPB-BMPs were evaluated based on luminescence from alkaline phosphatase-conjugated anti-Hb antibody (ALP-antibody) binding to HbA(1c) on the BMP surface. The binding of HbA(1c) to mAPB-BMPs occurred gradually and was almost completed within 10 mm. The coupling reaction is enhanced due to static electric interaction between the positive charges on HbA(1c) and negative charges on BMPs. The amount of HbA(1c) binding to mAPB-BMPs increased with increasing sodium chloride concentrations in the range of 0-100 mM. However, the amount of Hb binding to mAPB-BMPs also increased in high concentration of sodium chloride. The Hb binding to mAPB-BMPs was detached from mAPB-BMPs when Hb-mAPB-BMPs were washed with low salt buffer. This indicates that Hb is nonspecifically adsorbed onto the surface of mAPB-BMPs in high concentration of sodium chloride. These results suggest that selective separation of HbA(1c) using mAPB-BMPs can be achieved with these conditions. A dose-response curve was obtained between luminescence intensity and HbA(1c) concentration using a fully automated boronate affinity immunoassay. A linear relationship between luminescence intensity and HbA(1c) concentration was obtained in the range of 10-10(4) ng/ml.

  18. Fasting plasma lipids, lipoproteins and apolipoproteins in Nigerian women using combined oral and progestin-only injectable contraceptives.

    PubMed

    Oyelola, O O

    1993-05-01

    Fasting plasma lipid, lipoprotein, and apolipoprotein (apo) profiles were determined in Nigerian women using a low-dose combined oral (Lo-Feminal + Fe) (n = 18), a progestin-only injectable (Depo-Provera) (n = 16) contraceptives and matched controls (n = 18). The mean of plasma total and low-density lipoprotein (LDL) cholesterol, apo B and Lp(a) were significantly higher (p < 0.01) in women using contraceptives than the controls. The mean of total and LDL-cholesterol and apo B were also significantly higher in the oral contraceptive users than those on progestin-only injectables. Furthermore, the mean of cardiovascular disease (CVD) risk indices, total/HDL-cholesterol (p < 0.05) and LDL/HDL-cholesterol (p < 0.01), were significantly higher in women on oral contraceptives than the controls. There were no statistically significant differences between the indices in the women using progestin-only injectables and the controls. Based on this finding, it is concluded that the use of steroidal contraceptives is associated with alterations of lipid and apolipoprotein profiles in Nigerian women and that the use of low-dose combined oral contraceptives may be associated with an increased CVD risk.

  19. Development of a fast EUV movie camera for study of magnetic reconnection in magnetically driven plasma jets

    NASA Astrophysics Data System (ADS)

    Chai, Kil-Byoung; Bellan, Paul

    2012-10-01

    The Caltech MHD driven jet experiment involves a low temperature (˜5 eV) and high density (˜10^21 m-3) plasma that travels at 10's of km/s. During and after formation, magnetic reconnections are observed together with kink and Rayleigh-Taylor instabilities [1]. It has also been observed that there are highly transient EUV emissions when there is magnetic reconnection. The first EUV peak occurs when flux tubes merge during formation and the second one occurs when a Rayleigh-Taylor instability causes the jet to break off from its source electrode. It would be helpful for understanding magnetic reconnection to investigate the spatial and temporal behaviors of these EUV bursts associated with magnetic reconnection. In order to achieve this, we are developing a high speed EUV movie camera. It consists of an Al coated YAG:Ce scintillator, an Au parabolic mirror (or a multilayer coated mirror for a specific EUV wavelength) and a fast framing camera (2x10^8 fps). We tested our system using visible light from the actual plasma jet and obtained image sequence with submicron time resolution.[4pt] [1] A. L. Moser and P. M. Bellan, Nature 482, 379 (2012).

  20. Extremely Nonsinusoidal Emissions and Fast Electron Phenomena from Strong Laser Pulses Obliquely P-Incident on Sharp-Edged Plasmas

    NASA Astrophysics Data System (ADS)

    Johnston, T. W.; Nikolic, L.; Tyshetskiy, Y.; Vidal, F.

    2007-11-01

    High laser harmonic light [1] emerges when the Vulcan petawatt laser's sub-ps laser pulses are obliquely incident on slab targets with extremely low pre-pulse energy. Similar work is in progress with the ALLS 200 TW Ti-Saph laser at INRS EMT. (Pulses are 24 fs at 10 Hz with 10-10 contrast, even without plasma mirrors). 2-D PIC (OSIRIS code at INRS) results on basic mechanism(s) resemble those of Gibbon [2], Naumova et al. [3] and Thaury et al. [4]. The very large and asymmetric electromagnetic ``spikes'' which account for the high harmonic content are produced by extremely concentrated 2D plasma surface currents. The connection between our 2D PIC results (also those in [3] and 1D PIC results [2,4] using the Gibbon-Bourdier moving 1D formalism[2] is also discussed, as are the fast electrons, including some related quasi-steady magnetic fields. [1] B. Dromey et al Nature Phys. Lett., 2, 456-459 (2006) [2] Paul Gibbon, Phys. Rev. Lett. 76, 50 (1996) [3] N. Naumova, et al., Phys. Rev. Lett. 93, 195003 (2004). [4] C. Thaury, et al., Nature Phys. 3, 424 (2007)

  1. What is the Role of HbA1c in Diabetic Hemodialysis Patients?

    PubMed

    Coelho, Silvia

    2016-01-01

    The definition of a good glycemic control in patients with diabetes mellitus on hemodialysis is far from settled. In the general population, hemoglobin A1c is highly correlated with the average glycemia of the last 8-12 weeks. However, in hemodialysis patients, the correlation of hbA1c with glycemia is weaker as it also reflects changes in hemoglobin characteristics and red blood cells half-life. As expected, studies show that the association between HbA1c and outcomes in these patients differ from the general population. Therefore, the value of HbA1c in the treatment of hemodialysis patients has been questioned. Guidelines are generally cautious in their recommendations about possible targets of HbA1c in this population. Indeed, the risk of not treating hyperglycemia should be weighed against the particularly high risk of precipitating hypoglycemia in dialysis patients. In this review, a critical analysis of the current role of HbA1c in the care of hemodialysis patients is presented.

  2. A hemoglobin A1C immunoassay method not affected by carbamylated hemoglobin.

    PubMed

    Rose, A M; Tongate, C; Valdes, R

    1995-01-01

    Hemoglobin A1C (HbA1C) methods based on charge separation of Hb species are subject to interference from carbamylated Hb (carb Hb). Carb Hb adducts are formed via interaction of terminal amino groups of HbA with isocyanic acid, after the spontaneous dissociation of urea to cyanate. It is hypothesized that a new immunoassay method, using a monoclonal antibody that recognizes the N-terminus of the Hb beta-chain and its sugar moiety, should be refractory to cross-reactive interference from carb Hb. To test this hypothesis, Hb was carbamylated in vitro and co-migration of carb Hb assessed with HbA1C using an electrophoretic method. Densitometric scans - post sodium cyanate incubation and electrophoretic separation - showed a 5 to 7 fold elevation of the HbA1C peak only, while HbA1C values obtained using immunoassay were unaffected. Also assessed was carbamylation interference in vivo, and a positive proportional bias with the electrophoretic system (Y) was observed compared to the immunoassay system (X) (y = 1.2x - 0.21 percent). Others have shown that carb Hb may cause a clinically significant false elevation in patient HbA1C values, when methods based on charge separation of Hb species are used. It is our conclusion, however, that while carb Hb may play a role, the differences observed in this study are largely due to calibration.

  3. Development of hemoglobin A1c certified reference material by liquid chromatography isotope dilution mass spectrometry.

    PubMed

    Bi, Jiaming; Wu, Liqing; Yang, Bin; Yang, Yi; Wang, Jing

    2012-04-01

    We report the development of a National Institute of Metrology (NIM) hemoglobin A(1c) (HbA(1c)) certified reference material (CRM). Each CRM unit contains about 10 μL of hemoglobin. Both hemoglobin and glycated hemoglobin were quantitatively determined by high-performance liquid chromatography (HPLC)-isotope dilution mass spectrometry (IDMS) with synthesized VHLTPE and glycated VHLTPE as standards. The mass fraction of synthesized VHLTPE or glycated VHLTPE was also quantitatively determined by HPLC-IDMS with NIM amino acid CRMs as standards. The homogeneity and stability of the CRMs were examined with a commercial HbA(1c) analyzer based on the HPLC principle. Fifteen units were randomly selected for homogeneity examination, and statistical analysis showed there was no inhomogeneity. Examination of the stability showed that the CRM was stable for at least 6 months at -80 °C. Uncertainty components of the balance, amino acid purity, hydrolysis and proteolysis efficiency, method reproducibility, homogeneity, and stability were taken into consideration for uncertainty evaluation. The certified value of NIM HbA(1c) CRM was expressed as the ratio of HbA(1c) to total hemoglobin in moles, and was (9.6 ± 1.9)%. The CRM can be used as a calibration or validation standard for clinical diagnostics. It is expected to improve the comparability for HbA(1c) measurement in China.

  4. Fast, deep record length, time-resolved visible spectroscopy of plasmas using fiber grids

    NASA Astrophysics Data System (ADS)

    Brockington, Samuel; Case, Andrew; Cruz, Edward; Witherspoon, F. Douglas; Horton, Robert; Klauser, Ruth; Hwang, D. Q.

    2016-10-01

    HyperV Technologies is developing a fiber-coupled, deep-record-length, low-light camera head for performing high time resolution spectroscopy on visible emission from plasma events. New solid-state Silicon Photo-Multiplier (SiPM) chips are capable of single photon event detection and high speed data acquisition. By coupling the output of a spectrometer to an imaging fiber bundle connected to a bank of amplified SiPMs, time-resolved spectroscopic imagers of 100 to 1,000 pixels can be constructed. Target pixel performance is 10 Megaframes/sec with record lengths of up to 256,000 frames yielding 25.6 milliseconds of record at10 Megasamples/sec resolution. Pixel resolutions of 8 to 12 bits are pos- sible. Pixel pitch can be refined by using grids of 100 μm to 1000 μm diameter fibers. A prototype 32-pixel spectroscopic imager employing this technique was constructed and successfully tested at the University of California at Davis Compact Toroid Injection Experiment (CTIX) as a full demonstration of the concept. Experimental results will be dis-cussed, along with future plans for the Phase 2 project, and potential applications to plasma experiments . Work supported by USDOE SBIR Grant DE-SC0013801.

  5. Precipitation of fast ion beams from the plasma sheet boundary layer

    NASA Technical Reports Server (NTRS)

    Ashour-Abdalla, M.; Zelenyi, L. M.; Bosqued, J. M.; Kovrazhkin, R. A.

    1992-01-01

    This paper presents a model of precipitated fluxes from the PSBL and CPS. Simulation results and data from Aureol-3 spacecraft indicate the presence of velocity dispersed precipitated ion structures (VDIS) at the poleward edge of the auroral oval. These structures are associated with fast ion beams in the PSBL region of the earth's magnetotail, confirming previous experimental results. The simulations also reveal possible substructuring of the VDIS. The bulk of the PSBL population which is not precipitated is very effectively thermalized and quasi-isotropized after multiple interactions with the magnetotail current layer. After each reflection cycle some part of the distribution is precipitated and forms multiple 'echoes' of VDIS. The CPS distributions occurring as a result of scattering, convection, multiple reflections and Fermi acceleration appear isotropic in the simulation model. This paper portrays the important role of the VDIS auroral region medium for complicated and energetically significant processes occurring in different regions of the distant magnetotail.

  6. Fast magnetic field penetration into a plasma. Ph.D. Thesis

    SciTech Connect

    Armale, R.

    1994-01-01

    Experiments involving propagation of neutralized ion beams across a magnetic field indicate a magnetic field penetration time that is several orders of magnitude faster than the classical, Coulomb collisional or Spitzer, diffusion time. The fast penetration time is of the order of the time scale of the Hall term in Ohm`s law. In magnetohydrodynamics, the Hall current is negligible because the electrons and ions drift together in response to an electric field perpendicular to the magnetic field. For a propagating neutralized ion beam, the ion orbits are completely different from the electron orbits and the Hall current must be considered. Maxwell`s equations and the generalized Ohm`s law are combined in a fluid model to produce a nonlinear diffusion equation for the magnetic field. The equation is linearized, and analytically solved in slab, one dimensional, and cylindrical, two dimensional, geometries. In the slab case, the magnetic field evolution is governed by a diffusion equation with a complex diffusion coefficient. In the cylindrical case, the vector potential is introduced to obtain a lowest order solution of the diffusion equations which are coupled by the Hall term. In both cases, the solution contains whistler wave oscillations and classical diffusion. The whistler waves, which vanish without the Hall term, carry-in the field and determine the penetration time. There is no fast penetration unless there is a component of magnetic field normal to the beam surface which is usually absent for a good conductor. Initially, it is necessary to consider electron inertia and the consequent penetration of the normal component to a depth c/omega(sub p). In addition, it is essential to consider a component of magnetic field parallel to the beam velocity. This component may be absent initially, but is generated by the Hall effect.

  7. Ultra-fast intensified frame images from an electron cyclotron resonance hydrogen plasma at 2.45 GHz: some space distributions of visible and monochromatic emissions.

    PubMed

    Cortázar, O D; Megía-Macías, A; Vizcaíno-de-Julián, A; Tarvainen, O; Komppula, J; Koivisto, H

    2014-02-01

    First results from an ultra-fast frame image acquisition diagnostic coupled to a 2.45 GHz microwave hydrogen discharge are presented. The plasma reactor has been modified to include a transparent doubled shielded quartz window allowing to viewing the full plasma volume. Pictures describing the breakdown process at 1 μs exposure time have been obtained for integrated visible light signal, Balmer-alpha, Balmer-beta lines, and Fulcher-band. Several different plasma emission distributions are reported. The distribution depends on the magnetic field configuration, incident microwave power, and neutral gas pressure.

  8. Hypoglycemia Reduction and Changes in Hemoglobin A1c in the ASPIRE In-Home Study

    PubMed Central

    Weiss, Ram; Garg, Satish K.; Bode, Bruce W.; Bailey, Timothy S.; Ahmann, Andrew J.; Schultz, Kenneth A.; Welsh, John B.

    2015-01-01

    Abstract Background: ASPIRE In-Home randomized 247 subjects with type 1 diabetes to sensor-augmented pump therapy with or without the Threshold Suspend (TS) feature, which interrupts insulin delivery at a preset sensor glucose value. We studied the effects of TS on nocturnal hypoglycemia (NH) in relation to baseline hemoglobin A1c (A1C) and change in A1C during the study. Materials and Methods: NH event rates and mean area under curve (AUC) of NH events were evaluated at different levels of baseline A1C (<7%, 7–8%, and >8%) and at different levels of changes in A1C (less than −0.3% [decreased], −0.3% to 0.3% [stable], and >0.3% [increased]), in the TS Group compared with the Control Group (sensor-augmented pump only). Results: In the TS Group, 27.9% of the NH events were accompanied by a confirmatory blood glucose value, compared with 39.3% in the Control Group. Among subjects with baseline A1C levels of <7% or 7–8%, those in the TS Group had significantly lower NH event rates than those in the Control Group (P=0.001 and P=0.004, respectively). Among subjects with decreased or stable A1C levels, those in the TS Group had significantly lower NH event rates, and the events had lower AUCs (P≤0.001 for each). Among subjects with increased A1C levels, those in the TS Group had NH events with significantly lower AUCs (P<0.001). Conclusions: Use of the TS feature was associated with decreases in the rate and severity (as measured by AUC) of NH events in many subjects, including those with low baseline A1C levels and those whose A1C values decreased during the study period. Use of the TS feature can help protect against hypoglycemia in those wishing to intensify diabetes management to achieve target glucose levels. PMID:26237308

  9. FAST TRACK COMMUNICATION: A variational principle behind the van der Waals picture of strongly coupled plasmas

    NASA Astrophysics Data System (ADS)

    Frusawa, Hiroshi

    2009-02-01

    Various strong coupling theories of the one-component plasma have successfully predicted the thermodynamic and structural properties by separating the Coulomb potential into short- and long-ranged parts in ad hoc ways. Moreover, it has been demonstrated that the density-density correlation function in a mimic system with only short-ranged interactions resembles that of the full Coulomb system, revealing that the van der Waals picture applies to the strongly coupled Coulomb systems. Here we present a variational theory forming the basis of the van der Waals picture. Our approach provides hybrid formulations which combine both the liquid state theory and statistical field theory; essential use is made of the coarse-grained system with only the long-ranged part of Coulomb interactions as a reference system in introducing both the lower bound variational principle and strong coupling expansion.

  10. Application of laser driven fast high density plasma blocks for ion implantation

    NASA Astrophysics Data System (ADS)

    Sari, Amir H.; Osman, F.; Doolan, K. R.; Ghoranneviss, M.; Hora, H.; Höpfl, R.; Benstetter, G.; Hantehzadeh, M. H.

    2005-10-01

    The measurement of very narrow high density plasma blocks of high ion energy from targets irradiated with ps-TW laser pulses based on a new skin depth interaction process is an ideal tool for application of ion implantation in materials, especially of silicon, GaAs, or conducting polymers, for micro-electronics as well as for low cost solar cells. A further application is for ion sources in accelerators with most specifications of many orders of magnitudes advances against classical ion sources. We report on near band gap generation of defects by implantation of ions as measured by optical absorption spectra. A further connection is given for studying the particle beam transforming of n-type semiconductors into p-type and vice versa as known from sub-threshold particle beams. The advantage consists in the use of avoiding aggressive or rare chemical materials when using the beam techniques for industrial applications.

  11. Use of fast scopes to enable Thomson scattering measurement in presence of fluctuating plasma light.

    SciTech Connect

    McLean, H; Moller, J; Hill, D

    2004-04-19

    The addition of inexpensive high-speed oscilloscopes has enabled higher Te Thomson scattering measurements on the SSPX spheromak. Along with signal correlation techniques, the scopes allow new analyses based on the shape of the scattered laser pulse to discriminate against fluctuating background plasma light that often make gated-integrator measurements unreliable. A 1.4 J Nd:YAG laser at 1064 nm is the scattering source. Spatial locations are coupled by viewing optics and fibers to 4-wavelength-channel filter polychrometers. Ratios between the channels determine Te while summations of the channels determine density. Typically, the channel that provides scattered signal at higher Te is contaminated by fluctuating background light. Individual channels are correlated with either a modeled representation of the laser pulse or a noise-free stray light signal to extract channel amplitudes.

  12. Neue biosensorische Prinzipien für die Hämoglobin-A1c Bestimmung

    NASA Astrophysics Data System (ADS)

    Stöllner, Daniela

    2002-06-01

    Hämoglobin-A1c (HbA1c) ist ein Hämoglobin (Hb)-Subtypus, der durch nicht-enzymatische Glykierung des N-terminalen Valinrestes der Hämoglobin-beta-Kette entsteht. Das gemessene Verhältnis von HbA1c zum Gesamt-Hämoglobin (5-20 % bei Diabetikern) repräsentiert den Mittelwert der Blutglucosekonzentration über einen zweimonatigen Zeitraum und stellt zur Beurteilung der diabetischen Stoffwechsellage eine Ergänzung zur Akutkontrolle der Glukosekonzentration dar. Ziel der vorliegenden Arbeit war es, einen amperometrischen Biosensor für die Bestimmung des medizinisch relevanten Parameters HbA1c zu entwickeln. Durch Selektion geeigneter Bioerkennungselemente und deren Immobilisierung unter Erhalt der Bindungsfunktion für die Zielmoleküle Hämoglobin bzw. HbA1c wurden spezifische, hochaffine und regenerationsstabile Sensoroberflächen geschaffen. Für die Entwicklung des HbA1c-Biosensors wurden zwei Konzepte - Enzymsensor und Immunosensor - miteinander verglichen. Die enzymatische Umsetzung von HbA1c erfolgte mit der Fructosylamin Oxidase (FAO) aus Pichia pastoris N 1-1 unter Freisetzung von H2O2, welches sowohl optisch über eine Indikatorreaktion als auch elektrochemisch nach Einschluss der FAO in PVA-SbQ und Fixierung des Immobilisats vor einer H2O2-Elektrode nachgewiesen wurde. Die Kalibration des Enzymsensors mit der HbA1c-Modellsubstanz Fructosyl-Valin ergab Nachweisgrenzen, die ausserhalb des physiologisch relevanten HbA1c-Konzentrationsbereich lagen. Aus der Umsetzung von glykierten Peptiden mit einer nicht HbA1c analogen Aminosäurensequenz, z.B. Fructosyl-Valin-Glycin wurde zudem eine geringe HbA1c-Spezifität abgeleitet. Für den Immunosensor wurden zwei heterogene Immunoassay-Formate unter Verwendung von hochaffinen und spezifischen Antikörpern in Kombination mit Glucose Oxidase (GOD) als Markerenzym zum Nachweis von HbA1c untersucht. Beim indirekt-kompetitiven Immunoassay wurde anstelle des kompletten HbA1c-Moleküls das glykierte Pentapeptid

  13. On The Anomalous Fast Ion Energy Diffusion in Toroidal Plasmas Due to Cavity Modes

    SciTech Connect

    N.N. Gorelenkov, N.J. Fisch and E. Fredrickson

    2010-03-09

    An enormous wave-particle diffusion coefficient along paths suitable for alpha channeling had been deduced in mode converted ion Bernstein wave experiments on Tokamak Fusion Test Reactor (TFTR) the only plausible explanation advanced for such a large diffusion coefficient was the excitation of internal cavity modes which induce particle diffusion along identical diffusion paths, but at much higher rates. Although such a mode was conjectured, it was never observed. However, recent detailed observations of high frequency compressional Alfven eigenmodes (CAEs) on the National Spherical torus Experiment (NSTX) indirectly support the existence of the related conjectured modes on TFTR. The eigenmodes responsible for the high frequency magnetic activity can be identified as CAEs through the polarization of the observed magnetic field oscillations in NSTX and through a comparison with the theoretically derived freuency dispersion relation. Here, we show how these recent observations of high frequency CAEs lend support to this explanation of the long-standing puzzle of anomalous fast ion energy diffusion on TFTR. The support of the conjecure that these internal modes could have caused the remarkable ion energy diffusion on TFTR carries significant and favorable implications for the possibilities in achieving the alpha channeling effect with small injected power in a tokamak reactor.

  14. VIDAS D-dimer: fast quantitative ELISA for measuring D-dimer in plasma.

    PubMed

    Pittet, J L; de Moerloose, P; Reber, G; Durand, C; Villard, C; Piga, N; Rolland, D; Comby, S; Dupuy, G

    1996-03-01

    VIDAS D-dimer (bioMérieux) is a new quantitative ELISA for D-dimer determination designed for the VIDAS automated system. The test contains single-dose, ready-to-use reagents and is completed within 35 min. Quantitative results are obtained from a calibration curve stored in the software of the system and expressed as fibrinogen equivalent units. The two-step capture/tag test relies on two complementary monoclonal anti-D-dimer antibodies, the second one being labeled with alkaline phosphatase. The upper limit of the measuring range is 1000 micrograms/L and the lower detection limit is <50 micrograms/L, which is below the lower limit of the reference interval (68-494 micrograms/L). Reproducibility (CV) within and between runs ranges from 5% to 7%. There is no interference from heparin, bilirubin, hemoglobin, fibrinogen degradation products, or plasma turbidity. Comparison with a conventional ELISA (y) gave good correlation (r= 0.91, n= 579) and comparable results (y= 1.35x - 148, S(y/x)= 750), especially for D-dimer concentrations ranging from 0 to 1000 micrograms/L (y= 1.09x - 10.6, r= 0.88, S(y/x)= 170).

  15. Fast data transmission in dynamic data acquisition system for plasma diagnostics

    NASA Astrophysics Data System (ADS)

    Byszuk, Adrian; Poźniak, Krzysztof; Zabołotny, Wojciech M.; Kasprowicz, Grzegorz; Wojeński, Andrzej; Cieszewski, Radosław; Juszczyk, Bartłomiej; Kolasiński, Piotr; Zienkiewicz, Paweł; Chernyshova, Maryna; Czarski, Tomasz

    2014-11-01

    This paper describes architecture of a new data acquisition system (DAQ) targeted mainly at plasma diagnostic experiments. Modular architecture, in combination with selected hardware components, allows for straightforward reconfiguration of the whole system, both offline and online. Main emphasis will be put into the implementation of data transmission subsystem in said system. One of the biggest advantages of described system is modular architecture with well defined boundaries between main components: analog frontend (AFE), digital backplane and acquisition/control software. Usage of a FPGA chips allows for a high flexibility in design of analog frontends, including ADC <--> FPGA interface. Data transmission between backplane boards and user software was accomplished with the use of industry-standard PCI Express (PCIe) technology. PCIe implementation includes both FPGA firmware and Linux device driver. High flexibility of PCIe connections was accomplished due to use of configurable PCIe switch. Whenever it's possible, described DAQ system tries to make use of standard off-the-shelf (OTF) components, including typical x86 CPU & motherboard (acting as PCIe controller) and cabling.

  16. Fast magnetic reconnection in low-density electron-positron plasmas

    SciTech Connect

    Bessho, Naoki; Bhattacharjee, A.

    2010-10-15

    Two-dimensional particle-in-cell simulations have been performed to study magnetic reconnection in low-density electron-positron plasmas without a guide magnetic field. Impulsive reconnection rates become of the order of unity when the background density is much smaller than 10% of the density in the initial current layer. It is demonstrated that the outflow speed is less than the upstream Alfven speed, and that the time derivative of the density must be taken into account in the definition of the reconnection rate. The reconnection electric fields in the low-density regime become much larger than the ones in the high-density regime, and it is possible to accelerate the particles to high energies more efficiently. The inertial term in the generalized Ohm's law is the most dominant term that supports a large reconnection electric field. An effective collisionless resistivity is produced and tracks the extension of the diffusion region in the late stage of the reconnection dynamics, and significant broadening of the diffusion region is observed. Because of the broadening of the diffusion region, no secondary islands, which have been considered to play a role to limit the diffusion region, are generated during the extension of the diffusion region in the outflow direction.

  17. Method and apparatus for fast laser-pulse detection using gaseous plasmas

    DOEpatents

    McLellan, E.J.; Webb, J.A.

    1981-06-18

    The method and device of the instant invention is a detector of pulsed laser radiation which utilizes the electromotive force generated by the plasma formed when such radiation is focused onto a surface. Measurements are made with a 10.6 ..mu..m CO/sub 2/ laser capable of producing peak intensities of 10/sup 13/ W/cm/sup 2/ when directed through a converging lens. Evacuated detector response to such laser intensity if 1 kV signal peak amplitude and subnanosecond risetimes into a 50 ..cap omega.. load. Detector performance is found to be greatly altered with the introduction of a background gas. For example, with one atmosphere of air, the detector produces prompt signals of the order of 1 V with subnanosecond response for pulse trains lasting 100 ns. With argon, krypton, or zenon at pressures of the order of 10 torr, the detector generates trigger pulses of about 250 V amplitude and 0.2 ns risetimes. Such detectors are quite robust when irradiated with high intensity laser radiation and are useful for qualitative laser beam monitoring.

  18. Method and apparatus for fast laser pulse detection using gaseous plasmas

    DOEpatents

    McLellan, Edward J.; Webb, John A.

    1984-01-01

    The method and device of the instant invention is a detector of pulsed laser radiation which utilizes the electromotive force generated by the plasma formed when such radiation is focused onto a surface (1). Measurements are made with a 10.6 .mu.m CO.sub.2 laser capable of producing peak intensities of 10.sup.13 W/cm.sup.2 when directed through a converging lens (2). Evacuated detector response to such laser intensity is 1 kV signal peak amplitude and subnanosecond risetimes into a 50.OMEGA. load (3). Detector performance is found to be greatly altered with the introduction of a background gas (4). For example, with one atmosphere of air, the detector produces prompt signals of the order of 1 V with subnanosecond response for pulse trains lasting 100 ns. With argon, krypton, or zenon at pressures of the order of 10 torr, the detector generates "trigger pulses" of about 250 V amplitude and 0.2 ns risetimes. Such detectors are quite robust when irradiated with high intensity laser radiation and are useful for qualitative laser beam monitoring.

  19. Stability study for magnetic reagent assaying Hb and HbA1c

    NASA Astrophysics Data System (ADS)

    Hsieh, Wen-Pin; Chieh, J. J.; Yang, C. C.; Yang, S. Y.; Chen, Po-Yu; Huang, Yu-Hao; Hong, Y. W.; Horng, H. E.

    2013-01-01

    Reagents for magnetically labeled immunoassay on human Hb and human HbA1c have been synthesized. The reagents consist of Fe3O4 magnetic particles biofunctionalized with antibodies against Hb and HbA1c. It has been demonstrated that the reagents can be applied to quantitatively detect Hb and HbA1c by using immunomagnetic reduction assay. In addition to characterizing the assay properties, such as the standard curve and the low-detection limit, the stability of reagents is investigated. To do this, the temporal dependence of particle sizes and the bio-activity of reagents are monitored. The results show that the reagents are highly stable when stored at 2-8 °C. This means that the reagents synthesized in this work are promising for practical applications.

  20. The behavior of runaway current in massive gas injection fast shutdown plasmas in J-TEXT

    NASA Astrophysics Data System (ADS)

    Chen, Z. Y.; Huang, D. W.; Luo, Y. H.; Tang, Y.; Dong, Y. B.; Zeng, L.; Tong, R. H.; Wang, S. Y.; Wei, Y. N.; Wang, X. H.; Jian, X.; Li, J. C.; Zhang, X. Q.; Rao, B.; Yan, W.; Ma, T. K.; Hu, Q. M.; Yang, Z. J.; Gao, L.; Ding, Y. H.; Wang, Z. J.; Zhang, M.; Zhuang, G.; Pan, Y.; Jiang, Z. H.; J-TEXT Team

    2016-11-01

    Runaway currents following disruptions have an important effect on the first wall in current tokamaks and will be more severe in next generation tokamaks. The behavior of runaway currents in massive gas injection (MGI) induced disruptions have been investigated in the J-TEXT tokamak. The cold front induced by the gas jet penetrates helically along field lines, preferentially toward the high field side and stops at a location near the q  =  2 surface before the disruption. When the cold front reaches the q  =  2 surface it initiates magnetohydrodynamic activities and results in disruption. It is found that the MGI of He or Ne results in runaway free shutdown in a large range of gas injections. Mixture injection of He and Ar (90% He and 10%Ar) consistently results in runaway free shutdown. A moderate amount of Ar injection could produce significant runaway current. The maximum runaway energy in the runaway plateau is estimated using a simplified model which neglects the drag forces and other energy loss mechanisms. The maximum runaway energy increases with decreasing runaway current. Imaging of the runaway beam using a soft x-ray array during the runaway current plateau indicates that the runaway beam is located in the center of the plasma. Resonant magnetic perturbation (RMP) is applied to reduce the runaway current successfully during the disruption phase in a small scale tokamak, J-TEXT. When the runaway current builds up, the application of RMP cannot decouple the runaway beam due to the lower sensitivity of the energetic runaway electrons to the magnetic perturbation.

  1. Change in fasting plasma glucose and incident type 2 diabetes mellitus: results from a prospective cohort study

    PubMed Central

    Mozaffary, Amirhossein; Asgari, Samaneh; Tohidi, Maryam; Kazempour-Ardebili, Sara; Azizi, Fereidoun; Hadaegh, Farzad

    2016-01-01

    Objective To investigate the association between changes in fasting plasma glucose (FPG) values and incident type 2 diabetes (T2D) in a cohort of the Iranian population. Design Prospective cohort study. Setting This study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS) to investigate the association between change in FPG between baseline examination (1999–2001) and the second visit (2002–2005) with incident T2D. Participants A total of 3981 non-diabetic participants aged ≥20 years. Outcome measure T2D was defined if the participant was using antidiabetic drugs or if FPG was ≥7 mmol/L or if the 2 h post-challenge plasma glucose (2-hPCG) was ≥11.1 mmol/L. Results During a median follow-up of 6.17 years, after the second examination, 288 new cases of T2D were identified. In a multivariate Cox proportional hazard analysis using age as timescale, we presented a simple model including FPG change (HR 1.19, 95% CI 1.07 to 1.33) and baseline waist circumference (WC) (HR 1.004, 95% CI 1.001 to 1.008) with a discriminative power (C-index) of 72%. Furthermore, we showed that the highest quartile of FPG change enhanced the T2D risk to 1.65 (95% CI 1.2 to 2.27) compared with the lowest quartile (p for trend=0.004).The independent risk of FPG change resisted further adjustment with 2-hPCG change. Adding the 2-hPCG change only slightly increased the discriminative power of the model including FPG change and baseline value of WC (0.73% vs 0.72%). After the study population had been limited to those with normal fasting glucose/normal glucose tolerance, FPG change remained an independent predictor (HR 1.57, 95% CI 1.31 to 1.88). Conclusions Two measurements of FPG obtained about 3 years apart can help to identify populations at risk of incident T2D independently of important traditional risk factors and their changes, including 2-hPCG change. PMID:27217283

  2. Runaway electron generation as possible trigger for enhancement of magnetohydrodynamic plasma activity and fast changes in runaway beam behavior

    SciTech Connect

    Pankratov, I. M. E-mail: rjzhou@ipp.ac.cn; Zhou, R. J. E-mail: rjzhou@ipp.ac.cn; Hu, L. Q.

    2015-07-15

    Peculiar phenomena were observed during experiments with runaway electrons: rapid changes in the synchrotron spot and its intensity that coincided with stepwise increases in the electron cyclotron emission (ECE) signal (cyclotron radiation of suprathermal electrons). These phenomena were initially observed in TEXTOR (Tokamak Experiment for Technology Oriented Research), where these events only occurred in the current decay phase or in discharges with thin stable runaway beams at a q = 1 drift surface. These rapid changes in the synchrotron spot were interpreted by the TEXTOR team as a fast pitch angle scattering event. Recently, similar rapid changes in the synchrotron spot and its intensity that coincided with stepwise increases in the non-thermal ECE signal were observed in the EAST (Experimental Advanced Superconducting Tokamak) runaway discharge. Runaway electrons were located around the q = 2 rational magnetic surface (ring-like runaway electron beam). During the EAST runaway discharge, stepwise ECE signal increases coincided with enhanced magnetohydrodynamic (MHD) activity. This behavior was peculiar to this shot. In this paper, we show that these non-thermal ECE step-like jumps were related to the abrupt growth of suprathermal electrons induced by bursting electric fields at reconnection events during this MHD plasma activity. Enhancement of the secondary runaway electron generation also occurred simultaneously. Local changes in the current-density gradient appeared because of local enhancement of the runaway electron generation process. These current-density gradient changes are considered to be a possible trigger for enhancement of the MHD plasma activity and the rapid changes in runaway beam behavior.

  3. Runaway electron generation as possible trigger for enhancement of magnetohydrodynamic plasma activity and fast changes in runaway beam behavior

    NASA Astrophysics Data System (ADS)

    Pankratov, I. M.; Zhou, R. J.; Hu, L. Q.

    2015-07-01

    Peculiar phenomena were observed during experiments with runaway electrons: rapid changes in the synchrotron spot and its intensity that coincided with stepwise increases in the electron cyclotron emission (ECE) signal (cyclotron radiation of suprathermal electrons). These phenomena were initially observed in TEXTOR (Tokamak Experiment for Technology Oriented Research), where these events only occurred in the current decay phase or in discharges with thin stable runaway beams at a q = 1 drift surface. These rapid changes in the synchrotron spot were interpreted by the TEXTOR team as a fast pitch angle scattering event. Recently, similar rapid changes in the synchrotron spot and its intensity that coincided with stepwise increases in the non-thermal ECE signal were observed in the EAST (Experimental Advanced Superconducting Tokamak) runaway discharge. Runaway electrons were located around the q = 2 rational magnetic surface (ring-like runaway electron beam). During the EAST runaway discharge, stepwise ECE signal increases coincided with enhanced magnetohydrodynamic (MHD) activity. This behavior was peculiar to this shot. In this paper, we show that these non-thermal ECE step-like jumps were related to the abrupt growth of suprathermal electrons induced by bursting electric fields at reconnection events during this MHD plasma activity. Enhancement of the secondary runaway electron generation also occurred simultaneously. Local changes in the current-density gradient appeared because of local enhancement of the runaway electron generation process. These current-density gradient changes are considered to be a possible trigger for enhancement of the MHD plasma activity and the rapid changes in runaway beam behavior.

  4. HbA1c as a Diagnostic Test for Diabetes Mellitus – Reviewing the Evidence

    PubMed Central

    Florkowski, Chris

    2013-01-01

    The evidence base in support of HbA1c as a diagnostic test for diabetes mellitus is focused on predicting a clinical outcome, considered to be the pinnacle of the Stockholm Hierarchy applied to reference intervals and clinical decision limits. In the case of diabetes, the major outcome of interest is the long term microvascular complications for which a large body of data has been accumulated, leading to the endorsement of HbA1c for diagnosis in many countries worldwide, with some variations in cut-offs and testing strategies. PMID:24151343

  5. Association between socio-economic status and hemoglobin A1c levels in a Canadian primary care adult population without diabetes

    PubMed Central

    2014-01-01

    Background Hgb A1c levels may be higher in persons without diabetes of lower socio-economic status (SES) but evidence about this association is limited; there is therefore uncertainty about the inclusion of SES in clinical decision support tools informing the provision and frequency of Hgb A1c tests to screen for diabetes. We studied the association between neighborhood-level SES and Hgb A1c in a primary care population without diabetes. Methods This is a retrospective study using data routinely collected in the electronic medical records (EMRs) of forty six community-based family physicians in Toronto, Ontario. We analysed records from 4,870 patients without diabetes, age 45 and over, with at least one clinical encounter between January 1st 2009 and December 31st 2011 and one or more Hgb A1c report present in their chart during that time interval. Residential postal codes were used to assign neighborhood deprivation indices and income levels by quintiles. Covariates included elements known to be associated with an increase in the risk of incident diabetes: age, gender, family history of diabetes, body mass index, blood pressure, LDL cholesterol, HDL cholesterol, triglycerides, and fasting blood glucose. Results The difference in mean Hgb A1c between highest and lowest income quintiles was -0.04% (p = 0.005, 95% CI -0.07% to -0.01%), and between least deprived and most deprived was -0.05% (p = 0.003, 95% CI -0.09% to -0.02%) for material deprivation and 0.02% (p = 0.2, 95% CI -0.06% to 0.01%) for social deprivation. After adjustment for covariates, a marginally statistically significant difference in Hgb A1c between highest and lowest SES quintile (p = 0.04) remained in the material deprivation model, but not in the other models. Conclusions We found a small inverse relationship between Hgb A1c and the material aspects of SES; this was largely attenuated once we adjusted for diabetes risk factors, indicating that an independent contribution of SES

  6. Intermittent fasting modulation of the diabetic syndrome in sand rats. III. Post-mortem investigations.

    PubMed

    Belkacemi, Louiza; Selselet-Attou, Ghalem; Bulur, Nurdan; Louchami, Karim; Sener, Abdullah; Malaisse, Willy J

    2011-01-01

    The present report concerns several post-mortem variables examined in sand rats that were either maintained on a vegetal diet (control animals) or exposed first during a 20-day transition period to a mixed diet consisting of a fixed amount of a hypercaloric food and decreasing amounts of the vegetal food and then to a 30-day experimental period of exposure to the hypercaloric food. During the latter period, all animals were either given free access to food or fasting daily for 15 h, i.e. from 5.00 p.m. to 8.00 a.m. The body weight, liver wet weight, pancreas wet weight, plasma glucose and haemoglobin A1c concentration, plasma insulin concentration, insulinogenic index, insulin resistance HOMA, plasma cholesterol and triglyceride concentration, liver triglyceride and phospholipid content were all measured. Pancreatic islet (insulin, GLUT2) and liver (lipid droplets) histology were also examined. The main findings consisted in a lower body weight of fasting than non-fasting animals, a higher liver weight in non-diabetic and diabetic rats than in control non-fasting (but not so in fasting) animals, a decrease of pancreas weight in non-diabetic and diabetic as distinct from control animals, a fasting-induced decrease in plasma glucose, plasma insulin and insulin resistance HOMA, plasma cholesterol and triglyceride concentration and triglyceride liver content.

  7. Evaluating the transferability of 15 European-derived fasting plasma glucose SNPs in Mexican children and adolescents

    PubMed Central

    Langlois, Christine; Abadi, Arkan; Peralta-Romero, Jesus; Alyass, Akram; Suarez, Fernando; Gomez-Zamudio, Jaime; Burguete-Garcia, Ana I.; Yazdi, Fereshteh T.; Cruz, Miguel; Meyre, David

    2016-01-01

    Genome wide association studies (GWAS) have identified single-nucleotide polymorphisms (SNPs) that are associated with fasting plasma glucose (FPG) in adult European populations. The contribution of these SNPs to FPG in non-Europeans and children is unclear. We studied the association of 15 GWAS SNPs and a genotype score (GS) with FPG and 7 metabolic traits in 1,421 Mexican children and adolescents from Mexico City. Genotyping of the 15 SNPs was performed using TaqMan Open Array. We used multivariate linear regression models adjusted for age, sex, body mass index standard deviation score, and recruitment center. We identified significant associations between 3 SNPs (G6PC2 (rs560887), GCKR (rs1260326), MTNR1B (rs10830963)), the GS and FPG level. The FPG risk alleles of 11 out of the 15 SNPs (73.3%) displayed significant or non-significant beta values for FPG directionally consistent with those reported in adult European GWAS. The risk allele frequencies for 11 of 15 (73.3%) SNPs differed significantly in Mexican children and adolescents compared to European adults from the 1000G Project, but no significant enrichment in FPG risk alleles was observed in the Mexican population. Our data support a partial transferability of European GWAS FPG association signals in children and adolescents from the admixed Mexican population. PMID:27782183

  8. A variant near MTNR1B is associated with increased fasting plasma glucose levels and type 2 diabetes risk.

    PubMed

    Bouatia-Naji, Nabila; Bonnefond, Amélie; Cavalcanti-Proença, Christine; Sparsø, Thomas; Holmkvist, Johan; Marchand, Marion; Delplanque, Jérôme; Lobbens, Stéphane; Rocheleau, Ghislain; Durand, Emmanuelle; De Graeve, Franck; Chèvre, Jean-Claude; Borch-Johnsen, Knut; Hartikainen, Anna-Liisa; Ruokonen, Aimo; Tichet, Jean; Marre, Michel; Weill, Jacques; Heude, Barbara; Tauber, Maithé; Lemaire, Katleen; Schuit, Frans; Elliott, Paul; Jørgensen, Torben; Charpentier, Guillaume; Hadjadj, Samy; Cauchi, Stéphane; Vaxillaire, Martine; Sladek, Robert; Visvikis-Siest, Sophie; Balkau, Beverley; Lévy-Marchal, Claire; Pattou, François; Meyre, David; Blakemore, Alexandra I F; Jarvelin, Marjo-Riita; Walley, Andrew J; Hansen, Torben; Dina, Christian; Pedersen, Oluf; Froguel, Philippe

    2009-01-01

    In genome-wide association (GWA) data from 2,151 nondiabetic French subjects, we identified rs1387153, near MTNR1B (which encodes the melatonin receptor 2 (MT2)), as a modulator of fasting plasma glucose (FPG; P = 1.3 x 10(-7)). In European populations, the rs1387153 T allele is associated with increased FPG (beta = 0.06 mmol/l, P = 7.6 x 10(-29), N = 16,094), type 2 diabetes (T2D) risk (odds ratio (OR) = 1.15, 95% CI = 1.08-1.22, P = 6.3 x 10(-5), cases N = 6,332) and risk of developing hyperglycemia or diabetes over a 9-year period (hazard ratio (HR) = 1.20, 95% CI = 1.06-1.36, P = 0.005, incident cases N = 515). RT-PCR analyses confirm the presence of MT2 transcripts in neural tissues and show MT2 expression in human pancreatic islets and beta cells. Our data suggest a possible link between circadian rhythm regulation and glucose homeostasis through the melatonin signaling pathway.

  9. Is hemoglobin A1c level effective in predicting the prognosis of Fournier gangrene?

    PubMed Central

    Sen, Haluk; Bayrak, Omer; Erturhan, Sakip; Borazan, Ersin; Koc, Mustafa Nihat

    2016-01-01

    Objectives: To evaluate the effect of immune failure and/or diabetes mellitus (DM) association on the mortality and morbidity of the Fournier's Gangrene (FG), and interrelatedly, the usability of HbA1c level in the prediction of prognosis. Materials and Methods: The data of 38 patients with the diagnosis of FG were investigated retrospectively. The patients were divided into two groups as patients with DM (Group 1, n = 18) and non-diabetics (Group 2, n = 20). The patients in group 1 were also divided into two subgroups as patients with HbA1c value ≥7 (Group 1a) and HbA1c value <7 (Group 1b). Results: The mean age of all 38 male patients was 66.3 ± 6.4 years. The initial symptoms were scrotal rash and swelling (n = 20, 52.6%), high fever (>38°C) (n = 22, 57.8%), purulent discharge from genital or perineal areas (n = 13, 34.2%), skin bruises (n = 11, 28.9%) and general state disorder in five patients that were admitted from day care center (13.1%). DM, as the most often comorbid disease, was detected in 18 patients (47.3%). Six patients (15.7%) were deceased during the follow-up period. Conclusion: In the present study, the researchers determined that diabetic patients with HbA1c level of 7 or higher had worse prognosis, and increased mortality. PMID:27453658

  10. Evaluation of observable phase space by fast ion loss detector by calculating particle orbits in consideration of plasma facing components and three dimensional magnetic field.

    PubMed

    Shinohara, Kouji; Kim, Junghee; Kim, Jun Young; Rhee, Tongnyeol

    2016-11-01

    The orbits of lost ions can be calculated from the information obtained by a fast ion loss detector (FILD). The orbits suggest a source of the lost fast ions in a phase space. However, it is not obvious whether an observable set of orbits, or phase space, of a FILD appropriately covers the region of interest to be investigated since the observable phase space can be affected by plasma facing components (PFCs) and a magnetic configuration. A tool has been developed to evaluate the observable phase space of FILD diagnostic by calculating particle orbits by taking the PFCs and 3D magnetic field into account.

  11. Use of soft x-ray diagnostic on the COMPASS tokamak for investigations of sawteeth crash neighborhood and of plasma position using fast inversion methodsa)

    NASA Astrophysics Data System (ADS)

    Imrisek, M.; Weinzettl, V.; Mlynar, J.; Odstrcil, T.; Odstrcil, M.; Ficker, O.; Pinzon, J. R.; Ehrlacher, C.; Panek, R.; Hron, M.

    2014-11-01

    The soft x-ray diagnostic is suitable for monitoring plasma activity in the tokamak core, e.g., sawtooth instability. Moreover, spatially resolved measurements can provide information about plasma position and shape, which can supplement magnetic measurements. In this contribution, fast algorithms with the potential for a real-time use are tested on the data from the COMPASS tokamak. In addition, the soft x-ray data are compared with data from other diagnostics in order to discuss possible connection between sawtooth instability on one side and the transition to higher confinement mode, edge localized modes and productions of runaway electrons on the other side.

  12. Use of soft x-ray diagnostic on the COMPASS tokamak for investigations of sawteeth crash neighborhood and of plasma position using fast inversion methods.

    PubMed

    Imrisek, M; Weinzettl, V; Mlynar, J; Odstrcil, T; Odstrcil, M; Ficker, O; Pinzon, J R; Ehrlacher, C; Panek, R; Hron, M

    2014-11-01

    The soft x-ray diagnostic is suitable for monitoring plasma activity in the tokamak core, e.g., sawtooth instability. Moreover, spatially resolved measurements can provide information about plasma position and shape, which can supplement magnetic measurements. In this contribution, fast algorithms with the potential for a real-time use are tested on the data from the COMPASS tokamak. In addition, the soft x-ray data are compared with data from other diagnostics in order to discuss possible connection between sawtooth instability on one side and the transition to higher confinement mode, edge localized modes and productions of runaway electrons on the other side.

  13. Influence of the physiological variability of fasted gastric pH and tablet retention time on the variability of in vitro dissolution and simulated plasma profiles.

    PubMed

    Kovačič, Nataša Nagelj; Pišlar, Mitja; Ilić, Ilija; Mrhar, Aleš; Bogataj, Marija

    2014-10-01

    The aim of the present study was to show that the physiological variability of fasted gastric pH and tablet gastric retention time contributes to the overall variability of simulated plasma profiles of diclofenac. Those two parameters were implemented into dissolution study and plasma profiles were simulated under assumptions that in vitro dissolution well represents that occurring in vivo, and that absorption profiles are identical to dissolution profiles, as diclofenac is a highly permeable drug. Dissolution experiments were performed using USP 2 apparatus and two consecutive dissolution media, namely, an acidic medium of various pH (ranging from 1-3), where tablets were kept for a certain time (10-200 min), and phosphate buffer (pH 6.8). It was shown that the acid pH value and acid retention time of tablets affect in vitro drug release, and consequently also influence the simulated plasma profiles. Lower acid pH resulted in lower plasma peaks at each studied acid retention time. Longer acid retention time caused lower plasma concentrations at lower acid pH values, whereas at pH 3 higher plasma concentrations were noted. Additionally, it was demonstrated that the variability of both parameters represents an important contribution to the overall variability of plasma profiles.

  14. Genetic Variant in HK1 Is Associated With a Proanemic State and A1C but Not Other Glycemic Control–Related Traits

    PubMed Central

    Bonnefond, Amélie; Vaxillaire, Martine; Labrune, Yann; Lecoeur, Cécile; Chèvre, Jean-Claude; Bouatia-Naji, Nabila; Cauchi, Stéphane; Balkau, Beverley; Marre, Michel; Tichet, Jean; Riveline, Jean-Pierre; Hadjadj, Samy; Gallois, Yves; Czernichow, Sébastien; Hercberg, Serge; Kaakinen, Marika; Wiesner, Susanne; Charpentier, Guillaume; Lévy-Marchal, Claire; Elliott, Paul; Jarvelin, Marjo-Riitta; Horber, Fritz; Dina, Christian; Pedersen, Oluf; Sladek, Robert; Meyre, David; Froguel, Philippe

    2009-01-01

    OBJECTIVE A1C is widely considered the gold standard for monitoring effective blood glucose levels. Recently, a genome-wide association study reported an association between A1C and rs7072268 within HK1 (encoding hexokinase 1), which catalyzes the first step of glycolysis. HK1 deficiency in erythrocytes (red blood cells [RBCs]) causes severe nonspherocytic hemolytic anemia in both humans and mice. RESEARCH DESIGN AND METHODS The contribution of rs7072268 to A1C and the RBC-related traits was assessed in 6,953 nondiabetic European participants. We additionally analyzed the association with hematologic traits in 5,229 nondiabetic European individuals (in whom A1C was not measured) and 1,924 diabetic patients. Glucose control–related markers other than A1C were analyzed in 18,694 nondiabetic European individuals. A type 2 diabetes case-control study included 7,447 French diabetic patients. RESULTS Our study confirms a strong association between the rs7072268–T allele and increased A1C (β = 0.029%; P = 2.22 × 10−7). Surprisingly, despite adequate study power, rs7072268 showed no association with any other markers of glucose control (fasting- and 2-h post-OGTT–related parameters, n = 18,694). In contrast, rs7072268–T allele decreases hemoglobin levels (n = 13,416; β = −0.054 g/dl; P = 3.74 × 10−6) and hematocrit (n = 11,492; β = −0.13%; P = 2.26 × 10−4), suggesting a proanemic effect. The T allele also increases risk for anemia (836 cases; odds ratio 1.13; P = 0.018). CONCLUSIONS HK1 variation, although strongly associated with A1C, does not seem to be involved in blood glucose control. Since HK1 rs7072268 is associated with reduced hemoglobin levels and favors anemia, we propose that HK1 may influence A1C levels through its anemic effect or its effect on glucose metabolism in RBCs. These findings may have implications for type 2 diabetes diagnosis and clinical management because anemia is a frequent complication of the diabetes state. PMID

  15. Local Population Characteristics and Hemoglobin A1c Testing Rates among Diabetic Medicare Beneficiaries

    PubMed Central

    Yasaitis, Laura C.; Bubolz, Thomas; Skinner, Jonathan S.; Chandra, Amitabh

    2014-01-01

    Background Proposed payment reforms in the US healthcare system would hold providers accountable for the care delivered to an assigned patient population. Annual hemoglobin A1c (HbA1c) tests are recommended for all diabetics, but some patient populations may face barriers to high quality healthcare that are beyond providers' control. The magnitude of fine-grained variations in care for diabetic Medicare beneficiaries, and their associations with local population characteristics, are unknown. Methods HbA1c tests were recorded for 480,745 diabetic Medicare beneficiaries. Spatial analysis was used to create ZIP code-level estimated testing rates. Associations of testing rates with local population characteristics that are outside the control of providers – population density, the percent African American, with less than a high school education, or living in poverty – were assessed. Results In 2009, 83.3% of diabetic Medicare beneficiaries received HbA1c tests. Estimated ZIP code-level rates ranged from 71.0% in the lowest decile to 93.1% in the highest. With each 10% increase in the percent of the population that was African American, associated HbA1c testing rates were 0.24% lower (95% CI −0.32–−0.17); for identical increases in the percent with less than a high school education or the percent living in poverty, testing rates were 0.70% lower (−0.95–−0.46) and 1.6% lower (−1.8–−1.4), respectively. Testing rates were lowest in the least and most densely populated ZIP codes. Population characteristics explained 5% of testing rate variations. Conclusions HbA1c testing rates are associated with population characteristics, but these characteristics fail to explain the vast majority of variations. Consequently, even complete risk-adjustment may have little impact on some process of care quality measures; much of the ZIP code-related variations in testing rates likely result from provider-based differences and idiosyncratic local factors not related to

  16. Decreased expression of adipose CD36 and FATP1 are associated with increased plasma non-esterified fatty acids during prolonged fasting in northern elephant seal pups (Mirounga angustirostris).

    PubMed

    Viscarra, Jose Abraham; Vázquez-Medina, José Pablo; Rodriguez, Ruben; Champagne, Cory D; Adams, Sean H; Crocker, Daniel E; Ortiz, Rudy M

    2012-07-15

    The northern elephant seal pup (Mirounga angustirostris) undergoes a 2-3 month post-weaning fast, during which it depends primarily on the oxidation of fatty acids to meet its energetic demands. The concentration of non-esterified fatty acids (NEFAs) increases and is associated with the development of insulin resistance in late-fasted pups. Furthermore, plasma NEFA concentrations respond differentially to an intravenous glucose tolerance test (ivGTT) depending on fasting duration, suggesting that the effects of glucose on lipid metabolism are altered. However, elucidation of the lipolytic mechanisms including lipase activity during prolonged fasting in mammals is scarce. To assess the impact of fasting and glucose on the regulation of lipid metabolism, adipose tissue and plasma samples were collected before and after ivGTTs performed on early (2 weeks, N=5) and late (6-8 weeks; N=8) fasted pups. Glucose administration increased plasma triglycerides and NEFA concentrations in late-fasted seals, but not plasma glycerol. Fasting decreased basal adipose lipase activity by 50%. Fasting also increased plasma lipase activity twofold and decreased the expressions of CD36, FAS, FATP1 and PEPCK-C by 22-43% in adipose tissue. Plasma acylcarnitine profiling indicated that late-fasted seals display higher incomplete LCFA β-oxidation. Results suggest that long-term fasting induces shifts in the regulation of lipolysis and lipid metabolism associated with the onset of insulin resistance in northern elephant seal pups. Delineation of the mechanisms responsible for this shift in regulation during fasting can contribute to a more thorough understanding of the changes in lipid metabolism associated with dyslipidemia and insulin resistance in mammals.

  17. [HbA1c is not enough in screening for impaired glucose metabolism. Glucose tolerance tests are also needed, as shown in Swedish prospective epidemiological study].

    PubMed

    Hellgren, Margareta; Daka, Bledar; Larsson, Charlotte

    2015-09-29

    An HbA1c threshold of ≥ 42 mmol/mol has been proposed to diagnose prediabetes. The sensitivity, specificity and positive predictive value of the proposed threshold for detection of individuals with prediabetes was examined in a study of 573 randomly selected individuals from Vara and Skövde. In addition, the utility of the FINDRISC questionnaire and of a fasting glucose test in combination with three short questions concerning BMI, heredity for type 2 diabetes and known hypertension was examined. Results from an oral glucose tolerance test were used as reference. The sensitivity of HbA1c and FINDRISC to detect individuals with IGT was 16 and 26 per cent respectively. Questions regarding BMI, heredity and hypertension together with a fasting glucose test yielded a sensitivity of 50%, but a lower specificity and positive predictive value. We conclude that HbA1c inefficiently detected individuals with impaired glucose tolerance and that oral glucose tolerance tests can still preferably be recommended.

  18. Fasting and nutrient-stimulated plasma peptide-YY levels are elevated in critical illness and associated with feed intolerance: an observational, controlled study

    PubMed Central

    Nguyen, Nam Q; Fraser, Robert JL; Chapman, Marianne; Bryant, Laura K; Wishart, Judith; Holloway, Richard H; Horowitz, Michael

    2006-01-01

    Introduction Delayed gastric emptying and feed intolerance occur frequently in the critically ill. In these patients, gastric motor responses to nutrients are disturbed. Peptide YY (PYY) slows gastric emptying. The aim of this study was to determine fasting and nutrient-stimulated plasma PYY concentrations and their relationship to cholecystokinin (CCK) in critically ill patients. Methods Studies were performed in 19 unselected mechanically ventilated critically ill patients (12 males; 48 ± 7 years old) in a randomised, single-blind fashion. Subjects received a 60-minute duodenal infusion of Ensure® at either 1 or 2 kcal/minute. Blood samples were collected at baseline and at 20, 40, 60, and 180 minutes following commencement of the nutrient infusion for the measurement of plasma PYY and CCK concentrations (using radioimmunoassay). Patient data were compared to 24 healthy subjects (17 males; 43 ± 2 years old). Results Fasting PYY concentration was higher in patients (P < 0.05), particularly in those with feed intolerance (P < 0.05). Plasma PYY concentrations were higher in patients during nutrient infusion (area under the curve [AUC] at 1 kcal/minute: 2,265 ± 718 versus 1,125 ± 138 pmol/l.min, P < 0.05; at 2 kcal/minute: 2,276 ± 303 versus 1,378 ± 210 pmol/l.min, P = 0.01) compared to healthy subjects. The magnitude of PYY elevation was greater in patients during the 1 kcal/minute infusion (AUC: 441 ± 153 versus 186 ± 58 pmol/l.min, P < 0.05), but not the 2 kcal/minute infusion. Fasting and nutrient-stimulated plasma CCK concentrations were higher in patients (P < 0.05). There was a relationship between plasma PYY and CCK concentrations during fasting (r = 0.52, P < 0.05) and nutrient infusion (r = 0.98, P < 0.0001). Conclusion In critical illness, both fasting and nutrient-stimulated plasma PYY concentrations are elevated, particularly in patients with feed intolerance, in conjunction with increased CCK concentrations. PMID:17173662

  19. The association of hs-CRP with fasting and postprandial plasma lipids in patients with type 2 diabetes is disrupted by dietary monounsaturated fatty acids.

    PubMed

    Bozzetto, L; De Natale, C; Di Capua, L; Della Corte, G; Patti, L; Maione, S; Riccardi, G; Rivellese, A A; Annuzzi, G

    2013-04-01

    The aim of the study was to evaluate whether two dietary approaches recommended for diabetes mellitus and cardiovascular prevention-high-MUFA or complex carbohydrates/fiber-differently influence inflammation. A 4-week crossover study in 12 individuals with type 2 diabetes was performed. Fasting and postprandial hs-CRP plasma levels were not significantly different after a high-carbohydrate/high-fiber/low-glycemic index (CHO/fiber) and a high-MUFA diet. Compared with fasting, hs-CRP levels decreased significantly after the MUFA but not after the CHO/fiber meal. Triglyceride-rich lipoproteins were significantly lower after the CHO/fiber than the MUFA diet. At fasting and postprandially, hs-CRP correlated with triglyceride in whole plasma, chylomicrons, small and large VLDL after the CHO/fiber but not after the MUFA diet. In conclusion, a MUFA-rich diet and a carbohydrate/fiber-rich diet induced similar effects on plasma hs-CRP concentrations. However, these dietary approaches seem to influence hs-CRP levels through different mechanisms. i.e., direct acute postprandial effects by MUFA and triglyceride-rich lipoproteins mediated effects by CHO/fiber.

  20. Elevated fasting plasma ghrelin in prader-willi syndrome adults is not solely explained by their reduced visceral adiposity and insulin resistance.

    PubMed

    Goldstone, Anthony P; Thomas, E Louise; Brynes, Audrey E; Castroman, Gabriela; Edwards, Ray; Ghatei, Mohammad A; Frost, Gary; Holland, Anthony J; Grossman, Ashley B; Korbonits, Márta; Bloom, Stephen R; Bell, Jimmy D

    2004-04-01

    Plasma ghrelin is elevated in Prader-Willi syndrome (PWS). This might contribute to obesity or GH deficiency in such patients. Visceral adiposity and insulin resistance are reduced in PWS, which might lead to hyperghrelinemia. We measured fasting plasma ghrelin in control female (n = 39), PWS female (n = 12), and PWS male (n = 6) adults. In controls and PWS, ghrelin was negatively correlated with visceral adiposity, fasting insulin, and homeostasis model insulin resistance index. There was no significant correlation with serum IGF-I in PWS. In stepwise linear regression, visceral adiposity (P < 0.02) had a stronger inverse correlation with ghrelin than sc fat depots in controls and PWS, possibly through hyperinsulinemia, as the correlations with insulin resistance were even stronger (P < 0.01). PWS females had significantly (P < 0.001) elevated ghrelin (mean +/- SD, 661 +/- 360 pg/ml), compared with both nonobese (363 +/- 163) and obese (191 +/- 66) controls. Ghrelin was increased 3.4- to 3.6-fold in PWS females adjusting for total adiposity, 3.2- to 3.4-fold adjusting for visceral adiposity, and 3.0-fold adjusting for insulin resistance. Fasting plasma glucagon-like peptide-1 was normal in PWS females. The hyperghrelinemia in PWS adults is therefore not solely explained by their reduced visceral adiposity and relative hypoinsulinemia. Its cause and consequences await further elucidation.

  1. Improvement of fasting plasma glucose level after ingesting moderate amount of dietary fiber in Japanese men with mild hyperglycemia and visceral fat obesity.

    PubMed

    Kobayakawa, Akira; Suzuki, Tomoo; Ikami, Takao; Saito, Morio; Yabe, Daisuke; Seino, Yutaka

    2013-06-01

    A double-blind, randomized, controlled study was conducted to evaluate the effects of a moderate amount of dietary fiber intake on fasting plasma glucose level and physical characteristics in Japanese men with mild hyperglycemia and visceral fat obesity. Thirty men with mild hyperglycemia (>5.6 mmol/L) and visceral fat accumulation (>100 cm²) ingested 7.5 g/day of dietary fiber for 12 weeks. An abdominal computed tomography scan was performed at baseline and at week 12. Blood was drawn every 4 weeks. In the test food group, fasting plasma glucose level was reduced with time, and the difference between the test food group and placebo group was statistically significant at week 12. Body weight and body mass index were also reduced with time, but visceral and subcutaneous fat areas did not change significantly during the study period. The results suggest that even a moderate amount of dietary fiber intake may be beneficial for managing the fasting plasma glucose level concomitant with insulin resistance, body weight, and body mass index in Japanese men with mild hyperglycemia and visceral fat obesity.

  2. Escaping the Hemoglobin A1c-Centric World in Evaluating Diabetes Mellitus Interventions

    PubMed Central

    Vigersky, Robert A.

    2015-01-01

    Any intervention in patients with diabetes must consider its effect on both the incidence of hypoglycemia and hemoglobin A1c. Yet, there is no single metric that expresses these key factors simultaneously. Such a composite metric would permit clinicians, regulators, manufacturers, payers, and researchers to more easily evaluate the merits of an intervention as well as enable the comparison of qualitatively different interventions. This article proposes a composite metric, the hypoglycemia-A1c score (HAS), as the basis for a more comprehensive approach for the stakeholders in diabetes treatment to better understand how an intervention affects diabetes management. The article also demonstrates how additional parameters such as effects on weight, quality of life, and costs could be included in such a scoring system. PMID:25697718

  3. Hemoglobin A1c Testing and Amputation Rates in Black, Hispanic, and White Medicare Patients

    PubMed Central

    Suckow, Bjoern D.; Newhall, Karina A.; Bekelis, Kimon; Faerber, Adrienne E.; Gottlieb, Daniel J.; Skinner, Jonathan S.; Stone, David H.; Goodney, Philip P.

    2016-01-01

    Background Major (above-knee or below-knee) amputation is a complication of diabetes and is seen more common among black and Hispanic patients. While amputation rates have declined for patients with diabetes in the last decade, it remains unknown if these improvements have equitably extended across racial groups and if measures of diabetic care, such as hemoglobin A1c testing, are associated with these improvements. We set out to characterize secular changes in amputation rates among black, Hispanic, and white patients, and to determine associations between hemoglobin A1c testing and amputation risk. Methods We identified 11,942,840 Medicare patients (55% female) with diabetes over the age of 65 years between 2002 and 2012 and followed them for a mean of 6.6 years. Of these, 86% were white, 11.5% were black, and 2.5% were Hispanic. We recorded the occurrence of major amputation and hemoglobin A1c testing during this time period and studied secular changes in amputation rate by race (black, Hispanic, and white). Finally, we examined associations between amputation risk and hemoglobin A1c testing. We measured both the presence of any testing and testing consistency using 3 categories: poor consistency (hemoglobin A1c testing in 0–50% of years), medium consistency (testing in 50–90% of years), and high consistency (testing in >90% of the years in the cohort). Results Between 2002 and 2012, the average major lower-extremity amputation rate in diabetic Medicare patients was 1.78 per 1,000 per year for black patients, 1.15 per 1,000 per year for Hispanic patients, and 0.56 per 1,000 per year for white patients (P < 0.001). Over the study period, the incidence of major amputation in Medicare patients with diabetes declined by 54%, from 1.15 per 1,000 in 2002 to 0.53 per 1,000 in 2012 (rate ratio = 0.53, 95% CI = 0.51–0.54). The reduction in amputation rate was similar across racial groups: 52% for black patients, 61% for Hispanic patients, and 55% for white patients

  4. High performance diagnostics for Time-Of-Flight and X ray measurements in laser produced plasmas, based on fast diamond detectors

    NASA Astrophysics Data System (ADS)

    De Angelis, R.; Consoli, F.; Verona, C.; Di Giorgio, G.; Andreoli, P.; Cristofari, G.; Cipriani, M.; Ingenito, F.; Marinelli, M.; Verona-Rinati, G.

    2016-12-01

    The paper reports about the use of single-crystal Chemical Vapour Deposited (CVD) diamonds as radiation detectors in laser-matter interaction experiments on the ABC laser in ENEA - Frascati. The detectors have been designed and realized by University of Tor Vergata - Rome. The interdigital configuration and the new design of the bias-tee voltage supply units guarantee a fast time response. The detectors are sensitive to soft-X photons and to particles. A remarkable immunity to electromagnetic noise, associated with the laser-target interaction, makes them especially useful for the measurements of the time of flight of fast particles. A novel diamond assembly has been tested in plasmas generated by the ABC laser in the nanosecond regime at intensities I=1013÷ 14 W/cm2, where contributions from X rays, fast electrons and ions could be observed.

  5. Modeling of fast neutral-beam-generated ion effects on MHD-spectroscopic observations of resistive wall mode stability in DIII-D plasmas [Modeling of fast neutral-beam-generated ion effects on MHD spectroscopic observations of RWM stability in DIII-D plasmas

    DOE PAGES

    Turco, Francesca; Turnbull, Alan D.; Hanson, Jeremy M.; ...

    2015-02-03

    Experiments conducted at DIII-D investigate the role of drift kinetic damping and fast neutral beam injection (NBI)-ions in the approach to the no-wall βN limit. Modelling results show that the drift kinetic effects are significant and necessary to reproduce the measured plasma response at the ideal no-wall limit. Fast neutral-beam ions and rotation play important roles and are crucial to quantitatively match the experiment. In this paper, we report on the model validation of a series of plasmas with increasing βN, where the plasma stability is probed by active magnetohydrodynamic (MHD) spectroscopy. The response of the plasma to an externallymore » applied field is used to probe the stable side of the resistive wall mode and obtain an indication of the proximity of the equilibrium to an instability limit. We describe the comparison between the measured plasma response and that calculated by means of the drift kinetic MARS-K code, which includes the toroidal rotation, the electron and ion drift-kinetic resonances, and the presence of fast particles for the modelled plasmas. The inclusion of kinetic effects allows the code to reproduce the experimental results within ~13% for both the amplitude and phase of the plasma response, which is a significant improvement with respect to the undamped MHD-only model. The presence of fast NBI-generated ions is necessary to obtain the low response at the highest βN levels (~90% of the ideal no-wall limit). Finally, the toroidal rotation has an impact on the results, and a sensitivity study shows that a large variation in the predicted response is caused by the details of the rotation profiles at high βN.« less

  6. Modeling of fast neutral-beam-generated ion effects on MHD-spectroscopic observations of resistive wall mode stability in DIII-D plasmas [Modeling of fast neutral-beam-generated ion effects on MHD spectroscopic observations of RWM stability in DIII-D plasmas

    SciTech Connect

    Turco, Francesca; Turnbull, Alan D.; Hanson, Jeremy M.; Navratil, Gerald A.

    2015-02-03

    Experiments conducted at DIII-D investigate the role of drift kinetic damping and fast neutral beam injection (NBI)-ions in the approach to the no-wall βN limit. Modelling results show that the drift kinetic effects are significant and necessary to reproduce the measured plasma response at the ideal no-wall limit. Fast neutral-beam ions and rotation play important roles and are crucial to quantitatively match the experiment. In this paper, we report on the model validation of a series of plasmas with increasing βN, where the plasma stability is probed by active magnetohydrodynamic (MHD) spectroscopy. The response of the plasma to an externally applied field is used to probe the stable side of the resistive wall mode and obtain an indication of the proximity of the equilibrium to an instability limit. We describe the comparison between the measured plasma response and that calculated by means of the drift kinetic MARS-K code, which includes the toroidal rotation, the electron and ion drift-kinetic resonances, and the presence of fast particles for the modelled plasmas. The inclusion of kinetic effects allows the code to reproduce the experimental results within ~13% for both the amplitude and phase of the plasma response, which is a significant improvement with respect to the undamped MHD-only model. The presence of fast NBI-generated ions is necessary to obtain the low response at the highest βN levels (~90% of the ideal no-wall limit). Finally, the toroidal rotation has an impact on the results, and a sensitivity study shows that a large variation in the predicted response is caused by the details of the rotation profiles at high βN.

  7. The Importance of HbA1c Control in Patients with Subclinical Hypothyroidism

    PubMed Central

    Billic-Komarica, Edina; Beciragic, Amela; Junuzovic, Dzelaludin

    2012-01-01

    Goal: To investigate the correlation between TSH and HbA1c in the treatment of L-thyroxine in the process of glycemic control in patients with subclinical hypothyroidism. Patients and methods: The sample consisted of 100 patients, mean age 51.75±3.23 years, BMI=27.97±4.52 kg/m2, with SH (TSH>4.2 mU/L and normal serum T3 and T4). Laboratory diagnosis included the determination of free T3, free T4, thyroid antibodies, Tg, insulin, C-peptide and glucose during the OGTT, HbA1c, CRP and lipid levels. 20 patients with SH had prediabetes and 38 patients had DM. All patients were treated with low doses of L-thyroxine (25-50ug) and all were physically active. Results: After 6 months of treatment with L-thyroxine, the patients had normal or decreased TSH (5.85±0.92 vs. 3.54±0.55 mU/L), insulin levels (114.64±24.11 vs. 96.44±17.26 pmol/L) significantly reduced HbA1c (6.74±1.01 vs. 6.26±1.12) is reduced. Conclusion: The correlation between TSH and HbA1c was positive and significant (r=0.46). This indicates a significant effect of treatment with L-thyroxine on glycemic control in patients with subclinical hypothyroidism. PMID:23678326

  8. A review of variant hemoglobins interfering with hemoglobin A1c measurement.

    PubMed

    Little, Randie R; Roberts, William L

    2009-05-01

    Hemoglobin A1c (HbA1c) is used routinely to monitor long-term glycemic control in people with diabetes mellitus, as HbA1c is related directly to risks for diabetic complications. The accuracy of HbA1c methods can be affected adversely by the presence of hemoglobin (Hb) variants or elevated levels of fetal hemoglobin (HbF). The effect of each variant or elevated HbF must be examined with each specific method. The most common Hb variants worldwide are HbS, HbE, HbC, and HbD. All of these Hb variants have single amino acid substitutions in the Hb beta chain. HbF is the major hemoglobin during intrauterine life; by the end of the first year, HbF falls to values close to adult levels of approximately 1%. However, elevated HbF levels can occur in certain pathologic conditions or with hereditary persistence of fetal hemoglobin. In a series of publications over the past several years, the effects of these four most common Hb variants and elevated HbF have been described. There are clinically significant interferences with some methods for each of these variants. A summary is given showing which methods are affected by the presence of the heterozygous variants S, E, C, and D and elevated HbF. Methods are divided by type (immunoassay, ion-exchange high-performance liquid chromatography, boronate affinity, other) with an indication of whether the result is artificially increased or decreased by the presence of a Hb variant. Laboratorians should be aware of the limitations of their method with respect to these interferences.

  9. A non-linear 4-wave resonant model for non-perturbative fast ion interactions with Alfv'enic modes in burning plasmas

    NASA Astrophysics Data System (ADS)

    Zonca, Fulvio; Chen, Liu

    2007-11-01

    We adopt the 4-wave modulation interaction model, introduced by Chen et al [1] for analyzing modulational instabilities of the radial envelope of Ion Temperature Gradient driven modes in toroidal geometry, extending it to the modulations on the fast particle distribution function due to nonlinear Alfv'enic mode dynamics, as proposed in Ref. [2]. In the case where the wave-particle interactions are non-perturbative and strongly influence the mode evolution, as in the case of Energetic Particle Modes (EPM) [3], radial distortions (redistributions) of the fast ion source dominate the mode nonlinear dynamics. In this work, we show that the resonant particle motion is secular with a time-scale inversely proportional to the mode amplitude [4] and that the time evolution of the EPM radial envelope can be cast into the form of a nonlinear Schr"odinger equation a la Ginzburg-Landau [5]. [1] L. Chen et al, Phys. Plasmas 7 3129 (2000) [2] F. Zonca et al, Theory of Fusion Plasmas (Bologna: SIF) 17 (2000) [3] L. Chen, Phys. Plasmas 1, 1519 (1994).[4] F. Zonca et al, Nucl. Fusion 45 477 (2005) [5] F. Zonca et al, Plasma Phys. Contr. Fusion 48 B15 (2006)

  10. Inpatient HbA1c testing: a prospective observational study

    PubMed Central

    Nanayakkara, Natalie; Nguyen, Hang; Churilov, Leonid; Kong, Alvin; Pang, Nyuk; Hart, Graeme K; Owen-Jones, Elizabeth; White, Jennifer; Ross, Jane; Stevenson, Victoria; Bellomo, Rinaldo; Lam, Que; Crinis, Nicholas; Robbins, Raymond; Johnson, Doug; Baker, Scott T; Zajac, Jeffrey D; Ekinci, Elif I

    2015-01-01

    Objective To use admission inpatient glycated hemoglobin (HbA1c) testing to help investigate the prevalence of unrecognized diabetes, the cumulative prevalence of unrecognized and known diabetes, and the prevalence of poor glycemic control in both. Moreover, we aimed to determine the 6-month outcomes for these patients. Finally, we aimed to assess the independent association of diabetes with these outcomes. Research, design, and methods Prospective observational cohort study conducted in a tertiary hospital in Melbourne, Australia. Patients A cohort of 5082 inpatients ≥54 years admitted between July 2013 and January 2014 underwent HbA1c measurement. A previous diagnosis of diabetes was obtained from the hospital medical record. Patient follow-up was extended to 6 months. Results The prevalence of diabetes (known and unrecognized) was 34%. In particular, we identified that unrecognized but HbA1c-confirmed diabetes in 271 (5%, 95% CI 4.7% to 6.0%) patients, previously known diabetes in 1452 (29%, 95% CI 27.3% to 29.8%) patients; no diabetes in 3359 (66%, 95% CI 64.8–67.4%) patients. Overall 17% (95% CI 15.3% to 18.9%) of patients with an HbA1c of >6.5% had an HbA1c ≥8.5%. After adjusting for age, gender, Charlson Index score, estimated glomerular filtration rate, and hemoglobin levels, with admission unit treated as a random effect, patients with previously known diabetes had lower 6-month mortality (OR 0.69, 95% CI 0.56 to 0.87, p=0.001). However, there were no significant differences in proportions of intensive care unit admission, mechanical ventilation or readmission within 6 months between the 3 groups. Conclusions Approximately one-third of all inpatients ≥54 years of age admitted to hospital have diabetes of which about 1 in 6 was previously unrecognized. Moreover, poor glycemic control was common. Proportions of intensive care unit admission, mechanical ventilation, or readmission were similar between the groups. Finally, diabetes was

  11. Electrochemical detection of HbA1c, a marker [correction of maker] for diabetes, using a flow immunoassay system.

    PubMed

    Tanaka, Tsuyoshi; Tsukube, Shoko; Izawa, Kojiro; Okochi, Mina; Lim, Tae-Kyu; Watanabe, Shugo; Harada, Manabu; Matsunaga, Tadashi

    2007-04-15

    An on-chip electrochemical flow immunoassay system for the detection of hemoglobin A1c (HbA1c) was developed using anti-human hemoglobin (Hb) IgG labeled with ferrocene monocarboxylic acid (Fc-COOH) and boronate-affinity chromatography. An on-chip column packed with boronate-activated agarose beads was used for the separation of HbA1c from both non-glycated Hb and free antibody. Anti-human Hb IgG conjugated to Fc-COOH (Fc-IgG) was used for the electrochemical detection of HbA1c. The assay procedure included immunoreactions with Fc-IgG and HbA1c, separation of immunocomplexes by boronate affinity, and electrochemical detection of Fc-IgG-HbA1c immunocomplexes. The immunoreaction mixtures were injected onto a boronate-affinity column. HbA1c-antibody complexes were then trapped onto the column by the affinity of HbA1c to boronic acid. Subsequently, elution buffer containing sorbitol was applied to elute HbA1c-antibody complexes and a current was detected by applying 600 mV versus Ag/AgCl. The elution signal was an estimation of the HbA1c amount. A linear correlation between the increase of current and HbA1c concentration was obtained up to an HbA1c concentration of 500 microg/ml. The HbA1c flow immunoassay was successfully achieved using hemolysates. This electrochemical flow immunoassay system enabled us to construct a novel point-of-care testing device for the monitoring of glycated proteins including HbA1c.

  12. Association between the rs4753426 polymorphism in MTNR1B with fasting plasma glucose level and pancreatic β-cell function in gestational diabetes mellitus.

    PubMed

    Zhan, Y; Li, C; Gao, Q; Chen, J; Yu, S; Liu, S G

    2015-08-03

    We investigated the association between rs4753426 single nucleotide polymorphisms in the melatonin receptor 1B (MTNR1B) gene and the risk of developing gestational diabetes mellitus (GDM). A total of 516 gravidas (186 with GDM and 330 non-diabetic controls) were enrolled in the study. Genotype and allele frequencies of rs4753426 in the MTNR1B gene were detected by DNA sequencing. Fasting plasma glucose and fasting insulin levels were measured to calculate the homeostasis model assessment for insulin resistance (HOMA-IR) and for β-cell function. Three genotypes (CC, CT, and TT) were found in both groups. The frequencies of CC, CT, and TT genotypes for the GDM group were 70.97, 22.58, and 6.45% vs 53.03, 39.70, and 7.27% in the control group, respectively. Significant differences were observed in genotype frequencies between groups (P < 0.05). T and C allele frequencies in the GDM group were 17.74 and 82.26%, respectively, and in the control group were 27.12 and 72.88%, respectively. Significant differences in T and C allele frequencies were found between groups (P < 0.05). In the GDM group, the C allele was associated with increased fasting plasma glucose level and reduced pancreatic β-cell function (P < 0.05). There were no significant differences in total cholesterol, triglyceride, low-density lipoprotein, high-density lipoprotein concentration, or HOMA-IR between groups (P > 0.05). The single nucleotide polymorphism rs4753426 in MTNR1B may be a susceptibility gene locus for GDM, and the C allele may contribute to the increased fasting plasma glucose level and reduced pancreatic β-cell function.

  13. Early prediction of new-onset diabetes mellitus by fifth-day fasting plasma glucose, pulse pressure, and proteinuria.

    PubMed

    Rodrigo, E; Santos, L; Piñera, C; Quintanar, J A; Ruiz, J C; Fernández-Fresnedo, G; Palomar, R; Gómez-Alamillo, C; Arias, M

    2011-01-01

    Renal transplant recipients are at high risk of cardiovascular disease (CVD). New-onset diabetes mellitus after transplantation (NODAT) contributes to the risk of CVD, reducing graft and patient survival. To improve outcome of kidney transplant recipients, it is of great interest to identify those patients who will develop NODAT. The aim of our study was to explore the predictive value of fifth-day fasting plasma glucose (FPG), third-month proteinuria, and pulse pressure (PP) for NODAT development. We analyzed 282 non-previously-diabetic kidney transplants in our center. Fifth-day FPG, PP, and third-month 24-hour proteinuria were collected. NODAT was defined at month 12 according to the "consensus guidelines": symptoms of diabetes plus casual glucose concentrations ≥ 200 mg/dL or FPG ≥ 126 mg/dL. Some 46 patients (16.3%) developed NODAT at month 12. Fifth-day FPG (133 ± 35 vs 108 ± 16 mg/dL, P < .001) and PP (57 ± 17 vs 49 ± 15 mm Hg, P = .007) were significantly higher in patients at risk for NODAT, but there was no difference in third-month proteinuria (652 ± 959 vs 472 ± 1336 mg, P = .390). A multivariate regression model showed an increased risk for NODAT associated with recipient age, body mass index, smoking habit, and a fifth-day FPG ≥ 126 mg/dL (relative risk 4.784, 95% confidence interval 2.121-10.788, P = .0002). The negative predictive value of a fifth-day FPG ≥ 126 mg/dL for predicting 1-year NODAT was 89.4%. Fifth-day FPG was independently related to NODAT development. The detection of a fifth-day FPG ≥ 126 mg/dL increases the risk of suffering NODAT more than 4 times. Fifth-day FPG < 126 mg/dL allows us to identify a transplant population with a low risk (near 10%) for NODAT.

  14. An influence of long-lasting and gradual magnetic flux transport on fate of magnetotail fast plasma flows: An energetic particle injection substorm event study

    NASA Astrophysics Data System (ADS)

    Nowada, Motoharu; Fu, Suiyan; Parks, George K.; Pulkkinen, Tuija I.; Pu, Zuyin

    2014-10-01

    Based on multi-satellite and ground observations, we investigated an influence of long-lasting and gradual enhancements of magnetic flux transport rate on the magnetotail fast flow duration. On March 10th, 2009, THEMIS-B, which was located in the central plasma sheet of middle distant magnetotail (XGSM ~-25.8 RE), observed the fast flows with the velocity exceeding 300 km/s, lasting over 3 h for intense southward Interplanetary Magnetic Field (IMF) period. During long-lasting fast flows, AL index variations were very extensive and their recovery was much slow. Pi 2 waves were observed at the ground observatories around the THEMIS's footpoints and at low-/mid-latitudes. The aspect for these AL variations suggests Steady Magnetospheric Convection (SMC), but clear substorm signatures were also observed. Further magnetic dipolarization was detected by THEMIS-A at XGSM ~-8.2 RE and its nearby THEMIS-E. Only THEMIS-A observed the associated energetic electron flux enhancements. Therefore, the fast flows occurred during substorm with energetic particle injections at “imitative” SMC, which would be driven by prolonged intense southward IMF. The cumulative transport rates of magnetic and Poynting fluxes consecutively and gradually enhanced. On the other hand, THEMIS-C detected much shorter fast flows with the duration of 37 min at XGSM ~-18.1 RE and weak/gradual substorm-associated dipolarization. However, the cumulative magnetic flux transport rate was enhanced only during the fast flow interval and was saturated after the fast flows. From different magnetic transport rate profiles at THEMIS-B and THEMIS-C, the realms of dipolar-configured field lines expanded to near THEMIS-C's position responsible for long-lasting fast flow-associated consecutive and gradual magnetic flux pileup. Because the resultant “high-speed flow braking” region was retreated into a few RE tailward direction, long-lasting fast flows were almost stemmed. These results suggest that the

  15. Effect of intake on fasting heat production, respiratory quotient and plasma metabolites measured using the washed rumen technique

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective was to investigate the effect of intake prior to fasting on concentrations of metabolites and hormones, respiratory quotient (RQ) and fasting heat production (HP) using the washed rumen technique and to compare these values with those from the fed state. Six Holstein steers (360 ± 22 k...

  16. Differential effects of GH stimulation on fasting and prandial metabolism and plasma IGFs and IGF-binding proteins in lean and obese sheep.

    PubMed

    McCann, J P; Loo, S C; Aalseth, D L; Abribat, T

    1997-08-01

    The effect of body condition per se on plasma IGFs and IGF-binding proteins (IGFBPs) and the whole-body metabolic responses to recombinant DNA-derived bovine GH (rbGH) in both the fed and the fasted state were determined in lean and dietary obese sheep (n = 6/group). Sheep at zero-energy balance and equilibrium body weight were injected s.c. for 12 days with 100 micrograms/kg rbGH immediately before their morning feeding. Before GH treatment, fasting plasma concentrations of insulin (17.0 +/- 1.9 vs 7.5 +/- 0.7 microU/ml), IGF-I (345 +/- 25 vs 248 +/- 10 ng/ml), glucose (52.6 +/- 1.1 vs 48.3 +/- 0.7 mg/dl), and free fatty acid (FFA) (355 +/- 45 vs 229 +/- 24 nmol/ml) were greater (P < 0.05) and those of GH (1.1 +/- 0.2 vs 2.6 +/- 0.3 ng/ml) were lower (P < 0.05) in obese than in lean sheep. Fasting concentrations of IGF-II and glucagon were not affected (P > 0.05) by obesity. GH concentrations were increased equivalently by 6-9 ng/ml in lean and obese sheep during GH treatment. GH caused an immediate and a marked fivefold increase in the fasting insulin level in obese sheep but only minimally affected insulin concentration in lean sheep. The increment in fasting glucose during GH treatment was greater (P < 0.05) in obese (8-12 mg/dl) than in lean (2-5 mg/dl) sheep. Frequent measurements in the first 8 h after feeding and injection of excipient (day 0) or the first (day 1) sixth (day 6) and twelfth (day 12) daily injection of GH showed that prandial metabolism in both groups of sheep was affected minimally by GH. However, GH treatment on day 1 (not days 6 or 12) acutely attenuated the feeding-induced suppression of plasma FFA in both groups of sheep and this effect was significantly greater in obese than in lean sheep. Although obese sheep were hyposomatotropic, the basal and GH-induced increases in plasma IGF-I concentrations were greater (P < 0.05) in obese than in lean sheep. Plasma IGF-II was unaffected by obesity and was not increased by GH stimulation. Western

  17. Validation of fast-ion D-alpha spectrum measurements during EAST neutral-beam heated plasmas

    NASA Astrophysics Data System (ADS)

    Huang, J.; Heidbrink, W. W.; von Hellermann, M. G.; Stagner, L.; Wu, C. R.; Hou, Y. M.; Chang, J. F.; Ding, S. Y.; Chen, Y. J.; Zhu, Y. B.; Jin, Z.; Xu, Z.; Gao, W.; Wang, J. F.; Lyu, B.; Zang, Q.; Zhong, G. Q.; Hu, L.; Wan, B.

    2016-11-01

    To investigate the fast ion behavior, a fast ion D-alpha (FIDA) diagnostic system has been installed on EAST. Fast ion features can be inferred from the Doppler shifted spectrum of Balmer-alpha light from energetic hydrogenic atoms. This paper will focus on the validation of FIDA measurements performed using MHD-quiescent discharges in 2015 campaign. Two codes have been applied to calculate the Dα spectrum: one is a Monte Carlo code, Fortran 90 version FIDASIM, and the other is an analytical code, Simulation of Spectra (SOS). The predicted SOS fast-ion spectrum agrees well with the measurement; however, the level of fast-ion part from FIDASIM is lower. The discrepancy is possibly due to the difference between FIDASIM and SOS velocity distribution function. The details will be presented in the paper to primarily address comparisons of predicted and observed spectrum shapes/amplitudes.

  18. A1cNow® InView™: A New Simple Method for Office-Based Glycohemoglobin Measurement

    PubMed Central

    Mattewal, Amarbir; Aldasouqi, Saleh; Solomon, David; Gossain, Ved; Koller, Anthony

    2007-01-01

    Background Glycohemoglobin A1c (HbA1c) is a universally accepted tool for glycemic control. Portable HbA1c devices for use in physicians' offices are desirable because they provide immediate results that physicians can share with their patients. This has been shown to enhance self-management in patients with diabetes. We undertook this study to evaluate the accuracy and precision of a recently introduced device, the A1cNow® InView™ capillary monitor. Methods Previously tested EDTA-preserved whole blood samples from our laboratory pool were preselected based on the results of HbA1c to cover a range from 4 to 13%. HbA1c was then measured using an A1cNow InView capillary monitor. Blinded aliquots of these samples were then sent to a National Glycohemoglobin Standardization Program (NGSP)-certified reference laboratory for comparison. One sample with a laboratory HbA1c result of 9.2% was measured with the InView device nine successive times to assess the device precision. The consistency between the measurement of HbA1c measured by the reference laboratory and the A1cNow InView device was analyzed via linear regression. Results Thirty-five samples were tested. The correlation between HbA1c measured by the InView device and the reference laboratory, as well as our own laboratory, was 0.96. The coefficient of variation was 2.71%. Conclusions Results of this study confirm the accuracy and precision of the InView capillary HbA1c monitor. However, the feasibility, reproducibility, and cost-effectiveness of this promising device in the real-life settings of physicians' offices must be verified by prospective clinical studies. PMID:19885160

  19. Hybrid simulation of fast ion dynamics in the presence of off-axis fishbone-like modes in high-beta JT-60U plasmas

    NASA Astrophysics Data System (ADS)

    Bierwage, Andreas; Aiba, Nobuyuki; Matsunaga, Go; Shinohara, Koji; Todo, Yasushi; Yagi, Masatoshi

    2013-10-01

    The MHD-PIC hybrid code MEGA is used to simulate high-beta JT-60U plasmas in regimes near marginal MHD ballooning stability and driven by neutral beams. The goal of this research is to study the transport of fast ions caused by experimentally observed fishbone-like modes that peak off-axis (near the q = 2 surface) and have frequencies well below the accumulation points of the beta-induced gap of the shear Alfvén continuum. The approach chosen is as follows. Before examining the physics via parameter scans and case studies, the relevance of the simulation model is verified by checking whether the code can reproduce a plasma response with properties similar to those seen in the experiments. For this purpose, the simulation scenario is set up as realistically as currently possible: with realistic plasma shape and bulk pressure, and a fast ion distribution that is consistent with particle sources and collisions. The methods used and first results are reported and discussed. This work is partly supported by Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (JSPS).

  20. Gender, but not CYP7A1 or SLCO1B1 polymorphism, affects the fasting plasma concentrations of bile acids in human beings.

    PubMed

    Xiang, Xiaoqiang; Backman, Janne T; Neuvonen, Pertti J; Niemi, Mikko

    2012-03-01

    Cholesterol 7α-hydroxylase (CYP7A1) is the rate-limiting enzyme of bile acid production in human beings, and organic anion-transporting polypeptide 1B1 (OATP1B1) may influence bile acid hepatic uptake and cholesterol and bile acid synthesis rate. Our purpose was to investigate the effects of gender and CYP7A1 and SLCO1B1 polymorphisms on the fasting plasma concentrations of bile acids, bile acid synthesis marker and total cholesterol in a Finnish population. Fasting plasma concentrations of 16 endogenous bile acids, their synthesis marker (7α-hydroxy-4-cholesten-3-one) and total cholesterol were measured in 243 samples from 143 healthy volunteers. The volunteers were genotyped for 6 haplotype-tagging single-nucleotide polymorphisms (SNPs) of CYP7A1 and two functionally relevant SNPs in SLCO1B1. The mean plasma concentrations of chenodeoxycholic acid, glycochenodeoxycholic acid, ursodeoxycholic acid and glycoursodeoxycholic acid were 61-111% higher in men than in women (P ≤ 0.001). Accordingly, the mean concentration of total bile acids was 51% higher in men than in women (P = 0.001). The CYP7A1 rs8192879 and rs1023652 SNPs were associated with deoxycholic acid and hyodeoxycholic acid concentrations, respectively, but the associations were not significant after correction for multiple testing. None of the six CYP7A1 SNPs was associated with the plasma concentrations of cholesterol or 7α-hydroxy-4-cholesten-3-one. SLCO1B1 genotype was associated with total plasma cholesterol concentration only, but the association was not significant after correction for multiple testing. In general, the gender contributes substantially more to variation in fasting plasma bile acid concentrations than CYP7A1 or SLCO1B1 polymorphism do. Common genetic variability in CYP7A1 is unlikely to play a significant role in cholesterol metabolism and bile acid homeostasis under normal physiological conditions.

  1. High-energy-density plasmas generation on GEKKO-LFEX laser facility for fast-ignition laser fusion studies and laboratory astrophysics

    NASA Astrophysics Data System (ADS)

    Fujioka, S.; Zhang, Z.; Yamamoto, N.; Ohira, S.; Fujii, Y.; Ishihara, K.; Johzaki, T.; Sunahara, A.; Arikawa, Y.; Shigemori, K.; Hironaka, Y.; Sakawa, Y.; Nakata, Y.; Kawanaka, J.; Nagatomo, H.; Shiraga, H.; Miyanaga, N.; Norimatsu, T.; Nishimura, H.; Azechi, H.

    2012-12-01

    The world's largest peta watt (PW) laser LFEX, which delivers energy up to 2 kJ in a 1.5 ps pulse, has been constructed beside the GEKKO XII laser at the Institute of Laser Engineering, Osaka University. The GEKKO-LFEX laser facility enables the creation of materials having high-energy-density which do not exist naturally on the Earth and have an energy density comparable to that of stars. High-energy-density plasma is a source of safe, secure, environmentally sustainable fusion energy. Direct-drive fast-ignition laser fusion has been intensively studied at this facility under the auspices of the Fast Ignition Realization Experiment (FIREX) project. In this paper, we describe improvement of the LFEX laser and investigations of advanced target design to increase the energy coupling efficiency of the fast-ignition scheme. The pedestal of the LFEX pulse, which produces a long preformed plasma and results in the generation of electrons too energetic to heat the fuel core, was reduced by introducing an amplified optical parametric fluorescence quencher and saturable absorbers in the front-end system of the LFEX laser. Since fast electrons are scattered and stopped by the strong electric field of highly ionized high-Z (i.e. gold) ions, a low-Z cone was studied for reducing the energy loss of fast electrons in the cone tip region. A diamond-like carbon cone was fabricated for the fast-ignition experiment. An external magnetic field, which is demonstrated to be generated by a laser-driven capacitor-coil target, will be applied to the compression of the fuel capsule to form a strong magnetic field to guide the fast electrons to the fuel core. In addition, the facility offers a powerful means to test and validate astronomical models and computations in the laboratory. As well as demonstrating the ability to recreate extreme astronomical conditions by the facilities, our theoretical description of the laboratory experiment was compared with the generally accepted explanation

  2. Update on diabetes diagnosis: a historical review of the dilemma of the diagnostic utility of glycohemoglobin A1c and a proposal for a combined glucose-A1c diagnostic method.

    PubMed

    Aldasouqi, Saleh A; Gossain, Ved V

    2012-01-01

    The role of glycohemoglobin A1c (A1c) for the diagnosis of diabetes has been debated for over three decades. Recently, the American Diabetes Association (ADA) has recommended adding A1c as an additional criterion for diabetes diagnosis. In view of the continued debate about the diagnostic utility of A1c, and in view of the unabated burden of undiagnosed diabetes, the search for alternative diagnostic methods is discussed. A historical literature review is provided, in view of the new ADA diagnostic guidelines, and a proposal is provided for combining A1c and a glucose measurement as a diagnostic alternative/adjunct to the use of a single criterion. This proposal is based on the non-overlapping of the advantages and disadvantages of these individual tests. The cost-effectiveness of this method remains to be tested.

  3. The Effect of Non-surgical Periodontal Therapy on Hemoglobin A1c Levels in Persons with Type 2 Diabetes and Chronic Periodontitis: A Randomized Clinical Trial

    PubMed Central

    Engebretson, Steven P.; Hyman, Leslie G.; Michalowicz, Bryan S.; Schoenfeld, Elinor R.; Gelato, Marie C.; Hou, Wei; Seaquist, Elizabeth R.; Reddy, Michael S.; Lewis, Cora E.; Oates, Thomas W.; Tripathy, Devjit; Katancik, James A.; Orlander, Philip R.; Paquette, David W.; Hanson, Naomi Q.; Tsai, Michael Y.

    2014-01-01

    Importance Chronic periodontitis, a destructive inflammatory disorder of the supporting structures of the teeth, is prevalent in patients with diabetes. Limited evidence suggests that periodontal therapy may improve glycemic control. Objective To determine if non-surgical periodontal treatment reduces hemoglobin A1c (HbA1c) in persons with type 2 diabetes (DM) and moderate to advanced chronic periodontitis. Design, Setting and Participants The Diabetes and Periodontal Therapy Trial (DPTT) is a 6-month, single-masked, randomized, multi-center clinical trial. Participants had DM, were taking stable doses of medications, had HbA1c ≥7% and <9%, and untreated periodontitis. Five hundred fourteen participants were enrolled between November 2009 and March 2012 from diabetes and dental clinics and communities affiliated with five academic medical centers. Intervention The treatment group (n=257) received scaling and root planing plus chlorhexidine oral rinse at baseline, and supportive periodontal therapy at three and six months. The control group (n=257) received no treatment for six months. Main Outcome Measure Difference in HbA1c change from baseline between groups at six months. Secondary outcomes included changes in probing pocket depths, clinical attachment loss, bleeding on probing, gingival index, fasting glucose, and the Homeostasis Model Assessment (HOMA2). Results Enrollment was stopped early due to futility. At 6 months, the periodontal therapy group increased HbA1c 0.17% (1.0) (mean (SD)) compared to 0.11% (1.0) in the control group, with no significant difference between groups based on a linear regression model adjusting for clinical site (mean difference = -0.05%; 95% Confidence Interval (CI): -0.23%, 0.12%; p=0.55). Probing depth, clinical attachment loss, bleeding on probing and gingival index measures improved in the treatment group compared to the control group at six months with adjusted between-group differences of 0.33mm (95% CI: 0.26, 0.39), 0

  4. Fast growth of ultrananocrystalline diamond films by bias-enhanced nucleation and growth process in CH{sub 4}/Ar plasma

    SciTech Connect

    Saravanan, A.; Huang, B. R.; Sankaran, K. J.; Tai, N. H.; Dong, C. L.; Lin, I. N.

    2014-05-05

    This letter describes the fast growth of ultrananocrystalline diamond (UNCD) films by bias-enhanced nucleation and growth process in CH{sub 4}/Ar plasma. The UNCD grains were formed at the beginning of the film's growth without the necessity of forming the amorphous carbon interlayer, reaching a thickness of ∼380 nm in 10 min. Transmission electron microscopic investigations revealed that the application of bias voltage induced the formation of graphitic phase both in the interior and at the interface regions of UNCD films that formed interconnected paths, facilitating the transport of electrons and resulting in enhanced electron field emission properties.

  5. Fast and Low-Temperature (70 °C) Mineralization of Inkjet Printed Mesoporous TiO2 Photoanodes Using Ambient Air Plasma.

    PubMed

    Homola, Tomáš; Dzik, Petr; Veselý, Michal; Kelar, Jakub; Černák, Mirko; Weiter, Martin

    2016-12-14

    Hybrid mesoporous titania/silica electron-generating and transporting layers were prepared using wet-coating with a dispersion consisting of prefabricated titania nanoparticles and a methyl-silica binder. Titania/methyl-silica wet layers were deposited by inkjet printing and further mineralized by low-temperature atmospheric-pressure air plasma using diffuse coplanar surface barrier discharge (DCSBD) to form a titania/silica hybrid nanocomposite coating. Morphological analysis performed by scanning electron microscopy revealed no damage to the titania nanoparticles and chemical analysis performed by X-ray photoelectron spectroscopy disclosed a rapid decrease in carbon and increase in oxygen, indicating the oxidation effect of the plasma. The coatings were further electrochemically investigated with linear sweep voltammetry and chronoamperometry. The magnitude of photocurrent and photocatalytic activity were found to increase significantly with the plasma exposure on the order of 10s of seconds. The results obtained demonstrate the potential of DCSBD ambient air plasma for fast and low-temperature mineralization of titania mesoporous coatings.

  6. Identification of haemoglobin New York by haemoglobin A1c measurement using the Sebia Capillarys 2 Flex Piercing system.

    PubMed

    Chao, Yan; Wan, Zemin; Wu, Xiaobin; Qiu, Feng; Wu, Xinzhong; Wang, Yunxiu; Ke, Peifeng; Xu, Jianhua; Zhuang, Junhua; Huang, Xianzhang

    2017-01-01

    Haemoglobinopathies may interfere with the haemoglobin A1c (HbA1c) measurement, leading to incorrect diagnosis and inappropriate treatment. It is essential that HbA1c assays are capable of identifying haemoglobinopathies. We report two cases of haemoglobin New York (HbNY) discovered through HbA1c analysis using capillary electrophoresis (Capillarys 2 Flex Piercing [C2FP], Sebia). We used these samples to evaluate the ability of three other HbA1c assays to identify this variant: ion-exchange high-performance liquid chromatography (Variant II Turbo [VII-T], Bio-Rad); boronate affinity high-performance liquid chromatography (Ultra(2), Trinity Biotech) and immunoassay (Cobas c501 Tina-quant Generation 3, Roche Diagnostics). Each method was used for HbA1c assay of in samples from two cases of heterozygous haemoglobinopathy: β(0)-thalassemia/HbNY (Case 1) and HbA/NY (Case 2). Only the C2FP system detected HbNY (an additional peak appeared between HbA1c and HbA0). Clinical laboratories should be aware of the limitations of their HbA1c assay methods especially in geographic areas, where haemoglobinopathy prevalence is high.

  7. [Evaluation of HbA1c using different methods in haemoglobin variant, Hb J-Bangkok].

    PubMed

    Sawaragi, Wakana; Shibuya, Hitoshi; Yasuda, Keiko; Suzuki, Haruki; Shimizu, Chikara; Matsuno, Kazuhiko

    2009-05-01

    A 31-year-old Japanese man with haemoglobin variant, Hb J-Bangkok [beta56 (D7) Gly-->Asp], was found by discrepant values between HbA1c and glycated-albumin. We measured HbA1c using three different methods, HPLC, enzyme assay and turbidimetric immunoassay. HbA1c value measured by HPLC was much lower than those by others. Furthermore, we estimated calculated glyco-haemoglobin value measured by high-resolution HPLC, revealing that HbA1c values measured by enzyme assay and turbidimetric immunoassay were comparable with calculated value. When measuring HbA1c value in haemoglobin variant, Hb J Bangkok, enzyme assay and turbidimetric immunoassay are useful methods.

  8. HbA1c for the diagnosis of diabetes mellitus in a developing country. A position article.

    PubMed

    Gomez-Perez, Francisco J; Aguilar-Salinas, Carlos A; Almeda-Valdes, Paloma; Cuevas-Ramos, Daniel; Lerman Garber, Israel; Rull, Juan A

    2010-05-01

    An Expert Committee of the American Diabetes Association and the European Association for the Study of Diabetes recommended a move to the use of HbA1c level to diagnose diabetes mellitus. Diagnosis should be made if the A1c level is > or = 6.5%. HbA1c provides a reliable measure of chronic glycemia, correlates well with the risk of long-term diabetes complications and technical limitations for standardization have been overcome in laboratories of the U.S. and Europe. The objective of this paper is to analyze critically the advantages and disadvantages of the use of HbA1c as a diagnostic method of diabetes in a developing country. The lack of a universal threshold for the diagnosis of diabetes, the cost of the test and the absence of the standardization network in the majority of the countries are major arguments for not including HbA1c as diagnostic criteria of diabetes. HbA1c diagnostic criteria has a low sensitivity. As a result, there is a lack of agreement between the HbA1c criteria with the other diagnostic methods that lead into significant variations in the number of affected cases. In addition, sensitivity and specificity vary among ethnic groups. No study has compared the diagnostic properties of the HbA1c in Latin America. In conclusion, the logistic limitations that exist in a large proportion of developing countries and the unsolved uncertainties that exist for the definition of the A1c criterion are strong arguments against the inclusion of HbA1c among the diagnostic criteria of diabetes.

  9. Effects of plant stanol ester consumption on fasting plasma oxy(phyto)sterol concentrations as related to fecal microbiota characteristics.

    PubMed

    Baumgartner, Sabine; Mensink, Ronald P; Smet, Els De; Konings, Maurice; Fuentes, Susana; de Vos, Willem M; Plat, Jogchum

    2016-03-03

    Information regarding dietary effects on plasma oxyphytosterol concentrations as well as on the origin of oxyphytosterols is scarce. We hypothesized that plant sterols are oxidized in the intestinal lumen, mediated by microbial activity, followed by uptake into the circulation. To address this hypothesis, we carried out, a randomized, double blind, crossover study in 13 healthy subjects, who consumed for 3 weeks control and plant stanol ester enriched margarines (3.0g/d plant stanols) separated by a 4-week wash-out period. Plasma oxy(phyto)sterols were determined via GC-MS/MS, while microbiota analyses were performed on fecal DNA using a phylogenetic microarray to assess microbial composition and diversity. Plasma plant sterol concentrations did not correlate with plasma oxyphytosterols concentrations at baseline. Plant stanol consumption reduced serum sitosterol and campesterol concentrations (-37% and -38%), respectively (p<0.001), as well as plasma concentrations of 7β-OH-campesterol (-24%; p<0.05), 7β-OH-sitosterol (-17%; p<0.05) and 7-keto-sitosterol (-13%; p<0.05). Although the intestinal microbiota composition and diversity of the faecal contents were not different between the two periods, we observed significant correlations between several specific bacterial groups and plasma plant sterol, but not with plasma oxyphytosterol concentrations. In conclusion, plant stanol ester consumption reduced serum plant sterol and plasma oxyphytosterol concentrations, while intestinal microbiota composition and diversity were not changed. To definitely answer the effects of microbiota on oxyphytosterol formation, future studies could examine oxyphytosterol concentrations after changing intestinal microbial composition or by measuring intestinal oxyphytosterol formation after providing labelled non-oxidized plant sterols.

  10. Transient effects in beam-plasma interactions in a space simulation chamber stimulated by a fast pulse electron gun

    NASA Technical Reports Server (NTRS)

    Raitt, W. J.; Banks, P. M.; Denig, W. F.; Anderson, H. R.

    1982-01-01

    Interest in the interaction of electron beams with plasma generated by ionization caused by the primary electron beam was stimulated by the need to develop special vacuum tubes to operate in the kMHz frequency region. The experiments of Getty and Smullin (1963) indicated that the interaction of an energetic electron beam with its self-produced plasma resulted in the emission of wave energy over a wide range of frequencies associated with cyclotron and longitudinal plasma instabilities. This enhanced the thermal plasma density in the vicinity of the beam, and the term Beam-Plasma Discharge (BPD) was employed to described this phenomenon. The present investigation is concerned with some of the transient phenomena associated with wave emission during the beam switch-on and switch-off periods. Results are presented on the changes in electron energy spectra on a time scale of tens of milliseconds following beam switch-on. The results are discussed in terms of the beam plasma discharge phenomenon.

  11. Serum calcium is positively correlated with fasting plasma glucose and insulin resistance, independent of parathyroid hormone, in male patients with type 2 diabetes mellitus.

    PubMed

    Yamaguchi, Toru; Kanazawa, Ippei; Takaoka, Shin; Sugimoto, Toshitsugu

    2011-09-01

    Patients with primary hyperparathyroidism have impaired glucose tolerance more often than do controls, and parathyroid resection sometimes improves this derangement. However, it is unclear whether serum calcium (Ca) or parathyroid hormone (PTH) is more strongly related to impaired glucose metabolism in subjects without primary hyperparathyroidism. In this cross-sectional study, we examined patients with type 2 diabetes mellitus (DM) (271 men and 209 women) and analyzed the relationships between serum concentrations of Ca or intact PTH and DM-related variables. Simple regression analyses showed that the level of serum Ca was significantly and positively correlated with the levels of fasting plasma glucose, immunoreactive insulin, and homeostasis model assessment insulin resistance in men (P < .05), but not in women. In contrast, intact PTH was not significantly correlated with DM-related parameters in either sex. Multiple regression analyses showed that the significant and positive correlations between serum Ca vs fasting plasma glucose and homeostasis model assessment insulin resistance in men still remained after adjustment for intact PTH as well as age, body weight, height, creatinine, albumin, phosphate, bone metabolic markers, and estradiol (P < .05). Serum Ca level is positively associated with impaired glucose metabolism, independent of PTH or bone metabolism, in men with type 2 DM.

  12. BIOMARKERS IN DIABETES: HEMOGLOBIN A1c, VASCULAR AND TISSUE MARKERS

    PubMed Central

    Lyons, Timothy J; Basu, Arpita

    2012-01-01

    Biomarkers are conventionally defined as ‘biological molecules that represent health and disease states.’ They typically are measured in readily available body fluids (blood or urine), lie outside the causal pathway, are able to detect sub-clinical disease, and are used to monitor clinical and sub-clinical disease burden and response to treatments. Biomarkers can be “direct” endpoints of the disease itself, or “indirect” or surrogate endpoints. New technologies (such as metabolomics, proteomics, genomics) bring a wealth of opportunity to develop new biomarkers. Other new technologies enable the development of non-molecular, functional or bio-physical tissue-based biomarkers. Diabetes mellitus is a complex disease affecting almost every tissue and organ system, with metabolic ramifications extending far beyond impaired glucose metabolism. Biomarkers may reflect the presence and severity of hyperglycemia (i.e. diabetes itself), or the presence and severity of the vascular complications of diabetes. Illustrative examples are considered in this brief review. In blood, hemoglobin A1c (HbA1c) may be considered as a biomarker for the presence and severity of hyperglycemia, implying diabetes or pre-diabetes, or, over time, as a “biomarker for a risk factor”, i.e. hyperglycemia as a risk factor for diabetic retinopathy, nephropathy, and other vascular complications of diabetes. In tissues, glycation and oxidative stress resulting from hyperglycemia and dyslipidemia lead to widespread modification of biomolecules by advanced glycation end products (AGEs). Some of these altered species may serve as biomarkers, whereas others may lie in the causal pathway for vascular damage. New non-invasive technologies can detect tissue damage mediated by AGE formation: these include indirect measures such as pulse wave analysis (a marker of vascular dysfunction) and more direct markers such as skin autofluorescence (a marker of long-term accumulation of AGEs). In the future

  13. Description of the plasma diagnostics package (PDP) for the OSS-1 Shuttle mission and JSC plasma chamber test in conjunction with the fast pulse electron gun (FPEG)

    NASA Technical Reports Server (NTRS)

    Shawhan, S. D.

    1982-01-01

    The objectives, equipment, and techniques for the plasma diagnostics package (PDP) carried by the OSS-1 instrument payload of the STS-4 and scheduled for the Spacelab-2 mission are described. The goals of the first flight were to examine the Orbiter-magnetoplasma interactions by measuring the electric and magnetic field strengths, the ionized particle wakes, and the generated waves. The RMS was employed to lift the unit out of the bay in order to allow characterization of the fields, EM interference, and plasma contamination within 15 m of the Orbiter. The PDP will also be used to examine plasma depletion, chemical reaction rates, waves, and energized plasma produced by firing of the Orbiter thrusters. Operation of the PDP was carried out in the NASA Space Environment Simulation Laboratory test chamber, where the PDP was used to assay the fields, fluxes, wave amplitudes, and particle energy spectra. The PDP instrumentation is also capable of detecting thermal ions, thermal electrons suprathermal particles, VHF/UHF EMI levels, and the S-band field strength.

  14. Energy- and time-resolved measurements of fast ions emitted from plasma-focus discharges by means of a Thomson spectrometer

    NASA Astrophysics Data System (ADS)

    Kwiatkowski, R.; Czaus, K.; Paduch, M.; Sadowski, M. J.; Skladnik-Sadowska, E.; Zaloga, D. R.; Zielinska, E.; Żebrowski, J.

    2015-09-01

    The paper presents results of time-resolved measurements of fast deuterons emitted from high-current discharges of the Plasma-Focus (PF) type. The measurements were performed in a modified PF-1000U facility which is operated at the IFPiLM in Warsaw, Poland. The device was equipped with a fast-acting gas valve placed inside the inner electrode and oriented along the z-axis. The valve could inject a small volume of a chosen gas in front of this electrode. The PF discharges were initiated at the initial deuterium pressure equal to 1.6 or 2 hPa, with or without the use of the gas-puffing. Such discharges emitted intense beams of accelerated primary ions and X-ray pulses as well as products of nuclear fusion reactions. The reported measurements of the fast ion beams were performed by means of a Thomson-type spectrometer located at a chosen distance at the z-axis and equipped with miniature scintillation detectors. These detectors were placed in different points upon the deuteron parabola which corresponded to determined energy values. The detectors configuration allowed us to determine instants of the ion emission (using a TOF technique) and to compare them with instants of the X-ray emission. The collected data provided important information about emission characteristics of the modified PF-1000U facility.

  15. A high-legume low-glycemic index diet reduces fasting plasma leptin in middle-aged insulin-resistant and -sensitive men

    PubMed Central

    Zhang, Z; Lanza, E; Ross, AC; Albert, PS; Colburn, NH; Rovine, MJ; Bagshaw, D; Ulbrecht, JS; Hartman, TJ

    2012-01-01

    Fasting leptin and ghrelin levels were measured in 36 insulin-sensitive (IS) and 28 insulin-resistant (IR) men who consumed a legume-enriched low-glycemic index (LG) diet or healthy American (HA) diet in a randomly ordered cross-over feeding study consisting of two 4-week periods. Weight remained stable over the entire study. Fasting plasma leptin was significantly reduced from pre-study levels by both the LG (18.8%, P<0.001) and HA (16.1%, P<0.001) diets, whereas fasting ghrelin did not change. By subgroup analysis according to prestudy insulin status, leptin was reduced in IR subjects after both the LG (17.1%, P<0.01) and the HA (33.3%, P<0.001) diets, whereas IS subjects responded only after the LG diet (23.1%, P<0.01). Thus, a legume-rich LG index diet may be a beneficial strategy for reducing circulating leptin concentrations, even under conditions of weight maintenance. PMID:21206508

  16. Effect of intake on fasting heat production, respiratory quotient and plasma metabolites measured using the washed rumen technique.

    PubMed

    Kim, D H; McLeod, K R; Koontz, A F; Foote, A P; Klotz, J L; Harmon, D L

    2015-01-01

    The objective was to investigate the effect of intake before fasting on concentrations of metabolites and hormones, respiratory quotient (RQ) and fasting heat production (HP) using the washed rumen technique and to compare these values with those from the fed state. Six Holstein steers (360±22 kg) were maintained at 21°C and fed three different energy intakes within a replicated 3×3 Latin square design with 21-day periods. Steers were fed alfalfa cubes to provide 1.0, 1.5 and 2.0×NEm during 19 days of each experimental period. Steers were placed in individual metabolism stalls fitted with indirect calorimetry head-boxes on day 20 of each experimental period (FED steers) and fed their normal meal. On day 21 of each period the reticulorumen was emptied, washed and refilled with ruminal buffer (NaCl=96; NaHCO3=24; KHCO3=30; K2HPO4=2; CaCl2=1.5; MgCl2=1.5 mmol/kg of buffer) aerated with 75% N2 and 25% CO2 before introduction to the rumen (steers were not fed; WASHED steers). Each gas exchange was measured over 24 h. HP for 1.0, 1.5 and 2.0×NEm were 479, 597 and 714 kJ/daykg0.75 (s.e.m. =16), respectively. The plateau RQ was 0.756, 0.824 and 0.860 for the 1.0, 1.5 and 2.0×NEm intakes for the FED steers, respectively. After rumen washing, fasting HP was 331, 359 and 400 kJ/daykg0.75 (s.e.m.=13) for 1.0, 1.5, and 2.0×NEm intakes before fasting, respectively. The RQ for WASHED rumen steers was 0.717, 0.710 and 0.719, respectively. Cortisol and β-hydroxybutyrate concentrations in WASHED rumen steers did not exceed threshold levels for severe energy deficit and stress as can be induced from prolonged fasting. This study demonstrates that a fasting state can be emulated using the washed rumen technique, minimizing the time required as opposed to traditional fasting methodologies, without causing a severe energy deficit and stress.

  17. Use of Activation Technique and MCNP Calculations for Measurement of Fast Neutron Spatial Distribution at the MJ Plasma Focus Device.

    NASA Astrophysics Data System (ADS)

    Bienkowska, B.; Scholz, M.; Wincel, K.; Zaręba, B.

    2008-03-01

    In this paper Plasma-Focus (PF) neutron emission properties have been studied using Monte Carlo calculations for neutron and photon transport. A Thermal Neutron Scaling Factor as a function of angular position of silver activation detectors placed around MJ Plasma Focus (PF-1000) device has been calculated. Detector responses calculated for 2.5 MeV neutrons and neutrons produced by Am-Be calibration source have been obtained .The results have shown the detector response dependence on the kind of calibration neutron source and on local geometrical/structural characteristics of the PF-1000 devices. Thus the proper calibration procedure ought to be performed for correct measurement of neutron yield within Plasma-Focus devices.

  18. Diabetes mellitus: the long way of standardization of HbA(1c) to the level of highest metrological order.

    PubMed

    Kaiser, Patricia; Reinauer, Hans

    2011-01-01

    Glycated haemoglobin (HbA(1c)) measurements are used in clinical studies and for the management of diabetic patients. Various efforts were made to standardize the HbA(1c) measurements with consensus standards and standards based on a reference measurement procedure with external calibration. According to ISO 17511 a standard should meet highest accuracy possible, have a defined uncertainty of measurement and the calibration should be traceable to SI units. For HbA(1c) this has been realized using a LC-ID-MS procedure based on the existing reference measurement procedure.

  19. Sequencing analysis of ghrelin gene 5' flanking region: relations between the sequence variants, fasting plasma total ghrelin concentrations, and body mass index.

    PubMed

    Vartiainen, Johanna; Kesäniemi, Y Antero; Ukkola, Olavi

    2006-10-01

    Ghrelin is a 28-amino-acid peptide with several functions linked to energy metabolism. Low ghrelin plasma concentrations are associated with obesity, hypertension, and type 2 diabetes mellitus, whereas high concentrations reflect states of negative energy balance. Several studies addressing the hormonal and neural regulation of ghrelin gene expression have been carried out, but the role of genetic factors in the regulation of ghrelin plasma levels remains unclear. To elucidate the role of genetic factors in the regulation of ghrelin expression, we screened 1657 nucleotides of the ghrelin gene 5' flanking region (promoter and possible regulatory sites) for new sequential variations from patient samples with low (n = 50) and high (n = 50) fasting plasma total ghrelin concentrations (low- and high-ghrelin groups). Eleven single nucleotide polymorphisms (SNPs), 3 of which were rare variants (allelic frequency less than 1%) were found in our population. The genotype distribution patterns of the SNPs did not differ between the study groups, except for SNP-501A>C (P = .039). In addition, the SNP-01A>C was associated with body mass index (BMI) (P = .018). This variant was studied further in our large and well-defined Oulu Project Elucidating Risk for Atherosclerosis (OPERA) cohort (n = 1045) by the restriction fragment length polymorphism (RFLP) technique. No significant association of SNP-501A>C genotypes with fasting ghrelin plasma concentrations was found in the whole OPERA population. However, the association of this SNP with BMI and with waist circumference reached statistical significance in OPERA (P = .047 and .049, respectively), remaining of borderline significance for BMI after adjustments (P = .055). The results indicate that factors other than the 11 SNPs found in this study in the 5' flanking region of ghrelin gene are the main determinants of ghrelin plasma levels. However, SNP-501 A>C genotype distribution seems to be different in subjects having the highest

  20. Fast incorporation of primary amine group into polylactide surface for improving C₂C₁₂ cell proliferation using nitrogen-based atmospheric-pressure plasma jets.

    PubMed

    Yang, Yi-Wei; Wu, Jane-Yii; Liu, Chih-Tung; Liao, Guo-Chun; Huang, Hsuan-Yu; Hsu, Ray-Quen; Chiang, Ming-Hung; Wu, Jong-Shinn

    2014-01-01

    In this article, we report the development of the fast incorporation of primary amine functional groups into a polylactide (PLA) surface using the post-discharge jet region of an atmospheric-pressure nitrogen-based dielectric barrier discharge (DBD). Plasma treatments were carried out in two sequential steps: (1) nitrogen with 0.1% oxygen addition, and (2) nitrogen with 5% ammonia addition. The analyses show that the concentration of N/C ratio, surface energy, contact angle, and surface roughness of the treated PLA surface can reach 19.1%, 70.5 mJ/m(2), 38° and 73.22 nm, respectively. In addition, the proposed two-step plasma treatment procedure can produce a PLA surface exhibiting almost the same C2C12 cell attachment and proliferation performance as that of the conventional gelatin coating method. Most importantly, the processing/preparation time is reduced from 13-15 h (gelatin coating method) to 5-15 min (two-step plasma treatment), which is very useful in practical applications.

  1. Experimental observation of beta-induced Alfvén eigenmodes during strong tearing modes on the EAST tokamak in fast-electron plasmas

    NASA Astrophysics Data System (ADS)

    Xu, M.; Chen, W.; Hu, L. Q.; Zhou, R. J.; Zhong, G. Q.; Shi, T. H.; Xu, L. Q.; Zhang, Y.; Sun, Y. W.; Lin, S. Y.; Shen, B.; the EAST Team

    2013-06-01

    Beta-induced Alfvén eigenmodes (BAEs) during strong tearing modes are investigated on the EAST tokamak systematically, and the relation between the BAE frequencies and plasma parameters such as electron density \\bar{n}_e , ion temperature Ti, the profile of safety factor q(ρ) or the intensity of \\dot{B}_\\theta (the width of the magnetic island w) is given in detail during the injection of the power of lower hybrid wave (LHW) (or is also accompanied by the injection of ion cyclotron resonance frequency) comprehensively. All the conditions show that the values of BAE frequencies f_BAE \\propto (T_\\rme + \\frac{7}{4} T_\\rmi)^{1/2} are in agreement with the generalized fishbone-like dispersion relation, and the activities of the BAEs have a strong interaction with the process of magnetic reconnection. The BAEs are formed during the injection of the power of LHW, and disappear immediately when the power of LHW is turned off on the EAST tokamak. The LHW plasmas or the runaway discharge in Ohmic plasmas can increase the population of fast electrons, which plays a role in the activities of BAEs and a possible excitation mechanism for the BAEs during the strong tearing mode activities.

  2. Reconstruction of distribution functions of fast ions and runaway electrons in fusion plasmas using gamma-ray spectrometry with applications to ITER

    NASA Astrophysics Data System (ADS)

    Shevelev, A. E.; Khilkevitch, E. M.; Kiptily, V. G.; Chugunov, I. N.; Gin, D. B.; Doinikov, D. N.; Naidenov, V. O.; Litvinov, A. E.; Polunovskii, I. A.; Contributors, JET-EFDA

    2013-12-01

    Gamma-ray spectrometry on ITER can provide information both on confined fusion alpha particles for optimization of plasma heating and runaway electrons, which is important for safe reactor operations. For the purpose of deconvolution of gamma-ray spectra recorded in fusion plasma experiments the DeGaSum code has been developed. The code can be applied for processing of both spectra of monoenergetic gamma rays, which are born in nuclear reactions produced by alpha particles and other fast ions, and continuous bremsstrahlung spectra generated by runaway electrons in the MeV range in the plasma and reactor structure materials. Gamma-ray spectrometer response functions and bremsstrahlung spectra generated by electrons in the MeV energy range are calculated and used in the DeGaSum code. The deconvolution of the discrete spectra allows the identification of nuclear reactions, which give rise to gamma rays, and the calculation of their intensities. By applying the code for continuous hard x-ray spectra, the runaway electron energy distribution can be inferred. It can provide the maximal energy of runaway electrons with accuracy, which satisfies the ITER project requirements. The code has been used for processing of spectra recorded in JET experiments. An application of the deconvolution technique for gamma-ray emission measurements on ITER is discussed.

  3. Quantification of sofosbuvir and ledipasvir in human plasma by UPLC-MS/MS method: Application to fasting and fed bioequivalence studies.

    PubMed

    Rezk, Mamdouh R; Bendas, Ehab R; Basalious, Emad B; Karim, Iman A

    2016-08-15

    A rapid and sensitive LC-MS/MS method was developed, optimized and validated for quantification of sofosbuvir (SF) and ledipasvir (LD) in human plasma using eplerenone as an internal standard (IS). Analytes and IS were extracted from plasma by simple liquid-liquid extraction technique using methyl tertiary butyl ether. The prepared samples were chromatographed on Acquity UPLC BEH C18 column. Separation was done using a mobile phase formed of 0.1% formic acid and acetonitrile (50:50, v/v) in an isocratic mode at a flow rate of 0.4ml/min. The Xevo TQD LC-MS/MS was operated under the multiple-reaction monitoring mode using electrospray ionization. A full validation of the method was performed according to the FDA guidelines. Linearity was found to be in the range of 0.25-3500ng/ml for SF and 5-2000ng/ml for LD. The intra-day and inter-day precision and accuracy results were within the acceptable limits. A short run time of 2min allows analysis of more than 400 plasma samples per day. The developed method was successfully applied to both fasting and fed bioequivalence studies in healthy human volunteers.

  4. Development of an x-ray Talbot-Lau moire deflectometer for fast density profile measurements of dense plasmas generated by beam-target interactions

    SciTech Connect

    Clayton, Dan; Berninger, M; Meidinger, A; Stutman, Dan; Valdivia, Maria Pia

    2015-05-01

    For the first time an x-ray Talbot-Lau moire deflectometer is being developed that will use a flash tube source and fast detector for dynamic density gradient measurements. In Talbot-Lau moire deflectometry, an x-ray grating makes an image of itself on a second grating (the Talbot effect) to produce a moire pattern on a detector. The test object is placed between these gratings, with variations in index of refraction changing the pattern. A third grating in front of an incoherent x-ray source produces an array of coherent sources. With a 150 kV x-ray flash tube as the source, the gratings are placed in a glancing angle setup for performance at ~60 keV. The detector is a gated CCD with a fast scintillator for x-ray conversion. This diagnostic, designed for the Dual-Axis Radiographic Hydrodynamic Test facility (DARHT) at Los Alamos National Laboratory, measures the density profile of dense plasma plumes ejected from beam-target interactions. DARHT has two high-current, pulsed, inductive linear electron accelerators with bremsstrahlung targets at the end of each beam line to create 2-D radiographic images of hydrodynamic tests. One multi-pulse accelerator has up to four beam pulses striking the same target within 2 μs. Computer simulations that model target evolution and ejected material between pulses are used to design these targets for optimal radiographic performance; the x-ray deflectometer will directly measure density gradients in the ejected plumes and provide the first experimental constraints to these models. During the first year, currently underway, the diagnostic systems are being designed. In year two, the flash tube and fast detector will be deployed at DARHT for radiographic imaging while the deflectometer is built and tested on the bench with a continuous source. Finally, in year three, the fast deflectometer will be installed on DARHT and density measurements will be performed.

  5. Fasting Plasma Glucose as Initial Screening for Diabetes and Prediabetes in Irish Adults: The Diabetes Mellitus and Vascular Health Initiative (DMVhi)

    PubMed Central

    Sinnott, Margaret; Kinsley, Brendan T.; Jackson, Abaigeal D.; Walsh, Cathal; O’Grady, Tony; Nolan, John J.; Gaffney, Peter; Boran, Gerard; Kelleher, Cecily; Carr, Bernadette

    2015-01-01

    Objective Type 2 diabetes has a long pre clinical asymptomatic phase. Early detection may delay or arrest disease progression. The Diabetes Mellitus and Vascular health initiative (DMVhi) was initiated as a prospective longitudinal cohort study on the prevalence of undiagnosed Type 2 diabetes and prediabetes, diabetes risk and cardiovascular risk in a cohort of Irish adults aged 45-75 years. Research Design and Methods Members of the largest Irish private health insurance provider aged 45 to 75 years were invited to participate in the study. Exclusion criteria: already diagnosed with diabetes or taking oral hypoglycaemic agents. Participants completed a detailed medical questionnaire, had weight, height, waist and hip circumference and blood pressure measured. Fasting blood samples were taken for fasting plasma glucose (FPG). Those with FPG in the impaired fasting glucose (IFG) range had a 75gm oral glucose tolerance test performed. Results 122,531 subjects were invited to participate. 29,144 (24%) completed the study. The prevalence of undiagnosed diabetes was 1.8%, of impaired fasting glucose (IFG) was 7.1% and of impaired glucose tolerance (IGT) was 2.9%. Dysglycaemia increased among those aged 45-54, 55-64 and 65-75 years in both males (10.6%, 18.5%, 21.7% respectively) and females (4.3%, 8.6%, 10.9% respectively). Undiagnosed T2D, IFG and IGT were all associated with gender, age, blood pressure, BMI, abdominal obesity, family history of diabetes and triglyceride levels. Using FPG as initial screening may underestimate the prevalence of T2D in the study population. Conclusions This study is the largest screening study for diabetes and prediabetes in the Irish population. Follow up of this cohort will provide data on progression to diabetes and on cardiovascular outcomes. PMID:25874867

  6. Fast determination of paraquat in plasma and urine samples by solid-phase microextraction and gas chromatography-mass spectrometry.

    PubMed

    Gao, Lina; Liu, Junting; Wang, Chunyuan; Liu, Guojie; Niu, Xiaodong; Shu, Cuixia; Zhu, Juan

    2014-01-01

    A simple, sensitive and reliable gas chromatographic-mass spectrometric method (GC-MS) for quantifying paraquat concentration in biological samples has been developed, using ethyl paraquat as an internal standard. The method involved the procedures of sodium borohydride-nickel chloride (NaBH4-NiCl2) reduction and solid-phase microextraction (SPME) of the perhydrogenated products. GC-MS was used to identify and quantify the analytes in selected ion monitoring (SIM) mode. Under the optimal conditions, recoveries in plasma and urine samples were 94.00-99.85% and 95.00-100.34%, respectively. Excellent sample clean-up was observed and good linearities (r=0.9982 for plasma sample and 0.9987 for urine sample) were obtained in the range of 0.1-50μg/mL. The limits of detection (S/N=3) were 0.01μg/mL in plasma and urine samples. The intra-day precision was less than 8.43%, 4.19% (n=3), and inter-day precision was less than 10.90%, 10.49% (n=5) for plasma and urine samples, respectively. This method was successfully applied to the analysis of the biological samples collected from a victim who died as a result of ingestion of paraquat.

  7. Vildagliptin vs sulfonylurea in Indian Muslim diabetes patients fasting during Ramadan

    PubMed Central

    Shete, Abhijit; Shaikh, Aheson; Nayeem, K Javeed; Rodrigues, Lily; Ali, Mohamed Sheikamunadeen Sadiq; Shah, Parag; Khanna, Rajiv; Majid, Sarfaraj; Rasheed, Sabeer A; Shaikh, Shehla; Rahman, Tawfiqur

    2013-01-01

    AIM: To compare the use of vildagliptin and sulfonylurea with or without metformin in Indian Muslim patients with type 2 diabetes mellitus, fasting during Ramadan. METHODS: This was a 4-wk, multicenter, non-interventional, open-label, observational study. Incidence of hypoglycemic events (HEs), adverse events, and changes in glycosylated hemoglobin A1c (HbA1c), fasting plasma glucose, postprandial plasma glucose and body weight were measured pre- and post-Ramadan. RESULTS: Totally, 97 patients were recruited and all completed the study (vildagliptin group, n = 55; sulfonylurea group, n = 42). HEs were reported in low frequencies in both the vildagliptin and the sulfonylurea groups [0 vs 2 (4.8%) patients, respectively]. Interestingly, HbA1c reduced by -0.43% (-4.71 mmol/mol) in the vildagliptin group [8.75% (72.10 mmol/mol) to 8.32% (67.38 mmol/mol), P = 0.009] while in the sulfonylurea group there was a small increase by 0.01% [0.08 mmol/mol; 8.64% (70.92 mmol/mol) to 8.65% (71.00 mmol/mol), P = 0.958]. Higher percentage of vildagliptin-treated patients achieved HbA1c < 7.0% (< 53 mmol/mol) compared with sulfonylurea (16.4% vs 4.8%). Mean decrease in the body weight was 1.2 kg and 0.03 kg, respectively (P < 0.001). Both treatment groups were well tolerated during Ramadan. CONCLUSION: Vildagliptin is an attractive treatment option for Indian patients with type 2 diabetes mellitus who are fasting during Ramadan. PMID:24379927

  8. Long-term prognostic value of admission haemoglobin A1c (HbA1c) levels in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

    PubMed Central

    Akgul, Ozgur; Cakmak, Huseyin Altug; Erturk, Mehmet; Surgit, Ozgur; Celik, Omer; Ozturk, Derya; Uzun, Fatih; Akkaya, Emre; Yildirim, Aydın

    2014-01-01

    Introduction Many studies have reported the diagnostic and prognostic value of haemoglobin A1c (HbA1c) levels in patients with acute coronary syndrome. However, the short- and long-term prognostic value of HbA1c level in patients with ST elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI) is controversial. Aim To investigate whether admission HbA1c level has a prognostic value for in-hospital, short-, and long-term cardiovascular (CV) mortality and major adverse cardiovascular events in patients with STEMI undergoing primary PCI. Material and methods This prospective study included 443 consecutive patients with STEMI who underwent primary PCI between September 2010 and July 2012. The patients were divided into three groups based on admission HbA1c levels: group I (HbA1c ≤ 5.6%), group II (HbA1c 5.7–6.4%), and group III (HbA1c ≥ 6.5%). The in-hospital, 1-month, and 1-year CV events of all 3 patient groups were followed up. Results A significant association was found between HbA1c level and 1-year primary clinical outcomes, including CV mortality, non-fatal reinfarction, and stroke (p = 0.037). In addition, age, Killip class > 1, and left ventricular ejection fraction were found to be independent predictors of long-term CV mortality in multivariate analysis (hazard ratios (95% confidence interval) 1.081 (1.020–1.146), 4.182 (1.171–14.935), and 0.832 (0.752–0.920); p = 0.009, p = 0.028, and p < 0.001, respectively). Conclusions In this study, we demonstrated that increased admission HbA1c levels were associated with higher rates of major adverse CV events, including mortality, non-fatal reinfarction, and stroke, in patients with STEMI who underwent primary PCI. PMID:25489302

  9. Fast wave current drive

    SciTech Connect

    Goree, J.; Ono, M.; Colestock, P.; Horton, R.; McNeill, D.; Park, H.

    1985-07-01

    Fast wave current drive is demonstrated in the Princeton ACT-I toroidal device. The fast Alfven wave, in the range of high ion-cyclotron harmonics, produced 40 A of current from 1 kW of rf power coupled into the plasma by fast wave loop antenna. This wave excites a steady current by damping on the energetic tail of the electron distribution function in the same way as lower-hybrid current drive, except that fast wave current drive is appropriate for higher plasma densities.

  10. Measurement of HbA1c from stored whole blood samples in the Atherosclerosis Risk in Communities study

    PubMed Central

    SELVIN, Elizabeth; CORESH, Josef; ZHU, Hong; FOLSOM, Aaron; STEFFES, Michael W.

    2010-01-01

    Background The aims of the present study were to demonstrate the reliability of HbA1c measurements across two time periods and to compare these measurements with HbA1c distribution in the general US population. Methods HbA1c was measured in 14 069 whole blood samples in the Atherosclerosis Risk in Communities (ARIC) study using different HPLC instruments during two time periods, namely 2003–2004 and 2007–2008. At the time of measurement, samples had been in storage at –70°C for 14–18 years. To assess differences in values, HbA1c measurements were repeated in 383 samples at both periods. Indirect comparisons were made by comparing our measurements against those from a nationally representative study. Results The coefficients of variation for quality control samples were 1.8% (n = 89) in 2003–2004 and 1.4% (n = 259) in 2007–2008. The correlation between measurements at the two time points was high (r = 0.99), but with a slight bias: 0.29% points higher in 2007–2008 versus 2003–2004 (n = 383; P < 0.0001). The comparison yielded the following Deming regression equation: y(2007–2008) = 0.073+1.034x(2003–2004). After alignment using this equation, the distribution of HbA1c in the ARIC study was similar to that in the national study using fresh samples. Conclusions Measurements of HbA1c from samples stored for 14–18 years are highly reliable when using state-of-the-art HPLC instruments, but with some bias introduced over time. The HbA1c data now available in the ARIC study should be invaluable for investigations into the clinical utility of HbA1c as a diagnostic test for diabetes. PMID:20923494

  11. Subjects with Impaired Fasting Glucose: Evolution in a Period of 6 Years

    PubMed Central

    Leiva, E.; Mujica, V.; Orrego, R.; Wehinger, S.; Soto, A.; Icaza, G.; Vásquez, M.; Díaz, L.; Andrews, M.; Arredondo, M.

    2014-01-01

    Aim. To study the evolution of impaired fasting glucose (IFG), considering glucose and HbA1c levels and risk factors associated, in a period of 6 years. Methods. We studied 94 subjects with impaired fasting glucose (IFG) that were diagnosed in 2005 and followed up to 2012. Glucose and HbA1c levels were determined. A descriptive analysis of contingence charts was performed in order to study the evolution in the development of type-2 diabetes mellitus (T2DM). Results. Twenty-eight of ninety-four subjects became T2DM; 51/94 remained with IFG; and 20/94 presented normal fasting glucose. From the 28 diabetic subjects, 9 had already developed diabetes and were under treatment with oral hypoglycemic agents; 5 were diagnosed with plasma glucose < 126 mg/dL, but with HbA1c over 6.5%. In those who developed diabetes, 15/28 had a family history of T2DM in first relative degree. Also, diabetic subjects had a BMI significantly higher than nodiabetics (t test: P < 0.01). The individuals that in 2005 had the highest BMI are those who currently have diabetes. Conclusion. The IFG constitutes a condition of high risk of developing T2DM in a few years, especially over 110 mg/dL and in obesity patients. PMID:25215305

  12. Quantitative measurement of HbA1c by an immunoturbidimetric assay compared to a standard HPLC method.

    PubMed

    Hamwi, A; Schweiger, C R; Veitl, M; Schmid, R

    1995-07-01

    Determination of hemoglobin A1c (HbA1c) is one of the most important monitoring procedures for long-term control of diabetes mellitus. Several analytical methods have been developed for the measurement of glycohemoglobin (GHb). Those most frequently used are ion-exchange chromatography for HbA1c and affinity chromatography for total GHb. In this study, a new turbidimetric immunoassay for HbA1c (Boehringer Mannheim, Germany) was evaluated that was performed on a Hitachi 911 clinical chemistry analyzer (Boehringer Mannheim). Good linearity in the range of 5% to 15% HbA1c, within-run and between-run coefficients of variation ranging from 2.4% to 5.9% were obtained. Results of 179 diabetic and nondiabetic patients showed good correlation to those of a routine HPLC method (r = 0.96). In addition, HbA2, HbS, and HbF in samples from nondiabetic patients were not detected by the immunoturbimetric assay and the "labile" HbA1c fraction (Schiff base) did not interfere with the new test.

  13. What Do We Need beyond Hemoglobin A1c to Get the Complete Picture of Glycemia in People with Diabetes?

    PubMed Central

    Hinzmann, Rolf; Schlaeger, Christof; Tran, Cam Tuan

    2012-01-01

    Hemoglobin A1c (HbA1c) is currently the most commonly used marker for the determination of the glycemic status in people with diabetes and it is frequently used to guide therapy and especially medical treatment of people with diabetes. The measurement of HbA1c has reached a high level of analytical quality and, therefore, this biomarker is currently also suggested to be used for the diagnosis of diabetes. Nevertheless, it is crucial for people with diabetes and their treating physicians to be aware of possible interferences during its measurement as well as physiological or pathological factors that contribute to the HbA1c concentration without being related to glycemia, which are discussed in this review. We performed a comprehensive review of the literature based on PubMed searches on HbA1c in the treatment and diagnosis of diabetes including its most relevant limitations, glycemic variability and self-monitoring of blood glucose (SMBG). Although the high analytical quality of the HbA1c test is widely acknowledged, the clinical relevance of this marker regarding risk reduction of cardiovascular morbidity and mortality is still under debate. In this respect, we argue that glycemic variability as a further risk factor should deserve more attention in the treatment of diabetes. PMID:23055818

  14. Fast ion source and detector for investigating the interaction of turbulence with suprathermal ions in a low temperature toroidal plasma

    SciTech Connect

    Plyushchev, G.; Diallo, A.; Fasoli, A.; Furno, I.; Labit, B.; Mueller, S. H.; Podesta, M.; Poli, F. M.; Boehmer, H.; Heidbrink, W. W.; Zhang, Y.

    2006-10-15

    A specific experimental apparatus consisting of an ion source and a detector for the investigation of the interaction between suprathermal ions and drift-wave turbulence is developed on the toroidal plasma experiment. Due to the low plasma temperature ({approx}5 eV), a spatially localized, small-size ion source ({approx}4 cm) mounted inside the vacuum vessel with relatively low ion energy ({approx}100 eV-1 keV) can be used. The source consists of an aluminosilicate Li-6 ion emitter (6 mm diameter, 10-30 {mu}A current) installed on a two-dimensional (2D) poloidally moving system. The location, energy, and current density profile of the ion beam will be measured using a 2D movable gridded energy analyzer.

  15. Robust computational method for fast calculations of multicharged ions lineshapes affected by a low-frequency electrostatic plasma turbulence

    NASA Astrophysics Data System (ADS)

    Dalimier, E.; Oks, E.

    2017-01-01

    Transport phenomena in plasmas, such as, e.g., resistivity, can be affected by electrostatic turbulence that frequently occurs in various kinds of laboratory and astrophysical plasmas. Transport phenomena are affected most significantly by a low-frequency electrostatic turbulence—such as, e.g., ion acoustic waves, also known as ionic sound—causing anomalous resistivity. In this case, for computing profiles of spectral lines, emitted by plasma ions, by any appropriate code for diagnostic purposes, it is necessary to calculate the distribution of the total quasistatic field. For a practically important situation, where the average turbulent field is much greater than the characteristic ion microfield, we develop a robust computational method valid for any appropriate distribution of the ion microfield at a charged point. We show that the correction to the Rayleigh distribution of the turbulent field is controlled by the behavior of the ion microfield distribution at large fields—in distinction to the opposite (and therefore, erroneous) result in the literature. We also obtain a universal analytical expression for the correction to the Rayleigh distribution based on the asymptotic of the ion microfield distribution at large fields at a charged point. By comparison with various known distributions of the ion microfield, we show that our asymptotic formula has a sufficiently high accuracy. Also exact computations are used to verify the high accuracy of the method. This robust approximate, but accurate method yields faster computational results than the exact calculations and therefore should be important for practical situations requiring simultaneous computations of a large number of spectral lineshapes (e.g., for calculating opacities)—especially for laser-produced plasmas.

  16. Time-resolved study of the extreme-ultraviolet emission and plasma dynamics of a sub-Joule, fast capillary discharge

    NASA Astrophysics Data System (ADS)

    Valenzuela, J. C.; Wyndham, E. S.; Favre, M.

    2015-08-01

    In this work, we discuss experimental observations on the dynamics of a fast, low energy capillary discharge when operated in argon and its properties as an intense source of extreme-ultraviolet (EUV) radiation. The discharge pre-ionization and self-triggering were accomplished by the use of the hollow cathode effect. This allowed a compact size and low inductance discharge with multi-kA current level and a quarter-period of ˜10 ns at sub-Joule energy level. We used the novel moiré and schlieren diagnostics with a 12 ps laser to obtain the time evolution of the line electron density and to study the plasma dynamics. EUV spectroscopy and filtered diodes were also implemented to estimate the plasma temperature and density throughout the evolution of the discharge. EUV source size was measured by using a filtered slit-wire camera. We observed that EUV emission starts from a compressed plasma on axis during the second quarter-period of the current and continues until the fifth quarter-period. Ionization levels from Ar VII to X were observed. By comparing the EUV emission spectra with synthetic spectra, we found that at the onset of emission (˜7 ns), the plasma is well fitted by a single Maxwellian electron distribution function with Te ˜ 12 eV and ne ˜ 1017 cm-3. Close to peak emission (˜13 ns), plasma temperature and density increase to ˜20 eV and ne ˜ 1018 cm-3, respectively. However, in order to successfully match the experimental data, a two component electron distribution function was necessary. Later in time, a smaller fraction in the high energy component and higher temperature suggests homogenization of the plasma. The moiré and schlieren diagnostics showed multiple radial compression-waves merging on axis throughout the discharge; they are an important heating mechanism that leads to a period of severe turbulence at peak EUV emission. It was also observed that emission ceases when the axial maximum of the electron density collapses.

  17. Time-resolved study of the extreme-ultraviolet emission and plasma dynamics of a sub-Joule, fast capillary discharge

    SciTech Connect

    Valenzuela, J. C.; Wyndham, E. S.; Favre, M.

    2015-08-15

    In this work, we discuss experimental observations on the dynamics of a fast, low energy capillary discharge when operated in argon and its properties as an intense source of extreme-ultraviolet (EUV) radiation. The discharge pre-ionization and self-triggering were accomplished by the use of the hollow cathode effect. This allowed a compact size and low inductance discharge with multi-kA current level and a quarter-period of ∼10 ns at sub-Joule energy level. We used the novel moiré and schlieren diagnostics with a 12 ps laser to obtain the time evolution of the line electron density and to study the plasma dynamics. EUV spectroscopy and filtered diodes were also implemented to estimate the plasma temperature and density throughout the evolution of the discharge. EUV source size was measured by using a filtered slit-wire camera. We observed that EUV emission starts from a compressed plasma on axis during the second quarter-period of the current and continues until the fifth quarter-period. Ionization levels from Ar VII to X were observed. By comparing the EUV emission spectra with synthetic spectra, we found that at the onset of emission (∼7 ns), the plasma is well fitted by a single Maxwellian electron distribution function with T{sub e} ∼ 12 eV and n{sub e} ∼ 10{sup 17 }cm{sup −3}. Close to peak emission (∼13 ns), plasma temperature and density increase to ∼20 eV and n{sub e} ∼ 10{sup 18 }cm{sup −3}, respectively. However, in order to successfully match the experimental data, a two component electron distribution function was necessary. Later in time, a smaller fraction in the high energy component and higher temperature suggests homogenization of the plasma. The moiré and schlieren diagnostics showed multiple radial compression-waves merging on axis throughout the discharge; they are an important heating mechanism that leads to a period of severe turbulence at peak EUV emission. It was also observed that emission

  18. Single, community-based blood glucose readings may be a viable alternative for community surveillance of HbA1c and poor glycaemic control in people with known diabetes in resource-poor settings

    PubMed Central

    Reidpath, Daniel D.; Jahan, Nowrozy K.; Mohan, Devi; Allotey, Pascale

    2016-01-01

    Background The term HbA1c (glycated haemoglobin) is commonly used in relation to diabetes mellitus. The measure gives an indication of the average blood sugar levels over a period of weeks or months prior to testing. For most low- and middle-income countries HbA1c measurement in community surveillance is prohibitively expensive. A question arises about the possibility of using a single blood glucose measure for estimating HbA1c and therefore identifying poor glycaemic control in resource-poor settings. Design Using data from the 2011–2012 US National Health and Nutrition Examination Surveys, we examined the relationship between HbA1c and a single fasting measure of blood glucose in a non-clinical population of people with known diabetes (n=333). A linear equation for estimating HbA1c from blood glucose was developed. Appropriate blood glucose cut-off values were set for poor glycaemic control (HbA1c≥69.4 mmol/mol). Results The HbA1c and blood glucose measures were well correlated (r=0.7). Three blood glucose cut-off values were considered for classifying poor glycaemic control: 8.0, 8.9, and 11.4 mmol/L. A blood glucose of 11.4 had a specificity of 1, but poor sensitivity (0.37); 8.9 had high specificity (0.94) and moderate sensitivity (0.7); 8.0 was associated with good specificity (0.81) and sensitivity (0.75). Conclusions Where HbA1c measurement is too expensive for community surveillance, a single blood glucose measure may be a reasonable alternative. Generalising the specific results from these US data to low resource settings may not be appropriate, but the general approach is worthy of further investigation. PMID:27511810

  19. Lactation Intensity and Fasting Plasma Lipids, Lipoproteins, Non-esterified Free Fatty Acids, Leptin and Adiponectin in Postpartum Women with Recent Gestational Diabetes Mellitus: The SWIFT cohort

    PubMed Central

    Gunderson, Erica P.; Kim, Catherine; Quesenberry, Charles P.; Marcovina, Santica; Walton, David; Azevedo, Robert A.; Fox, Gary; Elmasian, Cathie; Young, Stephen; Salvador, Nora; Lum, Michael; Crites, Yvonne; Lo, Joan C.; Ning, Xian; Dewey, Kathryn G.

    2014-01-01

    Objectives Lactation may influence future progression to type 2 diabetes after gestational diabetes mellitus (GDM). However, biomarkers associated with progression to glucose intolerance have not been examined in relation to lactation intensity among postpartum women with previous GDM. This study investigates whether higher lactation intensity is related to more favorable blood lipids, lipoproteins and adipokines after GDM pregnancy independent of obesity, socio-demographics and insulin resistance. Methods The Study of Women, Infant Feeding, and Type 2 Diabetes (SWIFT) is a prospective cohort study that recruited 1,035 women diagnosed with GDM by the 3-hour 100 g oral glucose tolerance tests (OGTTs) after delivery of a live birth in 2008–2011. Research staff conducted 2-hour 75 gram OGTTs, and assessed lactation intensity, anthropometry, lifestyle behaviors and socio-demographics at 6–9 weeks postpartum (baseline). We assayed fasting plasma lipids, lipoproteins, non-esterified free fatty acids, leptin and adiponectin from stored samples obtained at 6–9 weeks postpartum for in 1,007 of the SWIFT participants who were free of diabetes at baseline. Mean biomarker concentrations were compared among lactation intensity groups using multivariable linear regression models. Results Increasing lactation intensity showed graded monotonic associations with fully adjusted mean biomarkers: 5–8% higher high-density lipoprotein cholesterol (HDL-cholesterol), 20–28% lower fasting triglycerides, 15–21% lower leptin (all trend P-values<0.01), and with 6% lower adiponectin, but only after adjustment for insulin resistance (trend P-value=0.04). Conclusion Higher lactation intensity was associated with more favorable biomarkers for type 2 diabetes, except for lower plasma adiponectin, after GDM delivery. Long-term follow-up studies are needed to assess whether these effects of lactation persist to predict progression to glucose intolerance. PMID:24931281

  20. [Determination of cefuroxime in liver-injured rat plasma by ultra fast liquid chromatography-tandem mass spectrometry via acidified protein precipitation].

    PubMed

    Zhao, Longshan; Li, Qing; Yang, Wei; He, Bosai; Wei, Binbin; Liu, Ran; Liu, Jingjing; Chen, Xiaohui; Bi, Kaishun

    2012-07-01

    In order to investigate the pharmacokinetic profiles of cefuroxime lysine, a new second generation cephalosporins, in liver-injured rat model, an ultra fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method for the determination of cefuroxime in liver-injured rat plasma was developed and validated. The plasma sample was pretreated by protein precipitation with acidified acetonitrile. The analytes were separated on a Shim-pack XR-ODS column (75 mm x 3.0 mm, 2.2 microm) with acetonitrile-0. 1% formic acid aqueous solution (40:60, v/v) as the mobile phase at a flow rate of 400 microL/min. The mass spectrometer was operated in multiple reaction monitoring (MRM) mode with a negative electrospray ionization (ESI) interface. The precursor to product ion transitions of m/z 423.2 --> 206.8 and m/z 454.1 --> 238.4 were selected to determine cefuroxime and cefotaxime (internal standard, IS), respectively. The linearities ranged from 0.01 to 1 mg/L and 1 to 400 mg/L (r > 0.99), and the limit of quantification of cefuroxime was 0.01 mg/L. The relative standard deviations (RSDs) of intra- and inter-day precisions were both less than 11.5%, and the accuracy (relative error) was between -7.1% and 2.2%. The mean extraction recovery was more than 83.5%. The total run time was 3.0 min per sample. The method is simple and fast for the preliminary pharmacokinetic study of cefuroxime lysine in liver-injured rats.

  1. A Simple and Easy Process for the Determination of Estimated Plasma Glucose Level in Patients Presenting to Hospital: An Example of Multicentric Data Mining.

    PubMed

    Serdar, Muhittin A; Koldaş, Macit; Serteser, Mustafa; Akın, Okhan; Sonmez, Cigdem; Gülbahar, Ozlem; Akbıyık, Filiz; Ünsal, Ibrahim

    2016-12-01

    The aim of the present study was to determine the relation between the simultaneous fasting plasma glucose level and HbA1c in a large population of patients presenting to the hospital, based on various measurement methods available for HbA1c. HbA1c levels of 162,210 patients presenting to various hospitals and laboratories were measured based on seven different systems, and at the same time, eAG levels were calculated based on HbA1c levels. The correlation coefficients (r) between serum plasma glucose and HbA1c levels were found to be 0.809, 0.774, 0.779, 0.817, 0.704, 0.796, and 0.747 in Bio-Rad Variant II, Tosoh G8, ADAMS A1c, Trinity Boronate Affinity, Chromsystems HPLC, Roche Tina-quant, and Abbott Architect, respectively. The concordance correlation coefficients between the eAG levels as calculated with the formulas provided in the text and the eAG levels as calculated according to NGSP directions (where eAG = (28.7*HbA1c) - 46.7) were found to be between 0.9339 and 0.9866. Despite the progress made for the standardization of HbA1c measurements, the relation between serum glucose and HbA1c still demonstrated certain discrepancies pertaining to the differences in measurement methodologies. As a conclusion, each laboratory could determine different eAG levels depending on the data originated by their individual analyzer.

  2. The Associations Between Smoking Habits and Serum Triglyceride or Hemoglobin A1c Levels Differ According to Visceral Fat Accumulation

    PubMed Central

    Koda, Michiko; Kitamura, Itsuko; Okura, Tomohiro; Otsuka, Rei; Ando, Fujiko; Shimokata, Hiroshi

    2016-01-01

    Background Whether smokers and former smokers have worse lipid profiles or glucose levels than non-smokers remains unclear. Methods The subjects were 1152 Japanese males aged 42 to 81 years. The subjects were divided according to their smoking habits (nonsmokers, former smokers, and current smokers) and their visceral fat area (VFA) (<100 cm2 and ≥100 cm2). Results The serum triglyceride (TG) levels of 835 males were assessed. In the VFA ≥100 cm2 group, a significantly greater proportion of current smokers (47.3%) exhibited TG levels of ≥150 mg/dL compared with former smokers (36.4%) and non-smokers (18.8%). The difference in TG level distribution between former smokers and non-smokers was also significant. However, among the subjects with VFA of <100 cm2, the TG levels of the three smoking habit groups did not differ. The serum hemoglobin A1c (HbA1c) levels of 877 males were also assessed. In the VFA <100 cm2 group, significantly higher proportions of current smokers (17.9%) and former smokers (14.9%) demonstrated HbA1c levels of ≥5.6% compared with non-smokers (6.3%). In contrast, in the VFA ≥100 cm2 group, significantly fewer former smokers displayed HbA1c levels of ≥5.6% compared with non-smokers and current smokers. Furthermore, the interaction between smoking habits and VFA was associated with the subjects’ TG and HbA1c concentrations, and the associations of TG and HbA1c concentrations and smoking habits varied according to VFA. Conclusions Both smoking habits and VFA exhibited associations with TG and HbA1c concentrations. The associations between smoking habits and these parameters differed according to VFA. PMID:26616395

  3. HbA1c as a Screening tool for Ketosis in Patients with Type 2 Diabetes Mellitus

    PubMed Central

    Zhu, Bing; Bu, Le; Zhang, Manna; Gusdon, Aaron M.; Zheng, Liang; Rampersad, Sharvan; Li, Jue; Qu, Shen

    2016-01-01

    Ketosis in patients with type 2 diabetes mellitus (T2DM) is overlooked due to atypical symptoms. The objective of this study is to evaluate the value of hemoglobin A1c (HbA1c) as a screening tool for ketosis in T2DM patients. This retrospective study consisted of 253 T2DM patients with ketosis at Shanghai 10th People’s Hospital during a period from January 1, 2011 to June 30, 2015. A control group consisted of 221 T2DM patients without ketosis randomly selected from inpatients during the same period. Receiver operating characteristic curve (ROC) analysis was used to examine the sensitivity and specificity of HbA1c as an indicator for ketosis. Higher HbA1c levels were correlated with ketosis. In patients with newly diagnosed T2DM, the area under the curve (AUC) was 0.832, with 95% confidence interval (CI) 0.754–0.911. The optimal threshold was 10.1% (87 mmol/mol). In patients with previously diagnosed T2DM, the AUC was 0.811 (95% CI: 0.767–0.856), with an optimal threshold of 8.6% (70 mmol/mol). HbA1c is a potential screening tool for ketosis in patients with T2DM. Ketosis is much more likely with HbA1c values at ≥10.1% in patients with newly diagnosed T2DM and HbA1c values at ≥8.6% in patients with previously diagnosed T2DM. PMID:28009017

  4. Changes in HbA1c and circulating and adipose tissue androgen levels in overweight‐obese women with polycystic ovary syndrome in response to electroacupuncture

    PubMed Central

    Maliqueo, M.; Soligo, M.; Protto, V.; Manni, L.; Jerlhag, E.; Kokosar, M.; Sazonova, A.; Behre, C. J.; Lind, M.; Ohlsson, C.; Højlund, K.; Benrick, A.

    2016-01-01

    Summary Aim Insulin sensitivity is ~40% lower in women with polycystic ovary syndrome (PCOS) than in controls. We tested the hypothesis that 5 weeks of electroacupuncture treatment improves glucose regulation and androgen levels in overweight/obese women with PCOS. Material and Methods Seventeen women with PCOS, aged 18 to 38 years, with a body mass index (BMI) ≥25 kg/m2 and diagnosed with PCOS were included in this experimental and feasibility study and subjected to five weeks of electroacupuncture treatments three times/week. The primary outcome was changes in whole‐body glucose homeostasis measured by euglycemic hyperinsulinemic clamp before and after the intervention. Secondary outcome were changes in HbA1c, circulating catecholamines, adipocyte size and adipose tissue expression of sex steroids and nerve growth factor (NGF). Results No significant change in glucose homeostasis was observed, but HbA1c decreased by 9.5% (p = 0.004), circulating testosterone decreased by 22% (p = 0.0007) and dihydrotestosterone decreased by 12% (p = 0.007). The two vagal activity markers of plasma serotonin levels and the dopamine metabolite homovanillic acid decreased by 21% (p = 0.027) and 20% (p = 0.011), respectively. Adipose tissue concentrations of testosterone decreased by 18% (p = 0.049), and androstenedione decreased by 13% (p = 0.035), and mature NGF/proNGF ratio, a marker of sympathetic activity, increased (p = 0.04). These changes occurred without changes in anthropometrics. Conclusion Five weeks of electroacupuncture treatment improves HbA1c and circulating and adipose tissue androgens in women with PCOS. This effect is mediated, at least in part, via modulation of vagal activity and adipose tissue sympathetic activity. Based on these findings, we have recently initiated a randomized controlled study (NTC02647827). PMID:28090348

  5. BEX1/ARF1A1C is required for BFA-sensitive recycling of PIN auxin transporters and auxin-mediated development in Arabidopsis.

    PubMed

    Tanaka, Hirokazu; Nodzyłski, Tomasz; Kitakura, Saeko; Feraru, Mugurel I; Sasabe, Michiko; Ishikawa, Tomomi; Kleine-Vehn, Jürgen; Kakimoto, Tatsuo; Friml, Jiři

    2014-04-01

    Correct positioning of membrane proteins is an essential process in eukaryotic organisms. The plant hormone auxin is distributed through intercellular transport and triggers various cellular responses. Auxin transporters of the PIN-FORMED (PIN) family localize asymmetrically at the plasma membrane (PM) and mediate the directional transport of auxin between cells. A fungal toxin, brefeldin A (BFA), inhibits a subset of guanine nucleotide exchange factors for ADP-ribosylation factor small GTPases (ARF GEFs) including GNOM, which plays a major role in localization of PIN1 predominantly to the basal side of the PM. The Arabidopsis genome encodes 19 ARF-related putative GTPases. However, ARF components involved in PIN1 localization have been genetically poorly defined. Using a fluorescence imaging-based forward genetic approach, we identified an Arabidopsis mutant, bfa-visualized exocytic trafficking defective1 (bex1), in which PM localization of PIN1-green fluorescent protein (GFP) as well as development is hypersensitive to BFA. We found that in bex1 a member of the ARF1 gene family, ARF1A1C, was mutated. ARF1A1C localizes to the trans-Golgi network/early endosome and Golgi apparatus, acts synergistically to BEN1/MIN7 ARF GEF and is important for PIN recycling to the PM. Consistent with the developmental importance of PIN proteins, functional interference with ARF1 resulted in an impaired auxin response gradient and various developmental defects including embryonic patterning defects and growth arrest. Our results show that ARF1A1C is essential for recycling of PIN auxin transporters and for various auxin-dependent developmental processes.

  6. Full wave simulations of fast wave efficiency and power losses in the scrape-off layer of tokamak plasmas in mid/high harmonic and minority heating regimes

    SciTech Connect

    Bertelli, N.; Jaeger, E. F.; Hosea, J. C.; Phillips, C. K.; Berry, L.; Bonoli, P. T.; Gerhardt, S. P.; Green, D.; LeBlanc, B.; Perkins, R. J.; Qin, C. M.; Pinsker, R. I.; Prater, R.; Ryan, P. M.; Taylor, G.; Valeo, E. J.; Wilson, J. R.; Wright, J. C.; Zhang, X. J.

    2015-12-17

    Here, several experiments on different machines and in different fast wave (FW) heating regimes, such as hydrogen minority heating and high harmonic fast waves (HHFW), have found strong interaction between radio-frequency (RF) waves and the scrape-off layer (SOL) region. This paper examines the propagation and the power loss in the SOL by using the full wave code AORSA, in which the edge plasma beyond the last closed flux surface (LCFS) is included in the solution domain and a collisional damping parameter is used as a proxy to represent the real, and most likely nonlinear, damping processes. 2D and 3D AORSA results for the National Spherical Torus eXperiment (NSTX) have shown a strong transition to higher SOL power losses (driven by the RF field) when the FW cut-off is removed from in front of the antenna by increasing the edge density. Here, full wave simulations have been extended for 'conventional' tokamaks with higher aspect ratios, such as the DIII-D, Alcator C-Mod, and EAST devices. DIII-D results in HHFW regime show similar behavior found in NSTX and NSTX-U, consistent with previous DIII-D experimental observations. In contrast, a different behavior has been found for C-Mod and EAST, which operate in the minority heating regime.

  7. Full wave simulations of fast wave efficiency and power losses in the scrape-off layer of tokamak plasmas in mid/high harmonic and minority heating regimes

    DOE PAGES

    Bertelli, N.; Jaeger, E. F.; Hosea, J. C.; ...

    2015-12-17

    Here, several experiments on different machines and in different fast wave (FW) heating regimes, such as hydrogen minority heating and high harmonic fast waves (HHFW), have found strong interaction between radio-frequency (RF) waves and the scrape-off layer (SOL) region. This paper examines the propagation and the power loss in the SOL by using the full wave code AORSA, in which the edge plasma beyond the last closed flux surface (LCFS) is included in the solution domain and a collisional damping parameter is used as a proxy to represent the real, and most likely nonlinear, damping processes. 2D and 3D AORSAmore » results for the National Spherical Torus eXperiment (NSTX) have shown a strong transition to higher SOL power losses (driven by the RF field) when the FW cut-off is removed from in front of the antenna by increasing the edge density. Here, full wave simulations have been extended for 'conventional' tokamaks with higher aspect ratios, such as the DIII-D, Alcator C-Mod, and EAST devices. DIII-D results in HHFW regime show similar behavior found in NSTX and NSTX-U, consistent with previous DIII-D experimental observations. In contrast, a different behavior has been found for C-Mod and EAST, which operate in the minority heating regime.« less

  8. Long-lived plasma and fast quenching of N2(C3Π u ) by electrons in the afterglow of a nanosecond capillary discharge in nitrogen

    NASA Astrophysics Data System (ADS)

    Lepikhin, N. D.; Klochko, A. V.; Popov, N. A.; Starikovskaia, S. M.

    2016-08-01

    Quenching of electronically excited nitrogen state, {{\\text{N}}2}≤ft({{\\text{C}}3}{{\\Pi}u},{{v}\\prime}=0\\right) , in the afterglow of nanosecond capillary discharge in pure nitrogen is studied. It is found experimentally that an additional collisional mechanism appears and dominates at high specific deposited energies leading to the anomalously fast quenching of the {{\\text{N}}2}≤ft({{\\text{C}}3}{{\\Pi}u}\\right) in the afterglow. On the basis of obtained experimental data and of the analysis of possible quenching agents, it is concluded that the anomalously fast deactivation of the {{\\text{N}}2}≤ft({{\\text{C}}3}{{\\Pi}u}\\right) can be explained by quenching by electrons. Long-lived plasma at time scale of hundreds nanoseconds after the end of the pulse is observed. High electron densities, about 1014 cm-3 at 27 mbar, are sustained by reactions of associative ionization. Kinetic 1D numerical modeling and comparison of calculated results with experimentally measured electric fields in the second high-voltage pulse 250 ns after the initial pulse, and electron density measurements in the afterglow confirm the validity of the suggested mechanism.

  9. Test, Construction, and Calibration of a Fast Valve Driver Unit (FVDU) and an Earth-isolated High Voltage Probe (HV probe) for a pulsed plasma experiment

    NASA Astrophysics Data System (ADS)

    Kamikawa, Yu; von der Linden, Jens; You, Setthivoine

    2013-1