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Sample records for plasma protein-a papp-a

  1. METHODS OF DETECTING PREGNANCY-ASSOCIATED PLASMA PROTEIN-A2 (PAPP-A2)

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention provides pregnancy associated plasma protein A2 (PAPP-A2), its nucleotide and amino acid sequences, antisense molecules to the nucleotide sequences which encode PAPP-A2, expression vectors for the production of purified PAPP-A2, antibodies capable of binding specifically...

  2. PREGNANCY-ASSOCIATED PLASMA PROTEIN-A2 (PAPP-A2) POLYNUCLEOTIDES

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention provides pregnancy associated plasma protein A2 (PAPP-A2), its nucleotide and amino acid sequences antisense molecules to the nucleotide sequences which encode PAPP-A2, expression vectors for the production of purified PAPP-A2, antibodies capable of binding specifically...

  3. METHODS OF DETECTING PREGNANCY-ASSOCIATED PLASMA PROTEIN-A2 (PAPP-A2)

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention provides pregnancy associated plasma protein A2 (PAPP-A2), its nucleotide and amino acid sequences, antisense molecules to the nucleotide sequences which encode PAPP-A2, expression vectors for the production of purified PAPP-A2, antibodies capable of binding specifically...

  4. Pregnancy associated plasma protein-A (PAPP-A) is not a marker of the vulnerable atherosclerotic plaque

    DEFF Research Database (Denmark)

    Iversen, Kasper; Teisner, Ane; Dalager, Soren

    2011-01-01

    To investigate if pregnancy associated plasma protein-A (PAPP-A) was present in the vulnerable plaque, and if not, to find alternative hypothesis for the release of PAPP-A.......To investigate if pregnancy associated plasma protein-A (PAPP-A) was present in the vulnerable plaque, and if not, to find alternative hypothesis for the release of PAPP-A....

  5. Pregnancy associated plasma protein-A (PAPP-A) is not a marker of the vulnerable atherosclerotic plaque

    DEFF Research Database (Denmark)

    Iversen, Kasper K; Teisner, Ane Søgaard; Dalager, Soren

    2011-01-01

    OBJECTIVE: To investigate if pregnancy associated plasma protein-A (PAPP-A) was present in the vulnerable plaque, and if not, to find alternative hypothesis for the release of PAPP-A. DESIGN AND METHODS: Vulnerable plaques and control tissues were examined by immunohistochemistry. Volunteers...

  6. Pregnancy-associated plasma protein A (PAPP-A) and preeclampsia.

    Science.gov (United States)

    Kalousová, Marta; Muravská, Alexandra; Zima, Tomás

    2014-01-01

    Pregnancy-associated plasma protein A (PAPP-A) is a key regulator of insulin-like growth factor bioavailability essential for normal fetal development. In maternal blood, this protein increases with gestational age and then rapidly decreases after delivery. It is routinely used for Down syndrome screening in the first trimester of pregnancy, and its decrease compared to a normal pregnancy indicates an increased risk for both chromosomal anomalies and adverse pregnancy outcomes. It belongs to a group of biomarkers that predict later preeclampsia development, primarily early onset preeclampsia; however, it should be combined with a Doppler ultrasonography of the uterine artery (pulsatile index) and other biochemical and maternal factors to achieve a higher detection rate with an acceptable false positivity rate. Some studies have demonstrated an even more pronounced decrease of PAPP-A in the early second trimester of pregnancy in women who subsequently develop preeclampsia compared with women who do not develop preeclampsia. Conversely, during the last trimester of pregnancy, its concentration increases even more in patients with preeclampsia than in patients without. It is also detectable at very low levels in nonpregnant individuals, and a higher concentration indicates an adverse effect in patients with acute coronary syndromes or stable atherosclerotic disease and in patients with end-stage renal disease who are being treated with hemodialysis.

  7. Pregnancy-associated plasma protein-A (PAPP-A) modulates early developmental rate in zebrafish independent of its proteolytic activity

    DEFF Research Database (Denmark)

    Kjær-Sørensen, Kasper; Engholm, Ditte Høyer; Kamei, Hiroyasu

    2013-01-01

    Pregnancy-associated plasma protein-A (PAPP-A) is a large metalloproteinase specifically cleaving IGF binding proteins, causing increased IGF bioavailability and hence local regulation of IGF receptor activation. We have identified two highly conserved zebrafish homologs of the human PAPP-A gene...

  8. Expression of recombinant murine pregnancy-associated plasma protein-A (PAPP-A) and a novel variant (PAPP-Ai) with differential proteolytic activity

    DEFF Research Database (Denmark)

    Søe, Rikke; Overgaard, Michael Toft; Thomsen, Anni R

    2002-01-01

    Murine pregnancy-associated plasma protein-A (PAPP-A) cDNA encoding a 1545 amino-acid protein has been cloned. We have also identified and cloned cDNA that encodes a novel variant of PAPP-A, PAPP-Ai, carrying a 29-residue highly basic insert. The point of insertion corresponds to a junction between...

  9. Pregnancy associated plasma protein A2 (PAPP-A2) affects bone size and shape and contributes to natural variation in postnatal growth in mice.

    Science.gov (United States)

    Christians, Julian Kenneth; de Zwaan, Devin Rhys; Fung, Sunny Ho Yeung

    2013-01-01

    Pregnancy associated plasma protein A2 (PAPP-A2) is a protease of insulin-like growth factor binding protein 5 and is receiving increasing attention for its roles in pregnancy and postnatal growth. The goals of the present study were to characterize the effects of PAPP-A2 deletion on bone size and shape in mice at 10 weeks of age, and to determine whether Pappa2 is the gene responsible for a previously-identified quantitative trait locus (QTL) contributing to natural variation in postnatal growth in mice. Mice homozygous for constitutive PAPP-A2 deletion were lighter than wild-type littermates, and had smaller mandible dimensions and shorter skull, humerus, femur, tibia, pelvic girdle, and tail bone. Furthermore, PAPP-A2 deletion reduced mandible dimensions and the lengths of the skull, femur, pelvic girdle, and tail bone more than would be expected due to the effect on body mass. In addition to its effects on bone size, PAPP-A2 deficiency also altered the shape of the mandible and pelvic girdle, as assessed by geometric morphometrics. Mice homozygous for the PAPP-A2 deletion had less deep mandibles, and pelvic girdles with a more feminine shape. Using a quantitative complementation test, we confirmed that Pappa2 is responsible for the effects of the previously-identified QTL, demonstrating that natural variation in the Pappa2 gene contributes to variation in postnatal growth in mice. If similar functional variation in the Pappa2 gene exists in other species, effects of this variation on the shape of the pelvic girdle might explain the previously-reported associations between Pappa2 SNPs and developmental dysplasia of the hip in humans, and birthing in cattle.

  10. Pattern of secretion of pregnancy-associated plasma protein-A (PAPP-A) during pregnancies complicated by fetal aneuploidy, in vivo and in vitro.

    Science.gov (United States)

    Leguy, Marie Clémence; Brun, Stephanie; Pidoux, Guillaume; Salhi, Houria; Choiset, Agnes; Menet, Marie Claude; Gil, Sophie; Tsatsaris, Vassilis; Guibourdenche, Jean

    2014-12-28

    Pregnancy-associated placental protein-A (PAPP-A) is a metalloprotease which circulates as an hetero-tetramer in maternal blood. Its maternal serum concentration in fetal trisomy 21 is decreased during the first trimester, so that PAPP-A is a useful screening biomarker. However, the regulation of PAPP-A placental secretion is unclear. We therefore investigated the secretion of PAPP-A in pregnancies complicated by fetal aneuploidies, both in vivo and in vitro. Maternal serum collected between 10 WG and 33 WG during 7014 normal pregnancies and 96 pregnancies complicated by fetal trisomy 21, 18, and 13 were assayed for PAPP-A using the Immulite 2000xpi system®. The pregnancies were monitored using ultrasound scanning, fetal karyotyping and placental analysis. Villous cytotrophoblasts were isolated from normal and trisomic placenta and cultured to investigate PAPP-A secretion in vitro (n=6). An increased nuchal translucency during the first trimester is a common feature of many chromosomal defect but each aneuploidy has its own syndromic pattern of abnormalities detectable at the prenatal ultrasound scanning and confirmed at the fetal examination thereafter. PAPP-A levels rise throughout normal pregnancy whereas in trisomy 21, PAPP-A levels were significantly decreased, but only during the first trimester. PAPP-A levels were decreased in trisomy 13 and sharply in trisomy 18, whatever the gestational age. In vitro, PAPP-A secretion was decreased in aneuploidy, and associated with decreased hCG secretion in Trisomy 21 and 18. These biochemical profiles did not appear to be linked to any specific histological lesions affecting the placenta. These profiles may reflect different quantitative and qualitative placental dysfunctions in the context of these aneuploidies.

  11. Dried blood spot measurement of pregnancy-associated plasma protein A (PAPP-A) and free beta-subunit of human chorionic gonadotropin (beta-hCG) from a low-resource setting

    NARCIS (Netherlands)

    Browne, J. L.; Schielen, P. C. J. I.; Belmouden, I.; Pennings, J. L. A.; Klipstein-Grobusch, K.

    ObjectivesThe objectives of the article is to compare pregnancy-associated plasma protein A (PAPP-A) and free -subunit of human chorionic gonadotropin (-hCG) concentrations in dried blood spots (DBSs) with serum of samples obtained from a public hospital in a low-resource setting and to evaluate

  12. Effect of pregnancy-associated plasma protein-A (PAPP-A) single-nucleotide polymorphisms on the level and activity of PAPP-A and the hormone profile in fluid from normal human small antral follicles

    DEFF Research Database (Denmark)

    Bøtkjær, Jane Alrø; Borgbo, Tanni; Kløverpris, Søren;

    2016-01-01

    Objective: To reveal a possible relationship between two single nucleotide polymorphisms (SNPs) in PAPP-A—1224 (rs7020782) and 327 (rs12375498)—and the level and activity of PAPP-A in follicular fluid (FF) of human small antral follicles, and to analyze the intrafollicular hormone levels. Design:...... of insulin-like growth factor activity is warranted. (Fertil Steril 2016;-:-–-. 2016 by American Society for Reproductive Medicine.) Key Words: Human follicles, human ovarian steroidogenesis, IGF signaling, PAPP-A, single-nucleotide polymorphisms...

  13. Effect of pregnancy-associated plasma protein-A (PAPP-A) single-nucleotide polymorphisms on the level and activity of PAPP-A and the hormone profile in fluid from normal human small antral follicles

    DEFF Research Database (Denmark)

    Bøtkjær, Jane Alrø; Borgbo, Tanni; Kløverpris, Søren

    2016-01-01

    Objective: To reveal a possible relationship between two single nucleotide polymorphisms (SNPs) in PAPP-A—1224 (rs7020782) and 327 (rs12375498)—and the level and activity of PAPP-A in follicular fluid (FF) of human small antral follicles, and to analyze the intrafollicular hormone levels. Design:...

  14. Pregnancy-associated plasma protein-A (PAPP-A) and the proform of the eosinophil major basic protein (ProMBP) are associated with increased risk of death in heart failure patients

    DEFF Research Database (Denmark)

    Dembic, Maja; Hedley, Paula L.; Torp-Pedersen, Christian

    2017-01-01

    .0001), respectively. However, neither PAPP-A nor proMBP were significant independent predictors when the model included age, gender, brain-type natriuretic peptide, medical history of HF, ischemic heart disease, chronic obstructive pulmonary disease, and diabetes mellitus. In conclusion, high levels of PAPP-A and pro......-A) is a marker of arteriosclerotic heart disease. PAPP-A is a serum protease, which is involved in the insulin-like growth factor 1 (IGF-1) axis where it is inhibited by the proform of the eosinophil major basic protein (proMBP). In this study, we evaluated serum PAPP-A and proMBP as long-term prognostic...

  15. Expression of Recombinant Pregnancy-associated Plasma Protein-A

    Institute of Scientific and Technical Information of China (English)

    CHENG; Bin-yan; LI; Zi-ying; ZHANG; Xue-feng; LIU; Yi-bing

    2013-01-01

    Pregnancy-associated plasma protein-A(PAPP-A)is producted by the syntrophoblast tissue of the placenta and decidual cells.It belongs to macromolecular glycoprotein.PAPP-A is a sensitive serum marker of Down’s syndrome and has clinical valuable in the early identification of acute coronary syndrome(ACS).According to the structure of PAPP-A,PAPP-A DNA is divided into five segments(S1-S5)for

  16. PAPP-A proteolytic activity enhances IGF bioactivity in ascites from women with ovarian carcinoma

    DEFF Research Database (Denmark)

    Thomsen, Jacob; Hjortebjerg, Rikke; Espelund, Ulrick

    2015-01-01

    Pregnancy-associated plasma protein-A (PAPP-A) stimulates insulin-like growth factor (IGF) action through proteolysis of IGF-binding protein (IGFBP)-4. In experimental animals, PAPP-A accelerates ovarian tumor growth by this mechanism. To investigate the effect of PAPP-A in humans, we compared se...

  17. Purification of Pregnancy-associated Plasma Protein-A and Preparation of Its Antibodies

    Institute of Scientific and Technical Information of China (English)

    CHENG; Bin-yan; LI; Zi-ying; YUAN; Zhi-gang; ZHANG; Xue-feng; LIU; Yi-bing

    2013-01-01

    Pregnancy-associated plasma protein-A(PAPP-A)is isolated from the plasma of pregnant women.It is producted by the syntrophoblast tissue of the placenta and decidual cells.PAPP-A belongs to macromolecular glycoprotein.As a sensitive serum marker,the decreased PAPP-A levels during the first

  18. Temporal course of pregnancy-associated plasma protein-A in angioplasty-treated ST-elevation myocardial infarction patients and potential significance of concomitant heparin administration

    DEFF Research Database (Denmark)

    Terkelsen, Christian J; Oxvig, Claus; Nørgaard, Bjarne L

    2009-01-01

    Pregnancy-associated plasma protein-A (PAPP-A) is a putative plaque instability marker. In acute coronary syndromes, the disrupted culprit plaque contains abundant PAPP-A, and circulating PAPP-A levels predict clinical outcomes. Determinants of circulating PAPP-A levels, however, are not fully...

  19. Association between PAPP-A and placental thickness

    Directory of Open Access Journals (Sweden)

    Elaheh Mesdaghi-nia

    2016-06-01

    Full Text Available Background: Measuring of maternal serum pregnancy-associated plasma protein-A (PAPP-A in first trimester can be a way for early detection of adverse prenatal outcome due to faulty placenta. Objective: The aim was to Determination of association between placental thickness in second trimester with low level of PAPP-A in first trimester. Materials and Methods: In this cohort study, serum PAPP-A of 187 pregnant women was measured in the first trimester of pregnancy. Patients who had PAPP-A ≤0.8 MOM were in exposed and others who had PAPP-A >0.8 defined as unexposed group. The criteria of placental thickness in ultrasound study was thickness of 4 cm or more than 50% of placental length. Results: Of 187 patients, 87 patients had PAPP-A >0.8 and 93 patients had PAPP-A ≤0.8. Women with low levels of PAPP-A in the first trimester, had an increased incidence placental thickness of 34.4%, whereas another group had about 15% (p=0.002. Also, PAPP-A levels had acceptable sensitivity and specificity for placental thickness detection (71.1% and 54.8%, respectively. Conclusion: Our study showed that serum level of PAPP-A generally was low (≤0.8 in women with a thick placenta (>4 cm or >50% of placental length. The first trimester of pregnancy measurement of PAPP-A will be more predictable for healthy placenta.

  20. First trimester PAPP-A2, PAPP-A and hCGβ in small-for-gestational-age pregnancies

    DEFF Research Database (Denmark)

    Hansen, Young Bae; Myrhøj, Vibeke; Jørgensen, Finn Stener;

    2015-01-01

    BACKGROUND: Pregnancy-associated plasma protein-A2 (PAPP-A2) is a recently discovered protease that cleaves a subset of insulin-like growth factor binding proteins (IGFBP). The molecular function suggests its involvement in the IGF system that is vital for fetal growth and development. Our...... objectives were to establish first trimester median curves of PAPP-A2, PAPP-A and hCGβ for singleton normal pregnancies and to investigate whether an altered level of one or more of the biomarkers is associated with small-for-gestational-age (SGA) neonates before and after stratification according...... to maternal hypertension and/or proteinuria. METHODS: This was a case-control study based on 985 pregnant women delivering normal-weighted neonates and 170 pregnant women delivering SGA neonates. PAPP-A2 was measured by ELISA. PAPP-A and hCGβ were measured by an automatic analyzer. Median curves from 8...

  1. Regulation of IGF binding protein proteolysis by pregnancy-associated plasma protein-ARegulation of IGF binding protein proteolysis by pregnancy-associated plasma protein-A

    DEFF Research Database (Denmark)

    Gaidamauskas, Ervinas

    During his PhD studies, Ervinas Gaidamauskas researched the proteins pregnancy-associated plasma protein-A (PAPP-A) and its homologue PAPP-A2 in vitro. As suggested by its name, PAPP-A plays an important role in pregnancy and fetal development. Additionally, recent studies indicate a newly...

  2. Regulation of IGF binding protein proteolysis by pregnancy-associated plasma protein-ARegulation of IGF binding protein proteolysis by pregnancy-associated plasma protein-A

    DEFF Research Database (Denmark)

    Gaidamauskas, Ervinas

    During his PhD studies, Ervinas Gaidamauskas researched the proteins pregnancy-associated plasma protein-A (PAPP-A) and its homologue PAPP-A2 in vitro. As suggested by its name, PAPP-A plays an important role in pregnancy and fetal development. Additionally, recent studies indicate a newly...

  3. Low PAPP-A in the first trimester is associated with reduced fetal growth rate prior to gestational week 20

    DEFF Research Database (Denmark)

    Salvig, J D; Kirkegaard, I; Winding, Trine Nøhr

    2010-01-01

    To evaluate the association between maternal pregnancy-associated plasma protein-A (PAPP-A) and fetal growth from the first to the second trimester.......To evaluate the association between maternal pregnancy-associated plasma protein-A (PAPP-A) and fetal growth from the first to the second trimester....

  4. Pregnancy-associated plasma protein-A, a marker for outcome in patients suspected for acute coronary syndrome

    DEFF Research Database (Denmark)

    Iversen, Kasper; Dalsgaard, Morten; Teisner, Ane S

    2010-01-01

    To examine if pregnancy-associated plasma protein-A (PAPP-A) in patients with chest pain, could identify patients at risk for death or myocardial infarction.......To examine if pregnancy-associated plasma protein-A (PAPP-A) in patients with chest pain, could identify patients at risk for death or myocardial infarction....

  5. Pregnancy-associated plasma protein-A, a marker for outcome in patients suspected for acute coronary syndrome

    DEFF Research Database (Denmark)

    Iversen, Kasper K; Dalsgaard, Morten; Teisner, Ane S;

    2010-01-01

    To examine if pregnancy-associated plasma protein-A (PAPP-A) in patients with chest pain, could identify patients at risk for death or myocardial infarction.......To examine if pregnancy-associated plasma protein-A (PAPP-A) in patients with chest pain, could identify patients at risk for death or myocardial infarction....

  6. The proteolytic activity of pregnancy-associated plasma protein-A is potentially regulated by stanniocalcin-1 and -2 during human ovarian follicle development

    DEFF Research Database (Denmark)

    Jepsen, Malene R.; Kløverpris, Søren; Bøtkjær, Jane A.

    2016-01-01

    STUDY QUESTION: Is the proteolytic activity of pregnancy-associated plasma protein-A (PAPP-A) regulated by the stanniocalcins (STC1 and STC2) during human follicle maturation? SUMMARY ANSWER: The STCs and PAPP-A show similar expression by immunohistochemistry in developing follicles, and regulation...... of PAPP-A proteolytic activity is suggested by the identification of inhibited protein complexes between PAPP-A and STC1 or STC2 in human follicular fluid (FF). WHAT IS KNOWN ALREADY: The insulin-like growth factor (IGF)-regulating proteinase PAPP-A is secreted by the granulosa cells of estrogen...

  7. Pregnancy-associated plasma protein-A and the vulnerable plaque

    DEFF Research Database (Denmark)

    Jespersen, Camilla H B; Vestergaard, Kirstine R; Schou, Morten

    2014-01-01

    For more than a decade, pregnancy-associated plasma protein-A (PAPP-A) has been examined for its relation to acute coronary syndrome (ACS) and the vulnerable plaque. This review summarizes the current knowledge of plasma PAPP-A in relation to nonpregnant individuals focusing on patients with ACS,......, discusses its use as a possible biomarker for diagnosis and prognosis in ACS, briefly describes the challenges in different assay technologies and describes the effect of heparin administration on PAPP-A concentrations in plasma....

  8. Pregnancy-associated plasma protein A in human ovarian follicles and its association with intrafollicular hormone levels

    DEFF Research Database (Denmark)

    Bøtkjær, Jane Alrø; Jeppesen, Janni Vikkelsø; Wissing, Marie Louise

    2015-01-01

    To evaluate follicular fluid (FF) levels of pregnancy-associated plasma protein A (PAPP-A) in relation to levels of intrafollicular hormones. Furthermore, immunostaining of human follicles of varying diameters was studied for PAPP-A, antimüllerian hormone (AMH), and aromatase, and the biological ...

  9. Treatment with recombinant human insulin-like growth factor-I improves growth in patients with PAPP-A2 deficiency

    DEFF Research Database (Denmark)

    Teresa Muñoz-Calvo, María; Barrios, Vicente; Pozo, Jesús;

    2016-01-01

    CONTEXT: Pregnancy-associated plasma protein-A2 (PAPP-A2) is a metalloproteinase that specifically cleaves IGFBP-3 and IGFBP-5. Mutations in the PAPP-A2 gene have recently been shown to cause postnatal growth failure in humans, with specific skeletal features, due to the resulting decrease in IGF...

  10. CRP and TNF-α  Induce PAPP-A Expression in Human Peripheral Blood Mononuclear Cells

    Directory of Open Access Journals (Sweden)

    Weiping Li

    2012-01-01

    Full Text Available Objective. The effects of C-reactive protein (CRP and tumor necrosis factor-α (TNF-α on pregnancy-associated plasma protein-A (PAPP-A expression in human peripheral blood mononuclear cells (PBMCs require further investigation. Methods. The PAPP-A levels in culture supernatants, PAPP-A mRNA expression, and cellular PAPP-A expression were measured in human PBMCs isolated from fresh blood donations provided by 6 healthy volunteers (4 donations per volunteer. Analyses were conducted by ultrasensitive ELISA, western blotting, and RT-PCR following stimulation with CRP or TNF-α cytokines. Results. PAPP-A mRNA and protein levels after CRP stimulation peaked at 24 hours, whereas peak PAPP-A mRNA and protein levels were achieved after TNF-α stimulation at only 2 and 8 hours, respectively. These findings indicate the dose-dependent effect of CRP and TNF-α stimulation. Actinomycin D treatment completely prevented CRP and TNF-α induction of PAPP-A mRNA and protein expression. Additionally, nuclear factor- (NF- κB inhibitor (BAY11-7082 potently inhibited both CRP and TNF-α stimulated PAPP-A mRNA and protein expression. Conclusions. Human PBMCs are capable of expressing PAPP-A in vitro, expression that may be regulated by CRP and TNF-α through the NF-κB pathway. This mechanism may play a significant role in the observed increase of serum PAPP-A levels in acute coronary syndrome (ACS.

  11. The value of PAPP-A in the diagnosis and prognosis of GTD

    Institute of Scientific and Technical Information of China (English)

    Jing Fang; Shu Wang; Wen-li Gou

    2007-01-01

    Objective: To investigate the value of PAPP-A (pregnancy assouated plasma protein-A) in the diagnosis and prognosis of gestational trophoblastic disease (GTD). Methods: The serum β-HCG (β-human chorionic gonadotropin) and PAPP-A levels of 25 normal pregnant women, 28 patients with complete hydatidiform mole and 38 patients with invasive mole were measured by enzyme linked immunosorbent assay (ELISA) during the periods of diagnosis, treatment and follow-up. Results: Compared with control group, patients with complete mole and invasive mole had higher levels of β-HCG (P < 0.01 ). But there was no significant difference between the complete and invasive mole group (P > 0.05). The PAPP-A level of complete mole group was significantly higher than that of control group (P < 0.01). The PAPP-A level of invasive mole group was significantly higher than that of complete mole group and control group(P < 0.05). In complete mole group, serum β-HCG and PAPP-A levels of the patients with malignant sequelae were significantly higher than those with benign sequelae (P < 0.05). The β-HCG level had no relationship with the clinical stage of invasive mole. However, the PAPP-A level increased with clinical advancement of invasive mole. The levels of β-HCG and PAPP-A gradually decreased after evacuation in patients with complete moles, but maintained positive or even increased in patients with subsequent malignancy. Conclusion: The PAPP-A level can give us some help not only in early diagnosis of hydatidiform mole and invasive mole, but also in the prognosis of malignant sequelae.

  12. Pregnancy associated plasma protein-A as a marker for myocardial infarction and death in patients with stable coronary artery disease: A prognostic study within the CLARICOR Trial

    DEFF Research Database (Denmark)

    Iversen, Kasper K; Teisner, Børge; Winkel, Per

    2011-01-01

    OBJECTIVE: Pregnancy associated plasma protein-A (PAPP-A) is a potential new marker for vulnerable plaques in the coronary arteries only examined in stable coronary disease (CAD) in patients undergoing coronary angiography. Here we address the prognostic value of serum PAPP-A in unselected stable...

  13. Stanniocalcin-1 Potently Inhibits the Proteolytic Activity of the Metalloproteinase Pregnancy-associated Plasma Protein-A

    DEFF Research Database (Denmark)

    Kløverpris, Søren; Mikkelsen, Jakob Hauge; Pedersen, Josefine Hvidkjær

    2015-01-01

    regulation in these species. Several physiological functions of STC1 have been reported, although many molecular details are still lacking. We here demonstrate that STC1 is an inhibitor of the metzincin metalloproteinase, pregnancy-associated plasma protein-A (PAPP-A), which modulates insulin-like growth...... that the homologous STC2 inhibits PAPP-A proteolytic activity, and that this depends on the formation of a covalent complex between the inhibitor and the proteinase, mediated by Cys-120 of STC2. We find that STC1 is unable to bind covalently to PAPP-A, in agreement with the absence of a corresponding cysteine residue....... It rather binds to PAPP-A with high affinity (KD = 75 pm). We further demonstrate that both STC1 and STC2 show inhibitory activity toward PAPP-A2, but not selected serine proteinases and metalloproteinases. We therefore conclude that the STCs are proteinase inhibitors, probably restricted in specificity...

  14. Optimisation of sandwich ELISA based on monoclonal antibodies for the specific measurement of pregnancy-associated plasma protein (PAPP-A) in acute coronary syndrome

    DEFF Research Database (Denmark)

    Rossen, Marie; Iversen, Kasper; Teisner, Ane

    2007-01-01

    OBJECTIVES: PAPP-A has become the principal biochemical serum marker in first trimester screening for Down syndrome, the original data being based on results of a radioimmunoassay (RIA). Recent observations using sandwich ELISA technology have proposed PAPP-A as a potential marker in patients wit...

  15. PAPP-A and IGFBP-4 fragment levels in patients with ST-elevation myocardial infarction treated with heparin and PCI

    DEFF Research Database (Denmark)

    Hjortebjerg, Rikke; Lindberg, Søren; Jensen, Jan S

    2015-01-01

    OBJECTIVES: Circulating levels of pregnancy-associated plasma protein-A (PAPP-A) predict outcome in patients with acute coronary syndrome (ACS). Unfortunately, administration of heparin to patients with ACS increases circulating PAPP-A, probably by a detachment of PAPP-A from cell surfaces......-segment elevation myocardial infarction (STEMI) treated with percutaneous coronary intervention (PCI). Prior to PCI, patients were injected with 10,000IU of unfractionated heparin (UFH). Blood samples were collected immediately before PCI, but after UFH-injection, immediately after PCI and on day 1 and day 2...

  16. Complete cDNA sequence of the preproform of human pregnancy-associated plasma protein-A. Evidence for expression in the brain and induction by cAMP

    DEFF Research Database (Denmark)

    Haaning, Jesper; Oxvig, Claus; Overgaard, Michael Toft

    1996-01-01

    A cDNA that encodes the prepropeptide of pregnancy-associated plasma protein-A (preproPAPP-A), a putative metalloproteinase, has been cloned and sequenced. PAPP-A is synthesized in the placenta as a 1627-residue precursor preproprotein with a putative 22-residue signal peptide and a highly basic ...

  17. Variation of papp-a level in the first trimester of pregnancy and its clinical outcome.

    Science.gov (United States)

    Patil, Mithil; Panchanadikar, T M; Wagh, Girija

    2014-04-01

    Abnormalities in maternal serum marker levels and fetal measurements obtained during the first trimester screening can be a marker not only for certain chromosomal disorders and anomalies in the fetus but also for specific pregnancy complications. In particular, low maternal serum pregnancy-associated plasma protein-A (PAPP-A), at 11-13 weeks of gestation, is associated with stillbirth, infant death, intrauterine growth restriction, preterm birth, and pre-eclampsia in chromosomally normal fetuses, while a raised nuchal translucency is associated with specific structural abnormalities and genetic syndromes. We have studied the serum Papp-A level in 560 pregnant patients (11-13 weeks gestation) registered at Bharati Hospital and Research Centre, Pune. All patients undergoing testing were followed till the delivery and their neonatal outcome was also taken into consideration. Our aim is to study the pregnancy outcome in relation to the variations of Papp-A level in the first trimester of pregnancy. Every patient visiting the antenatal OPD was counseled for testing of First Trimester Screening to assess fetal well-being. Patients who were registered for delivery at our hospital were taken into the trial. Blood samples were taken at 11-13 weeks of pregnancy and sent to the PerkinElmer lab for analysis. Results were expressed in Multiple of Median and patients having MOM value less than 0.5 were carefully observed till the delivery, and a thorough neonatal examination was done by a pediatrician. 524 patients were included in the trial out of which 452 patients were found to have a normal Papp-A level of >0.5 MOM. All these patients were followed further during the antenatal period where 18 patients developed preterm labor and few patients developed pregnancy-induced hypertension. The obstetric outcome of patients with a normal Papp-A level was fairly uneventful as compared to others with a low Papp-A level. Though Papp-A level in the first trimester of pregnancy (11

  18. Analysis of Pregnancy-Associated Plasma Protein A Production in Human Adult Cardiac Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Piera D’Elia

    2013-01-01

    Full Text Available IGF-binding proteins (IGFBPs and their proteases regulate IGFs bioavailability in multiple tissues. Pregnancy-associated plasma protein A (PAPP-A is a protease acting by cleaving IGFBP2, 4, and 5, regulating local bioavailability of IGFs. We have previously shown that IGFs and IGFBPs are produced by human adult cardiac progenitor cells (haCPCs and that IGF-1 exerts paracrine therapeutic effects in cardiac cell therapy with CPCs. Using immunofluorescence and enzyme immunoassays, we firstly report that PAPP-A is produced and secreted in surprisingly high amounts by haCPCs. In particular, the homodimeric, enzymatically active, PAPP-A is secreted in relevant concentrations in haCPC-conditioned media, while the enzymatically inactive PAPPA/proMBP complex is not detectable in the same media. Furthermore, we show that both homodimeric PAPP-A and proMBP can be detected as cell associated, suggesting that the previously described complex formation at the cell surface does not occur easily, thus positively affecting IGF signalling. Therefore, our results strongly support the importance of PAPP-A for the IGFs/IGFBPs/PAPP-A axis in CPCs biology.

  19. Pregnancy associated plasma protein A, a novel, quick, and sensitive marker in ST-elevation myocardial infarction

    DEFF Research Database (Denmark)

    Iversen, Kasper K; Teisner, Ane S; Teisner, Børge

    2008-01-01

    Traditional biomarkers in acute coronary syndromes reflect myocardial necrosis but not the underlying arteriosclerotic disease. Pregnancy-associated plasma protein A (PAPP-A) is a new biomarker in acute coronary syndromes that detects vulnerable plaques in arteriosclerotic disease and identifies ...

  20. The effect of heparin on pregnancy associated plasma protein-A concentration in healthy, non-pregnant individuals

    DEFF Research Database (Denmark)

    Jespersen, Camilla H B; Vestergaard, Kirstine R; Schou, Morten

    2015-01-01

    OBJECTIVES: The objective of this study was to determine the differences in pregnancy associated plasma protein-A (PAPP-A) concentrations in heparin naive and heparin treated healthy men and non-pregnant women, to find a possible difference in different age groups, and to determine the response...

  1. Autocorrelation and cross-correlation between hCGβ and PAPP-A in repeated sampling during first trimester of pregnancy

    DEFF Research Database (Denmark)

    Nørgaard, Pernille; Wright, Dave; Ball, Susan;

    2013-01-01

    Theoretically, repeated sampling of free β-human chorionic gonadotropin (hCGβ) and pregnancy associated plasma protein-A (PAPP-A) in the first trimester of pregnancy might improve performance of risk assessment of trisomy 21 (T21). To assess the performance of a screening test involving repeated...

  2. [Association between IGF system and PAPP-A in coronary atherosclerosis].

    Science.gov (United States)

    Fierro-Macías, Alfonso Eduardo; Floriano-Sánchez, Esaú; Mena-Burciaga, Victoria Michelle; Gutiérrez-Leonard, Hugo; Lara-Padilla, Eleazar; Abarca-Rojano, Edgar; Fierro-Almanzán, Alfonso Edmundo

    2016-01-01

    Atherosclerosis is a condition that involves multiple pathophysiological mechanisms and whose knowledge has not been fully elucidated. Often, scientific advances on the atherogenic pathophysiology generate that molecules not previously considered in the scene of this disease, were attributed actions on the onset or progression of it. A representative example is the study of a new mechanism involved in the atherogenic process, consisting of the association between the insulin-like growth factor (IGF) system and pregnancy-associated plasma protein-A (PAPP-A). Insulin-like growth factor system is a family of peptides that include 3 peptide hormones, 4 transmembrane receptors and 6 binding proteins. Insulin-like growth factor-1 (IGF-1) is the main ligand of the IGF system involved in coronary atherosclerosis. IGF-1 exerts its effects via activation of the IGF-1R receptor on vascular smooth muscle cells or macrophages. In vascular smooth muscle cells promotes migration and prevents apoptosis which increases plaque stability while in macrophages reduces reverse cholesterol transport leading to the formation of foam cells. Regulation of IGF-1 endothelial bioavailability is carried out by IGFBP proteases, mainly by PAPP-A. In this review, we address the mechanisms between IGF system and PAPP-A in atherosclerosis with emphasis on molecular effects on vascular smooth muscle cells and macrophages.

  3. First trimester pregnancy-associated plasma protein A and human chorionic gonadotropin-beta in early and late pre-eclampsia

    DEFF Research Database (Denmark)

    Karahasanovic, Azra; Sørensen, Steen; Nilas, Lisbeth

    2014-01-01

    Abstract Background: The aim of this study was to compare pregnancy-associated plasma protein A (PAPP-A) and the β-subunit of human chorionic gonadotropin (hCGβ) measured in maternal plasma at the first trimester screening, in women who later developed early or late pre-eclampsia (PE) to women...

  4. Temporal effects of maternal and pregnancy characteristics on serum PAPP-A and free β-hCG at 7-14 weeks' gestation

    DEFF Research Database (Denmark)

    Ball, Susan; Ekelund, Charlotte; Wright, Dave

    2013-01-01

    Objective: Investigate gestational age dependent effects of racial origin, smoking status and mode of conception on maternal serum levels of free ß-human chorionic gonadotropin (β-hCG) and pregnancy associated plasma protein-A (PAPP-A) at 7-14 weeks' gestation. Methods: Data arise from prospective......-hCG and PAPP-A concentrations at 7-14 weeks are affected by several pregnancy characteristics. The effects of Afro-Caribbean race, smoking and IVF conception change with gestational age. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd....... first-trimester combined screening for aneuploidies in singleton pregnancies, with serum free ß-hCG and PAPP-A measured at 7(+1) -14(+3) weeks' gestation. We include 27,908 pregnancies from three centres in the UK and 125,461 pregnancies from 22 centres in Denmark with normal fetal karyotype or birth...

  5. Serum pregnancy-associated plasma protein A correlates with inflammation and malnutrition in patients treated with maintenance hemodialysis.

    Science.gov (United States)

    Mazur-Laskowska, Małgorzata; Bała-Błądzińska, Agnieszka; Zegartowska, Paulina; Dumnicka, Paulina; Ząbek-Adamska, Anna; Kapusta, Maria; Maleszka, Aleksandra; Maziarz, Barbara; Kuźniewski, Marek; Kuśnierz-Cabala, Beata

    2015-01-01

    Advanced chronic kidney disease (CKD) leads to complications such as anemia, electrolyte abnormalities, bone and mineral disorder, and malnutrition-inflammation-atherosclerosis (MIA) syndrome, that result in high cardiovascu- lar mortality. One of the biomarkers associated with inflammation and cardiovascular events is pregnancy-associated plasma protein A (PAPP-A). The aim of the study was to measure serum PAPP-A in hemodialyzed CKD patients, and to investigate its correlations with the laboratory markers of the complications. We enrolled 78 consecutive stable adult CKD patients treated with maintenance hemodialysis for median period of 60 months. PAPP-A concentrations were measured with by electrochemiluminescence immunoassay. Average serum PAPP-A in hemodialyzed patients was almost two times higher than the upper reference limit. It positively correlated with N-terminal pro-brain natriuretic peptide (NT-proBNP), serum sodium, and the markers of inflammation and malnutrition. In conclusion, serum PAPP-A seems a useful biomarker associated with cardiovascular dysfunction, inflammatory state and malnutrition in hemodialysis patients.

  6. Flow-mediated lipoprotein retention; Pregnancy-associated plasma protein-A inhibition in atherosclerosis and its release during myocardial ischemia

    DEFF Research Database (Denmark)

    Steffensen, Lasse Bach

    , which states that retention of lipoproteins is the key initiating event of atherosclerosis development. Pregnancy-associated plasma protein-A (PAPP-A) regulates the insulin-like growth factor (IGF) system by proteolytic cleavage of a subset of IGF-binding proteins. Studies in mice have established PAPP...

  7. Pregnancy associated plasma protein A, a potential marker for vulnerable plaque in patients with non-ST-segment elevation acute coronary syndrome

    DEFF Research Database (Denmark)

    Iversen, Kasper; Teisner, Ane S; Teisner, Borge

    2009-01-01

    OBJECTIVES: To describe the presence and time-related pattern of circulating pregnancy associated plasma protein A (PAPP-A) levels in patients with non ST-segment elevation acute coronary syndrome (NSTE-ACS). DESIGN AND METHODS: Consecutively admitted patients (N=573) with clinical signs of NSTE-...

  8. Longitudinal changes in C-reactive protein, proform of eosinophil major basic protein, and pregnancy-associated plasma protein-A during weight changes in obese children

    DEFF Research Database (Denmark)

    Lausten-Thomsen, Ulrik; Gamborg, Michael; Bøjsøe, Christine

    2015-01-01

    BACKGROUND: Childhood obesity is associated with several complications, including cardiovascular comorbidity. Several biomarkers, such as high-sensitive C-reactive protein (hs-CRP), proform of eosinophil major basic protein (Pro-MBP) and pregnancy associated plasma protein-A (PAPP-A), have equally...... been linked to increased cardiovascular susceptibility. This study investigates these biomarkers during weight loss and regain in obese children. MATERIALS AND METHODS: A longitudinal study during a 12-week weight loss program with a 28 months follow-up was conducted. Anthropometrics and plasma......), and 2.70 (girls) were included. Ninety children completed the weight loss program and 68 children entered the follow-up program. Pro-MBP and PAPP-A, but not hs-CRP, exhibited individual-specific levels (tracking) during weight loss and regain. The PAPP-A/Pro-MBP correlation was strong, whereas the hs...

  9. Changes of pregnancy-associated plasma protein-A in patients with acute coronary syndrome

    Institute of Scientific and Technical Information of China (English)

    LIU Jin-lai; ZHANG Hui; XIE Xu-jing; CHEN Lin; ZHAO Chang-lin

    2005-01-01

    @@ The term vulnerable patient has been proposed to define subjects susceptible to an acute coronary syndrome (ACS) or sudden cardiac death based on plaque characteristics, blood abnorma-lities, or myocardial vulnerability.1 It will be important in the future to identify both vulnerable patients and vulnerable plaques. Atherosclerotic arteries obtained at autopsy from patients who died suddenly of cardiac causes indicate that pregnancy-associated plasma protein-A (PAPP-A) was abundantly expressed in plaque cells and in the extracellular matrix of ruptured and eroded unstable plaques, but not in stable plaques.2 Here we examined circulating PAPP-A levels in patients with ACS in order to evaluate its potential use in identifying vulnerable patients.

  10. A prospective study evaluating the performance of first trimester combined screening for trisomy 21 using repeated sampling of the maternal serum markers PAPP-A and free β-hCG

    DEFF Research Database (Denmark)

    Ekelund, Charlotte Kvist; Wright, Dave; Ball, Susan

    2012-01-01

    To prospectively evaluate the performance of first-trimester combined screening for trisomy 21 using the biochemical markers pregnancy-associated plasma protein-A (PAPP-A) and free beta-human chorionic gonadotropin (free β-hCG) obtained before and at the time of the nuchal translucency (NT) scan....

  11. CLINICAL PERFORMANCE CHARACTERISTICS OF ELECSYS® FREE-ΒHCG AND PAPP-A FOR FIRST TRIMESTER TRISOMY 21 RISK ASSESSMENT IN GESTATIONAL WEEKS 8+0 TO 14+0

    DEFF Research Database (Denmark)

    Tørring, Niels; aulesa, C; Eiben, Bernd;

    2014-01-01

    Background Screening for fetal trisomy 21 (T21) in the first trimester includes analysis of the serological markers pregnancy-associated plasma protein A (PAPP-A) and free beta choriogonadotropin (free βhCG). With the launch of these assays on the cobas e and Elecsys platforms, we investigated...

  12. CLINICAL PERFORMANCE CHARACTERISTICS OF ELECSYS® FREE-ΒHCG AND PAPP-A FOR FIRST TRIMESTER TRISOMY 21 RISK ASSESSMENT IN GESTATIONAL WEEKS 8+0 TO 14+0

    DEFF Research Database (Denmark)

    Tørring, Niels; Aulesa, C; Eiben, Bernd;

    2014-01-01

    Background Screening for fetal trisomy 21 (T21) in the first trimester includes analysis of the serological markers pregnancy-associated plasma protein A (PAPP-A) and free beta choriogonadotropin (free βhCG). With the launch of these assays on the cobas e and Elecsys platforms, we investigated...... their clinical and analytical performance. Patients and Methods We conducted a multicenter study in 5397 pregnancies including 108 cases with verified fetal T21 at 8 to 14 weeks of gestation. A technical validation of the Roche Elecsys® free βhCG and PAPP-A assays were performed, including method comparisons...

  13. Genetic relationship between serum pregnancy-associated plasma protein-A gene polymorphism and ischemic cerebrovascular disease in a Northern Han Chinese population

    Institute of Scientific and Technical Information of China (English)

    Haiping Wang; Yan Song; Chen Zhang; Jingjing Zhan; Rui Zhang; Haiji Wang

    2012-01-01

    The present study recruited 193 patients with ischemic cerebrovascular disease from Inpatient and Outpatient Departments at the Affiliated Hospital of Qingdao University Medical College, China from August 2008 to May 2010, as well as 120 healthy volunteers from the Medical Examination Center at the Affiliated Hospital of Qingdao University Medical College, China, who served as controls for this study.Patients and control subjects were from the Han population in northern China.Enzyme- linked immunosorbent assay analysis revealed increased levels of serum pregnancy-associated plasma protein-A (PAPP-A) in ischemic cerebrovascular disease patients compared with healthy controls.In addition, the patients exhibited greater frequency of genotype CC and C alleles in a missense A/C (Tyr/Ser) polymorphism (dbSNP: rs7020782) of exon 14 in the PAPP-A gene.Multiple-factor logistic regression analysis on correction of age, gender, history of smoking, hypertension, diabetes mellitus, hypercholesteremia, and ischemic stroke family history showed that the risk for ischemic cerebrovascular disease in the population without the A allele at the A/C genetic locus in exon 14 of the PAPP-A was 2-folds greater than the population expressing the A allele.These experimental findings suggested that ischemic cerebrovascular disease correlated with the C allele in exon 14 of PAPP-A.In addition, the A allele is likely a protective gene; individuals carrying the A allele were less prone to ischemic cerebrovascular disease compared with individuals without the A allele.

  14. Real-time RT-PCR quantification of pregnancy-associated plasma protein-A mRNA abundance in bovine granulosa and theca cells: effects of hormones in vitro.

    Science.gov (United States)

    Aad, Pauline Y; Voge, Justin L; Santiago, Consuelo A; Malayer, Jerry R; Spicer, Leon J

    2006-11-01

    Ovarian follicular growth and dominance are controlled by a series of hormonal and intraovarian events including a decrease in intrafollicular IGF-binding proteins -2, -4 and -5 levels. Proteolytic enzymes such as pregnancy-associated plasma protein-A (PAPP-A) degrade IGFBPs and increase bioavailability of IGF-I and -II during follicular development. The objective of this study was to determine the effect of IGF-I, IGF-II, insulin (INS), LH, FSH, estradiol (E2), leptin or cortisol on ovarian PAPP-A mRNA levels. Granulosa (GC) from small (SM) (1-5 mm) and large (LG) (8-22 mm) follicles as well as theca cells (TC) from LG follicles were collected from bovine ovaries and cultured for 48 h in medium containing 10% FCS and then treated with various hormones in serum-free medium for an additional 24 h. Cells were treated with various concentrations (3-500 ng/ml) and combinations of IGF-I, IGF-II, FSH, LH, E2, INS, leptin and (or) cortisol for 24 h (Experiments 1-10). PAPP-A mRNA levels were measured using quantitative real-time RT-PCR. In SM-GC and LG-GC, none of the treatments significantly affected (P>0.10) PAPP-A mRNA abundance. In LG-TC, IGF-I, LH or cortisol did not affect (P>0.10) PAPP-A mRNA levels, whereas INS with or without LH decreased (P<0.05) PAPP-A mRNA. E2 alone decreased PAPP-A mRNA levels in LG-TC, and E2 amplified the insulin-induced inhibition of PAPP-A mRNA abundance in LG-TC. We conclude that control of PAPP-A mRNA abundance in granulosa and theca cells differs, and that E2 may be part of an intraovarian negative feedback system which may reduce the bioavailable IGFs in the theca layer during growth and selection of follicles.

  15. First trimester maternal serum pregnancy-associated plasma protein-A is a predictive factor for early preterm delivery in normotensive pregnancies.

    Science.gov (United States)

    Dane, Banu; Dane, Cem; Batmaz, Gonca; Ates, Seda; Dansuk, Ramazan

    2013-06-01

    In this study, we investigated whether the concentrations of pregnancy-associated plasma protein-A (PAPP-A) or free β-hCG (fβhCG) in the first trimester can identify women at increased risk of subsequent preterm delivery in the absence of hypertensive disorders. Preterm and early preterm deliveries are defined as those deliveries before completing 37 and 34 weeks, respectively. A total of 868 women were enrolled into this study. According to the level of the markers, the patients were evaluated in three groups: 1 - maternal serum level ≤ 5 th percentile, 2 - between 5th and 95th percentiles, 3 - ≥ 95 th percentile. In the group of patients with a PAPP-A level ≤ 5 th percentile [≤ 0.35 multiples of the median (MoM)], mean gestational age (GA) at delivery, mean birth weight and the number of the cases with early preterm delivery were significantly lower than the others. Mean level of PAPP-A was significantly lower in cases with early preterm than term deliveries (0.58 ± 0.32 versus 1.09 ± 0.69; p = 0.01). Maternal serum level of fβhCG did not show significant difference between these groups (0.84 ± 0.45 versus 1.17 ± 0.77; p = 0.15). Low levels of maternal serum PAPP-A (≤ 0.35 MoM) (Odds ratio = 7; 95% confidence interval 1.8-27.7; p = 0.0048) significantly predicted early preterm delivery in normotensive pregnancies. Women with low levels of PAPP-A at first trimester have a higher risk of early preterm delivery even in the absence of hypertensive disorders.

  16. Skp2B overexpression alters a prohibitin-p53 axis and the transcription of PAPP-A, the protease of insulin-like growth factor binding protein 4.

    Directory of Open Access Journals (Sweden)

    Harish Chander

    Full Text Available BACKGROUND: We previously reported that the degradation of prohibitin by the SCF(Skp2B ubiquitin ligase results in a defect in the activity of p53. We also reported that MMTV-Skp2B transgenic mice develop mammary gland tumors that are characterized by an increased proteolytic cleavage of the insulin-like growth factor binding protein 4 (IGFBP-4, an inhibitor of IGF signaling. However, whether a link exists between a defect in p53 activity and proteolysis of IGFBP-4 was not established. METHODS AND RESULTS: We analyzed the levels of pregnancy-associated plasma protein A (PAPP-A, the protease of IGFBP-4, in MMTV-Skp2B transgenic mice and found that PAPP-A levels are elevated. Further, we found a p53 binding site in intron 1 of the PAPP-A gene and that both wild type and mutant p53 bind to this site. However, binding of wild type p53 results in the transcriptional repression of PAPP-A, while binding of mutant p53 results in the transcriptional activation of PAPP-A. Since MMTV-Skp2B mice express wild type p53 and yet show elevated levels of PAPP-A, at first, these observations appeared contradictory. However, further analysis revealed that the defect in p53 activity in Skp2B overexpressing cells does not only abolish the activity of wild type of p53 but actually mimics that of mutant p53. Our results suggest that in absence of prohibitin, the half-life of p53 is increased and like mutant p53, the conformation of p53 is denatured. CONCLUSIONS: These observations revealed a novel function of prohibitin as a chaperone of p53. Further, they suggest that binding of denatured p53 in intron 1 causes an enhancer effect and increases the transcription of PAPP-A. Therefore, these findings indicate that the defect in p53 function and the increased proteolysis of IGFBP-4, we had observed, represent two components of the same pathway, which contributes to the oncogenic function of Skp2B.

  17. Second-trimester levels of pregnancy-associated plasma protein-A and free beta-hCG in pregnancies with trisomy 13.

    Science.gov (United States)

    Spencer, K; Crossley, J A; Aitken, D A; Nicolaides, K H

    2005-05-01

    To examine the levels of free beta-human chorionic gonadotrophin (free beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A) in second-trimester maternal serum from pregnancies affected by trisomy 13 and compare these with the known reduced levels of these markers in first-trimester cases in an attempt to better understand the pathophysiology of changes in marker levels in chromosomally abnormal pregnancies between the first and second trimester. Using the Kryptor immunoassay system, we measured free beta-hCG and PAPP-A in 32 singleton pregnancies affected by trisomy 13 between 14 and 20 weeks of gestation. Using medians established in a previous study, these results were compared against 450 normal singleton pregnancies over the same gestational range. The data were combined with data from 82 cases of trisomy 13 previously examined in the first trimester (11-13 weeks) and an analysis of analyte trend was performed. The median free beta-hCG in multiples of the appropriate gestational median (MoM) in the second-trimester samples was not significantly different from the controls (1.15 (95% CI 0.827-1.651) vs 1.00). The median PAPP-A MoM in the second-trimester samples was significantly lower (phCG MoM of 0.58 (95% CI 0.454-0.668) and a median PAPP-A MoM of 0.26 (95% CI 0.218-0.320). For PAPP-A, there was no significant change in median across the gestational period of 11 to 20 weeks, whilst for free beta-hCG, there was a significant increase with gestation (r=0.458, ptrisomy 13 pregnancies in the second trimester, this isolated lower marker value is unlikely to be of value in screening for trisomy 13 in the second trimester. The aetiology of reduced levels of PAPP-A in cases with trisomy 13 may be similar to that in cases with trisomy 18, but different from that in cases with trisomy 21 since the temporal pattern in trisomies 13 and 18 are different from that in trisomy 21. Copyright (c) 2005 John Wiley & Sons, Ltd.

  18. First-trimester screening for trisomy 21 by free beta-human chorionic gonadotropin and pregnancy-associated plasma protein-A: impact of maternal and pregnancy characteristics.

    Science.gov (United States)

    Kagan, K O; Wright, D; Spencer, K; Molina, F S; Nicolaides, K H

    2008-05-01

    To use multiple regression analysis to define the contribution of maternal variables that influence the measured concentration of free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A), and the interaction between these covariates, in first-trimester biochemical screening for trisomy 21. This was a multicenter study of prospective screening for trisomy 21 by a combination of fetal nuchal translucency thickness, and maternal serum free beta-hCG and PAPP-A at 11 + 0 to 13 + 6 weeks of gestation. In the pregnancies subsequently found to have trisomy 21 and in those with no obvious chromosomal abnormality, we used multiple regression analysis to account for pregnancy characteristics that influence the measured concentrations of free beta-hCG and PAPP-A. We fitted Gaussian distributions to the distribution of log multiples of the median (MoM) values in trisomy 21 and in unaffected pregnancies. There were 491 cases of trisomy 21 and 96 803 chromosomally normal pregnancies. Compared with values in Caucasian women, those who were parous, non-smokers and those who conceived spontaneously, PAPP-A was 57% higher in women of Afro-Caribbean origin, 3% higher in South Asians, 9% higher in East Asians, 2% higher in nulliparous women, 17% lower in smokers and 10% lower in those conceiving by in-vitro fertilization (IVF). Free beta-hCG was 12% higher in women of Afro-Caribbean origin, 9% lower in South Asians, 8% higher in East Asians, 2% higher in nulliparous women, 4% lower in smokers and 9% higher in those conceiving by IVF. In screening for trisomy 21 by maternal age and serum free beta-hCG and PAPP-A the estimated detection rate was 65% for a false-positive rate of 5%. In first-trimester biochemical screening for trisomy 21 it is essential to adjust the measured values of free beta-hCG and PAPP-A for maternal and pregnancy characteristics. Copyright (c) 2008 ISUOG

  19. Analysis of correlation between maternal serum PAPP-A and gestational diabetes mellitus%孕妇血清PAPP-A与妊娠期糖尿病相关性分析

    Institute of Scientific and Technical Information of China (English)

    贺艳; 谷美丽; 刘敏; 蔡敏

    2015-01-01

    Objective To observe the relationship between maternal serum pregnancy-associated plasma protein-A (PAPP-A) and gestational diabetes mellitus.Methods There were 246 patients with gestational Down's syndrome. Those with gestational and postnatal normal fetal structures and no pregnancy complications were set as control group, and they were comparatively analyzed with patients of serum PAPP-A complicated with gestational diabetes mellitus for showing their differences in serum PAPP-A levels.Results Research showed that there were 17 cases complicated with gestational diabetes mellitus among the 246 chosen gestational Down's syndrome cases. Low level of PAPP-A was closely correlated with spontaneous abortion, pregnancy-induced hypertension, and gestational diabetes mellitus, and it could be taken as an important referring index for gestational diabetes mellitus.Conclusion The significant correlation between maternal serum PAPP-A level and gestational diabetes mellitus in early pregnancy can be regarded as the important index for clinical diagnosis.%目的:观察孕妇血清妊娠相关蛋白-A(PAPP-A)与妊娠期糖尿病之间的关系。方法246例孕期唐氏综合征患者,其中将孕期胎儿结构正常、未发生妊娠并发症及出生后新生儿正常的病例设为对照组,同时与并发妊娠期糖尿病的孕妇进行对比分析,比较其血清PAPP-A水平差异。结果调查结果显示,在选取的246例孕期唐氏综合征患者筛查中并发妊娠期糖尿病17例,低PAPP-A水平与自然流产、妊娠期高血压综合征、妊娠期糖尿病等存在显著相关性,低PAPP-A可作为妊娠期糖尿病的重要参考指标。结论早孕期母血清PAPP-A值与妊娠期糖尿病具有显著的相关性,可作为临床诊断的重要指标。

  20. Longer time-to-pregnancy in spontaneously conceived pregnancies is associated with lower PAPP-A and free β-hCG in first trimester screening for Down syndrome.

    Science.gov (United States)

    Kirkegaard, I; Uldbjerg, N; Tabor, A; Henriksen, T B

    2014-03-01

    The aim of this study was to investigate whether subfertility, measured as longer time-to-pregnancy (TTP) in spontaneously conceived pregnancies, affects the first trimester levels of pregnancy-associated plasma protein-A (PAPP-A) and free beta-human chorionic gonadotrophin (β-hCG) and hence the risk estimates in Down syndrome screening. The study included a cohort of 10 469 singleton pregnant women who underwent first trimester combined screening and responded to a questionnaire regarding TTP. PAPP-A and free β-hCG levels were measured between gestational week 8 + 0 and 13 + 6 and were related to TTP. The median PAPP-A and free β-hCG MoMs were significantly lower in women with a TTP ≥24 months compared with the reference group with a TTP hCG: 1.04 vs 1.12 MoM, p = 0.03). This led to an increased odds for trisomy 21 risk ≥1 : 300 for TTP ≥24 months compared with TTP hCG. © 2013 John Wiley & Sons, Ltd.

  1. Pregnancy-associated plasma protein A in a large cohort of Type 1 diabetic patients with and without diabetic nephropathy-a prospective follow--up study

    DEFF Research Database (Denmark)

    Astrup, A S; Tarnow, L; Christiansen, M

    2007-01-01

    with diabetic nephropathy, plasma PAPP-A was elevated 3.6 (0.4-51.1) mIU/l [median (range)] vs. 2.1 (0.4-46.6) mIU/l in normoalbuminuric patients, P ... (35%) died, compared with 60 of 338 patients (18%) below the threshold; log rank test P = 0.007. PAPP-A significantly predicted mortality after adjustment for presence of nephropathy; hazard ratio for dying when PAPP-A was above the threshold 2.1 (95% CI 1.13-3.9); P = 0.019. After adjusting...... for traditional risk factors, the results were attenuated. When only patients with nephropathy were analysed, PAPP-A was significantly predictive of all-cause mortality [P = 0.008; 2.43 (1.26-4.67)] in unadjusted analysis. After adjustment, the predictive value of PAPP-A for all-cause mortality was attenuated (P...

  2. Screening for trisomy 13 by fetal nuchal translucency and maternal serum free beta-hCG and PAPP-A at 10-14 weeks of gestation.

    Science.gov (United States)

    Spencer, K; Ong, C; Skentou, H; Liao, A W; H Nicolaides, K

    2000-05-01

    In 42 cases of trisomy 13 at 10-14 weeks of gestation, compared with 947 controls, the median multiple of the median (MoM) of maternal serum free beta-human chorionic gonadotrophin (beta-hCG) and pregnancy associated plasma protein A (PAPP-A) was significantly decreased (0.506 MoM and 0.248 MoM respectively), whilst fetal nuchal translucency was increased (2.872 MoM). In 38% and 71% of cases of trisomy 13 maternal serum free beta-hCG and PAPP-A was below the 5th centile of the appropriate normal range for gestation and in 62% of cases the nuchal translucency was above the 95th centile. When combined together in a multivariate algorithm with maternal age, 90% of cases of trisomy 13 could be detected at a 0.5% false positive rate or 84% at a 0.1% false positive rate. We conclude that specific trisomy 13 risks should be part of developing risk algorithms combining maternal serum biochemistry and nuchal translucency for use in first trimester screening alongside those for trisomy 21 and trisomy 18. Copyright 2000 John Wiley & Sons, Ltd.

  3. Screening for trisomy 21 in twin pregnancies in the first trimester: does chorionicity impact on maternal serum free beta-hCG or PAPP-A levels?

    Science.gov (United States)

    Spencer, K

    2001-09-01

    In a study of 180 twin pregnancies I have examined the distribution of maternal serum free beta-human chorionic gonadotrophin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A), in addition to fetal nuchal translucency thickness (NT), in twins classified as monochorionic or dichorionic, based on ultrasound appearance at 10-14 weeks of gestation. In 45 monochorionic and 135 dichorionic twin pregnancies the median MoM free beta-hCG was not significantly different (1.00 vs 1.01), whilst that for PAPP-A was lower (0.89 vs 1.01) but again with no statistical significance. Previous reports of an increased fetal NT in monochorionic twins pregnancies could not be confirmed (1.03 vs 1.00). It is concluded that the existing pseudo risk twin correction algorithm is appropriate for both monochorionic and dichorionic twins in providing accurate first trimester risks for trisomy 21. Copyright 2001 John Wiley & Sons, Ltd.

  4. Screening for trisomy 18 by fetal nuchal translucency and maternal serum free beta-hCG and PAPP-A at 10-14 weeks of gestation.

    Science.gov (United States)

    Tul, N; Spencer, K; Noble, P; Chan, C; Nicolaides, K

    1999-11-01

    In a study of 50 cases of trisomy 18 compared with 947 controls we have found the median multiple of the median (MoM) of maternal serum free beta human chorionic gonadotrophin to be significantly decreased (0.281 MoM) in samples collected between the 10th and 14th week of gestation. Similarly, maternal serum pregnancy associated plasma protein A (PAPP-A) levels are also decreased (0.177 MoM), whilst the median nuchal translucency is significantly higher (3.272 MoM). Free beta-hCG MoM was less than the 5th centile of normal in 64 per cent of cases of trisomy 18 and for PAPP-A was less than the 5th centile in 78 per cent of cases. Also, in 78 per cent of cases the nuchal translucency was above the 95th centile. When combined together in a multivariate algorithm with maternal age, we predict that 89 per cent of cases of trisomy 18 could be detected at a 1 per cent false-positive rate. We conclude that specific trisomy 18 risks should be part of developing risk algorithms combining maternal serum biochemistry and nuchal translucency for use in first trimester screening alongside those for trisomy 21.

  5. First Trimester Maternal Serum Screening Using Biochemical Markers PAPP-A and Free β-hCG for Down Syndrome, Patau Syndrome and Edward Syndrome.

    Science.gov (United States)

    Shiefa, S; Amargandhi, M; Bhupendra, J; Moulali, S; Kristine, T

    2013-01-01

    The first trimester screening programme offers a noninvasive option for the early detection of aneuploidy pregnancies. This screening is done by a combination of two biochemical markers i.e. serum free β-human chorionic gonadotrophin (free β-hCG) and pregnancy associated plasma protein A (PAPP-A), maternal age and fetal nuchal translucency (NT) thickness at 11 + 0-13 + 6 weeks of gestation. A beneficial consequence of screening is the early diagnosis or trisomies 21, 18 and 13. At 11 + 0-13 + 6 weeks, the relative prevalence of trisomies 18 and 13 to trisomy 21 are found to be one to three and one to seven, respectively. All three trisomies are associated with increased maternal age, increased fetal NT and decreased PAPP-A, but in trisomy 21 serum free β-hCG is increased whereas in trisomies 18 and 13 free β-hCG is decreased.

  6. Screening for trisomy 21 by fetal tricuspid regurgitation, nuchal translucency and maternal serum free beta-hCG and PAPP-A at 11 + 0 to 13 + 6 weeks.

    Science.gov (United States)

    Falcon, O; Auer, M; Gerovassili, A; Spencer, K; Nicolaides, K H

    2006-02-01

    To examine whether in pregnancies with fetal trisomy 21 the level of maternal serum free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 11 + 0 to 13 + 6 weeks' gestation is independent of the presence or absence of tricuspid regurgitation and to estimate the performance of a screening test that combines tricuspid regurgitation with fetal nuchal translucency (NT) thickness and serum free beta-hCG and PAPP-A. The study population comprised 77 trisomy 21 and 232 chromosomally normal fetuses from singleton pregnancies at 11 + 0 to 13 + 6 weeks of gestation. In all cases the fetal karyotype was determined by chorionic villus sampling (CVS), which was carried out at the request of the parents after first-trimester screening for trisomy 21 by fetal NT and maternal serum free beta-hCG and PAPP-A. Immediately before chorionic villus sampling, fetal echocardiography was performed and the presence or absence of tricuspid regurgitation was determined by pulsed wave Doppler ultrasonography. The distribution of fetal NT, maternal serum free beta-hCG and PAPP-A in trisomy 21 fetuses with absent and present tricuspid regurgitation was examined. We examined two screening strategies: first, integrated first-trimester screening in all patients and second, first-stage screening of all patients using fetal NT and maternal serum free beta-hCG and PAPP-A followed by second-stage assessment of tricuspid regurgitation only in those with an intermediate risk of 1 in 101 to 1 in 1000 after the first stage. Tricuspid regurgitation was observed in 57 (74.0%) of the trisomy 21 fetuses and in 16 (6.9%) of the chromosomally normal fetuses. There were no significant differences in median maternal age, median gestational age, free beta-hCG multiples of the median (MoM) and PAPP-A MoM in trisomy 21 fetuses with and without tricuspid regurgitation. The modeled detection rates of trisomy 21 for fixed false positive rates of 1%, 2% and 5% in screening

  7. Levels of pregnancy associated plasma protein A and interleukin 6 and their clinical significance in prehypertension patients with impaired glucose tolerance%高血压前期合并糖耐量减低患者妊娠相关血浆蛋白A与白介素6水平变化及其临床意义的观察

    Institute of Scientific and Technical Information of China (English)

    江文艳; 王希柱; 宋巧凤; 唐蕊; 肖四海; 朱艳辉

    2013-01-01

    Objective To study the levels of pregnancy associated plasma protein A (PAPP-A) and interleukin 6 (IL-6) in patients with prehypertension (PH) and IGT.Methods We recruited 100 prehypertension(PH) patients,among them 50 with normal glucose tolerance (NGT) and 50 with IGT.The levels of pregnancy associated plasma protein A and interleukin 6 were determined by ELISA.Results The levels of PAPP-A and IL-6 in patients with PH and IGT were higher than patients with PH and NGT [PAPP-A (12.43±3.65) vs (9.50±3.39) mU/L,IL-6 (101.64±19.13) vs (87.56±17.32)ng/L,all P<0.05].Multivariate logistic regression analysis showed PAPP-A,IL-6,BMI and systolic blood pressure were predisposing risk factors for perhypertensive patients with IGT.Conclusion PAPP-A and IL-6 are enhanced in prehypertension with IGT.%目的 观察妊娠相关血浆蛋白A(PAPP-A)和白介素6(IL-6)在高血压前期(PH)合并IGT患者中的水平变化,并探讨其之间的关系. 方法 入选PH患者100例,其中合并IGT(PH +IGT)者50例,糖耐量正常(PH+NGT)者50例.采用ELISA法测血浆中PAPP-A、IL-6含量. 结果 PH+IGT组PAPP-A和IL-6水平高于PH+ NGT组[PAPP-A(12.43士3.65)vs(9.50士3.39)mU/L,IL-6(101.64±19.13)vs(87.56士17.32) ng/L,P<0.05].多因素Logistic回归分析显示,PAPP-A和IL-6是IGT合并PH的部分危险因素. 结论 PH合并IGT患者PAPP-A和IL-6水平增高.

  8. [The value of maternal first and second trimester serum data of β-hCG, PAPP-A, AFP and uE3 in the prediction of preeclampsia].

    Science.gov (United States)

    Gu, Wei; Lin, Jing; Hou, Yanyan

    2015-02-01

    To discover the value of combined maternal first and second-trimester serum β-hCG, pregnancy associated plasma protein A (PAPP-A), alpha-fetoprotein(AFP)and unconjugated estriol (uE3) in the prediction of preeclampsia. A total of 1 805 pregnant women who had antenatal care at International Peace Maternal and Child Health Hospital Affiliated to Shanghai Jiaotong University between April 2012 and June 2013 were selected prospectively by random method. According to the outcome, they were defined as the control group and the preeclampsia group (including mild and severe cases). PAPP-A and β-hCG level were measured at 10-14 gestational weeks. AFP, β-hCG and uE3 were measured at 15-20 gestational weeks. The relevance between the serological indicators and outcomes was analyzed. The value of the indicators was judged by receiver operating characteristic (ROC) and Youden index, and the relevant predictive boundary values were identified. (1) Among the 1 805 cases, 1 739 women did not have hypertension(the control group), while 66 women had preeclampsia (the preeclampsia group). The incidence of preeclampsia was 3.66% (66/1 805), including 43 mild cases and 23 severe cases. (2) At 10-14 gestational weeks, the mean value of PAPP-A in the control group was (3 972 ± 2 311) mU/L, while in the preeclampsia group it was (2 837 ± 1 849)mU/L. The difference between the two groups had statistical significance (P hCG of the control group was 55(37∼83) U/L, while in the preeclampsia group it was (57 ± 35)U/L. There was no statistical significance (P > 0.05). PAPP-A, β-hCG and AFP of mild preeclampsia cases were (3 249 ± 1 877) mU/L, (61 ± 38) U/L and (35 ± 11) µg/L respectively, and in severe cases they were(1 758 ± 1 297)mU/L, (47 ± 23)U/L and (47 ± 22)µg/L, respectively. There was statistically significant difference in PAPP-A (P hCG, AFP and uE3 in the preeclampsia group were (47 909 ± 31 396 )U/L, (38 ± 15)µg/L and (0.98 ± 0.31)µg/L respectively, and in the

  9. Development of a recombinant antibody towards PAPP-A for immunohistochemical use in multiple animal species

    DEFF Research Database (Denmark)

    Mikkelsen, Jakob H; Steffensen, Lasse B; Oxvig, Claus

    2014-01-01

    normal physiology and under different pathological conditions. However, antibodies for the detection of PAPP-A in non-human tissues have been lacking, although needed for use with several animal models which are currently being developed. To develop a monoclonal antibody suitable...... for the immunohistochemical detection of PAPP-A, we therefore selected a phage-derived scFv antibody, PAC1, specifically recognizing an epitope of PAPP-A, which is highly conserved between multiple animal species. We first converted this antibody into bivalent IgG, and verified its ability to recognize PAPP-A in sections...

  10. Prospective study evaluating performance of first-trimester combined screening for trisomy 21 using repeat sampling of maternal serum markers PAPP-A and free β-hCG.

    Science.gov (United States)

    Ekelund, C; Wright, D; Ball, S; Kirkegaard, I; Nørgaard, P; Sørensen, S; Friis-Hansen, L; Jørgensen, F S; Tørring, N; Bech, B H; Petersen, O B; Tabor, A

    2012-09-01

    To prospectively evaluate the performance of first-trimester combined screening for trisomy 21 using the biochemical markers pregnancy-associated plasma protein-A (PAPP-A) and free beta-human chorionic gonadotropin (free β-hCG) obtained before and at the time of the nuchal translucency (NT) scan. Three fetal medicine departments in Denmark participated in the study. Screening for trisomy 21 was set up as a two-step approach with blood sampling performed before the NT scan (early sample) and again at the time of the NT scan (late sample). PAPP-A and free β-hCG were measured on both the early and late samples. Age-standardized detection and false-positive rates for different screening protocols were calculated. We collected two blood samples in 27 pregnancies affected by trisomy 21 and in 3891 control pregnancies. The early samples were taken between gestational ages 8 + 0 and 13 + 6 weeks, and the late samples between 11 + 3 and 14 + 6 weeks. The median interval between the samples was 17 (range, 1-40) days. We found a significantly better estimated screening performance when using early sampling vs late sampling (P trisomy 21, use of early sampling with measurement of PAPP-A and free β-hCG before the time of the NT scan can optimize screening performance. Using maternal serum markers obtained both before and at the time of the NT scan has the potential to further improve performance, but larger studies are needed to confirm this potential. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.

  11. Integrated ultrasound and biochemical screening for trisomy 21 using fetal nuchal translucency, absent fetal nasal bone, free beta-hCG and PAPP-A at 11 to 14 weeks.

    Science.gov (United States)

    Cicero, Simona; Bindra, Renu; Rembouskos, Georgios; Spencer, Kevin; Nicolaides, Kypros H

    2003-04-01

    Screening for trisomy 21 by a combination of maternal age, fetal nuchal translucency (NT) thickness and maternal serum free beta-hCG and pregnancy-associated plasma protein-A (PAPP-A) at 11 to 14 weeks of gestation is associated with a detection rate of 90% for a false-positive rate of 5%. Recent evidence suggests that in about 70% of fetuses with trisomy 21, the nasal bone is not visible at the 11th- to 14th-week scan (Cicero et al., 2001). The aim of this study was to examine whether fetal NT thickness and the level of maternal serum biochemical markers is independent of the presence or absence of the nasal bone, and to estimate the performance of a screening test that integrates the two sonographic and the two biochemical markers. This was a retrospective case-control study comprising 100 trisomy 21 and 400 chromosomally normal singleton pregnancies at 11 to 14 weeks of gestation. Ultrasound examination was carried out for measurement of fetal NT and assessment of the presence or absence of the fetal nasal bone. Maternal serum free beta-hCG and PAPP-A were measured using the Kryptor rapid random-access immunoassay analyser (Brahms Diagnostica GmbH, Berlin). The distribution of fetal NT, maternal serum free beta-hCG and PAPP-A in trisomy 21 fetuses with absent and present nasal bone was examined. The nasal bone was absent in 69 and present in 31 of the trisomy 21 fetuses. There were no significant differences in median maternal age, median gestational age, NT delta, free beta-hCG MoM and PAPP-A MoM in trisomy 21 fetuses with and without a visible nasal bone. For a false-positive rate of 5%, it was estimated that screening with the four markers in combination with maternal age would be associated with a detection rate of 97%. For a false-positive rate of 0.5%, the detection rate was 90.5%. An integrated sonographic and biochemical test at 11 to 14 weeks can potentially identify about 90% of trisomy 21 fetuses for a false-positive rate of 0.5%. Copyright 2003 John

  12. Impact of bias in serum free beta-human chorionic gonadotropin and pregnancy-associated plasma protein-A multiples of the median levels on first-trimester screening for trisomy 21.

    Science.gov (United States)

    Wright, D; Abele, H; Baker, A; Kagan, K O

    2011-09-01

    To examine the effect of bias in median multiples of the median (MoM) levels of pregnancy-associated plasma protein-A (PAPP-A) and free beta-human chorionic gonadotropin (β-hCG) on first-trimester combined screening for trisomy 21. The effects of deviations in the MoM levels of free β-hCG and PAPP-A were investigated by simulating nuchal translucency (NT) at 12 weeks and MoM values for PAPP-A and free β-hCG for 500 000 euploid and 500 000 trisomy 21 pregnancies at 9 and at 12 weeks of gestation. Likelihoods were calculated using the mixture model for NT and the standard Gaussian model for log MoM PAPP-A and free β-hCG values. Deviations in MoM marker levels were simulated by applying percentage changes of 5% to 20% to MoM values. Detection and false-positive rates were calculated with and without adjustments of the maternal serum marker levels by taking the proportion of euploid and aneuploid cases above given thresholds for each maternal age and then taking a weighted average with respect to the maternal age distribution. With median MoM levels on target, the modeled detection and false-positive rates in combined screening for trisomy 21 at 12 weeks of gestation with a fixed risk cut-off of 1 in 100 were 85% and 2.5%, respectively. For median MoM levels of free β-hCG and PAPP-A between 0.8 and 1.2 MoM, detection rates ranged from 77% to 91%, with corresponding false-positive rates ranging from 1.0% to 6.1%. In first-trimester screening for trisomy 21, biases in the serum marker MoM levels of 10% can increase false-positive rates by over 50%, whilst biases of 20% can more than double false-positive rates. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.

  13. Screening for trisomies 21, 18 and 13 by maternal age, fetal nuchal translucency, fetal heart rate, free beta-hCG and pregnancy-associated plasma protein-A.

    Science.gov (United States)

    Kagan, Karl O; Wright, Dave; Valencia, Catalina; Maiz, Nerea; Nicolaides, Kypros H

    2008-09-01

    A beneficial consequence of screening for trisomy 21 is the early diagnosis of trisomies 18 and 13. Our objective was to examine the performance of first-trimester screening for trisomies 21, 18 and 13 by maternal age, fetal nuchal translucency (NT) thickness, fetal heart rate (FHR) and maternal serum-free beta-hCG and pregnancy-associated plasma protein-A (PAPP-A). Prospective screening for trisomy 21 by maternal age, fetal NT, free beta-hCG and PAPP-A at 11(+0)-13(+6) weeks in singleton pregnancies, including 56 376 normal cases, 395 with trisomy 21, 122 with trisomy 18 and 61 with trisomy 13. Risk algorithms were developed for the calculation of patient-specific risks for each of the three trisomies based on maternal age, NT, FHR, free beta-hCG and PAPP-A. Detection (DR) and false positive rates (FPR) were calculated and adjusted according to the maternal age distribution of pregnancies in England and Wales in 2000-2002. The DR and FPR were 90% and 3%, respectively, for trisomy 21, 91% and 0.2% for trisomy 18 and 87% and 0.2% for trisomy 13. When screen positivity was defined by an FPR of 3% on the risk for trisomy 21 in conjunction with an FPR of 0.2% on the maximum of the risks for trisomies 13 and 18, the overall FPR was 3.1% and the DRs of trisomies 21, 18 and 13 were 91%, 97% and 94%, respectively. As a side effect of first-trimester screening for trisomy 21, approximately 95% of trisomy 13 and 18 fetuses can be detected with an 0.1% increase in the FPR.

  14. First-trimester combined screening for trisomy 21 with different combinations of placental growth factor, free β-human chorionic gonadotropin and pregnancy-associated plasma protein-A.

    Science.gov (United States)

    Kagan, K O; Hoopmann, M; Abele, H; Alkier, R; Lüthgens, K

    2012-11-01

    To examine placental growth factor (PlGF) in euploid and trisomy 21 pregnancies at 11-13 weeks' gestation and to model the impact on first-trimester combined screening. PlGF was measured in 509 (409 euploid and 100 trisomic) fetal serum samples derived from prospective first-trimester combined screening for trisomy 21 at 11-13 weeks' gestation. The serum samples were stored at -80°C, following the measurement of free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein-A (PAPP-A) levels, for median time spans of 0.9 and 4.1 years in the euploid and trisomy 21 pregnancies, respectively. The effect of additional PlGF measurement at the time of combined screening was investigated by simulating fetal nuchal translucency (NT) measurements and multiples of the median (MoM) values for PAPP-A, free β-hCG and PlGF for 20,000 euploid and 20,000 trisomy 21 pregnancies. Patient-specific combined risks were calculated based on maternal age and fetal NT in addition to free β-hCG, PAPP-A and PlGF, PAPP-A and PlGF or free β-hCG and PlGF, and detection and false-positive rates were calculated. Median PlGF-MoM was 1.0 (95% confidence interval (CI), 0.96-1.04) in euploid fetuses and significantly lower, at 0.73 (95% CI, 0.70-0.76), in trisomy-21 fetuses (P hCG provided detection rates of 82% and 79%, with false-positive rates of 2.7% and 3.0%, respectively. In pregnancies with trisomy 21 PlGF is reduced. The impact on the overall screening performance for trisomy 21 is low and does not justify the measurement of PlGF solely for trisomy 21 screening. However, as PlGF is measured with the aim of assessing the risk for pre-eclampsia, further improvement in screening for trisomy 21 can be considered as an added benefit. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.

  15. The Immunosignature of Mother/Fetus Couples in Gestational Diabetes Mellitus: Role of HLA-G 14 bp ins/del and PAPP-A A/C Polymorphisms in the Uterine Inflammatory Milieu

    Directory of Open Access Journals (Sweden)

    Miryam Martinetti

    2017-01-01

    Full Text Available We enrolled 151 healthy mother/newborn couples and 26 with gestational diabetes mellitus (GDM. HLA-G and PAPP-A plasma levels were measured by ELISA at first and second trimesters, at delivery, and in cord blood. HLA-G 14 bp ins/del and PAPP-A A/C polymorphisms were genotyped. HLA-G del/del and PAPP-A C/C genotypes were more frequent among GDM mothers than controls. We observed a genetic epistasis between the two polymorphisms: the HLA-G del/del and PAPP-A C/C combination was carried by 8% of GDM mothers and 1.3% of controls (OR = 9.5, 95% CI = 0.8–109, p=0.07. GDM mothers showed increased sHLA-G levels compared to controls (p=0.004, and those carrying the HLA-G del/del genotype produced more sHLA-G at the second trimester and at delivery (p=0.014. A genetic pressure by fetal genotype on maternal sHLA-G production was observed in GDM mothers with heterozygous HLA-G del/ins newborns (p=0.02. Babies born to GDM mothers showed higher sHLA-G concentrations compared to those born to healthy mothers, and those carrying HLA-G del/del showed the highest sHLA-G levels (p=0.013. PAPP-A amounts significantly increased along pregnancy (p<0.001, but the median levels at the first and second trimesters were significantly lower in GDM (p=0.03. Our findings first suggest an involvement of HLA-G and PAPP-A gene-protein interaction in GDM and highlight a possible contribution of the fetus in balancing maternal inflammation.

  16. Preterm delivery in women with low PAPP-A at first trimester screening

    Directory of Open Access Journals (Sweden)

    Razieh Mohamad Jafari

    2014-10-01

    Conclusion: We found high frequency of preterm delivery in pregnant women with low PAPP-A level at the first trimester screening. Hence, this group of patients needs special and early preventive management. Furthermore, we suggest that future researches to be conducted with larger sample size and also cervix length measurement to be included.

  17. Pregnancy-associated plasma protein A in non-cardiac conditions

    DEFF Research Database (Denmark)

    Iversen, K.K.; Teisner, A.S.; Teisner, B.;

    2008-01-01

    OBJECTIVE: PAPP-A is a promising new marker in coronary heart disease. It is important to investigate its specificity in order to establish its clinical utility as a marker of coronary heart disease. DESIGN AND METHODS: PAPP-A was measured within 24 h following hospital admission in 1448...

  18. Pregnancy-associated plasma protein A in non-cardiac conditions

    DEFF Research Database (Denmark)

    Iversen, Kasper Karmark; Søgaard Teisner, Ane; Teisner, Børge

    2008-01-01

    OBJECTIVE: PAPP-A is a promising new marker in coronary heart disease. It is important to investigate its specificity in order to establish its clinical utility as a marker of coronary heart disease. DESIGN AND METHODS: PAPP-A was measured within 24 h following hospital admission in 1448 consecut...

  19. 阿托伐他汀对高血压前期合并高脂血症患者血压及妊娠相关血浆蛋白A的影响%Impact of Atorvastatin Therapy on Blood Pressure and Pregnancy Associated Plasma Protein A in Patients with Prehypertension and Hyperlipidemia

    Institute of Scientific and Technical Information of China (English)

    江文艳; 宋巧凤; 王希柱; 郭永辉

    2011-01-01

    Objective To observe the therapeutic effects of atorvastatin on blood pressure and pregnancy associated plasma protein A ( PAPP - A ) in patients with prehypertension and hyperlipidemia. Methods Eighty patients with prehyperten-sion and hyperlipidemia were enrolled in the study and randomly divided into the treatment group and the control group. The control group was treated with placebo and the treatment group was treated with atorvastatin for 12 weeks. Blood pressure, pregnancy associated plasma protein A and lipid levels were checked after treatment and compared between the two groups. Results After 12 weeks of treatment, blood pressure, total cholesterol level ( TC ), triglyceride (TG), low density lipoprotein cholesterol level ( LDL - C ) and pregnancy associated plasma protein A ( PAPP - A ) were significantly decreased ( P 0. 05 ). Conclusion Intervention treatment with atorvastatin is one of the effective measures that decrease blood pressure and pregnancy associated plasma protein A in patients with prehypertension.%目的 探讨阿托伐他汀对高血压前期合并高脂血症患者血压及妊娠相关血浆蛋白A(PAPP-A)的影响.方法 将体检发现的80例高血压前期合并高脂血症患者随机分为治疗组和对照组,治疗组进行12周阿托伐他汀药物干预性治疗;对照组给予安慰剂治疗.观察两组患者治疗前后血压、血脂及PAPP-A水平的变化.结果 治疗12周后,治疗组血压、血清总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)及PAPP-A水平较治疗前及对照组均有明显下降(P<0.05),血清高密度脂蛋白胆固醇(HDL-C)较治疗前及对照组明显上升(P<0.05),而对照组治疗前后上述指标均无明显变化(P>0.05).结论 阿托伐他汀在有效降脂的同时,可以降低高血压前期患者的血压及PAPP-A水平.

  20. Screening for trisomy 18 by maternal age, fetal nuchal translucency, free beta-human chorionic gonadotropin and pregnancy-associated plasma protein-A.

    Science.gov (United States)

    Kagan, K O; Wright, D; Maiz, N; Pandeva, I; Nicolaides, K H

    2008-09-01

    To derive a model and examine the performance of first-trimester screening for trisomy 18 by maternal age, fetal nuchal translucency (NT) thickness, and maternal serum free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A). Prospective combined screening for trisomy 21 was performed at 11 + 0 to 13 + 6 weeks in 56 893 singleton pregnancies, including 56 376 cases of euploid fetuses, 395 with trisomy 21 and 122 with trisomy 18. The measured free beta-hCG and PAPP-A were converted into a multiple of the median (MoM) and then into likelihood ratios (LR). Similarly, the measured NT was transformed into LRs using the mixture model of NT distributions. In each case the LRs for NT and the biochemical markers were multiplied by the age and gestation-related risk to derive the risk for trisomy 21 and trisomy 18. Detection rates (DRs) and false-positive rates (FPRs) were calculated by taking the proportions with risks above a given risk threshold. In screening with the algorithm for trisomy 21, at a FPR of 3%, the estimated DRs of trisomies 21 and 18 were 89% and 82%, respectively. The use of an algorithm for trisomy 18 identified 93% of affected fetuses at a FPR of 0.2%. When the algorithm for trisomy 21 was used and screen positivity was fixed at a FPR of 3%, and in addition the algorithm for trisomy 18 was used and screen positivity was fixed at a FPR of 0.2%, the overall FPR was 3.1% and the DRs of trisomies 21 and 18 were 90% and 97%, respectively. A beneficial side effect of first-trimester combined screening for trisomy 21 is the detection of a high proportion of fetuses with trisomy 18. If an algorithm for trisomy 18 in addition to the one for trisomy 21 is used, more than 95% of trisomy 18 fetuses can be detected with a minor increase of 0.1% in the overall FPR.

  1. Radioimmunoassay for pregnancy-associated plasma protein A

    Energy Technology Data Exchange (ETDEWEB)

    Sinosich, M.J. (Royal North Shore Hospital, Sidney, New South Wales, Australia); Teisner, B.; Folkerson, J.; Saunders, D.M.; Grudzinskas, J.G.

    1982-01-01

    A specific and highly sensitive radioimmunoassay for determination of pregnancy-associated plasma protein A in human serum is described. The minimum detection limit for this protein was 2.9 ..mu..g/L. The within- and between-assay coefficients of variation were 4.0 and 4.5%, respectively. The circulating protein was detected within 32 days of conception in eight normal pregnancies and within 21 days in a twin pregnancy. Circulating concentrations in the mother at term were consistently higher (10-fold) than in matched amniotic fluid; none was detected in the umbilical circulation. This protein was also detected in the circulation of patients with hydatidiform mole. This assay will permit investigations into the clinical evaluation of measurements of the protein during early pregnancy and trophoblastic disease.

  2. Free leptin index and PAPP-A: a first trimester maternal serum screening test for pre-eclampsia

    DEFF Research Database (Denmark)

    Hedley, Paula L; Placing, Sophie; Wøjdemann, Karen

    2010-01-01

    BACKGROUND: Prophylaxis with low-dose aspirin may reduce the risk of pre-eclampsia (PE) if introduced in first trimester. The performance of first trimester maternal serum screening for PE using free leptin index (fLI) and PAPP-A, where fLI = leptin/leptin soluble receptor was studied. METHODS...

  3. Association between plasma inflammatory markers and morphology of coronary artery lesion in patients with coronary artery disease

    Institute of Scientific and Technical Information of China (English)

    Xian Wang; Dayi Hu; Shiwei Yang; Jian Zhang; Tan Chen; Shouyan Zhang

    2008-01-01

    The atherosclerotic plaque vulnerability may be related to inflammation,immunity,metabolism and blood clotting.One of the key factors affecting plaque stability is inflammatory reaction.This study was to investigate the relationship between vulnerability of coronary artery plaque evaluated with coronary angiography (CAG),intravascular ultrasound (IVUS) and the levels of plasma inflammatory markers.Methods Fifty-eight consecutive patients with acute coronary syndrome who had coronary lesion of a single vessel were divided into 3 groups based on angiographic morphology of the lesions:type Ⅰ lesion group (n =16),type Ⅱ lesion group (n =25) and type Ⅲ lesion group (n =17).The control group consisted of 17 patients with stable angina.Plasma levels of high sensitivity C reaction protein (hs-CRP),matrix metalloproteinase (MMP,including MMP-2 and MMP-9),CD40 ligand (CD40L) and pregnancy associated plasma protein-A (PAPP-A) were measured by ELISA.A subgroup of 28 patients (including 18 ACS patients and 10 stable angina control patients) who underwent IVUS study,were analyzed.Results The plasma levels of MMP-2,MMP-9 and PAPP-A in type Ⅱ lesion group were significantly higher than those in other groups (all P<0.05).In type Ⅱ lesion group,linear correlation analyses showed significant positive correlation between levels of hs-CRP and MMP-2 (r=0.508);MMP-2 and MMP-9,CD40L,PAPP-A (r=0.647,0.704 and 0.751,respectively);MMP-9 and CD40L,PAPP-A (r=0.491 and 0.639,respectively);CD40L and PAPP-A (r=0.896).IVUS subgroup analysis showed that the area of plaques and plaque burden in culprit lesion,the incidence of high-risk plaques,remodeling index (RI) and positive remodeling percentage in ACS patients were significantly greater than those in control subgroup (P=0.000,0.037,0.028,0.015 and 0.040,respectively).Compared with control subgroup,the plasma levels of hs-CRP,MMP-2,MMP-9 and PAPP-A were markedly elevated (P=0.033,0.000,0.000 and 0.027,respectively).Conclusions CAG

  4. Level of Pregnancy-associated Plasma Protein-A,Cystatin C and Homocysteine in Pregnancy Induced Hypertension Patients and the Clinical Value%Medical Recapitulate

    Institute of Scientific and Technical Information of China (English)

    杨慧丽; 张秀欣

    2016-01-01

    目的:研究妊娠相关蛋白A( PAPP-A)、胱抑素C( CysC)、血同型半胱氨酸( Hcy)在妊娠期高血压疾病患者体内水平和其临床价值。方法选择2013年9月至2014年10月青岛市胶州中心医院收治的80例妊娠期高血压疾病患者作为研究组,另选30例正常妊娠妇女作为对照组。对两组收缩压、舒张压、心率等常规指标进行对比分析。依照观察组疾病类型分为妊娠期高血压、子痫、轻度先兆子痫、重度先兆子痫4个亚组,比较各组PAPP-A、CysC、Hcy水平差异。结果研究组患者收缩压、舒张压、心率、血尿酸均显著高于对照组[(166±20) mmHg(1 mmHg =0.133 kPa)比(131±15) mmHg、(108±20) mmHg 比(85±10) mmHg、(101±8)次/min 比(85±6)次/min、(383±63)μmol/L 比(310±52)μmol/L],白蛋白水平显著低于对照组[(30±7) g/L比(42±4) g/L],差异有统计学意义(P<0.05)。研究组PAPP-A、CysC、Hcy水平显著高于对照组[(37.0±7.7)μmol/L比(28.7±5.5)μmol/L、(1.5±0.4) mg/L 比(0.8±0.3) mg/L、(24.7±1.7)μmol/L 比(9.9±0.8)μmol/L],差异有统计学意义(P<0.05)。妊娠期高血压组、轻度先兆子痫组、重度先兆子痫组、子痫组患者PAPP-A、CysC、Hcy水平均依次升高,4组比较差异有统计学意义( P<0.05)。结论妊娠期高血压疾病患者血清中PAPP-A、CysC、Hcy水平均显著高于正常健康妊娠孕妇,病情越严重,其水平越高,对于妊娠期高血压疾病的临床诊治具有重要指导意义。%Objective To study the level of pregnancy associated protein A ( PAPP-A) ,serum cystatin C (Cys C),plasma homocysteine (Hcy) in patients with pregnancy induced hypertension and the clinical value. Methods Chosen from Sep.2013 to Oct.2014 in Qingdao Jiaozhou Central Hospital 80 cases of pregnancy

  5. First-trimester screening for chromosomal abnormalities by integrated application of nuchal translucency, nasal bone, tricuspid regurgitation and ductus venosus flow combined with maternal serum free β-hCG and PAPP-A: a 5-year prospective study.

    Science.gov (United States)

    Ghaffari, S R; Tahmasebpour, A R; Jamal, A; Hantoushzadeh, S; Eslamian, L; Marsoosi, V; Fattahi, F; Rajaei, M; Niroomanesh, S; Borna, S; Beigi, A; Khazardoost, S; Saleh-Gargari, S; Rahimi-Sharbaf, F; Farrokhi, B; Bayani, N; Tehrani, S E; Shahsavan, K; Farzan, S; Moossavi, S; Ramezanzadeh, F; Dastan, J; Rafati, M

    2012-05-01

    To investigate the performance of first-trimester screening for chromosomal abnormalities by integrated application of nuchal translucency thickness (NT), nasal bone (NB), tricuspid regurgitation (TR) and ductus venosus (DV) flow combined with maternal serum free β-human chorionic gonadotropin (fβ-hCG) and pregnancy-associated plasma protein-A (PAPP-A) at a one-stop clinic for assessment of risk (OSCAR). In total, 13,706 fetuses in 13,437 pregnancies were screened for chromosomal abnormalities during a period of 5 years. Maternal serum biochemical markers and maternal age were evaluated in combination with NT, NT + NB, NT + NB + TR, and NT + NB + TR + DV flow data in 8581, 242, 236 and 4647 fetuses, respectively. In total, 51 chromosomal abnormalities were identified in the study population, including 33 cases of trisomy 21, eight of trisomy 18, six of sex chromosome abnormality, one of triploidy and three of other unbalanced abnormalities. The detection rate and false-positive rate (FPR) for trisomy 21 were 93.8% and 4.84%, respectively, using biochemical markers and NT, and 100% and 3.4%, respectively, using biochemical markers, NT, NB, TR and DV flow. While risk assessment using combined biochemical markers and NT measurement has an acceptable screening performance, it can be improved by the integrated evaluation of secondary ultrasound markers of NB, TR and DV flow. This enhanced approach would decrease the FPR from 4.8 % to 3.4 %, leading to a lower number of unnecessary invasive diagnostic tests and subsequent complications, while maintaining the maximum level of detection rate. Pre- and post-test genetic counseling is of paramount importance in either approach. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.

  6. Screening for trisomy 21 by maternal age, fetal nuchal translucency thickness, free beta-human chorionic gonadotropin and pregnancy-associated plasma protein-A.

    Science.gov (United States)

    Kagan, K O; Wright, D; Baker, A; Sahota, D; Nicolaides, K H

    2008-06-01

    To derive a model and examine the performance of first-trimester combined screening by maternal age, fetal nuchal translucency (NT) thickness and maternal serum free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A). Prospective combined screening for trisomy 21 was carried out at 11 + 0 to 13 + 6 weeks in 56,771 singleton pregnancies, including 56,376 cases with a normal karyotype or delivery of a phenotypically normal baby (unaffected group) and 395 cases with trisomy 21. The blood test and ultrasound scan were carried out in the same visit. In each case the maternal age-related risk for trisomy 21 at term was calculated and adjusted according to the gestational age at the time of screening to derive the a-priori risk. The measured NT was transformed into a likelihood ratio using the mixture model of NT distributions. The measured free beta-hCG and PAPP-A were converted into a multiple of the median (MoM) for gestational age, adjusted for maternal weight, ethnicity, smoking status, method of conception and parity, and a likelihood ratio was subsequently calculated. The likelihood ratios for NT and for the biochemical markers were multiplied by the a-priori risk to derive the patient-specific risk. Detection rates and false-positive rates were calculated by taking the proportions with risks above a given risk threshold after adjustment for maternal age according to the distribution of pregnancies in England and Wales in 2000-2002. These standardized rates were compared with detection and false-positive rates estimated using Monte Carlo methods to sample from the modeled Gaussian distributions. The performance of screening based on the model was in good agreement with that observed in our population. In a strategy for first-trimester combined screening where the blood test and scan are carried out in the same visit it was estimated that, for false-positive rates of 3% and 5%, the detection rates were 92% and 94

  7. Transgenic overexpression of pregnancy-associated plasma protein-A in murine arterial smooth muscle accelerates atherosclerotic lesion development

    DEFF Research Database (Denmark)

    Conover, Cheryl A; Mason, Megan A; Bale, Laurie K

    2010-01-01

    of atherosclerotic lesions, we generated transgenic mice that express human PAPP-A in arterial smooth muscle. Four founder lines were characterized for transgenic human PAPP-A mRNA and protein expression, IGFBP-4 protease activity, and tissue specificity. In study I, apolipoprotein E knockout (ApoE KO) mice, a well...... from ApoE KO/Tg compared with ApoE KO mice (P smooth muscle of double ApoE KO/PAPP-A KO mice resulted in a 2.5-fold increase in lesion area (P = 0.002), without an effect...... on lesion number. PAPP-A transgene expression was associated with a significant increase in an IGF-responsive gene (P smooth muscle accelerates lesion progression in a mouse model...

  8. Usefulness of pregnancy-associated plasma protein A in patients with acute coronary syndrome

    DEFF Research Database (Denmark)

    Iversen, Kasper; Dalsgaard, Morten; Teisner, Ane S

    2009-01-01

    identify patients at high risk who would potentially benefit from intensive treatment and surveillance. Two populations of consecutive patients admitted with high-risk NSTE-ACS (n = 123) and STEMI (n = 314) were evaluated with serial measurements of PAPP-A. The incidence of mortality and nonfatal...... (STEMI), risk stratification is primarily determined by the markers of myocardial necrosis and known demographic risk profiles. However, it has recently been proposed that the presence and extent of vulnerable plaques might influence the prognosis significantly. A marker for the vulnerable plaque could...... myocardial infarction (odds ratio 2.65, 95% confidence interval 1.40 to 5.03) but not for mortality alone (p = NS). In patients with STEMI, PAPP-A was related to the risk of death (p = 0.01) but not the composite outcome of myocardial infarction and death. This was also true after adjustment for other...

  9. Early Pregnancy-Associated Plasma Protein A Concentrations are Associated with Third Trimester Insulin Sensitivity

    DEFF Research Database (Denmark)

    Petry, Clive J; Ong, Ken K; Hughes, Ieuan A

    2017-01-01

    -A concentrations are related to the subsequent risk of GDM and gestational hypertension. Patients, Design and Setting: We measured serum PAPP-A concentrations around week 15 of pregnancy and related these to indices derived from week 28 oral glucose tolerance tests (OGTT) and blood pressures across pregnancy...... in the Cambridge Baby Growth Study cohort. Results: Increased PAPP-A concentrations were associated with reduced GDM risk (odds ratio 0.623 (0.453, 0.856), P=3.5 x 10-3, n=777) and reduced mean arterial blood pressures (β=-0.202- -0.177, P=1.7-6.9 x 10-3, n=347-355). They were also negatively associated with week...

  10. The relationship of the expression of peripheral-blood sFIt-1,β-hCG, PAPP-A, AFP and early onset preeclampsia%外周血 sFIt-1、β-hCG、PAPP-A、AFP 的表达与早发型子痫前期的关系

    Institute of Scientific and Technical Information of China (English)

    杜娟; 朱一麟; 高雪梅; 贺漪

    2016-01-01

    trimester pregnancy associated plasma protein A ( PAPP-A) , alpha-fetoprotein ( AFP) and early onset preeclampsia ( PE) .Methods 84 cases of PE (48 cases of early on-set, late-onset 36 cases) were selected in our hospital from October 2014 to October 2015.Meanwhile,80 cases of normal pregnancy women were selected as the control group.The levels of peripheral-blood sFIt-1,β-hCG, PAPP-A, AFP of all pa-tients were measured by ELISA.The diagnostic value ofβ-hCG, PAPP-A, AFP of early-onset preeclampsia were analyzed by application-specific subjects curve (ROC).Results The levels of peripheral-blood sFIt-1,β-hCG, PAPP-A, AFP in the PE patients of early-onset group were all higher than the control group ( t =9.236, t =10.422, t =11.986, t =14.785, P 0.05).The levels of peripheral-blood sFIt-1,β-hCG, PAPP-A, AFP of early-onset severe PE were higher than mild group ( t =6.271, t =31.680, t =3.449, t =5.045, P <0.05), and there was no significant difference between the levels of peripheral-blood sFIt-1, PAPP-A, AFP of delayed severe patients and the mild group ( t =0.598, t =0.230, t =0.437, P <0.05), andβ-hCG was statistically sig-nificant( t =6.043, P <0.05).ROC analysis shows that the sensitivity and specificity of sFIt-1+β-hCG+PAPP-A+AFP joint diagnosis of early-onset PE were higher than single index detection.Conclusion There is a close relationship between periph-eral blood sFIt-1,β-hCG, PAPP-A, AFP levels and early-onset PE, and different pathogenesis may exist between early-onset and late-onset PE.It can enhance the diagnostic sensitivity of early-onset preeclampsia with combination of multiple indexes.

  11. 妊娠早中期孕妇血清中β-hCG、PAPP-A、AFP及uE3水平检测在联合预测子痫前期中的价值%The value of maternal first and second trimester serum data of β-hCG, PAPP-A, AFP and uE3 in the prediction of preeclampsia

    Institute of Scientific and Technical Information of China (English)

    顾玮; 林婧; 侯燕燕

    2015-01-01

    1831 mU/L、AFP 41μg/L及uE31.04μg/L,预测子痫前期的特异度分别为97.82%、98.54%及98.80%。(6)以PAPP-A、AFP及uE3的联合预测因子作为检验变量绘制ROC曲线并计算约登指数,联合预测因子为0.032时约登指数最大(为0.41),其预测子痫前期的价值最大。故以0.032作为PAPP-A、AFP及uE3联合预测因子的预测界值,其预测子痫前期的特异度为98.93%,敏感度为70.59%,相对风险度为2.37。结论无论是PAPP-A、AFP及uE3各单项血清指标还是联合预测因子,对子痫前期发病均有预测价值,但联合预测因子的预测价值要优于任一单项血清指标。%Objective To discover the value of combined maternal first and second-trimester serumβ-hCG, pregnancy associated plasma protein A (PAPP-A), alpha-fetoprotein(AFP)and unconjugated estriol (uE3) in the prediction of preeclampsia.Methods A total of 1 805 pregnant women who had antenatal care at International Peace Maternal and Child Health Hospital Affiliated to Shanghai Jiaotong University between April 2012 and June 2013 were selected prospectively by random method. According to the outcome, they were defined as the control group and the preeclampsia group (including mild and severe cases). PAPP-A and β-hCG level were measured at 10-14 gestational weeks. AFP, β-hCG and uE3 were measured at 15-20 gestational weeks. The relevance between the serological indicators and outcomes was analyzed. The value of the indicators was judged by receiver operating characteristic(ROC)and Youden index, and the relevant predictive boundary values were identified.Results (1) Among the 1 805 cases, 1 739 women did not have hypertension(the control group), while 66 women had preeclampsia(the preeclampsia group). The incidence of preeclampsia was 3.66% (66/1 805), including 43 mild cases and 23 severe cases. (2) At 10-14 gestational weeks, the mean value of PAPP-A in the control group was(3 972± 2 311) mU/L, while in the

  12. Plasma concentrations of four pregnancy proteins in complications of pregnancy.

    Science.gov (United States)

    Lin, T M; Halbert, S P; Spellacy, W N; Berne, B H

    1977-08-01

    Toxemia of pregnancy was associated with an elevation of the pregnancy-associated plasma protein (PAPP)-A concentration, as compared to the level in normal pregnancy in the last month of gestation. The other pregnancy proteins measured were not altered in toxemia. In twin pregnancies, the PAPP-A, PAPP-C, and human placental lactogen levels were all increased, particularly PAPP-A. On the other hand, pregnancy zone protein was not affected by twinning. Pregnancy with diabetes showed normal levels of these proteins.

  13. Analysis of the impact of PAPP-A, free β-hCG and nuchal translucency thickness on the advanced first trimester screening.

    Science.gov (United States)

    Berktold, L; von Kaisenberg, C S; V Kaisenberg, C; Hillemanns, P; Vaske, B; Schmidt, P

    2013-03-01

    The intention of this study is to analyze the impact of the single parameters NT, PAPP-A and free β-hCG used in combined first trimester screening and to determine their contribution in the risk assessment. A retrospective risk assessment on the advanced first trimester screening (AFS) algorithm was made to determine the effect of a particular parameter while the remaining ones were fixed for calculation. Afterward data were recalculated by the AFS module. Test performance was measured by receiver operating characteristics (ROC) curves and their area under curve (AUC). Among the 14,862 cases are 14,748 healthy fetuses, 86 with trisomy 21, 22 with trisomy 18 and 6 with trisomy 13. Some settings obtain at default cut-off a very high sensitivity. However, a lack of specificity, as a high false-positive rate, too. The ROC analysis was best for NT, followed by PAPP-A. Free β-hCG showed the lowest AUC. Combining PAPP-A and free β-hCG offered a better AUC than each parameter alone. Best test performance was obtained by including all three parameters. A detection rate of 69 % for testing NT discretely is in order with present study data. PAPP-A is following and free β-hCG is not useful with a test positive rate of about a third. The detection rate of the biochemical parameters combined is higher than for NT alone, but results in a five times higher punctuation rate. All parameters together in the AFS provide the best test performance. The impact of each parameter NT, PAPP-A and free-β-hCG in a combined test strategy is nearly a third. Thus, every single parameter is needed to provide a high detection rate for all of the trisomies and minimize the number of unnecessary invasive diagnostics.

  14. Fluorescence Enhancement of Fluorescein Isothiocyanate-Labeled Protein A Caused by Affinity Binding with Immunoglobulin G in Bovine Plasma

    Directory of Open Access Journals (Sweden)

    Kiyotaka Sakai

    2009-10-01

    Full Text Available Fluorescence enhancement of fluorescein isothiocyanate-labeled protein A (FITC-protein A caused by the binding with immunoglobulin G (IgG in bovine plasma was studied. FITC-protein A was immobilized onto a glass surface by covalent bonds. An increase in fluorescence intensity was dependent on IgG concentration ranging from 20 to 78 μg/mL in both phosphate buffer saline and bovine plasma. This method requires no separation procedure, and the reaction time is less than 15 min. A fluorescence enhancement assay by the affinity binding of fluorescence-labeled reagent is thus available for the rapid determination of biomolecules in plasma.

  15. Leukocyte Counts, Myeloperoxidase, and Pregnancy-Associated Plasma Protein A as Biomarkers for Cardiovascular Disease: Towards a Multi-Biomarker Approach

    Directory of Open Access Journals (Sweden)

    M. B. I. Lobbes

    2010-01-01

    Full Text Available We evaluated leukocyte counts and levels of CRP, fibrinogen, MPO, and PAPP-A in patients with stable and unstable angina pectoris, acute myocardial infarction, and healthy controls. All biomarkers were analyzed again after 6 months. Leukocyte counts and concentrations of fibrinogen, CRP, MPO, and PAPP-A were significantly increased in patients with acute myocardial infarction. Leukocyte counts and concentrations of MPO were significantly increased in patients with unstable angina pectoris compared with controls. After 6 months, leukocyte counts and MPO concentrations were still increased in patients with acute myocardial infarction when compared to controls. Discriminant analysis showed that leukocyte counts, MPO, and PAPP-A concentrations classified study group designation for acute coronary events correctly in 83% of the cases. In conclusion, combined assessment of leukocyte counts, MPO, and PAPP-A was able to correctly classify acute coronary events, suggesting that this could be a promising panel for a multibiomarker approach to assess cardiovascular risk.

  16. A first trimester trisomy 13/trisomy 18 risk algorithm combining fetal nuchal translucency thickness, maternal serum free beta-hCG and PAPP-A.

    Science.gov (United States)

    Spencer, Kevin; Nicolaides, Kypros H

    2002-10-01

    This study examines 45 cases of trisomy 13 and 59 cases of trisomy 18 and reports an algorithm to identify pregnancies with a fetus affected by trisomy 13 or 18 by a combination of maternal age fetal nuchal translucency (NT) thickness, and maternal serum free beta-hCG and PAPP-A at 11-14 weeks of gestation. In this mixed trisomy group the median MoM NT was increased at 2.819, whilst the median MoMs for free beta-hCG and PAPP-A were reduced at 0.375 and 0.201 respectively. We predict that with the use of the combined trisomy 13 and 18 algorithm and a risk cut-off of 1 in 150 will for a 0.3% false positive rate allow 95% of these chromosomal defects to be identified at 11-14 weeks. Such algorithms will enhance existing first trimester screening algorithms for trisomy 21. Copyright 2002 John Wiley & Sons, Ltd.

  17. Release patterns of pregnancy-associated plasma protein A in patients with acute coronary syndromes assessed by an optimized monoclonal antibody assay

    DEFF Research Database (Denmark)

    Schoos, Mikkel; Iversen, Kasper; Teisner, Ane;

    2008-01-01

    of ACS. Methods. In 40 patients, PAPP-A concentrations were measured in serially collected samples assessed by a novel ELISA technique. The patients were grouped according to type of ACS. Results. Release patterns for ST elevation myocardial infarction (STEMI) patients who underwent primary percutaneous...

  18. Prospective evaluation of first trimester combined screening for trisomy 21 using a double set of the maternal serum markers PAPP-A and free β-hCG

    DEFF Research Database (Denmark)

    Ekelund, Charlotte Kvist; Wright, Dave; Ball, Susan

    Objective: To prospectively evaluate the screening performance of first trimester combined screening for trisomy 21 using a double set of biochemical markers Methods: Three fetal medicine departments in Denmark participated in the study. Screening for trisomy 21 was set up as a two-step approach...... with an early blood sample taken prior to the NT scan, and another blood sample taken at the time of the NT scan. PAPP-A and free β-hCG were measured on both the early and the late samples, and Multiples of the Median (MoM) values were calculated in addition to the corresponding trisomy 21 risk. Using...... statistical modelling we estimated detection rates (DR) and false positive rates (FPR) when using early sampling, late sampling or combinations of early and late sampling. Results: We collected two blood samples in 25 pregnancies affected by trisomy 21 and in 3942 control pregnancies. The early samples were...

  19. Longer time-to-pregnancy in spontaneously conceived pregnancies is associated with lower PAPP-A and free β-hCG in first trimester screening for Down syndrome

    DEFF Research Database (Denmark)

    Kirkegaard, I.; Uldbjerg, N.; Tabor, Ann

    2014-01-01

    -hCG) and hence the risk estimates in Down syndrome screening. METHODS: The study included a cohort of 10 469 singleton pregnant women who underwent first trimester combined screening and responded to a questionnaire regarding TTP. PAPP-A and free β-hCG levels were measured between gestational week 8 + 0 and 13...

  20. Effect of the PAPP-A on left ventricular hypertrophy and the intervention of γ-interferon in the spontaneously hypertensive rat%妊娠相关蛋白-A对自发性高血压大鼠左室肥厚的影响及γ-干扰素的干预作用

    Institute of Scientific and Technical Information of China (English)

    范剑峰; 郑春华; 汤圣兴; 高招波; 万明勇; 张春花; 张雪梅

    2011-01-01

    Objective:To observe the effect of pregnancy-associated plasma protcin-A (PAPP-A) on lcft ventricular hypertrophy (LVH) and the intervention of γ-interferon (INFy) in the spontaneously hypertcnsive rat (SHR). Method: Twenty-eight SHR were randomly divided into 4 groups (n = 7) : high-dose group (SHR-H) ,middle dose group (SHR-M) , low-dose group (SHR-L) and the SHR control group (SHR-C). SHRL, SHR-M and SHR-H wcre injected INF-γ respectively for 8 wecks. SHR-C group and WKY group [7 Wistar-Kyoto (WKY) rats were selccted as WKY control group (WKY, n=7)] were injected normal saline for 8 weeks. The tail arterial systolic blood pressure (SBP) of the rats and the level of PPAPA wcre measurcd at the time of pretherapy, 4 week of the treatment and 8 week. At the eighth week, they were sacrificed. We weighed the left ventricular of the hearts and calculated the left ventricular wcight index. We observed the morphological changes in myocardial tissue with HF staining. The expression of PAPPA protein was analysed by Western blot. Result: ①At the time of pre-therapy, the different of SBP and PAPP-A was significantly higher in all SHR group than WKY group (P<0. 05). After 4 weeks, SBP and PAPP-A in SHR-H group and after 8 weeks, SBP and PAPP-A in SHR-M was significantly lower than SHR-C group of the same time (P<0. 05) : but significantly higher than WKY group (P<0. 05).②LVW and LVMI in all SHR group was significantly highcr than WKY group (P<0.05). LVW and LVMI was dccrcascd significantly after using high doses of INF- γ.③To observe HE staincd sections by optical microscope: the normal myocardial cells, non-mesenchymal cells hyperplasia in WKY group. My ocardial cells and fibers was disorder in SHR group. This change of histology was inhibited in all group by using INF-γ with the most effective in high-dose group. ④The correlation analysis of PAPP-A and LVMI showed that they had a significant positive correlation (R =0. 911, P<0. 05).⑤Comparison with

  1. Plasma soluble prion protein, a potential biomarker for sport-related concussions: a pilot study.

    Directory of Open Access Journals (Sweden)

    Nam Pham

    Full Text Available Sport-related mild traumatic brain injury (mTBI or concussion is a significant health concern to athletes with potential long-term consequences. The diagnosis of sport concussion and return to sport decision making is one of the greatest challenges facing health care clinicians working in sports. Blood biomarkers have recently demonstrated their potential in assisting the detection of brain injury particularly, in those cases with no obvious physical injury. We have recently discovered plasma soluble cellular prion protein (PrP(C as a potential reliable biomarker for blast induced TBI (bTBI in a rodent animal model. In order to explore the application of this novel TBI biomarker to sport-related concussion, we conducted a pilot study at the University of Saskatchewan (U of S by recruiting athlete and non-athlete 18 to 30 year-old students. Using a modified quantitative ELISA method, we first established normal values for the plasma soluble PrP(C in male and female students. The measured plasma soluble PrP(C in confirmed concussion cases demonstrated a significant elevation of this analyte in post-concussion samples. Data collected from our pilot study indicates that the plasma soluble PrP(C is a potential biomarker for sport-related concussion, which may be further developed into a clinical diagnostic tool to assist clinicians in the assessment of sport concussion and return-to-play decision making.

  2. Plasma soluble prion protein, a potential biomarker for sport-related concussions: a pilot study.

    Science.gov (United States)

    Pham, Nam; Akonasu, Hungbo; Shishkin, Rhonda; Taghibiglou, Changiz

    2015-01-01

    Sport-related mild traumatic brain injury (mTBI) or concussion is a significant health concern to athletes with potential long-term consequences. The diagnosis of sport concussion and return to sport decision making is one of the greatest challenges facing health care clinicians working in sports. Blood biomarkers have recently demonstrated their potential in assisting the detection of brain injury particularly, in those cases with no obvious physical injury. We have recently discovered plasma soluble cellular prion protein (PrP(C)) as a potential reliable biomarker for blast induced TBI (bTBI) in a rodent animal model. In order to explore the application of this novel TBI biomarker to sport-related concussion, we conducted a pilot study at the University of Saskatchewan (U of S) by recruiting athlete and non-athlete 18 to 30 year-old students. Using a modified quantitative ELISA method, we first established normal values for the plasma soluble PrP(C) in male and female students. The measured plasma soluble PrP(C) in confirmed concussion cases demonstrated a significant elevation of this analyte in post-concussion samples. Data collected from our pilot study indicates that the plasma soluble PrP(C) is a potential biomarker for sport-related concussion, which may be further developed into a clinical diagnostic tool to assist clinicians in the assessment of sport concussion and return-to-play decision making.

  3. Associations between the plasma inflammatory markers and plaque morphologies of coronary artery lesions%冠状动脉斑块形态学与血浆炎症介质的关系

    Institute of Scientific and Technical Information of China (English)

    王显; 胡大一; 杨士伟; 张健; 谭琛; 张守彦

    2008-01-01

    objective To evaluate the vulnerability of coronary artery plaque with coronary angiography(CAG),intravascular ultrasound(IVUS)and the levels of plasma inflammatory markers.Methods 58 consecutive patients with lesion of a single blood vessel demonstrated successfully by CAG were randomly divided into 3 groups based on the angiographic morphology of the the lesions:type Ⅰ lesion group(n=16),type Ⅱ lesion group(n=25),type Ⅲ lesion group(n=17).Meantime,a control group of stable angina(n=17)was established.A subgroup of 28 patients(including 18 acute coonary sysdrome (ACS)patients and 10 stable angina control patients)who underwent IVUS study were analyzed.Then the plasma levels of high sensitivity CRP(hs-CRP),matrix metalloproteinase(MMP,including MMP-2 and MMP-9),CD40 ligand(CD40 L)and pregnancy associated plasma protein-A(PAPP-A)were measured with ELISA.Analyses were performed by statistical package SPSS 11.0.Results The plasma levels of MMP-2,MMP-9 and PAPP-A in typeⅡ lesion group were significantly higher than the other groups(P<0.05,0.05,0.001,respectively).In type Ⅱ lesion group,linear correlation analysis manifested significantly positive correlation between levels of hs-CRP and MMP-2(r=0.508);MMP-2 and MMP-9,CD40 L,PAPP-A(r=0.647,0.704,0.751,respectively);MMP-9 and CD40L,PAPP-A(r=0.491,0.639,respectively);CD40L and PAPP-A(r=0.896).IVUS subgroup analysis showed that the area of plaques and plaques burden in culprit lesion,the incidence of high-risk plaques,remodeling index(RI)and positive remodeling percentage in ACS patients were significantly greater than those in the control group(P=0.000,0.037,0.028,0.015,0.040,respectively).Compared with the control group,the plasma levels of hs-CRP,MMP-2,MMP-9 and PAPP-A were markedly elevated(P=0.033,0.000,0.000,0.027,respectively).Conclusions CAG and IVUS combined with the study on plasma levels of inflammation mediators were helpful in judging the vulnerability of coronary artery plaques.%目的 从冠状

  4. Protein secretion is required for pregnancy-associated plasma protein-A to promote lung cancer growth in vivo.

    Directory of Open Access Journals (Sweden)

    Hong Pan

    Full Text Available Pregnancy-associated plasma protein-A (PAPPA has been reported to regulate the activity of insulin-like growth factor (IGF signal pathway through proteolytic degradation of IGF binding proteins (IGFBPs thereby increasing the local concentration of free IGFs available to receptors. In this study we found that PAPPA is secreted from two out of seven lung cancer cell lines examined. None of immortalized normal bronchial epithelial cells (HBE tested secrets PAPPA. There is no correlation between expression level and secretion of PAPPA in these cells. A cell line over-expressing PAPPA accompanied with secretion shows no notable changes in proliferation under cell culture conditions in vitro, but displays significantly augmentation of tumor growth in vivo in a xenograft model. In contrast, a cell line over-expressing PAPPA without secretion exhibits reduction of tumor growth both in vitro and in vivo. Down-regulation of PAPPA expression and secretion by RNAi knockdown decreases tumor growth after implanted in vivo. The tumor promoting activity of PAPPA appears to be mediated mainly through augmentation of the IGF signaling pathway as indicated by notable increases in downstream Akt kinase phosphorylation in tumor samples. Our results indicate that PAPPA secretion may play an important role in lung cancer growth and progression.

  5. The impact of fetal gender on first trimester nuchal translucency and maternal serum free beta-hCG and PAPP-A MoM in normal and trisomy 21 pregnancies.

    Science.gov (United States)

    Cowans, Nicholas J; Stamatopoulou, Anastasia; Maiz, Nerea; Spencer, Kevin; Nicolaides, Kypros H

    2009-06-01

    To investigate if fetal sex has an impact on 1st trimester combined screening for aenuploidy. We studied the first trimester PAPP-A, free beta-human chorionic gonadatropin (beta-hCG) and nuchal translucency levels in 56,024 normal, singleton pregnancies with known fetal sex at birth. We also examined the distributions in 722 pregnancies with trisomy 21 of known fetal sex. We have found a 14.74% increase in first trimester maternal serum (MS) median free beta-hCG MoM, 6.25% increase of PAPP-A and a 9.41% decrease in delta NT, when the fetus was female. Analysis of data has shown that women carrying a female fetus were 1.084 times more likely to be in the 'at risk' group than those carrying a male fetus. In examining data from 722 pregnancies in which the fetus was affected by trisomy 21, we observed a similar 20.8% increase in free beta-hCG MoM, 5.7% increase in PAPP-A and a 12% decrease in delta NT when the fetus was female. Amongst the trisomy 21 cases, 88.8% of male trisomy 21 cases were detected compared with 91.2% in female cases, this difference was not statistically significant. Correcting for fetal sex redressed the balance in screen-positive rate between the sexes and had a minimal impact on detection rate. Correcting for fetal sex may be a worthwhile consideration. A cost-benefit analysis would be required to determine if it is feasible to introduce fetal gender assignment into the routine first trimester scan for the purpose of marker correction and whether this would have any significant impact. (c) 2009 John Wiley & Sons, Ltd.

  6. Maternal weight correction of maternal serum PAPP-A and free beta-hCG MoM when screening for trisomy 21 in the first trimester of pregnancy.

    Science.gov (United States)

    Spencer, Kevin; Bindra, Renu; Nicolaides, Kypros H

    2003-10-01

    To assess the suitability of either the log-linear or reciprocal-linear regression procedure for maternal weight correction of biochemical marker MoMs in the first trimester. Data from two prospective first-trimester OSCAR screening programmes including 32,010 women with first-trimester maternal serum-free beta-hCG and PAPP-A measured by the Kryptor analyser was analysed by regression analysis to provide parameters for the log-linear and reciprocal-linear MoM correction procedures. Assessment was made by goodness of fit to the data. The impact on detection rate and false-positive rate of the different correction procedures was assessed using statistical modelling with biochemical markers alone. Both log-linear and reciprocal-linear correction were shown to fit the data well. For free beta-hCG, the log-linear procedure was marginally superior to the reciprocal-linear procedure (r2=0.986 v 0.980), whilst for PAPP-A the reciprocal-linear procedure was marginally better (r2=0.991 v 0.985). Log-linear correction reduced the variance for both markers more than did the reciprocal-linear procedure. For free beta-hCG, the sd was reduced from 0.2675 to 0.2605 and for PAPP-A, it was reduced from 0.2545 to 0.2336. Correcting for maternal weight was shown to reduce the population false-positive rate from 7.0 to 6.5%, whilst maintaining the same detection rate at a risk cut-off of 1 in a 100. At individual levels, a two-fold variation in risk was demonstrated depending upon the individual's weight. To provide accurate individual patient-specific risks for trisomy 21, maternal weight must be taken into account and should be a mandatory data item for screening programmes. Maternal weight correction in the first trimester using free beta-hCG and PAPP-A can be best achieved using the log-linear procedure. Copyright 2003 John Wiley & Sons, Ltd.

  7. Relationship between pregnancy associated plasma protein A,VEGF and hypertension during pregnancy%妊娠相关血浆蛋白A、VEGF与妊高症关系

    Institute of Scientific and Technical Information of China (English)

    李巧红; 侯爱琴

    2015-01-01

    Objective: To investigate the relationship between PAPP-A and VEGF in pregnancy induced hypertension syndrome.Methods:50 cases of PIH pregnant women as the study group, while 50 healthy pregnant women as control group. The patients with hypertension were divided into three groups according to the severity of the disease, in which the contents of VEGF and PAPP-A were compared.Results: PAPP-A was signiifcantly higher in the patients with pregnancy induced hypertension than in the control group, the difference was statistically signiifcant, with the increase of the degree of pregnancy induced hypertension, PAPP-A was also increased. VEGF was significantly higher in the patients with pregnancy induced hypertension than in the control group, the difference was statistically signiifcant, but there was no signiifcant difference between the groups in the three groups, no signiifcant change trend.Conclusion: The contents of PAPP-A and VEGF in pregnant women with pregnancy induced hypertension, and PAPP-A was positively correlated with the severity of hypertension. VEGF and PAPP-A were used as the indexes for the monitoring of pregnancy induced hypertension.%目的:探讨妊娠相关血浆蛋白A(PAPP-A)、VEGF对妊娠高血压综合症关系诊断价值。方法:选择50例妊高症孕妇为研究组,另选50例正常孕妇为对照组。妊高症组按照严重程度分为轻、中、重三组,比较各组PAPP-A、VEGF含量。结果:妊高症组PAPP-A显著高于对照组,组间比较差异有统计学意义,随妊高症程度升高,PAPP-A亦呈增高趋势。妊高症组VEGF显著高于对照组,组间比较差异有统计学意义,但轻中重三组VEGF组间比较差异无统计学意义,无明显变化趋势。结论:妊娠高血压综合症孕妇其PAPP-A、VEGF含量升高,且PAPP-A与妊高症严重程度呈正相关,PAPP-A、VEGF含量可以作为妊高症监测指标。

  8. The influence of fetal sex in screening for trisomy 21 by fetal nuchal translucency, maternal serum free beta-hCG and PAPP-A at 10-14 weeks of gestation.

    Science.gov (United States)

    Spencer, K; Ong, C Y; Liao, A W; Papademetriou, D; Nicolaides, K H

    2000-08-01

    In a study of 2923 normal pregnancies and 203 pregnancies affected by trisomy 21 we have shown a significant difference in the median MoM of the markers: fetal nuchal translucency, maternal serum free beta-hCG and PAPP-A in the presence of a female fetus compared with a male fetus. For maternal serum free beta-hCG levels are higher by 15% if the fetus is chromosomally normal and by 11% if the fetus has trisomy 21. For maternal serum PAPP-A the levels in chromosomally normal fetuses are 10% higher in the presence of a female fetus and 13% higher if the fetus has trisomy 21. In contrast, fetal nuchal translucency is 3-4% lower in both chromosomally normal and trisomy 21 female fetuses. The consequence of such changes when screening for trisomy 21 will be a reduction in the detection rate in female fetuses by a factor of 1-2%. Correction of risk algorithms for fetal sex, however, is probably not feasible, since ultrasound detection of fetal sex is only 70-90% accurate in the 10-14 week period. Copyright 2000 John Wiley & Sons, Ltd.

  9. Serum changes of pregnancy-associated plasma protein-A, vascular endothelial growth factor and their correlation in preeclampsia%PAPP-A及VEGF在子痫前期患者血清中的表达及其相关性研究

    Institute of Scientific and Technical Information of China (English)

    顾佳士; 邱丽华; 戴海燕

    2016-01-01

    Objective To investigate the serum changes of pregnancy-associated plasma protein-A (PAPP-A), vascular endothelial growth factor (VEGF) in patients with preeclampsia, and to analyze their correlation with the severi-ty of disease. Methods From January 2013 to December 2014, 90 pregnant women who had prenatal examinations and delivered in the Department of Obstetrics, Shanghai Pudong Hospital were recruited, including 60 patients with pre-eclampsia (PE group) and 30 healthy pregnant women (control group). The 60 patients with PE were divided into severe PE group (n=30) and mild PE group (n=30) according to the severity of the disease. Enzyme-linked immunosorbent as-say (ELISA) was used to determine the serum concentrations of PAPPA-A and VEGF. The correlations between the ex-pression of serum PAPPA-A, VEGF and the severity of the disease were analyzed. Results The newborn birth weight of the severe PE group [(3.4 ± 0.5) kg] were less than that of the mild PE group [(3.6 ± 1.4) kg] and control group [(3.7 ± 0.5) kg], and the differences were statistically significant (P<0.05). The serum levels of PAPPA-A, VEGF and 24 hours urinary protein in the severe PE group [(900.6±379.0)μg/ml, (7.2±4.2) pg/ml, (2.5±1.2) g/24 h] and the mild PE group [(783.8 ± 204.7) μg/ml, (5.3 ± 1.4) pg/ml, (1.4 ± 0.3) g/24 h] were significantly higher than those in the control group [(592.9±222.9)μg/ml, (4.8±2.8) pg/ml, (0.2±0.1) g/24 h], P<0.05. The serum level of PAPPA-A and the 24 hours urinary protein in the severe PE group were higher than those in the mild PE group (P<0.05). Spearman's correlation analysis showed that the serum level of PAPPA-A was positively correlated with the serum concentration of VEGF (P<0.05). Conclusion PAPPA and VEGF are involved in the occurrence and development of preeclampsia.%目的 观察子痫前期患者血清中妊娠相关血浆蛋白A (PAPP-A)及血清血管内皮生长因子(VEGF)表达情况,探讨其与子痫前期病

  10. Biological variation of free β chorionic gonadotropin and pregnancy-associated plasma protein A in first trimester pregnancies

    DEFF Research Database (Denmark)

    Sennels, Henriette P; Jørgensen, Finn Stener; Sørensen, Steen

    2011-01-01

    Abstract Background: Trisomy 21 risk estimation in first trimester pregnancies can be performed by a combined test based on ultrasound measurement of fetal nuchal translucency thickness and maternal plasma concentrations of free ß human chorionic gonadotropin (hCGß) and pregnancy-associated plasma...

  11. Biological variation of free β chorionic gonadotropin and pregnancy-associated plasma protein A in first trimester pregnancies

    DEFF Research Database (Denmark)

    Sennels, Henriette P; Jørgensen, Finn Stener; Sørensen, Steen

    2011-01-01

    Abstract Background: Trisomy 21 risk estimation in first trimester pregnancies can be performed by a combined test based on ultrasound measurement of fetal nuchal translucency thickness and maternal plasma concentrations of free β human chorionic gonadotropin (hCGβ) and pregnancy-associated plasma...

  12. The impact of temporal variability of biochemical markers PAPP-A and free β-hCG on the specificity of the first-trimester Down syndrome screening: a Croatian retrospective study

    Science.gov (United States)

    2010-01-01

    Background The variability of maternal serum biochemical markers for Down syndrome, free β-hCG and PAPP-A can have a different impact on false-positive rates between the 10+0 and 13+6 week of gestation. The study population comprised 2883 unaffected, singleton, spontaneously conceived pregnancies in Croatian women, who delivered apparently healthy child at term. Women were separated in 4 groups, dependently on the gestational week when the analyses of biochemical markers were performed. The concentrations of free β-hCG and PAPP-A in maternal serum were determined by solid-phase, enzyme-labeled chemiluminiscent immunometric assay (Siemens Immulite). Concentrations were converted to MoMs, according to centre-specific weighted regression median curves for both markers in unaffected pregnancies. The individual risks for trisomies 21, 18 and 13 were computed by Prisca 4.0 software. Findings There were no significant differences between the sub-groups, regarding maternal age, maternal weight and the proportion of smokers. The difference in log10 MoM free β-hCG values, between the 11th and 12th gestational week, was significant (p = 0.002). The difference in log10 MoM PAPP-A values between the 11th and 12th, and between 12th and 13th week of gestation was significant (p = 0.006 and p = 0.003, respectively). False-positive rates of biochemical risk for trisomies were 16.1% before the 11th week, 12.8% in week 12th, 11.9% in week 13th and 9.9% after week 13th. The differences were not statistically significant. Conclusions Biochemical markers (log10 MoMs) showed gestation related variations in the first-trimester unaffected pregnancies, although the variations could not be attributed either to the inaccuracy of analytical procedures or to the inappropriately settled curves of median values for the first-trimester biochemical markers. PMID:20630069

  13. A substrate specificity-determining unit of three Lin12-Notch repeat modules is formed in trans within the pappalysin-1 dimer and requires a sequence stretch C-terminal to the third module

    DEFF Research Database (Denmark)

    Weyer, Kathrin; Boldt, Henning B; Poulsen, Christine B

    2007-01-01

    Members of the pappalysin family of metzincin metalloproteinases, pregnancy-associated plasma protein-A (PAPP-A, pappalysin-1) and PAPP-A2 (pappalysin-2), regulate the bioavailability of insulin-like growth factors (IGFs) by specific proteolytic inactivation of IGF-binding proteins (IGFBPs). PAPP...

  14. Serum concentrations of the biomarkers CA125, CA15-3, CA72-4, tPSA and PAPP-A in natural and stimulated ovarian cycles

    Institute of Scientific and Technical Information of China (English)

    Melissa Stemp; Peter Roberts; Allison McClements; Vincent Chapple; Jay Natalwala; Michael Black; Phillip Matson

    2014-01-01

    Objective:Biomarkers associated with cancer screening (CA125, CA15‐3, CA72‐4, total prostate specific antigen [tPSA]) and the monitoring of pregnancy (pregnancy associated plasma protein‐A [PAPP‐A]) were measured during natural and stimulated ovarian cycles in disease‐free non-pregnant women to determine if they could reflect normal events relating to ovulation and/or endometrial changes. Methods: A total of 73 blood samples (10 women) collected throughout the natural menstrual cycle, and 64 blood samples (11 women) taken during stimulated ovarian cycles, were analysed on the Roche Cobas e411 automated analyser. Results:Detectable levels of tPSA were measured in at least one point in the cycle in 6/10 of women in the natural cycle and 10/11 of women in stimulated cycles, and CA72-4 was detected in only 12/21 women tested. Concentrations of CA125, tPSA, CA15‐3 and CA72‐4 showed no significant difference between the natural and stimulated ovarian cycle groups. On average the mean PAPP‐A of the natural group was (2.41±0.58) mIU/L higher than the stimulated group (t=4.10, P< 0.001). CA125 and CA15‐3 results were both significantly influenced by the stage of the cycle (P<0.0001), whereas tPSA and PAPP‐A concentrations revealed no significant changes (P≥0.65). CA72‐4 was not affected by the stage of the cycle nor ovarian stimulation. Conclusion:Ovarian stimulation reduced serum PAPP‐A levels, CA125 and CA15‐3 levels were generally unaffected by ovarian stimulation but displayed cyclical changes throughout both natural and stimulated cycles, whilst tPSA and CA72-4 were not affected by the stage of the cycle or ovarian stimulation.

  15. Regulation of pregnancy-associated plasma protein A2 (PAPPA2 in a human placental trophoblast cell line (BeWo

    Directory of Open Access Journals (Sweden)

    Christians Julian K

    2011-04-01

    Full Text Available Abstract Background Pregnancy-associated plasma protein A2 (PAPPA2 is an insulin-like growth factor-binding protein (IGFBP protease expressed at high levels in the placenta and upregulated in pregnancies complicated by preeclampsia and HELLP (Hemolytic anemia, Elevated Liver enzymes, and Low Platelet count syndrome. However, it is unclear whether elevated PAPPA2 expression causes abnormal placental development, or whether upregulation compensates for placental pathology. In the present study, we investigate whether PAPPA2 expression is affected by hypoxia, oxidative stress, syncytialization factors or substances known to affect the expression of PAPPA2's paralogue, PAPPA. Methods BeWo cells, a model of placental trophoblasts, were treated with one of the following: hypoxia (2% O2, oxidative stress (20 microM hydrogen peroxide, forskolin (10 microM and 100 microM, TGF-beta (10 and 50 ng/mL, TNF-alpha (100 ng/mL, IL-1beta (100 ng/mL or PGE2 (1 microM. We used quantitative RT-PCR (qRT-PCR to quantify the mRNA levels of PAPPA2, as well as those of PAPPA and ADAM12 since these proteases have similar substrates and are also highly expressed in the placenta. Where we observed significant effects on PAPPA2 mRNA levels, we tested for effects at the protein level using an in-cell Western assay. Results Hypoxia, but not oxidative stress, caused a 47-fold increase in PAPPA2 mRNA expression, while TNF-alpha resulted in a 6-fold increase, and both of these effects were confirmed at the protein level. PGE2 resulted in a 14-fold upregulation of PAPPA2 mRNA but this was not reflected at the protein level. Forskolin, TGF-beta and IL-1beta had no significant effect on PAPPA2 mRNA expression. We observed no effects of any treatment on PAPPA or ADAM12 expression. Conclusion Our study demonstrates that factors previously known to be highly expressed in preeclamptic placentae (PGE2 and TNF-alpha, contribute to the upregulation of PAPPA2. Hypoxia, known to occur in

  16. Assignment of the human gene for pregnancy-associated plasma protein A (PAPPA) to 9q33.1 by fluorescence in situ hybridization to mitotic and meiotic chromosomes

    DEFF Research Database (Denmark)

    Silahtaroglu, A N; Tümer, Z; Kristensen, Torsten;

    1993-01-01

    Low levels of pregnancy-associated plasma protein A (PAPPA) during the first trimester has been suggested as a biochemical indicator of pregnancies with aneuploid fetuses. Furthermore, the complete absence of PAPPA in pregnancies associated with Cornelia de Lange syndrome (CL) has suggested a cau...... a causal connection between PAPPA and the development of CL. We have assigned the locus for PAPPA to chromosome region 9q33.1 on mitotic and meiotic chromosomes by fluorescence in situ hybridization, using a 3.7-kb partial PAPPA cDNA probe...

  17. Assignment of the human gene for pregnancy-associated plasma protein A (PAPPA) to 9q33.1 by fluorescence in situ hybridization to mitotic and meiotic chromosomes

    DEFF Research Database (Denmark)

    Silahtaroglu, A N; Tümer, Z; Kristensen, Torsten

    1993-01-01

    Low levels of pregnancy-associated plasma protein A (PAPPA) during the first trimester has been suggested as a biochemical indicator of pregnancies with aneuploid fetuses. Furthermore, the complete absence of PAPPA in pregnancies associated with Cornelia de Lange syndrome (CL) has suggested a cau...... a causal connection between PAPPA and the development of CL. We have assigned the locus for PAPPA to chromosome region 9q33.1 on mitotic and meiotic chromosomes by fluorescence in situ hybridization, using a 3.7-kb partial PAPPA cDNA probe...

  18. Effect of the binding interaction of an emissive niacin derivative on the conformation and activity of a model plasma protein: A spectroscopic and simulation-based approach.

    Science.gov (United States)

    Sett, Riya; Ganguly, Aniruddha; Guchhait, Nikhil

    2016-11-01

    The present work demonstrates a detailed photophysics of bio-active drug-like acid viz., 2-hydroxynicotinic acid (2-HNA) and its interaction with a model plasma protein Bovine Serum Albumin (BSA). The drug which is in essence a vitamin-B3 derivative, is capable of exhibiting ultrafast lactim-lactam cross-over response and thereby the modulation of the lactam emission within the bio-environment of the protein has been depicted spectroscopically to reveal the drug-protein interaction. Apart from evaluating the binding constant, the probable location of the neutral drug molecule within the protein cavity (hydrophobic subdomain IIIA) has been explored by AutoDock-based blind docking simulation technique. In this microheterogeneous medium, slow solvent reorientation time with respect to the emissive lifetime of the drug explicate the Red Edge Effect (REE). To complement the findings about the binding process, chaotrope-induced protein denaturation has also been inspected. The probe also illustrates a perceptible difference in rotational relaxation time in confined medium than in aqueous medium which strengthen our verdict. Unfolding of the protein in the presence of the drug molecule has been probed by the decrease of the α-helical content, obtained via circular dichroism (CD) spectroscopy, which is also supported by the gradual slaughter of the esterase activity of the protein in the presence of the drug molecule.

  19. Change of pregnancy-associated protein A,urinary transferrin, D-dimer in patients with hypertension in pregnancy%妊娠相关蛋白 A、尿转铁蛋白、D-二聚体在妊娠期高血压病患者中的变化

    Institute of Scientific and Technical Information of China (English)

    张丽岩; 刘艳庚; 颜媛

    2015-01-01

    Objective To observe the significance of pregnancy-associated protein A (PAPP-A ), urinary transferrin,D-dimer in patients with hypertension in pregnancy and their correlation.Methods The study enrolled 120 patients with pregnancy-induced hypertension syndrome as pregnancy-induced hypertension group,at the same period, 30 healthy pregnant women with a full-term pregnancy were selected as the normal pregnancy group and 20 non-pregnant healthy women were as the healthy control group.The levels of PAPP-A,urinary transferrin and D-dimer were observed in pregnancy-induced hypertension group,normal pregnancy group and healthy control group,their levels and disease severity were detected in pregnancy-induced hypertension group and their relationship was explored. Results The levels of PAPP-A,urinary transferrin and D-dimer in pregnancy-induced hypertension group were significantly higher than those of normal pregnancy group and healthy control group (P < 0.01 ),and the levels in normal pregnancy group were also higher compared with those of healthy control group (P <0.01),as the severity of pregnancy-induced hypertension increased,the levels of PAPP-A,urinary transferrin and D-dimer increased (P <0.01).There were positive correlation between PAPP-A and urinary transferrin (r =0.593,P <0.01)or D-dimer (r=0.692,P <0.01),while there were positive correlation between D-dimer and urinary transferrin (r =0.622,P <0.01).Conclusion There are of great significances between the severity of pregnancy-induced hypertension and levels of PAPP-A,urinary transferrin,D-dimmer,and the items can be provided for the early diagnosis and treatment of pregnancy-induced hypertension.%目的:观察妊娠相关蛋白 A(PAPP-A)、尿转铁蛋白、D-二聚体在妊娠期高血压疾病患者检测中的意义及其相关性分析。方法选择在我院就诊的妊娠期高血压疾病患者120例,为妊娠期高血压疾病组,选择同期足月妊娠的健康孕妇30例,为正常妊娠组,选

  20. Improved first-trimester Down syndrome screening performance by lowering the false-positive rate: a prospective study of 9941 low-risk women

    DEFF Research Database (Denmark)

    Wøjdemann, K R; Shalmi, A C; Christiansen, M

    2005-01-01

    OBJECTIVE: To determine the performance of screening for Down syndrome (DS) and other major chromosomal abnormalities using nuchal translucency (NT), free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A) in a prospective study of a non...

  1. First-trimester combined screening for Down syndrome

    DEFF Research Database (Denmark)

    Pihl, Kasper; Sørensen, Tina Lindvig; Nørgaard Pedersen, Bent

    2008-01-01

    OBJECTIVE: To establish the relationship between the first-trimester screening markers [pregnancy-associated plasma protein A (PAPP-A), free human chorionic gonadotrophin-beta (beta-hCG), nuchal translucency (NT)], the Down syndrome (DS) risk estimate, and the adverse outcomes such as low birth...

  2. Impact of type 1 diabetes and glycemic control on fetal aneuploidy biochemical markers

    DEFF Research Database (Denmark)

    Madsen, Helen Nordahl; Ekelund, Charlotte Kvist; Tørring, Niels;

    2012-01-01

    Objective: To determine the influence of type 1 diabetes mellitus (T1DM) on the first trimester serum markers of fetal aneuploidy; pregnancy-associated plasma protein-A (PAPP-A) and free beta subunit of human chorionic gonadotropin (free β-hCG) and to evaluate the influence of glycemic control on...

  3. "辅助生殖导致孕妇血清中妊娠相关血浆蛋白-A水平降低并导致唐氏综合征妊娠早期筛查中假阳率升高"点评

    Institute of Scientific and Technical Information of China (English)

    相玉倩

    2010-01-01

    @@ 1论文题目及原文摘要 Pregnancies conceived using assisted reproductive technologies(ART)have low levels of pregnancy-associated plasma protein-A(PAPP-A) leading to a high rate of false-positive results in first trimester screening for Down syndrome

  4. Lipocalin-type prostaglandin D synthase is not a biomarker of atherosclerotic manifestations

    DEFF Research Database (Denmark)

    Hosbond, Susanne E; Diederichsen, Axel C P; Pedersen, Lise

    2014-01-01

    OBJECTIVE: Over the last decades Lipocalin-type prostaglandin D synthase (L-PGDS), Osteoprotegerin (OPG), Osteopontin (OPN) and Pregnancy associated plasma protein A (PAPP-A) have been reported to be associated with coronary artery disease, and L-PGDS has been proposed as a potential new diagnostic...

  5. Cribado de aneuploidias de primer trimestre en las gestaciones gemelares

    OpenAIRE

    Prats Rodríguez, Pilar

    2013-01-01

    Esta tesis está basada en dos artículos: Articulo 1: Early first-trimester free-β-hCG and PAPP-A serum distributions in monochorionic and dichorionic twins Objetivo: Examinar la distritución en primer trimestre de los marcadores bioquímicos de aneuploidias en gestaciones gemelares dependiendo de su corionicidad. Métodos: La free-β-human chorionic gonadotropin (hCG) en sangre materna y la pregnancy-associated plasma protein A (PAPP-A) fueron analizadas entre las semanas 8–13 + de ...

  6. Combination of Prenatal Screening of Pregnancy Associated Plasma Protein A with the Inter-fluorescence in Situ Hybridization for Prenatal Diagnosis of Down Syndrome%产前行妊娠相关血浆蛋白A筛查联合FISH诊断Down综合征

    Institute of Scientific and Technical Information of China (English)

    叶兹礼; 李文典; 吴玉萍

    2003-01-01

    目的:应用单项妊娠相关血浆蛋白A(PAPP-A)筛查与羊水间期荧光原位杂交(FISH)产前诊断相结合预防妊娠Down综合征胎儿.方法:采用酶联免疫方法(ELISA)对孕周分别为6~27周的1839例孕妇进行母血PAPP-A单项筛查,以低于同一孕周的中位数时视为可能妊娠Down综合征胎儿的高风险孕妇.取高风险孕妇羊水细胞直接进行间期FISH产前诊断并同时用部分羊水细胞遗传学检查作对照.结果:检出1例孕7周孕妇其PAPP-A值为0.051 U/L,低于同一孕周中位数20多倍.羊水细胞间期FISH结果显示,含5个杂交信号的核占所有杂交核的38.5%,与细胞遗传学分析的21三体核型完全一致.结论:单项PAPP-A筛查与羊水间期细胞FISH相结合是早期防治妊娠Down 综合征有效可行的方法.

  7. The relevance between carotid atherosclerosis and serum pregnancy-associated protein A of unstable angina patients%不稳定型心绞痛患者血清妊娠相关蛋白A与颈动脉粥样硬化的相关性

    Institute of Scientific and Technical Information of China (English)

    刘克坚; 罗春生; 邱强; 刘诚; 唐斌

    2012-01-01

    目的 探讨颈动脉粥样硬化、血清妊娠相关性蛋白A与不稳定型心绞痛、稳定型心绞痛、非冠心病的相关性.方法 因胸痛入院的患者1 w内行冠脉造影,排除急性及亚急性心梗后,不稳定型心绞痛、稳定型心绞痛、非冠心病各40例被纳入研究中,进行冠状动脉Gensini评分;彩超检测颈动脉内中膜厚度、斑块形成情况,应用酶联免疫吸附法测定血清妊娠相关蛋白A水平,并进行统计学分析.结果 除吸烟史外,各组间其余基线资料匹配;不稳定型心绞痛、稳定型心绞痛的冠脉Gensini评分、颈动脉粥样硬化指标均较非冠心病高(P<0.001);不稳定型心绞痛组比稳定型心绞痛及非冠心病组血清妊娠相关蛋白A的浓度高(P<0.001),妊娠相关蛋白A在不稳定型心绞痛患者明显升高,其与颈动脉粥样硬化指标、冠脉Gensini积分正相关;Grouse积分预测心绞痛型冠心病,敏感度、特异度分别为0.79、0.92;颈动脉内中膜厚度平均值预测心绞痛型冠心病敏感度、特异度分别为0.97、0.85;妊娠相关蛋白A预测不稳定型心绞痛敏感度、特异度分别为0.825、0.937.结论 颈动脉粥样硬化指标与冠状动脉Gensini积分有较好的相关性,而妊娠相关蛋白A可作为预测不稳定型心绞痛的指标;二者联合检测可能是预测不稳定型心绞痛的重要临床依据.%Objective To investigate the relevance between carotid atherosclerosis, serum pregnancy-associated protein A ( PAPP-A) and the incidence of unstable angina (UAP) , stable angina pectoris(SAP) , Non-coronary heart disease ( NCHD) ,to further discuss joint significance of carotid atherosclerosis and PAPP-A concentration in the forecast of UAP. Methods Patients admitted to hospital because of chest pain,coronary angiography were completed within 1 w, which with acute and subacute myocardial infarction had been excluded, then, 40 case of UAP,40 cases of SAP,40 cases of

  8. The relationship of carotid atherosclerosis,serum pregnancy-associated protein A and unstable angina%颈动脉粥样硬化、血清妊娠相关蛋白A与不稳定型心绞痛的相关性

    Institute of Scientific and Technical Information of China (English)

    罗春生; 邱强; 刘克坚; 严治涛; 罗丽萍; 周康; 刘诚

    2012-01-01

    Objective This study aimed to investigate the relationship of carotid atherosclerosis, serum pregnancy - associated protein A ( PAPP - A ), unstable angina ( LAP ), stable angina pectoris( SAP ), and non - coronary heart disease ( NCIID ), and discuss the joint significance of carotid atherosclerosis and PAPP - A concentration in the prediction of LAP. Methods Patients were admitted to hospital because of chest pain. Coronary angiography was completed within 1 week. After exclusion of the diagnosis of acute and subacute myocardial infarction, patients with LAP ( n - 40 ), SAP ( n = 40 ), and NCIID ( n - 40 ) were taken into the research. Gensini score, intima - media thickness( IMT )of carotid artery , plaque formation of carotid artery were determined by color doppler ultrasound, serum level of PAPP - A was determined by enzyme -linked immunosorbent assay ( EL1SA ). The results were analyzed statistically. Results Except smoking history, baseline information of the groups matched each other. Coronary Gensini score and indicators of carotid atherosclerosis of LAP and SAP were higher than NIICD ( P < 0. 001 ). Serum concentration of PAPP - A of LAP was higher than SAP and MIICD ( P < 0. 001 ). PAPP - A in patients with LAP was significantly higher, and its concentration was positively correlated with indicators of carotid atherosclerosis and coronary artery Gensini score. For the prediction of angina - type CUD, the sensitivity and specificity of Crouse score were respectively 0. 79 and 0. 92, these values of the average of carotid 1MT were respectively 0. 97 and 0. 85. For the prediction of LAP, the sensitivity and specificity of PAPP - A were respectively 0. 825 and 0. 937. Conclusion Indicators of carotid atherosclerosis and coronary artery Gensini score are well correlated, and PAPP - A can be served as a predictable indicator of LAP. The combined use of these parameters may provide important clinical basis for the prediction of LAP.%目的 探讨颈动脉粥

  9. Second trimester two-step trisomy 18 screening using maternal serum markers.

    Science.gov (United States)

    Muller, Françoise; Sault, Corinne; Lemay, Catherine; Roussel-Mizon, Nathalie; Forestier, François; Frendo, Jean-Louis

    2002-07-01

    Trisomy 21 maternal serum marker screening has led to screening for other anomalies, including trisomy 18. Trisomy 18 is generally prenatally diagnosed because of major morphological defects. However, in up to 30% of cases ultrasound signs are unclear, and in most cases diagnosis is performed late in pregnancy. Of the different maternal serum markers, PAPP-A is now considered as the best for trisomy 18 screening. However, pregnancy-associated plasma protein A (PAPP-A) is of value in first trimester screening for trisomy 21, but not in the second trimester. We therefore propose a two-step screening strategy. Based on 45 trisomy 18 cases, we confirm the values of alpha-fetoprotein (AFP) (median 0.61 MoM), free beta-human chorionic gonadotrophin (beta-hCG) (median 0.24 MoM) and of PAPP-A (median 0.08 MoM). In the first step, a 0.5 MoM cut-off for AFP or for free beta-hCG resulted in detection of 37/45 trisomy 18 cases (82%) with a 10% false-positive rate. The second step consisted of the measurement of PAPP-A for all these false-positive cases. Using a PAPP-A cut-off of 0.5 MoM, all the 37 trisomy 18 cases were detected, but now with a 0.1-0.2% false-positive rate. Amniocentesis was only offered to these few patients. This two-step second trimester screening will be of value for patients who have not been included in first trimester screening based on nuchal translucency (NT) measurement combined with the first trimester markers, PAPP-A and free beta-hCG. Copyright 2002 John Wiley & Sons, Ltd.

  10. Pregnancy Specific Glycoprotein 17 Binds to the Extracellular Loop 2 of Its Receptor, CD9, and Induces the Secretion of IL-10, IL-6, PGE2, and TGFBeta1 in Murine Macrophages

    Science.gov (United States)

    2004-01-01

    deficiency of placental IL-10 in preeclampsia . J Immunol, 1999. 163(6): p. 3491-5. 53. Raghupathy, R., et al., Maternal Th1- and Th2-type reactivity to...such as progesterone regulate the immune response at locations far from its original site of production but its use for the management of autoimmune...M.S. Wilson, Value of Schwangerschaftsprotein 1 (SP1) and pregnancy-associated plasma protein-A (PAPP-A) in the clinical management of threatened

  11. Normative weight-adjusted models for the median levels of first trimester serum biomarkers for trisomy 21 screening in a specific ethnicity.

    Science.gov (United States)

    Kor-Anantakul, Ounjai; Suntharasaj, Thitima; Suwanrath, Chitkasaem; Hanprasertpong, Tharangrut; Pranpanus, Savitree; Pruksanusak, Ninlapa; Janwadee, Suthiraporn; Geater, Alan

    2017-01-01

    To establish normative weight-adjusted models for the median levels of first trimester serum biomarkers for trisomy 21 screening in southern Thai women, and to compare these reference levels with Caucasian-specific and northern Thai models. A cross-sectional study was conducted in 1,150 normal singleton pregnancy women to determine serum pregnancy-associated plasma protein-A (PAPP-A) and free β-human chorionic gonadotropin (β-hCG) concentrations in women from southern Thailand. The predicted median values were compared with published equations for Caucasians and northern Thai women. The best-fitting regression equations for the expected median serum levels of PAPP-A (mIU/L) and free β- hCG (ng/mL) according to maternal weight (Wt in kg) and gestational age (GA in days) were: [Formula: see text] and [Formula: see text] Both equations were selected with a statistically significant contribution (p< 0.05). Compared with the Caucasian model, the median values of PAPP-A were higher and the median values of free β-hCG were lower in the southern Thai women. And compared with the northern Thai models, the median values of both biomarkers were lower in southern Thai women. The study has successfully developed maternal-weight- and gestational-age-adjusted median normative models to convert the PAPP-A and free β-hCG levels into their Multiple of Median equivalents in southern Thai women. These models confirmed ethnic differences.

  12. Medians and correction factors for biochemical and ultrasound markers in Chinese women undergoing first-trimester screening for trisomy 21.

    Science.gov (United States)

    Sahota, D S; Leung, T Y; Fung, T Y; Chan, L W; Law, L W; Lau, T K

    2009-04-01

    To establish normative values and distribution parameters of first-trimester maternal serum free beta-human chorionic gonadotropin (beta-hCG), pregnancy-associated plasma protein-A (PAPP-A) and fetal nuchal translucency (NT) thickness in Chinese women and to examine the effects of covariates on their levels. Maternal serum free beta-hCG, PAPP-A and fetal NT were measured in 9762 women presenting for first-trimester combined screening for Down syndrome at 11 to 14 weeks of gestation. Individuals' markers were converted to multiples of the median (MoM) using expected medians estimated by performing a weighted regression analysis. Multivariate regression analysis was performed to assess the influence of maternal weight, parity, ethnicity, chorionicity in twin pregnancies, smoking, insulin-dependent diabetes and mode of conception on individual marker MoM levels. Both free beta-hCG and PAPP-A median values demonstrated an exponential relationship with gestational age in days. Multivariate regression analysis indicated that free beta-hCG MoM was statistically significantly dependent on maternal weight (P hCG and PAPP-A to their MoM equivalents and correction factors have been determined to adjust for maternal and pregnancy characteristics for use in ethnic Chinese women undergoing first-trimester screening for aneuploidy. (c) 2009 ISUOG. Published by John Wiley & Sons, Ltd.

  13. First-trimester screening for trisomies 21, 18 and 13 by ultrasound and biochemical testing.

    Science.gov (United States)

    Wright, D; Syngelaki, A; Bradbury, I; Akolekar, R; Nicolaides, K H

    2014-01-01

    To examine the performance of screening for trisomies 21, 18 and 13 at 11-13 weeks' gestation using specific algorithms for these trisomies based on combinations of fetal nuchal translucency thickness (NT), fetal heart rate (FHR), ductus venosus pulsatility index for veins (DV PIV), and serum free β-human chorionic gonadotropin (β-hCG), pregnancy-associated plasma protein A (PAPP-A), placental growth factor (PLGF) and α-fetoprotein (AFP). Model-based estimates of screening performance were produced for the distribution of maternal ages in England and Wales in 2011, and prospectively collected data on fetal NT, FHR, DV PIV, β-hCG, PAPP-A, PLGF and AFP from singleton pregnancies undergoing aneuploidy screening. In screening by NT, FHR, free β-hCG and PAPP-A, using specific algorithms for trisomy 21 and trisomies 18 and 13 at the risk cutoff of 1:100, the estimated detection rate (DR) was 87.0% for trisomy 21 and 91.8% for trisomies 18 and 13, at a false-positive rate (FPR) of 2.2%. Addition of PLGF, AFP and DV PIV increased the DR to 93.3% for trisomy 21 and 95.4% for trisomies 18 and 13 and reduced the FPR to 1.3%. Effective screening for trisomies can be achieved using specific algorithms based on NT, FHR, DV PIV, β-hCG, PAPP-A, PLGF and AFP. © 2013 S. Karger AG, Basel.

  14. Fibronectin binding to protein A-containing staphylococci.

    OpenAIRE

    Doran, J E; Raynor, R H

    1981-01-01

    Fibronectin (Fn) was found to bind to protein A-containing isolates of Staphylococcus aureus, but not to mutant strains devoid of this protein nor to clinical isolates of S. epidermidis. Fn was purified from human plasma by affinity chromatography on gelatin-Sepharose. After elution with 4 M urea, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of purified material detected no immunoglobulin contamination. This purified Fn was radiolabeled with 125I and used in binding assays. Quant...

  15. Plasma turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Horton, W. [Univ. of Texas, Austin, TX (United States). Inst. for Fusion Studies; Hu, G. [Globalstar LP, San Jose, CA (United States)

    1998-07-01

    The origin of plasma turbulence from currents and spatial gradients in plasmas is described and shown to lead to the dominant transport mechanism in many plasma regimes. A wide variety of turbulent transport mechanism exists in plasmas. In this survey the authors summarize some of the universally observed plasma transport rates.

  16. Application value of serum pregnancy-asscociated plasma protein A in primiparous women of gestational diabetes mellitus%妊娠相关血浆蛋白A在初产妇妊娠期糖尿病中的应用价值

    Institute of Scientific and Technical Information of China (English)

    韦僖雯; 李凯; 谭汝宏; 陈淑芬; 李相新

    2016-01-01

    Objective To assess the correlation between the pregnancy‐associated plasma protein A (PAPP‐A)level with gesta‐tional diabetes mellitus(GDM )in primiparous women .Methods The nonparametric test and Logistic regression analysis were used to retrospectively analyze 168 pregnant women of GDM and 273 normal pregnant women ,including age ,body weight ,PAPP‐A ,freeβ‐human chorionic gonadotropin(fβ‐hCG) .Results The age had significant difference between GDM group and control group(P<0 .01) ,the PAPP‐A concentration and corrected multiple of the median (MoM )of PAPP‐A in the GDM group were significantly lower than those in the control group(P<0 .01) .Conclusion Low level of PAPP‐A during early pregnant stage in primiparas is strongly associated with GDM and can be used as the risk factor of GDM .%目的:探讨初产妇孕早期血清中的妊娠相关血浆蛋白 A (PAPP‐A )水平与妊娠期糖尿病(GDM )发生的关系。方法用非参数检验及Logistic回归分析对168例GDM孕妇及273例健康孕妇的年龄、体质量、PAPP‐A、游离β人绒毛膜促性腺激素(fβ‐HCG)水平进行回顾性分析。结果 GDM 组年龄与对照组差异有统计学意义(P<0.01),PAPP‐A浓度及 PAPP‐A MoM均明显低于对照组,差异有统计学意义(P<0.01)。结论初产妇孕早期低水平PAPP‐A与GDM 强相关,并可作为GDM的危险因素。

  17. Plasma harmonics

    CERN Document Server

    Ganeev, Rashid A

    2014-01-01

    Preface; Why plasma harmonics? A very brief introduction Early stage of plasma harmonic studies - hopes and frustrations New developments in plasma harmonics studies: first successes Improvements of plasma harmonics; Theoretical basics of plasma harmonics; Basics of HHG Harmonic generation in fullerenes using few-cycle pulsesVarious approaches for description of observed peculiarities of resonant enhancement of a single harmonic in laser plasmaTwo-colour pump resonance-induced enhancement of odd and even harmonics from a tin plasmaCalculations of single harmonic generation from Mn plasma;Low-o

  18. First-trimester risk calculation for trisomy 13, 18, and 21: comparison of the screening efficiency between 2 locally developed programs and commercial software

    DEFF Research Database (Denmark)

    Sørensen, Steen; Momsen, Günther; Sundberg, Karin

    2011-01-01

    Reliable individual risk calculation for trisomy (T) 13, 18, and 21 in first-trimester screening depends on good estimates of the medians for fetal nuchal translucency thickness (NT), free β-subunit of human chorionic gonadotropin (hCGβ), and pregnancy-associated plasma protein-A (PAPP-A) in mate......Reliable individual risk calculation for trisomy (T) 13, 18, and 21 in first-trimester screening depends on good estimates of the medians for fetal nuchal translucency thickness (NT), free β-subunit of human chorionic gonadotropin (hCGβ), and pregnancy-associated plasma protein-A (PAPP...

  19. First-trimester risk calculation for trisomy 13, 18, and 21: comparison of the screening efficiency between 2 locally developed programs and commercial software

    DEFF Research Database (Denmark)

    Sørensen, Steen; Momsen, Günther; Sundberg, Karin

    2011-01-01

    Reliable individual risk calculation for trisomy (T) 13, 18, and 21 in first-trimester screening depends on good estimates of the medians for fetal nuchal translucency thickness (NT), free ß-subunit of human chorionic gonadotropin (hCGß), and pregnancy-associated plasma protein-A (PAPP-A) in mate......Reliable individual risk calculation for trisomy (T) 13, 18, and 21 in first-trimester screening depends on good estimates of the medians for fetal nuchal translucency thickness (NT), free ß-subunit of human chorionic gonadotropin (hCGß), and pregnancy-associated plasma protein-A (PAPP...

  20. First-trimester combined screening for trisomy 21 at 7-14 weeks' gestation.

    Science.gov (United States)

    Wright, D; Spencer, K; Kagan K, K; Tørring, N; Petersen, O B; Christou, A; Kallikas, J; Nicolaides, K H

    2010-10-01

    To establish an algorithm for first-trimester combined screening for trisomy 21 with biochemical testing from 7 to 14 weeks' gestation and ultrasound testing at 11-13 weeks. This was a multicenter study of 886 pregnancies with trisomy 21 and 222 475 unaffected pregnancies with measurements of free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 7-14 weeks' gestation. Multiple regression modeling of log-transformed marker values was used to produce log multiples of the median (MoM) values for PAPP-A and free β-hCG. The models included terms for the center attended and the machine used for biochemical analysis, gestational age, maternal racial origin, maternal weight, smoking status and method of conception. Bivariate Gaussian distributions were fitted to log MoM PAPP-A and log MoM free β-hCG in trisomy 21 and in unaffected pregnancies. In each case the patient-specific risk for trisomy 21 was estimated by multiplying the individual maternal age-related risk with the likelihood ratio (LR) for fetal nuchal translucency (NT) according to the mixture model and the combined LR for maternal serum free β-hCG and PAPP-A. Estimates of detection rates for trisomy 21 and false-positive rates were calculated for combined screening with measurements of NT at 12 weeks together with measurements of free β-hCG and PAPP-A from 8 to 13 weeks. In trisomy 21 pregnancies the mean log MoM free β-hCG increased linearly with gestation between 7 and 14 weeks, whereas the relation between log MoM PAPP-A and gestation was fitted by a quadratic equation such that the maximum separation between trisomy 21 and unaffected pregnancies occurs at 9-10 weeks. At a false-positive rate of 3% the detection rate of combined screening at 12 weeks was 86% and this increased to 90% by biochemical testing at 9 weeks and ultrasound scanning at 12 weeks. The detection rate increased to 92% by measuring PAPP-A at 9 weeks and free β-hCG at the time of the scan

  1. Dusty plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Fortov, Vladimir E; Khrapak, Aleksei G; Molotkov, Vladimir I; Petrov, Oleg F [Institute for High Energy Densities, Associated Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation); Khrapak, Sergei A [Max-Planck-Institut fur Extraterrestrische Physik, Garching (Germany)

    2004-05-31

    The properties of dusty plasmas - low-temperature plasmas containing charged macroparticles - are considered. The most important elementary processes in dusty plasmas and the forces acting on dust particles are investigated. The results of experimental and theoretical investigations of different states of strongly nonideal dusty plasmas - crystal-like, liquid-like, gas-like - are summarized. Waves and oscillations in dusty plasmas, as well as their damping and instability mechanisms, are studied. Some results on dusty plasma investigated under microgravity conditions are presented. New directions of experimental research and potential applications of dusty plasmas are discussed. (reviews of topical problems)

  2. Early Biochemical Screening for Fetal Aneuploidy in the First Trimester

    DEFF Research Database (Denmark)

    Tørring, Niels

    2013-01-01

    Background Screening for fetal trisomy 21 in the first trimester includes analysis of the serological markers pregnancy-associated plasma protein A (PAPP-A) and free beta human choriogonadotropin (free βhCG). With the recent launch of the PAPP-A free βhCG and assays on the Roche Cobas and Elecsys...... platforms, we investigated their clinical and analytical performance in samples from gestaional weeks 8+0 to 14+0. Methods. We conducted a multicenter study based on serum samples from 5397 pregnancies including 107 samples from cases of verified fetal trisomy 21 at 8 to 14 weeks of gestation. A technical...... with the standards for biochemical assays for prenatal screening set by the Fetal Medicine Foundation, with low assay imprecision, and a high clinical performance of prenatal screening for fetal trisomy in the first trimester....

  3. Plasma waves

    CERN Document Server

    Swanson, DG

    1989-01-01

    Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th

  4. Plasma astrophysics

    CERN Document Server

    Kaplan, S A; ter Haar, D

    2013-01-01

    Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

  5. Identification of fibrin clot-bound plasma proteins

    NARCIS (Netherlands)

    S. Talens (Simone); F.W.G. Leebeek (Frank); J.A.A. Demmers (Jeroen); D.C. Rijken (Dingeman)

    2012-01-01

    textabstractSeveral proteins are known to bind to a fibrin network and to change clot properties or function. In this study we aimed to get an overview of fibrin clot-bound plasma proteins. A plasma clot was formed by adding thrombin, CaCl2 and aprotinin to citrated platelet-poor plasma and unbound

  6. Plasma Antenna

    OpenAIRE

    N M Vijay

    2014-01-01

    The fundamental base of plasma antenna is the use of an ionized medium as a conductor. The plasma antenna is a radiofrequency antenna formed by a plasma columns, Filaments or sheets, which are excited by a surface wave. The relevance of this device is how rapidly it can be turned on and off, only applying an electrical pulse. Besides its wide carrier frequency, the great directivity and controllable antenna shape. Otherwise a disadvantage is that it needs energy to be ionized....

  7. Plasma physics

    CERN Document Server

    Drummond, James E

    2013-01-01

    A historic snapshot of the field of plasma physics, this fifty-year-old volume offers an edited collection of papers by pioneering experts in the field. In addition to assisting students in their understanding of the foundations of classical plasma physics, it provides a source of historic context for modern physicists. Highly successful upon its initial publication, this book was the standard text on plasma physics throughout the 1960s and 70s.Hailed by Science magazine as a ""well executed venture,"" the three-part treatment ranges from basic plasma theory to magnetohydrodynamics and microwa

  8. First trimester maternal serum placenta growth factor (PIGF)concentrations in pregnancies with fetal trisomy 21 or trisomy 18.

    Science.gov (United States)

    Spencer, K; Liao, A W; Ong, C Y; Geerts, L; Nicolaides, K H

    2001-09-01

    Placenta growth factor (PIGF), an angiogenic factor belonging to the vascular endothelial growth factor family, pregnancy-associated plasma protein A (PAPP-A) and free beta-human chorionic gonadotrophin (beta-hCG) were measured in maternal serum from 45 pregnancies with trisomy 21, 45 with trisomy 18 and 493 normal controls at 10-13 completed weeks of gestation. In the normal pregnancies maternal serum PIGF levels increased exponentially with gestation. The median multiple of the median (MoM) PIGF concentration in the trisomy 21 group (1.26 MoM) was significantly higher (ptrisomy 18 group the median PIGF was lower (0.889 MoM) but this did not quite reach significance (p=0.064). The corresponding median MoM values for PAPP-A were 1.00 MoM for the controls, 0.49 MoM for trisomy 21 and 0.16 MoM for trisomy 18. The median MoM values for free beta-hCG were 1.00 MoM for the controls, 2.05 MoM for trisomy 21 and 0.38 MoM for trisomy 18. In the control group there was a small but significant correlation of PIGF with free beta-hCG (r=+0.1024) and PAPP-A (r=+0.2288). In the trisomy 18 group there was a significant association between PIGF and free beta-hCG (r=+0.2629) but not with PAPP-A (r=+0.0038). In the trisomy 21 group there was a small but significant association with PAPP-A (r=+0.1028) but not with free beta-hCG (r=+0.0339). The separation of affected and unaffected pregnancies in maternal serum PIGF is small, and therefore it is unlikely that measurement of PIGF would improve screening for these abnormalities provided by the combination of fetal nuchal translucency and maternal serum PAPP-A and free beta-hCG. Copyright 2001 John Wiley & Sons, Ltd.

  9. Early Prognostic Factors for the Progress of Preeclampsia – Our Experience in the Period 2010-2011

    Directory of Open Access Journals (Sweden)

    Mariya Angelova Angelova

    2016-08-01

    Full Text Available AIM: To determine the prognostic value of the low Pregnancy-associated plasma protein A (PAPP-A levels in the early stages of pregnancy (11–13 weeks GA independently and in combination with a Doppler test of the uterine arteries during the second half of pregnancy (22–23 weeks GA. MATERIAL AND METHODS: The study covered the period 2010–2011 and included 106 pregnant women, aged 35–40, with a single child pregnancy. The research excluded pregnant women with anomalies of the fetus, smokers and women taking prophylactically low doses of aspirin. RESULTS: Thirty-six pregnant women had PAPP-A level below 0.4 MoM, whereas 20 of them developed preeclampsia and 7 – early preeclampsia. The combination of the low PAPP-A values and the abnormal Doppler test of the uterine arteries is with a considerably better prognostic value in regards to the risk of developing preeclampsia. CONCLUSION: The Doppler test is a non-invasive, quick and easy method for assessment of the uterine-placental blood flow.

  10. First trimester predictors of adverse pregnancy outcomes.

    Science.gov (United States)

    Brameld, Kate J; Dickinson, Jan E; O'Leary, Peter; Bower, Carol; Goldblatt, Jack; Hewitt, Beverley; Murch, Ashleigh; Stock, Rosanne

    2008-12-01

    To identify first trimester indicators of adverse pregnancy outcomes. Data were obtained from the statewide evaluation of first trimester screening for Down syndrome in Western Australia which included 22,695 pregnancies screened between August 2001 and October 2003. Screening data were linked with pregnancy outcome information from the Hospital Morbidity Database and the Birth Defects Registry. The odds ratios (OR) of adverse outcomes were analysed for combined risk incorporating maternal age, nuchal translucency (NT) and biochemical parameters and then separately for each parameter (pregnancy-associated plasma protein-A (PAPP-A), free beta human chorionic gonadotropin (beta-hCG) and NT). Risk assessments for first trimester combined screening are derived from maternal age, ultrasound measurement of fetal NT, maternal serum free beta-hCG and PAPP-A. Increased combined risk for Down syndrome was significantly (P beta-hCG and increased NT were less consistently associated with adverse outcomes and high levels of free beta-hCG showed limited use as an indicator. The detection rates for all outcomes other than Down syndrome were less than 40%. Biochemical indicators and NT that are measured during first trimester screening for Down syndrome show a number of associations with adverse outcomes, but do not show appropriate performance characteristics for screening tests. These data are consistent with the view that the individual components, specifically low PAPP-A levels alone, do not provide an effective screening tool for adverse pregnancy outcomes.

  11. The significance of fetal maxillary length in the first trimester screening for trisomy 21.

    Science.gov (United States)

    Unsal, Naim; Ozat, Mustafa; Kanat-Pektas, Mine; Gungor, Tayfun; Danisman, Nuri

    2011-06-01

    The present study aims to specify the significance of fetal maxillary length by establishing a nomogram for a Turkish population and by investigating its relationship with the ultrasonographic and biochemical parameters which are commonly used to screen trisomy 21 in the first trimester of pregnancy. The present observational study investigates 1,308 Turkish women who had 11- to 14-week-old singleton healthy pregnancies. Fetal crown-rump length (CRL), nuchal translucency (NT), nasal bone length (NBL) and maxillary length are measured by ultrasonography and maternal serum concentrations of pregnancy-associated plasma protein-A (PAPP-A) and free beta-human chorionic gonadotropin (HCG) are determined. A positive and significant correlation was detected between the fetal maxillary length and gestational age (r = 0.309, P HCG (r = -0.238, P trisomy 21 in first trimester. Fetal maxillary length is also found to correlate with gestational age, CRL, NBL and PAPP-A significantly. It would be rational to use a combination of nasal and maxillary bone length measurements in case serum concentrations of PAPP-A or beta-HCG cannot be assessed.

  12. Comparison of Different Blood Collection, Sample Matrix, and Immunoassay Methods in a Prenatal Screening Setting

    Directory of Open Access Journals (Sweden)

    Jeroen L. A. Pennings

    2014-01-01

    Full Text Available We compared how measurements of pregnancy-associated plasma protein A (PAPP-A and the free beta subunit of human chorionic gonadotropin (fβ-hCG in maternal blood are influenced by different methods for blood collection, sample matrix, and immunoassay platform. Serum and dried blood spots (DBS were obtained by venipuncture and by finger prick of 19 pregnant women. PAPP-A and fβ-hCG from serum and from DBS were measured by conventional indirect immunoassay on an AutoDELFIA platform and by antibody microarray. We compared methods based on the recoveries for both markers as well as marker levels correlations across samples. All method comparisons showed high correlations for both marker concentrations. Recovery levels of PAPP-A from DBS were 30% lower, while those of fβ-hCG from DBS were 50% higher compared to conventional venipuncture serum. The recoveries were not affected by blood collection or immunoassay method. The high correlation coefficients for both markers indicate that DBS from finger prick can be used reliably in a prenatal screening setting, as a less costly and minimally invasive alternative for venipuncture serum, with great logistical advantages. Additionally, the use of antibody arrays will allow for extending the number of first trimester screening markers on maternal and fetal health.

  13. Plasma chromograninx

    DEFF Research Database (Denmark)

    Goetze, Jens P; Hilsted, Linda M; Rehfeld, Jens F

    2014-01-01

    Cardiovascular risk assessment remains difficult in elderly patients. We examined whether chromogranin A (CgA) measurement in plasma may be valuable in assessing risk of death in elderly patients with symptoms of heart failure in a primary care setting. A total of 470 patients (mean age 73 years......) were followed for 10 years. For CgA plasma measurement, we used a two-step method including a screening test and a confirmative test with plasma pre-treatment with trypsin. Cox multivariable proportional regression and receiver-operating curve (ROC) analyses were used to assess mortality risk...... of follow-up showed significant additive value of CgA confirm measurements compared with NT-proBNP and clinical variables. CgA measurement in the plasma of elderly patients with symptoms of heart failure can identify those at increased risk of short- and long-term mortality....

  14. Plasma Cleaning

    Science.gov (United States)

    Hintze, Paul E.

    2016-01-01

    NASA's Kennedy Space Center has developed two solvent-free precision cleaning techniques: plasma cleaning and supercritical carbon dioxide (SCCO2), that has equal performance, cost parity, and no environmental liability, as compared to existing solvent cleaning methods.

  15. Plasma confinement

    CERN Document Server

    Hazeltine, R D

    2003-01-01

    Detailed and authoritative, this volume examines the essential physics underlying international research in magnetic confinement fusion. It offers readable, thorough accounts of the fundamental concepts behind methods of confining plasma at or near thermonuclear conditions. Designed for a one- or two-semester graduate-level course in plasma physics, it also represents a valuable reference for professional physicists in controlled fusion and related disciplines.

  16. Is maternal serum total hCG a marker of trisomy 21 in the first trimester of pregnancy?

    Science.gov (United States)

    Spencer, K; Berry, E; Crossley, J A; Aitken, D A; Nicolaides, K H

    2000-04-01

    In a study of 130 first trimester cases of trisomy 21 and 959 controls we have shown that the median MoM for alpha-fetoprotein (AFP) is lower (0.82) and that for total human chorionic gonadotrophin (hCG) is higher (1.31) than in the control group. For AFP 15.3% of cases were below the 5th centile and for total hCG 19. 8% were above the 95th centile. The median shift observed for AFP and total hCG is poorer than that for pregnancy associated plasma protein-A (PAPP-A) or free beta-hCG and together with maternal age, AFP and total hCG could only be expected to detect 40% of cases. In combination with PAPP-A, total hCG would identify 52% of cases, somewhat less than the 67% observed with free beta-hCG and PAPP-A. However, we have demonstrated for total hCG a significant temporal change in median MoM with gestational age. Before 70 days the median MoM was less than 0.5, between 70 and 83 days this increased to 1.13, and between 84 and 97 days this increased to 1.52. This median shift has significant implications for interpreting previous studies and even more significant implications for detection rates. When population parameters specific to the gestational age in question are used, detection rates with total hCG and PAPP-A increase from 47% at 70-83 days to 60% at 84-97 days. This observation explains much of the confusion around total hCG in the first trimester and shows the importance of selecting analyte pairs and population parameters appropriate to the time in gestation when screening is performed. Copyright 2000 John Wiley & Sons, Ltd.

  17. The Insulin-Like Growth Factor System in the Long-Lived Naked Mole-Rat

    Science.gov (United States)

    Brohus, Malene; Gorbunova, Vera; Faulkes, Chris G.; Overgaard, Michael T.; Conover, Cheryl A.

    2015-01-01

    Naked mole-rats (Heterocephalus glaber) (NMRs) are the longest living rodents known. They show negligible senescence, and are resistant to cancers and certain damaging effects associated with aging. The insulin-like growth factors (IGFs) have pluripotent actions, influencing growth processes in virtually every system of the body. They are established contributors to the aging process, confirmed by the demonstration that decreased IGF signaling results in life-extending effects in a variety of species. The IGFs are likewise involved in progression of cancers by mediating survival signals in malignant cells. This report presents a full characterization of the IGF system in the NMR: ligands, receptors, IGF binding proteins (IGFBPs), and IGFBP proteases. A particular emphasis was placed on the IGFBP protease, pregnancy-associated plasma protein-A (PAPP-A), shown to be an important lifespan modulator in mice. Comparisons of IGF-related genes in the NMR with human and murine sequences indicated no major differences in essential parts of the IGF system, including PAPP-A. The protease was shown to possess an intact active site despite the report of a contradictory genome sequence. Furthermore, PAPP-A was expressed and translated in NMRs cells and retained IGF-dependent proteolytic activity towards IGFBP-4 and IGF-independent activity towards IGFBP-5. However, experimental data suggest differential regulatory mechanisms for PAPP-A expression in NMRs than those described in humans and mice. This overall description of the IGF system in the NMR represents an initial step towards elucidating the complex molecular mechanisms underlying longevity, and how these animals have evolved to ensure a delayed and healthy aging process. PMID:26694858

  18. The Insulin-Like Growth Factor System in the Long-Lived Naked Mole-Rat.

    Directory of Open Access Journals (Sweden)

    Malene Brohus

    Full Text Available Naked mole-rats (Heterocephalus glaber (NMRs are the longest living rodents known. They show negligible senescence, and are resistant to cancers and certain damaging effects associated with aging. The insulin-like growth factors (IGFs have pluripotent actions, influencing growth processes in virtually every system of the body. They are established contributors to the aging process, confirmed by the demonstration that decreased IGF signaling results in life-extending effects in a variety of species. The IGFs are likewise involved in progression of cancers by mediating survival signals in malignant cells. This report presents a full characterization of the IGF system in the NMR: ligands, receptors, IGF binding proteins (IGFBPs, and IGFBP proteases. A particular emphasis was placed on the IGFBP protease, pregnancy-associated plasma protein-A (PAPP-A, shown to be an important lifespan modulator in mice. Comparisons of IGF-related genes in the NMR with human and murine sequences indicated no major differences in essential parts of the IGF system, including PAPP-A. The protease was shown to possess an intact active site despite the report of a contradictory genome sequence. Furthermore, PAPP-A was expressed and translated in NMRs cells and retained IGF-dependent proteolytic activity towards IGFBP-4 and IGF-independent activity towards IGFBP-5. However, experimental data suggest differential regulatory mechanisms for PAPP-A expression in NMRs than those described in humans and mice. This overall description of the IGF system in the NMR represents an initial step towards elucidating the complex molecular mechanisms underlying longevity, and how these animals have evolved to ensure a delayed and healthy aging process.

  19. plasma treatment

    Directory of Open Access Journals (Sweden)

    Puač Nevena

    2014-11-01

    Full Text Available In this paper we will present results for plasma sterilization of planktonic samples of two reference strains of bacteria, Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212. We have used a plasma needle as a source of non-equilibrium atmospheric plasma in all treatments. This device is already well characterized by OES, derivative probes and mass spectrometry. It was shown that power delivered to the plasma is bellow 2 W and that it produces the main radical oxygen and nitrogen species believed to be responsible for the sterilization process. Here we will only present results obtained by electron paramagnetic resonance which was used to detect the OH, H and NO species. Treatment time and power delivered to the plasma were found to have the strongest influence on sterilization. In all cases we have observed a reduction of several orders of magnitude in the concentration of bacteria and for the longest treatment time complete eradication. A more efficient sterilization was achieved in the case of gram negative bacteria.

  20. Plasma metallization

    CERN Document Server

    Crowther, J M

    1997-01-01

    Many methods are currently used for the production of thin metal films. However, all of these have drawbacks associated with them, for example the need for UHV conditions, high temperatures, exotic metal precursors, or the inability to coat complex shaped objects. Reduction of supported metal salts by non-isothermal plasma treatment does not suffer from these drawbacks. In order to produce and analyse metal films before they become contaminated, a plasma chamber which could be attached directly to a UHV chamber with XPS capability was designed and built. This allowed plasma treatment of supported metal salts and surface analysis by XPS to be performed without exposure of the metal film to the atmosphere. Non-equilibrium plasma treatment of Nylon 66 supported gold(lll) chloride using hydrogen as the feed gas resulted in a 95% pure gold film, the remaining 5% of the film being carbon. If argon or helium were used as the feed gases during plasma treatment the resultant gold films were 100% pure. Some degree of s...

  1. Plasma dynamo

    CERN Document Server

    Rincon, F; Schekochihin, A A; Valentini, F

    2015-01-01

    Magnetic fields pervade the entire Universe and, through their dynamical interactions with matter, affect the formation and evolution of astrophysical systems from cosmological to planetary scales. How primordial cosmological seed fields arose and were further amplified to $\\mu$Gauss levels reported in nearby galaxy clusters, near equipartition with kinetic energy of plasma motions and on scales of at least tens of kiloparsecs, is a major theoretical puzzle still largely unconstrained by observations. Extragalactic plasmas are weakly collisional (as opposed to collisional magnetohydrodynamic fluids), and whether magnetic-field growth and its sustainment through an efficient dynamo instability driven by chaotic motions is possible in such plasmas is not known. Fully kinetic numerical simulations of the Vlasov equation in a six-dimensional phase space necessary to answer this question have until recently remained beyond computational capabilities. Here, we show by means of such simulations that magnetic-field a...

  2. Plasma medicine

    CERN Document Server

    Fridman, Alexander

    2012-01-01

    This comprehensive text is suitable for researchers and graduate students of a 'hot' new topic in medical physics. Written by the world's leading experts,  this book aims to present recent developments in plasma medicine, both technological and scientific, reviewed in a fashion accessible to the highly interdisciplinary audience consisting of doctors, physicists, biologists, chemists and other scientists, university students and professors, engineers and medical practitioners. The book focuses on major topics and covers the physics required to develop novel plasma discharges relevant for medic

  3. Plasma physics and engineering

    CERN Document Server

    Fridman, Alexander

    2011-01-01

    Part I: Fundamentals of Plasma Physics and Plasma ChemistryPlasma in Nature, in the Laboratory, and in IndustryOccurrence of Plasma: Natural and Man MadeGas DischargesPlasma Applications, Plasmas in IndustryPlasma Applications for Environmental ControlPlasma Applications in Energy ConversionPlasma Application for Material ProcessingBreakthrough Plasma Applications in Modern TechnologyElementary Processes of Charged Species in PlasmaElementary Charged Particles in Plasma and Their Elastic and Inelastic CollisionsIonization ProcessesMechanisms of Electron Losses: The Electron-Ion RecombinationEl

  4. Photoaffinity Labeling of Plasma Proteins

    Directory of Open Access Journals (Sweden)

    Masaki Otagiri

    2013-11-01

    Full Text Available Photoaffinity labeling is a powerful technique for identifying a target protein. A high degree of labeling specificity can be achieved with this method in comparison to chemical labeling. Human serum albumin (HSA and α1-acid glycoprotein (AGP are two plasma proteins that bind a variety of endogenous and exogenous substances. The ligand binding mechanism of these two proteins is complex. Fatty acids, which are known to be transported in plasma by HSA, cause conformational changes and participate in allosteric ligand binding to HSA. HSA undergoes an N-B transition, a conformational change at alkaline pH, that has been reported to result in increased ligand binding. Attempts have been made to investigate the impact of fatty acids and the N-B transition on ligand binding in HSA using ketoprofen and flunitrazepam as photolabeling agents. Meanwhile, plasma AGP is a mixture of genetic variants of the protein. The photolabeling of AGP with flunitrazepam has been utilized to shed light on the topology of the protein ligand binding site. Furthermore, a review of photoaffinity labeling performed on other major plasma proteins will also be discussed. Using a photoreactive natural ligand as a photolabeling agent to identify target protein in the plasma would reduce non-specific labeling.

  5. Preparation and characterization of Protein A-immobilized PVDF and PES membranes

    Directory of Open Access Journals (Sweden)

    N. Akashi

    2015-01-01

    Full Text Available Polyvinylidene fluoride (PVDF and polyether sulfone (PES membranes were activated using low-temperature plasma at atmospheric pressure, and their surface characteristics were investigated. In the plasma-treated PVDF, the XPS data showed that defluorination and oxidation reactions proceeded to 18 and 31%, respectively, at ±4.0 kVp-p for 180 s. Hydroperoxide groups were detected on both the plasma-treated membranes. By decomposing the S2p spectrum, it was proven that the sulfide and sulfo groups were newly formed on the plasma-treated PES. Based on these findings, we proposed an activation mechanism. The SEM images showed that the macrovoid formations were maintained after the plasma treatment. Polyacrylic acid (PAA was grafted on both of the plasma-treated membranes by thermal treatments. Protein A, originating from Staphylococcus aureus, was immobilized on the membrane grafted with PAA using the EDC/Sulfo-NHS system. Adsorption isotherms with a human immunoglobulin G (IgG antibody were fitted with the monolayer Langmuir model, and the maximum binding capacity (qm and equilibrium association constant (Ka were obtained. The ligand densities of the PVDF (pore size 0.45 and 5.0 µm and PES (pore size 0.45 µm membranes were 0.98, 1.42 and 2.06 mg•mL–1, respectively.

  6. Magnetoresistive waves in plasmas

    Science.gov (United States)

    Felber, F. S.; Hunter, R. O., Jr.; Pereira, N. R.; Tajima, T.

    1982-10-01

    The self-generated magnetic field of a current diffusing into a plasma between conductors can magnetically insulate the plasma. Propagation of magnetoresistive waves in plasmas is analyzed. Applications to plasma opening switches are discussed.

  7. Electrosurgical plasmas

    Science.gov (United States)

    Stalder, Kenneth R.; McMillen, Donald F.; Woloszko, Jean

    2005-06-01

    Electrosurgical medical devices based on repetitively pulsed nonequilibrium micron-scale to millimetre-scale plasma discharges in saline solutions are described. The formation of vapour layers (bubbles) around active electrodes appears to be a common feature at moderate (<300 V rms) voltages, and dissociation, excitation and ionization of the vapour in these bubbles produces chemical conditions that are thought to be the source of beneficial tissue removal and treatment. Experimental data are discussed, as are the results of modelling efforts of the plasma chemistry. Hydroxyl radicals, hydrogen atoms and other species are observed spectroscopically and their interactions with collagen, a common component of tissue encountered in surgical situations, are considered. Several pathways by which hydroxyl radicals interacting with collagen can lead to tissue removal are discussed.

  8. Electrosurgical plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Stalder, Kenneth R; McMillen, Donald F; Woloszko, Jean [ArthroCare Corp., Sunnyvale, CA 94085-3523 (United States)

    2005-06-07

    Electrosurgical medical devices based on repetitively pulsed nonequilibrium micron-scale to millimetre-scale plasma discharges in saline solutions are described. The formation of vapour layers (bubbles) around active electrodes appears to be a common feature at moderate (<300 V rms) voltages, and dissociation, excitation and ionization of the vapour in these bubbles produces chemical conditions that are thought to be the source of beneficial tissue removal and treatment. Experimental data are discussed, as are the results of modelling efforts of the plasma chemistry. Hydroxyl radicals, hydrogen atoms and other species are observed spectroscopically and their interactions with collagen, a common component of tissue encountered in surgical situations, are considered. Several pathways by which hydroxyl radicals interacting with collagen can lead to tissue removal are discussed.

  9. 妊娠相关蛋白A对老年急性冠状动脉综合征患者的预后价值%Prognostic value of pregnancy-associated plasma protein A in elderly patients with non-ST segment elevation acute coronary syndrome

    Institute of Scientific and Technical Information of China (English)

    吴凡; 张蔷; 杜鑫; 张宜青; 万征

    2015-01-01

    Objective To study the prognostic value of pregnancy‐associated plasma protein‐A (PAPP‐A ) in elderly patients with NSTEACS .Methods Four hundred and fifty‐five elderly NSTEACS patients were included in this study .Their serum PAPP‐A level was measured .The patients were followed up for 12 months ,during which the adverse cardiovascular events were ob‐served .The patients were divided into high PAPP‐A group (n=147)and low PAPP‐A group (n=308) .The association between serum PAPP‐A level and adverse cardiovascular events was ana‐lyzed .Results At the end of 12 months follow‐up ,the incidence of combined endpoint events was significantly higher in high PAPP‐A group than in low PAPP‐A group (57 .7% vs 24 .4% ,P=0.000) .The sensitivity and specificity of PAPP‐A were 66 .7% and 75.0% for predicting adverse cardiovascular events when it was 23 .5 mU/L .The elevated PAPP‐A level was significantly asso‐ciated with adverse cardiovascular events (OR= 2 .832 ,P=0.006) .The elevated PAPP‐A level was an independent risk factor for poor prognosis (HR=2 .79 ,P=0 .007) .Conclusion PAPP‐A is an effective indicator of prognosis in elderly NSTEACS patients and can thus be used in assess‐ment of risk factors for their poor prognosis .%目的:评价妊娠相关蛋白A(PAPP‐A)对预测老年非ST段抬高急性冠状动脉综合征(NSTEACS)患者的预后临床价值。方法选择老年 NSTEACS 患者455例,测定外周血 PAPP‐A 水平,将患者分为高值组147例(PAPP‐A≥23.5 mU/L)和低值组308例(PAPP‐A <23.5 mU/L ),随访观察12个月不良心血管事件。分析PAPP‐A水平与不良心血管事件关系。结果随访12个月时,高值组复合终点事件发生率高于低值组(57.7% vs 24.4%,P=0.000)。PAPP‐A 界值23.5 mU/L 时,预测不良心血管事件敏感性为66.7%,特异性为75.0%。PAPP‐A升高与不良预后显著相关(OR=2.832

  10. Plasma physics

    CERN Document Server

    Cairns, R A

    1985-01-01

    This book is intended as an introduction to plasma physics at a level suitable for advanced undergraduates or beginning postgraduate students in physics, applied mathematics or astrophysics. The main prerequisite is a knowledge of electromagnetism and of the associated mathematics of vector calculus. SI units are used throughout. There is still a tendency amongst some plasma physics researchers to· cling to C.g.S. units, but it is the author's view that universal adoption of SI units, which have been the internationally agreed standard since 1960, is to be encouraged. After a short introductory chapter, the basic properties of a plasma con­ cerning particle orbits, fluid theory, Coulomb collisions and waves are set out in Chapters 2-5, with illustrations drawn from problems in nuclear fusion research and space physics. The emphasis is on the essential physics involved and (he theoretical and mathematical approach has been kept as simple and intuitive as possible. An attempt has been made to draw attention t...

  11. Plasma pharmacy - physical plasma in pharmaceutical applications.

    Science.gov (United States)

    von Woedtke, Th; Haertel, B; Weltmann, K-D; Lindequist, U

    2013-07-01

    During the last years the use of physical plasma for medical applications has grown rapidly. A multitude of findings about plasma-cell and plasma-tissue interactions and its possible use in therapy have been provided. One of the key findings of plasma medical basic research is that several biological effects do not result from direct plasma-cell or plasma-tissue interaction but are mediated by liquids. Above all, it was demonstrated that simple liquids like water or physiological saline, are antimicrobially active after treatment by atmospheric pressure plasma and that these effects are attributable to the generation of different low-molecular reactive species. Besides, it could be shown that plasma treatment leads to the stimulation of specific aspects of cell metabolism and to a transient and reversible increase of diffusion properties of biological barriers. All these results gave rise to think about another new and innovative field of medical plasma application. In contrast to plasma medicine, which means the direct use of plasmas on or in the living organism for direct therapeutic purposes, this field - as a specific field of medical plasma application - is called plasma pharmacy. Based on the present state of knowledge, most promising application fields of plasma pharmacy might be: plasma-based generation of biologically active liquids; plasma-based preparation, optimization, or stabilization of - mainly liquid - pharmaceutical preparations; support of drug transport across biological barriers; plasma-based stimulation of biotechnological processes.

  12. Changes of Serum Pregnancy-Associated Plasma Protein-A,Placental Growth Factor and Solu-ble Fms-Like Tyrosine Kinase Receptor-1 Concentrations in Preeclampsia Patients%血清PAPP-A、PIGF和sFlt-1在子痫前期患者中的表达及意义

    Institute of Scientific and Technical Information of China (English)

    陈雪; 应豪; 杨慧琳

    2015-01-01

    【目的】探讨血清妊娠相关蛋白A(PAPP‐A)、胎盘生长因子(PLGF)、可溶性Fms样酪氨酸激酶1(sFlt‐1)在子痫前期患者中的表达及意义。【方法】回顾性分析本院2013年2月至2014年6月收治的82例妊娠妇女的临床资料,包括21例轻度子痫前期患者、16例重度子痫前期患者和45例正常妊娠妇女,分别于四个妊娠阶段(12~15周、20~24周、28~32周,35~37周)采用ELISA法检测患者血清中PAPP‐A、PLGF、sFlt‐1的浓度水平并比较。【结果】三组血清PAPP‐A浓度在28~32周和35~37周比较均有显著性差异( P<0.05);轻度和重度子痫前期血清PLGF浓度在20~24周、28~32周、35~37周均显著低于对照组( P <0.05),重度子痫前期在28~32周、35~37周显著低于轻度子痫前期( P <0.05);三组血清sFlt‐1浓度在28~32周、35~37周比较均有显著性差异( P<0.05)。在20~24周、28~32周、35~37周对照组、轻度子痫前期、重度子痫前期sFlt‐1/PLGF值依次升高( P<0.05),且组间比较有显著性差异( P <0.05)。【结论】血清标志物PAPP‐A、PLGF和sFlt‐1对子痫前期诊治有较高的参考价值,sFlt‐1/PLGF更有优势。%[Objective] To explore the expressions and significance of pregnancy‐associated plasma protein‐A (PAPP‐A) ,placental growth factor (PLGF) and soluble fms‐like tyrosine kinase receptor‐1 (sFlt‐1) in pregnant women with preeclampsia .[Methods] Retrospective analysis was performed for 82 pregnant women from February 2013 to June 2014 ,including mild preeclampsia ( n=21) ,severe preeclampsia ( n=16) and 45 normal pregnancy ( n=45) .And enzyme‐linked immunosorbent assay (ELISA) was employed to measure the serum concentrations of PAPP‐A ,PLGF and sFlt‐1 at four gestational periods of 12~15 ,20~24 ,28~32 &35~37 weeks .One way analysis of variation (ANOVA) was used to

  13. Lead-Binding Proteins: A Review

    Directory of Open Access Journals (Sweden)

    Harvey C. Gonick

    2011-01-01

    Full Text Available Lead-binding proteins are a series of low molecular weight proteins, analogous to metallothionein, which segregate lead in a nontoxic form in several organs (kidney, brain, lung, liver, erythrocyte. Whether the lead-binding proteins in every organ are identical or different remains to be determined. In the erythrocyte, delta-aminolevulinic acid dehydratase (ALAD isoforms have commanded the greatest attention as proteins and enzymes that are both inhibitable and inducible by lead. ALAD-2, although it binds lead to a greater degree than ALAD-1, appears to bind lead in a less toxic form. What may be of greater significance is that a low molecular weight lead-binding protein, approximately 10 kDa, appears in the erythrocyte once blood lead exceeds 39 μg/dL and eventually surpasses the lead-binding capacity of ALAD. In brain and kidney of environmentally exposed humans and animals, a cytoplasmic lead-binding protein has been identified as thymosin β4, a 5 kDa protein. In kidney, but not brain, another lead-binding protein has been identified as acyl-CoA binding protein, a 9 kDa protein. Each of these proteins, when coincubated with liver ALAD and titrated with lead, diminishes the inhibition of ALAD by lead, verifying their ability to segregate lead in a nontoxic form.

  14. Plasma Free Metanephrines

    Science.gov (United States)

    ... be limited. Home Visit Global Sites Search Help? Plasma Free Metanephrines Share this page: Was this page helpful? Also known as: Plasma Metanephrines Formal name: Fractionated Plasma Free Metanephrines (Metanephrine ...

  15. Improved plasma accelerator

    Science.gov (United States)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  16. Plasma physics and fusion plasma electrodynamics

    CERN Document Server

    Bers, Abraham

    2016-01-01

    Plasma is a ubiquitous state of matter at high temperatures. The electrodynamics of plasmas encompasses a large number of applications, from understanding plasmas in space and the stars, to their use in processing semiconductors, and their role in controlled energy generation by nuclear fusion. This book covers collective and single particle dynamics of plasmas for fully ionized as well as partially ionized plasmas. Many aspects of plasma physics in current fusion energy generation research are addressed both in magnetic and inertial confinement plasmas. Linear and nonlinear dynamics in hydrodynamic and kinetic descriptions are offered, making both simple and complex aspects of the subject available in nearly every chapter. The approach of dividing the basic aspects of plasma physics as "linear, hydrodynamic descriptions" to be covered first because they are "easier", and postponing the "nonlinear and kinetic descriptions" for later because they are "difficult" is abandoned in this book. For teaching purpose...

  17. Fusion plasma physics

    CERN Document Server

    Stacey, Weston M

    2012-01-01

    This revised and enlarged second edition of the popular textbook and reference contains comprehensive treatments of both the established foundations of magnetic fusion plasma physics and of the newly developing areas of active research. It concludes with a look ahead to fusion power reactors of the future. The well-established topics of fusion plasma physics -- basic plasma phenomena, Coulomb scattering, drifts of charged particles in magnetic and electric fields, plasma confinement by magnetic fields, kinetic and fluid collective plasma theories, plasma equilibria and flux surface geometry, plasma waves and instabilities, classical and neoclassical transport, plasma-materials interactions, radiation, etc. -- are fully developed from first principles through to the computational models employed in modern plasma physics. The new and emerging topics of fusion plasma physics research -- fluctuation-driven plasma transport and gyrokinetic/gyrofluid computational methodology, the physics of the divertor, neutral ...

  18. International movement of plasma and plasma contracting.

    Science.gov (United States)

    Farrugia, A

    2005-01-01

    Plasma fractionation is a global business characterised by technological stability, increasing consolidation and a high level of regulatory oversight. All these factors affect the ease with which plasma derivatives can be accessed in the world market. As domestic regulatory measures in the first world blood economies become increasingly resonant to the precautionary approach, the availability of plasma as a raw material, as well as its cost, become an increasingly significant component in the cost of the final product. This decreases the amount of plasma which fractionators are able to allocate for export activities. Also, regulatory standards in the country of manufacture will reflect priorities in that country which may not be similar to those in export markets, but which will affect entry to those markets. While many countries possess a fractionation capacity, the limiting factor in supply worldwide is the amount of plasma available, and nationalistic drivers for each country to have its own plant are inimical to product safety and supply. Rather, the provision of sufficient supplies of domestic plasma should be the focus of resource allocation, with a choice of an appropriate contract fractionator. However, contract fractionation too may be affected by domestic considerations unrelated to the needs of the country of plasma origin. This chapter will review the global plasma market and the influences on plasma and plasma product movement across national borders. Problems in ensuring adequate safety and supply will be identified, and some tentative approaches to the amelioration of current barriers to the provision of plasma derivatives will be outlined.

  19. Communication through Plasma Sheaths

    CERN Document Server

    Korotkevich, A O; Zakharov, V E

    2007-01-01

    We wish to transmit messages to and from a hypersonic vehicle around which a plasma sheath has formed. For long distance transmission, the signal carrying these messages must be necessarily low frequency, typically 2 GHz, to which the plasma sheath is opaque. The idea is to use the plasma properties to make the plasma sheath appear transparent.

  20. Introduction to plasma dynamics

    CERN Document Server

    Morozov, A I

    2013-01-01

    As the twenty-first century progresses, plasma technology will play an increasing role in our lives, providing new sources of energy, ion-plasma processing of materials, wave electromagnetic radiation sources, space plasma thrusters, and more. Studies of the plasma state of matter not only accelerate technological developments but also improve the understanding of natural phenomena. Beginning with an introduction to the characteristics and types of plasmas, Introduction to Plasma Dynamics covers the basic models of classical diffuse plasmas used to describe such phenomena as linear and shock w

  1. Collisionless plasmas in astrophysics

    CERN Document Server

    Belmont, Gerard; Mottez, Fabrice; Pantellini, Filippo; Pelletier, Guy

    2013-01-01

    Collisionless Plasmas in Astrophysics examines the unique properties of media without collisions in plasma physics. Experts in this field, the authors present the first book to concentrate on collisionless conditions in plasmas, whether close or not to thermal equilibrium. Filling a void in scientific literature, Collisionless Plasmas in Astrophysics explains the possibilities of modeling such plasmas, using a fluid or a kinetic framework. It also addresses common misconceptions that even professionals may possess, on phenomena such as "collisionless (Landau) damping". Abundant illustrations

  2. Colloidal Plasmas : Basic physics of colloidal plasmas

    Indian Academy of Sciences (India)

    C B Dwivedi

    2000-11-01

    Colloidal plasma is a distinct class of the impure plasmas with multispecies ionic composition. The distinction lies in the phase distribution of the impurity-ion species. The ability to tailor the electrostatic interactions between these colloidal particles provides a fertile ground for scientists to investigate the fundamental aspects of the Coulomb phase transition behavior. The present contribution will review the basic physics of the charging mechanism of the colloidal particles as well as the physics of the collective normal mode behavior of the general multi-ion species plasmas. Emphasis will be laid on the clarification of the prevailing confusing ideas about distinct qualities of the various acoustic modes, which are likely to exist in colloidal plasmas as well as in normal multi-ion species plasmas. Introductory ideas about the proposed physical models for the Coulomb phase transition in colloidal plasma will also be discussed.

  3. Nonlinear plasma wave in magnetized plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Bulanov, Sergei V. [Kansai Photon Science Institute, JAEA, Kizugawa, Kyoto 619-0215 (Japan); Prokhorov Institute of General Physics, Russian Academy of Sciences, Moscow 119991 (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny, Moscow region 141700 (Russian Federation); Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K. [Kansai Photon Science Institute, JAEA, Kizugawa, Kyoto 619-0215 (Japan); Hosokai, Tomonao; Zhidkov, Alexei G. [Photon Pioneers Center, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871 (Japan); Japan Science and Technology Agency, CREST, 2-1, Yamadaoka, Suita, Osaka 565-0871 (Japan); Kodama, Ryosuke [Photon Pioneers Center, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2013-08-15

    Nonlinear axisymmetric cylindrical plasma oscillations in magnetized collisionless plasmas are a model for the electron fluid collapse on the axis behind an ultrashort relativisically intense laser pulse exciting a plasma wake wave. We present an analytical description of the strongly nonlinear oscillations showing that the magnetic field prevents closing of the cavity formed behind the laser pulse. This effect is demonstrated with 3D PIC simulations of the laser-plasma interaction. An analysis of the betatron oscillations of fast electrons in the presence of the magnetic field reveals a characteristic “Four-Ray Star” pattern.

  4. Elements of plasma technology

    CERN Document Server

    Wong, Chiow San

    2016-01-01

    This book presents some fundamental aspects of plasma technology that are important for beginners interested to start research in the area of plasma technology . These include the properties of plasma, methods of plasma generation and basic plasma diagnostic techniques. It also discusses several low cost plasma devices, including pulsed plasma sources such as plasma focus, pulsed capillary discharge, vacuum spark and exploding wire; as well as low temperature plasmas such as glow discharge and dielectric barrier discharge which the authors believe may have potential applications in industry. The treatments are experimental rather than theoretical, although some theoretical background is provided where appropriate. The principles of operation of these devices are also reviewed and discussed.

  5. Reviews of plasma physics

    CERN Document Server

    2008-01-01

    "Reviews of Plasma Physics Volume 24," edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence

  6. Reviews of plasma physics

    Energy Technology Data Exchange (ETDEWEB)

    Shafranov, Vitalii Dmitrievich (ed.); Bakunin, Oleg G. (comps.) [Rossijskij Nauchnyj Tsentr ' ' Kurchatovskij Inst.' ' , Moscow (Russian Federation). Nuclear Fusion Inst.; Rozhansky, V. [St. Petersburg State Polytechnical Univ. (Russian Federation)

    2008-07-01

    Reviews of Plasma Physics Volume 24, edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence (orig.)

  7. Prediction of spontaneous preterm delivery from maternal factors, obstetric history and placental perfusion and function at 11-13 weeks.

    Science.gov (United States)

    Beta, Jarek; Akolekar, Ranjit; Ventura, Walter; Syngelaki, Argyro; Nicolaides, Kypros H

    2011-01-01

    To develop a model for prediction of spontaneous delivery before 34 weeks based on maternal factors, placental perfusion and function at 11-13 weeks' gestation. Two groups of studies: first, screening study of maternal characteristics, serum pregnancy-associated plasma protein-A (PAPP-A), free β-human chorionic gonadotrophin (β-hCG) and uterine artery pulsatility index (PI). Second, case-control studies of maternal serum or plasma concentration of placental growth factor (PlGF), placental protein 13 (PP13), a disintegrin and metalloprotease 12 (ADAM12), inhibin-A and activin-A. Regression analysis was used to develop a model for the prediction of spontaneous early delivery. Spontaneous early delivery occurred in 365 (1.1%) of the 34 025 pregnancies. A model based on maternal factors could detect 38.2% of the preterm deliveries in women with previous pregnancies at or beyond 16 weeks and 18.4% in those without, at a false positive rate (FPR) of 10%. In the preterm delivery group, compared with unaffected pregnancies there were no significant differences in the markers of placental perfusion or function, except for PAPP-A which was reduced. Patient-specific risk of preterm delivery is provided by maternal factors and obstetric history. Placental perfusion and function at 11-13 weeks are not altered in pregnancies resulting in spontaneous early delivery. Copyright © 2011 John Wiley & Sons, Ltd.

  8. Effect of Salvia miltiorrhiza on cytokines in patients with unstable angina pectoris

    Institute of Scientific and Technical Information of China (English)

    Shi-Lian Chen; Sheng-Bing Huang

    2016-01-01

    Objective:To investigate the effect of Salvia miltiorrhiza (SM) on cytokines in patients with unstable angina pectoris (UAP).Methods: A total of 50 cases of UAP patients from October 2014 to October 2015 as the research object, randomly divided into treatment group and control group, two groups were treated with conventional bed rest, oxygen inhalation, ECG, nitroglycerin intravenous infusion, beta blockers, aspirin, statins, antiplatelet drug therapy, the treatment group on the basis of salvianolate 200 mg+5% glucose 250 mL (neutralization amount of 0.9% sodium chloride was used in patients with diabetes or glucose insulin) intravenous drip, 1 times/d, two groups were treated for 2 weeks; detected before and after treatment of plasma pregnancy associated plasma protein A (PAPP-A), soluble cell differentiation antigen ligand (sCD40L) and the level of serum interleukin-1 (IL-1), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) level.Results: after the end of treatment, the treatment of PAPP-A and sCD40L levels decreased than the control group, which had statistical significance; treatment group IL-1, IL-6, TNF-α level lower than control group, which had statistical significance.Conclusion:On the basis of conventional treatment combined with salvianolate in treatment of UAP, can inhibit platelet aggregation, control inflammatory reaction, stabilize atherosclerotic plaque, reduce risk of cardiovascular events in therapeutic effect, it is worth clinical promotion.

  9. Hot plasma dielectric tensor

    NARCIS (Netherlands)

    Westerhof, E.

    1996-01-01

    The hot plasma dielectric tensor is discussed in its various approximations. Collisionless cyclotron resonant damping and ion/electron Bernstein waves are discussed to exemplify the significance of a kinetic description of plasma waves.

  10. Special issue: Plasma Conversion

    NARCIS (Netherlands)

    Nozaki, T.; Bogaerts, A.; Tu, X.; van de Sanden, M. C. M.

    2017-01-01

    With growing concern of energy and environmental issues, the combination of plasma and heterogeneous catalysts receives special attention in greenhouse gas conversion, nitrogen fixation and hydrocarbon chemistry. Plasma gas conversion driven by renewable electricity is particularly important for the

  11. A reassessment of biochemical marker distributions in trisomy 21-affected and unaffected twin pregnancies in the first trimester.

    Science.gov (United States)

    Madsen, H N; Ball, S; Wright, D; Tørring, N; Petersen, O B; Nicolaides, K H; Spencer, K

    2011-01-01

    To estimate the difference between levels of the two biochemical markers pregnancy-associated plasma protein-A (PAPP-A) and maternal serum free β-human chorionic gonadotropin (free β-hCG) in twin pregnancies relative to singleton pregnancies and establish an improved screening procedure for chromosomal abnormalities such as trisomy 21 in twin pregnancies. 4843 unaffected and 47 trisomy 21-affected twin pregnancies were included in the study. Chorionicity-specific medians were generated for PAPP-A and free β-hCG from gestational ages 8 to 14 weeks. Multiple of the median values for each of the biochemical markers were calculated. Detection rates and false-positive rates were estimated for screening tests incorporating nuchal translucency and maternal age, with and without biochemistry. Medians for the two biochemical markers for monochorionic and dichorionic twins in unaffected pregnancies show a gestational age-specific increase relative to singleton medians. Allowing for gestation and chorionicity, twin pregnancies affected with trisomy 21 had higher levels of free β-hCG and lower levels of PAPP-A. Adding biochemistry into the risk assessment using a fixed risk cut-off of 1 in 100 increased the detection rate for fetal trisomy 21 in dizygotic twin pregnancies from 78 to 90%, and decreased the false-positive rate from 8.0 to 5.9%. Generation of chorionicity-specific medians for the biochemical markers and their use in risk assessment can improve the performance of first-trimester screening for chromosomal abnormalities in twins to a level comparable with that in singleton pregnancies.

  12. First-Trimester Combined Screening Is Effective for the Detection of Unbalanced Chromosomal Translocations at 11 to 12 Weeks of Gestation

    Science.gov (United States)

    Huang, ShangYu; Chang, ChiaLin; Hsiao, ChingHua; Soong, YungKuei; Duan, Tao

    2014-01-01

    The first trimester combined screening, which analyzes fetal nuchal translucency and levels of free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein A (PAPP-A) in maternal serum, is routinely used to detect abnormal pregnancies associated with Down syndrome and other trisomy aneuploidies. Based on the hypothesis that major chromosomal translocations could lead to similar biochemical and developmental outcomes during early embryo development, we compared these markers among pregnancies with normal, balanced, or unbalanced fetal karyotypes. Among the parents, 71 (73%) carry balanced reciprocal translocation and 26 (27%) have Robertsonian translocation. Of the 97 pregnancies tested, 39 (40%), 37 (37%), and 22 (23%) fetuses had normal karyotype, balanced chromosomal translocations, and unbalanced chromosomal translocations, respectively. Importantly, we found that pregnancies with an unbalanced translocation had significantly higher free β-hCG multiple of the median (MoM) and larger nuchal translucency thickness than those with normal karyotype or balanced translocations. Analysis showed that the area under a receiver operating characteristic curve (AUC) is 0.716, 0.820, and 0.936 for free β-hCG MoM, PAPP-A MoM, and fetal nuchal translucency, respectively. When these 3 independent factors were combined, the AUC reached 0.976. In addition, logistic regression showed that the most optimal model for predicting an unbalanced chromosomal translocation is a combination of PAPP-A and nuchal translucency with an AUC of 0.980. Therefore, the first trimester combined screening is not only effective in the screening of Down syndrome and other trisomy abnormalities but also has high sensitivity for the detection of unbalanced chromosomal translocations in fetuses. PMID:24177714

  13. Screening for trisomy 21 with maternal age, fetal nuchal translucency and maternal serum biochemistry at 11-14 weeks: a regional experience from Germany.

    Science.gov (United States)

    Soergel, P; Pruggmayer, M; Schwerdtfeger, R; Muhlhaus, K; Scharf, A

    2006-01-01

    To examine the efficacy of first trimester screening for trisomy 21 using a combination of maternal age, fetal nuchal translucency (NT), maternal serum free beta-human chorionic gonadotropin (free beta-hCG) and pregnancy-associated plasma protein A (PAPP-A) in a regional setting [maternity unit of the Women's University Hospital, Hannover Medical School (study center); two regional private centers for prenatal diagnosis and human genetics; laboratory for prenatal diagnosis and human genetics]. Fetal NT, crown-rump length, maternal serum free beta-hCG and PAPP-A were measured at 11-14 weeks of gestation. Risk calculation was carried out using the FMF computer algorithm. The patients were informed and counseled about possible invasive test options if the risk was 1 in 300 or greater. Fetal outcome was obtained by questionnaires given to the patients or sent to their gynecologists. The detection and false-positive rates for the different screening strategies were calculated. Pregnancy outcome was obtained in 2,497 cases, of which 2,196 cases had completed first trimester screening with NT and maternal serum biochemistry and 301 additional cases had NT measurement only. The median age was 32.5 years. In our population 11 affected fetuses were found. The estimated risk for trisomy 21 was 1 in 300 or greater in 64, 82, 88 and 88% of affected fetuses using maternal age alone, in combination with nuchal translucency, with maternal serum biochemical markers or with both NT and biochemical markers for a false-positive rate of 28.2, 5.1, 15.3 and 4.0%. First trimester screening using maternal age, NT, free beta-hCG and PAPP-A is highly effective for the detection of trisomy 21 and is associated with a sensitivity of about 90% for 5% false-positive patients. Copyright 2006 S. Karger AG, Basel.

  14. First trimester risk assessment for trisomy 21 in twin pregnancies combining nuchal translucency and first trimester biochemical markers.

    Science.gov (United States)

    Prats, Pilar; Rodríguez, Ignacio; Comas, Carmina; Puerto, Bienvenido

    2012-10-01

    The aim is to describe the performance of first-trimester combined risk assessment in twin pregnancies. Maternal serum free beta-human chorionic gonadotrophin and pregnancy-associated plasma protein A (PAPP-A) were determined at 8 to 12 weeks and fetal nuchal translucency (NT) was measured at 11 to 13+6 weeks. The individual risk was estimated for each fetus using the combined test in dichorionic twins. In monochorionic twins, the mean risk assessment of the two fetuses was used. An invasive diagnostic procedure was offered when the risk was ≥ 1 : 270 in either one of the fetuses. From February 2007 to June 2011, 447 twin pregnancies were enrolled in this study. There were 402 (89.9%) dichorionic and 45 (10.1%) monochorionic twins. In dichorionic twins, mean crown-rump length (CRL) was 63.9 mm; median NT multiples of the median (MoM) was 0.97; median Β-hCG was MoM 1.74; median PAPP-A was 1.72. In monochorionic twins, mean CRL was 61.9 mm; median NT MoM was 0. 98; median Β-hCG MoM was 1.44; and median PAPP-A was 1.51. Two pregnancies with Down syndrome were detected by first trimester screening, both in dichorionic twins. The false positive rate was 5.7% (95% confidence interval 4.1-7.3) and 4.4% (95% confidence interval 0.1-8.8%) in dichorionic and monochorionic twins, respectively. The combined test in twins appears to be a good method for Down syndrome screening with a high detection rate and an acceptable false-positive rate. © 2012 John Wiley & Sons, Ltd.

  15. Microwave Argon Plasma Torch

    Science.gov (United States)

    2013-07-01

    an electron-ion pair in the discharge. Fig. 2. EEDF is non - Maxwellian and changes along the plasma column The electron–neutral collision...plasma radius. Even at atmospheric pressure the EEDF is non - Maxwellian and it is changing along the plasma column. ...18 31st ICPIG, July 14-19, 2013, Granada, Spain EEDF usually strongly differs from Maxwellian and chages along the plasma column (this is

  16. Introduction to Plasma Physics

    Science.gov (United States)

    Gurnett, Donald A.; Bhattacharjee, Amitava

    2017-03-01

    Preface; 1. Introduction; 2. Characteristic parameters of a plasma; 3. Single particle motions; 4. Waves in a cold plasma; 5. Kinetic theory and the moment equations; 6. Magnetohydrodynamics; 7. MHD equilibria and stability; 8. Discontinuities and shock waves; 9. Electrostatic waves in a hot unmagnetized plasma; 10. Waves in a hot magnetized plasma; 11. Nonlinear effects; 12. Collisional processes; Appendix A. Symbols; Appendix B. Useful trigonometric identities; Appendix C. Vector differential operators; Appendix D. Vector calculus identities; Index.

  17. Plasma physics an introduction

    CERN Document Server

    Fitzpatrick, Richard

    2014-01-01

    Plasma Physics: An Introduction is based on a series of university course lectures by a leading name in the field, and thoroughly covers the physics of the fourth state of matter. This book looks at non-relativistic, fully ionized, nondegenerate, quasi-neutral, and weakly coupled plasma. Intended for the student market, the text provides a concise and cohesive introduction to plasma physics theory, and offers a solid foundation for students wishing to take higher level courses in plasma physics.

  18. Plasma membrane ATPases

    DEFF Research Database (Denmark)

    Palmgren, Michael Broberg; Bækgaard, Lone; Lopez Marques, Rosa Laura

    2011-01-01

    The plasma membrane separates the cellular contents from the surrounding environment. Nutrients must enter through the plasma membrane in order to reach the cell interior, and toxic metabolites and several ions leave the cell by traveling across the same barrier. Biological pumps in the plasma me...

  19. Plasma in dentistry

    OpenAIRE

    Cha, Seunghee; Park, Young-Seok

    2014-01-01

    This review describes the contemporary aspects of plasma application in dentistry. Previous studies on plasma applications were classified into two categories, surface treatment and direct applications, and were reviewed, respectively according to the approach. The current review discussed modification of dental implant surface, enhancing of adhesive qualities, enhancing of polymerization, surface coating and plasma cleaning under the topics of surface treatment. Microbicidal activities, deco...

  20. The Plasma Universe

    Science.gov (United States)

    Suplee, Curt

    2009-09-01

    Preface; 1. The fourth state of matter; 2. The music and dance of plasmas; 3. The Sun-Earth connection; 4. Bringing the Sun to Earth: the story of controlled thermonuclear fusion; 5. The cosmic plasma theater: galaxies, stars, and accretion disks; 6. Putting plasmas to work; Index.

  1. Cyclotron waves in plasma

    CERN Document Server

    Lominadze, D G

    2013-01-01

    Cyclotron Waves in Plasma is a four-chapter text that covers the basic physical concepts of the theory of cyclotron waves and cyclotron instabilities, brought about by the existence of steady or alternating plasma currents flowing perpendicular to the magnetic field.This book considers first a wide range of questions associated with the linear theory of cyclotron oscillations in equilibrium plasmas and in electron plasmas in metals and semiconductors. The next chapter deals with the parametric excitation of electron cyclotron oscillations in plasma in an alternating electric field. A chapter f

  2. Plasma Therapy: An Overview

    Directory of Open Access Journals (Sweden)

    Rajkumar Diwan

    2011-01-01

    Full Text Available Definition: Plasma, the fourth state of matter, is a collection of charged particles (electrons, ions, neutral atoms. Recent demonstration of plasma technology in treatment of living cells, tissue and organs are creating a new field at the intersection of plasma science and technology with biology and medicine known as plasma medicine. Plasma medicine is one of the newest fields of modem applied plasma chemistry. It appeared several years ago and comprises studies concerning the direct action of low-temperature, one atmosphere air plasma (cold plasma/nonthermal plasmalnonequilibrium on body tissues for various noninvasive therapeutic treatments or diagnostics purpose. The study of plasma holds promise for a myriad of applications ranging from lasers and electronics, hazardous decontamination, sterilization and disinfection of foods, soil, water, instruments, to medical uses in wound healing and treating certain types of tumors and cancers. Plasma represents a new state-of-the-art sterilization and disinfection treatment for certain oral and environmental pathogens, heat-sensitive materials, hard and soft surfaces, and may assist health care facilities in the management of various health concerns. The role that low temperature atmospheric pressure plasma (LTAPP could play in the inactivation of pathogenic microorganisms might prove to be a new, faster, more economical alternative.

  3. Arc Plasma Torch Modeling

    CERN Document Server

    Trelles, J P; Vardelle, A; Heberlein, J V R

    2013-01-01

    Arc plasma torches are the primary components of various industrial thermal plasma processes involving plasma spraying, metal cutting and welding, thermal plasma CVD, metal melting and remelting, waste treatment and gas production. They are relatively simple devices whose operation implies intricate thermal, chemical, electrical, and fluid dynamics phenomena. Modeling may be used as a means to better understand the physical processes involved in their operation. This paper presents an overview of the main aspects involved in the modeling of DC arc plasma torches: the mathematical models including thermodynamic and chemical non-equilibrium models, turbulent and radiative transport, thermodynamic and transport property calculation, boundary conditions and arc reattachment models. It focuses on the conventional plasma torches used for plasma spraying that include a hot-cathode and a nozzle anode.

  4. Laminar Plasma Dynamos

    CERN Document Server

    Wang, Z; Barnes, C W; Barnes, D C; Wang, Zhehui; Pariev, Vladimir I.; Barnes, Cris W.; Barnes, Daniel C.

    2002-01-01

    A new kind of dynamo utilizing flowing laboratory plasmas has been identified. Conversion of plasma kinetic energy to magnetic energy is verified numerically by kinematic dynamo simulations for magnetic Reynolds numbers above 210. As opposed to intrinsically-turbulent liquid-sodium dynamos, the proposed plasma dynamos correspond to laminar flow topology. Modest plasma parameters, 1-20 eV temperatures, 10^{19}-10^{20} m^{-3} densities in 0.3-1.0 m scale-lengths driven by velocities on the order of the Alfven Critical Ionization Velocity (CIV), self-consistently satisfy the conditions needed for the magnetic field amplication. Growth rates for the plasma dynamos are obtained numerically with different geometry and magnetic Reynolds numbers. Magnetic-field-free coaxial plasma guns can be used to sustain the plasma flow and the dynamo.

  5. Plasma polymerization by Softplasma

    DEFF Research Database (Denmark)

    Jiang, J.; Wu, Zhenning; Benter, Maike

    2008-01-01

    In the late 19th century, the first depositions - known today as plasma polymers, were reported. In the last century, more and more research has been put into plasma polymers. Many different deposition systems have been developed. [1, 2] Shi F. F. broadly classified them into internal electrode......, external electrode, and electrodeless microwave or high frequency reactors. [3] Softplasma™ is an internal electrode plasma setup powered by low frequenc~ gower supply. It was developed in late 90s for surface treatment of silicone rubber. [ ]- 5] It is a low pressure, low electron density, 3D homogenous...... plasma. In this study, we are presenting the surface modification"pf polymers by plasma polymerization using Softplasma™. Softplasma™ can be used for two major types of polymerization: polymerization of vinyl monomers, where plasma acts as initiator; chemical vapour deposition, where plasma acts...

  6. Plasmas for medicine

    Science.gov (United States)

    von Woedtke, Th.; Reuter, S.; Masur, K.; Weltmann, K.-D.

    2013-09-01

    Plasma medicine is an innovative and emerging field combining plasma physics, life science and clinical medicine. In a more general perspective, medical application of physical plasma can be subdivided into two principal approaches. (i) “Indirect” use of plasma-based or plasma-supplemented techniques to treat surfaces, materials or devices to realize specific qualities for subsequent special medical applications, and (ii) application of physical plasma on or in the human (or animal) body to realize therapeutic effects based on direct interaction of plasma with living tissue. The field of plasma applications for the treatment of medical materials or devices is intensively researched and partially well established for several years. However, plasma medicine in the sense of its actual definition as a new field of research focuses on the use of plasma technology in the treatment of living cells, tissues, and organs. Therefore, the aim of the new research field of plasma medicine is the exploitation of a much more differentiated interaction of specific plasma components with specific structural as well as functional elements or functionalities of living cells. This interaction can possibly lead either to stimulation or inhibition of cellular function and be finally used for therapeutic purposes. During recent years a broad spectrum of different plasma sources with various names dedicated for biomedical applications has been reported. So far, research activities were mainly focused on barrier discharges and plasma jets working at atmospheric pressure. Most efforts to realize plasma application directly on or in the human (or animal) body for medical purposes is concentrated on the broad field of dermatology including wound healing, but also includes cancer treatment, endoscopy, or dentistry. Despite the fact that the field of plasma medicine is very young and until now mostly in an empirical stage of development yet, there are first indicators of its enormous

  7. Nonlinear Plasma Wave in Magnetized Plasmas

    CERN Document Server

    Bulanov, Sergei V; Kando, Masaki; Koga, James K; Hosokai, Tomonao; Zhidkov, Alexei G; Kodama, Ryosuke

    2013-01-01

    Nonlinear axisymmetric cylindrical plasma oscillations in magnetized collisionless plasmas are a model for the electron fluid collapse on the axis behind an ultrashort relativisically intense laser pulse exciting a plasma wake wave. We present an analytical description of the strongly nonlinear oscillations showing that the magnetic field prevents closing of the cavity formed behind the laser pulse. This effect is demonstrated with 3D PIC simulations of the laser-plasma interaction. An analysis of the betatron oscillations of fast electrons in the presence of the magnetic field reveals a characteristic "Four-Ray Star" pattern which has been observed in the image of the electron bunch in experiments [T. Hosokai, et al., Phys. Rev. Lett. 97, 075004 (2006)].

  8. Plasma Biomedicine in Orthopedics

    Science.gov (United States)

    Hamaguchi, Satsohi

    2012-10-01

    Various effects of plasmas irradiation on cells, tissues, and biomaterials relevant for orthopedic applications have been examined. For direct application of plasmas to living cells or tissues, dielectric barrier discharges (DBDs) with helium flows into ambient air were used. For biomaterial processing, on the other hand, either helium DBDs mentioned above or low-pressure discharges generated in a chamber were used. In this presentation, plasma effects on cell proliferation and plasma treatment for artificial bones will be discussed. First, the conditions for enhanced cell proliferation in vitro by plasma applications have been examined. The discharge conditions for cell proliferation depend sensitively on cell types. Since cell proliferation can be enhanced even when the cells are cultured in a plasma pre-treated medium, long-life reactive species generated in the medium by plasma application or large molecules (such as proteins) in the medium modified by the plasma are likely to be the cause of cell proliferation. It has been found that there is strong correlation between (organic) hydroperoxide generation and cell proliferation. Second, effects of plasma-treated artificial bones made of porous hydroxyapatite (HA) have been examined in vitro and vivo. It has been found that plasma treatment increases hydrophilicity of the surfaces of microscopic inner pores, which directly or indirectly promotes differentiation of mesenchymal stem cells introduced into the pores and therefore causes faster bone growth. The work has been performed in collaboration with Prof. H. Yoshikawa and his group members at the School of Medicine, Osaka University.

  9. Plasma detachment in linear devices

    Science.gov (United States)

    Ohno, N.

    2017-03-01

    Plasma detachment research in linear devices, sometimes called divertor plasma simulators, is reviewed. Pioneering works exploring the concept of plasma detachment were conducted in linear devices. Linear devices have contributed greatly to the basic understanding of plasma detachment such as volume plasma recombination processes, detached plasma structure associated with particle and energy transport, and other related issues including enhancement of convective plasma transport, dynamic response of plasma detachment, plasma flow reversal, and magnetic field effect. The importance of plasma detachment research using linear devices will be highlighted aimed at the design of future DEMO.

  10. Advanced plasma diagnostics for plasma processing

    Science.gov (United States)

    Malyshev, Mikhail Victorovich

    1999-10-01

    A new, non-intrusive, non-perturbing diagnostic method was developed that can be broadly applied to low pressure, weakly ionized plasmas and glow discharges-trace rare gases optical emission spectroscopy (TRG-OES). The method is based on a comparison of intensities of atomic emission from trace amounts of inert gases (He, Ne, Ar, Kr, and Xe) that are added to the discharge to intensities calculated from the theoretical model. The model assumes a Maxwellian electron energy distribution function (EEDF), computes the population of emitting levels both from the ground state and the metastable states of rare gases, and from the best fit between theory and experiment determines electron temperature (Te). Subject to conditions, TRG-OES can also yield electron density or its upper or lower limit. From the comparison of the emission from levels excited predominantly by high energy electrons to that excited by low energy electrons, information about the EEDF can be obtained. The use of TRG-OES also allows a traditionally qualitative actinometry technique (determination of concentration of radical species in plasma through optical emission) to become a precise quantitative method by including Te and rare gases metastables effects. A combination of TRG-OES, advanced actinometry, and Langmuir probe measurements was applied to several different plasma reactors and regimes of operation. Te measurements and experiments to correct excitation cross section were conducted in a laboratory helical resonator. Two chamber configuration of a commercial (Lam Research) metal etcher were studied to determine the effects of plasma parameters on plasma-induced damage. Two different methods (RF inductive coupling and ultra-high frequency coupling) for generating a plasma in a prototype reactor were also studied. Pulsed plasmas, a potential candidate to eliminate the plasma-induced damage to microelectronics devices that occurs in manufacturing due to differential charging of the wafer, have

  11. Pulsed plasma arc cladding

    Institute of Scientific and Technical Information of China (English)

    龙; 白钢; 李振民; 张赋升; 杨思乾

    2004-01-01

    A prototype of Pulsed Plasma Arc Cladding system was developed, in which single power source supplies both transferred plasma arc (TPA) and non-transferred plasma arc (N-TPA). Both plasmas work in turn in a high frequency controlled by an IGBT connecting nozzle and workpiece. The working frequency of IGBT ranges from 50 ~ 7000Hz, in which the plasmas can work in turn smoothly. Higher than 500 Hz of working frequency is suggested for promotion of cladding quality and protection of IGBT. Drag phenomenon of TPA intensifies as the frequency goes up, which tends to increase the current proportion of TPA and suppress N-TPA. The occupation ratio of IGBT can be regulated from 5% ~ 95%, which balances the power supplies of both plasmas. An occupation ratio higher than 50% gives adequate proportion of arc current for N-TPA to preheat powder.

  12. Introduction to Complex Plasmas

    CERN Document Server

    Bonitz, Michael; Ludwig, Patrick

    2010-01-01

    Complex plasmas differ from traditional plasmas in many ways: these are low-temperature high pressure systems containing nanometer to micrometer size particles which may be highly charged and strongly interacting. The particles may be chemically reacting or be in contact with solid surfaces, and the electrons may show quantum behaviour. These interesting properties have led to many applications of complex plasmas in technology, medicine and science. Yet complex plasmas are extremely complicated, both experimentally and theoretically, and require a variety of new approaches which go beyond standard plasma physics courses. This book fills this gap presenting an introduction to theory, experiment and computer simulation in this field. Based on tutorial lectures at a very successful recent Summer Institute, the presentation is ideally suited for graduate students, plasma physicists and experienced undergraduates.

  13. Ultracold Neutral Plasmas

    CERN Document Server

    Killian, T C; Gupta, P; Laha, S; Martinez, Y N; Mickelson, P G; Nagel, S B; Saenz, A D; Simien, C E; Killian, Thomas C.

    2005-01-01

    Ultracold neutral plasmas are formed by photoionizing laser-cooled atoms near the ionization threshold. Through the application of atomic physics techniques and diagnostics, these experiments stretch the boundaries of traditional neutral plasma physics. The electron temperature in these plasmas ranges from 1-1000 K and the ion temperature is around 1 K. The density can approach $10^{11}$ cm$^{-3}$. Fundamental interest stems from the possibility of creating strongly-coupled plasmas, but recombination, collective modes, and thermalization in these systems have also been studied. Optical absorption images of a strontium plasma, using the Sr$^+$ ${^2S_{1/2}} -> {^2P_{1/2}}$ transition at 422 nm, depict the density profile of the plasma, and probe kinetics on a 50 ns time-scale. The Doppler-broadened ion absorption spectrum measures the ion velocity distribution, which gives an accurate measure of the ion dynamics in the first microsecond after photoionization.

  14. What is a plasma?

    Energy Technology Data Exchange (ETDEWEB)

    Intrator, Thomas P. [Los Alamos National Laboratory

    2012-08-30

    This introduction will define the plasma fourth state of matter, where we find plasmas on earth and beyond, and why they are useful. There are applications to many consumer items, fusion energy, scientific devices, satellite communications, semiconductor processing, spacecraft propulsion, and more. Since 99% of our observable universe is ionized gas, plasma physics determines many important features of astrophysics, space physics, and magnetosphere physics in our solar system. We describe some plasma characteristics, examples in nature, some useful applications, how to create plasmas. A brief introduction to the theoretical framework includes the connection between kinetic and fluid descriptions, quasi neutrality, Debye shielding, ambipolar electric fields, some plasma waves. Hands-on demonstrations follow. More complete explanations will follow next week.

  15. Pulsed plasma electron sourcesa)

    Science.gov (United States)

    Krasik, Ya. E.; Yarmolich, D.; Gleizer, J. Z.; Vekselman, V.; Hadas, Y.; Gurovich, V. Tz.; Felsteiner, J.

    2009-05-01

    There is a continuous interest in research of electron sources which can be used for generation of uniform electron beams produced at E ≤105 V/cm and duration ≤10-5 s. In this review, several types of plasma electron sources will be considered, namely, passive (metal ceramic, velvet and carbon fiber with and without CsI coating, and multicapillary and multislot cathodes) and active (ferroelectric and hollow anodes) plasma sources. The operation of passive sources is governed by the formation of flashover plasma whose parameters depend on the amplitude and rise time of the accelerating electric field. In the case of ferroelectric and hollow-anode plasma sources the plasma parameters are controlled by the driving pulse and discharge current, respectively. Using different time- and space-resolved electrical, optical, spectroscopical, Thomson scattering and x-ray diagnostics, the parameters of the plasma and generated electron beam were characterized.

  16. Space plasma physics research

    Science.gov (United States)

    Comfort, Richard H.; Horwitz, James L.

    1993-01-01

    During the course of this grant, work was performed on a variety of topics and there were a number of significant accomplishments. A summary of these accomplishments is included. The topics studied include empirical model data base, data reduction for archiving, semikinetic modeling of low energy plasma in the inner terrestrial magnetosphere and ionosphere, O(+) outflows, equatorial plasma trough, and plasma wave ray-tracing studies. A list of publications and presentations which have resulted from this research is also included.

  17. Atmospheric Plasma Depainting

    Science.gov (United States)

    2014-11-19

    Plasma Carbon Dioxide Water Vapor 11 Atmospheric Plasma Depainting, ASETSDefense, Nov 19, 2014 Features and Benefits of APCR Technology Feature...Depainting, ASETSDefense, Nov 19, 2014 14 APC on Aluminum Removal to Primer RAM on Carbon Fiber Partial Topcoat Removal APC Topcoat RAM...60Hz Plasma Flux™ Power Supply VENT To Facility HEPA <= Filtration COTS Six-Axis Robot Aircraft part Particulate Collection System

  18. Plasma nitriding of steels

    CERN Document Server

    Aghajani, Hossein

    2017-01-01

    This book focuses on the effect of plasma nitriding on the properties of steels. Parameters of different grades of steels are considered, such as structural and constructional steels, stainless steels and tools steels. The reader will find within the text an introduction to nitriding treatment, the basis of plasma and its roll in nitriding. The authors also address the advantages and disadvantages of plasma nitriding in comparison with other nitriding methods. .

  19. The plasma membrane proteome of germinating barley embryos

    DEFF Research Database (Denmark)

    Hynek, Radovan; Svensson, Birte; Jensen, O.N.

    2009-01-01

    was used to reduce soluble protein contamination and enrich for hydrophobic proteins. Sixty-one proteins in 14 SDS-PAGE bands were identified by LC-MS/MS and database searches. The identifications provide new insight into the plasma membrane functions in seed germination.......Cereal seed germination involves a complex coordination between different seed tissues. Plasma membranes must play crucial roles in coordination and execution of germination; however, very little is known about seed plasma membrane proteomes due to limited tissue amounts combined...... with amphiphilicity and low abundance of membrane proteins. A fraction enriched in plasma membranes was prepared from embryos dissected from 18 h germinated barley seeds using aqueous two-phase partitioning. Reversed-phase chromatography on C-4 resin performed in micro-spin columns with stepwise elution by 2-propanol...

  20. New Predictive Model at 11(+0) to 13(+6) Gestational Weeks for Early-Onset Preeclampsia With Fetal Growth Restriction.

    Science.gov (United States)

    Chang, Ying; Chen, Xu; Cui, Hong-Yan; Li, Xing; Xu, Ya-Ling

    2017-05-01

    The aim of the present study was to determine a predictive model for early-onset preeclampsia with fetal growth restriction (FGR) to be used at 11(+0) to 13(+6) gestational weeks, by combining the maternal serum level of pregnancy-associated plasma protein-A (PAPP-A), placental growth factor (PLGF), placental protein 13 (PP13), soluble endoglin (sEng), mean arterial pressure (MAP), and uterine artery Doppler. This was a retrospective cohort study of 4453 pregnant women. Uterine artery Doppler examination was conducted in the first trimester. Maternal serum PAPP-A, PLGF, PP13, and sEng were measured. Mean arterial pressure was obtained. Women were classified as with/without early-onset preeclampsia, and women with preeclampsia were classified as with/without FGR. Receiver operating characteristic analysis was performed to determine the value of the model. There were 30 and 32 pregnant women with early-onset preeclampsia with and without FGR. The diagnosis rate of early-onset preeclampsia with FGR was 67.4% using the predictive model when the false positive rate was set at 5% and 73.2% when the false positive rate was 10%. The predictive model (MAP, uterine artery Doppler measurements, and serum biomarkers) had some predictive value for the early diagnosis (11(+0) to 13(+6) gestational weeks) of early-onset preeclampsia with FGR.

  1. Increased Levels of Oxidative Stress Markers, Soluble CD40 Ligand, and Carotid Intima-Media Thickness Reflect Acceleration of Atherosclerosis in Male Patients with Ankylosing Spondylitis in Active Phase and without the Classical Cardiovascular Risk Factors

    Science.gov (United States)

    Cholewka, Armand; Sieroń, Karolina; Sieroń, Aleksander

    2017-01-01

    Objective The primary aim of the study was to assess levels of oxidative stress markers, soluble CD40 ligand (sCD40L), serum pregnancy-associated plasma protein-A (PAPP-A), and placental growth factor (PlGF) as well as carotid intima-media thickness (IMT) in patients with ankylosing spondylitis (AS) with active phase without concomitant classical cardiovascular risk factors. Material and methods The observational study involved 96 male subjects: 48 AS patients and 48 healthy ones, who did not differ significantly regarding age, BMI, comorbid disorders, and distribution of classical cardiovascular risk factors. In both groups, we estimated levels of oxidative stress markers, lipid profile, and inflammation parameters as well as sCD40L, serum PAPP-A, and PlGF. In addition, we estimated carotid IMT in each subject. Results The study showed that markers of oxidative stress, lipid profile, and inflammation, as well as sCD40L, PlGF, and IMT, were significantly higher in the AS group compared to the healthy group. Conclusion Our results demonstrate that ankylosing spondylitis may be associated with increased risk for atherosclerosis. PMID:28883908

  2. Increased Levels of Oxidative Stress Markers, Soluble CD40 Ligand, and Carotid Intima-Media Thickness Reflect Acceleration of Atherosclerosis in Male Patients with Ankylosing Spondylitis in Active Phase and without the Classical Cardiovascular Risk Factors

    Directory of Open Access Journals (Sweden)

    Agata Stanek

    2017-01-01

    Full Text Available Objective. The primary aim of the study was to assess levels of oxidative stress markers, soluble CD40 ligand (sCD40L, serum pregnancy-associated plasma protein-A (PAPP-A, and placental growth factor (PlGF as well as carotid intima-media thickness (IMT in patients with ankylosing spondylitis (AS with active phase without concomitant classical cardiovascular risk factors. Material and methods. The observational study involved 96 male subjects: 48 AS patients and 48 healthy ones, who did not differ significantly regarding age, BMI, comorbid disorders, and distribution of classical cardiovascular risk factors. In both groups, we estimated levels of oxidative stress markers, lipid profile, and inflammation parameters as well as sCD40L, serum PAPP-A, and PlGF. In addition, we estimated carotid IMT in each subject. Results. The study showed that markers of oxidative stress, lipid profile, and inflammation, as well as sCD40L, PlGF, and IMT, were significantly higher in the AS group compared to the healthy group. Conclusion. Our results demonstrate that ankylosing spondylitis may be associated with increased risk for atherosclerosis.

  3. Are serum protein biomarkers derived from proteomic analysis useful in screening for trisomy 21 at 11-13 weeks?

    Science.gov (United States)

    Mastricci, Anna Lucia; Akolekar, Ranjit; Kuppusamy, Ramesh; Ahmed, Mustafa; Nicolaides, Kypros H

    2011-01-01

    The aim of this study is to identify potential biomarkers for fetal trisomy 21 from previous publications using proteomic techniques and examine the potential value of such biomarkers in early screening for this aneuploidy. This was a case-control study of 25 pregnancies with fetal trisomy 21 and 50 euploid controls undergoing first-trimester screening for aneuploidies by a combination of maternal age, fetal nuchal translucency (NT) thickness and maternal serum free β-human chorionic gonadotrophin (β-hCG) and pregnancy-associated plasma protein-A (PAPP-A). The maternal serum concentrations of afamin, apolipoprotein E, clusterin, ceruloplasmin, epidermal growth factor, fetuin-A, pigment epithelium-derived factor glycoprotein and transthyretin were determined using an ELISA and compared in the euploid and trisomy 21 groups. In pregnancies with fetal trisomy 21, the median maternal age, fetal NT thickness and serum free β-hCG were increased, whereas serum PAPP-A was decreased. However, there were no significant differences between cases and controls in any of the biomarkers. Proteins identified as potential biomarkers for trisomy 21 using proteomic techniques have not been found to be useful in early screening for this aneuploidy. Copyright © 2011 S. Karger AG, Basel.

  4. First-trimester contingent screening for trisomies 21, 18 and 13 by biomarkers and maternal blood cell-free DNA testing.

    Science.gov (United States)

    Nicolaides, K H; Syngelaki, A; Poon, L C; Gil, M M; Wright, D

    2014-01-01

    To examine potential performance of screening for trisomies by cell-free (cf) DNA testing in maternal blood contingent on results of first-line testing by combinations of fetal translucency thickness (NT), fetal heart rate (FHR), ductus venosus pulsatility index (DV PIV), and serum-free β-human chorionic gonadotropin (β-hCG), pregnancy-associated plasma protein-A (PAPP-A), placental growth factor (PLGF) and α-fetoprotein (AFP). Performance was estimated for firstly, screening by cfDNA in all pregnancies and secondly, cfDNA testing contingent on results of first-line testing by combinations of ultrasound and biochemical markers. In first-line screening by cfDNA testing, the detection rate for trisomy 21 and trisomies 18 or 13 would be 99 and 96%, respectively, after invasive testing in 1% of the population. In contingent screening, a detection rate of 98% for trisomy 21 and 96% for trisomy 18 or 13, at an invasive testing rate of 0.7%, can be achieved by carrying out cfDNA testing in about 35, 20 and 11% of cases identified by first-line screening with the combined test alone (age, NT, FHR, β-hCG, PAPP-A), the combined test plus PLGF and AFP and the combined test plus PLGF, AFP and DV PIV, respectively. Effective first-trimester screening for trisomies can be achieved by contingent screening incorporating biomarkers and cfDNA testing. © 2013 S. Karger AG, Basel.

  5. Ductus venosus in the first trimester: contribution to screening of chromosomal, cardiac defects and monochorionic twin complications.

    Science.gov (United States)

    Maiz, Nerea; Nicolaides, Kypros H

    2010-01-01

    In the first trimester the ductus venosus can be easily identified with color Doppler and a ductus venosus waveform can be obtained by pulsed Doppler. At 11-13 weeks the prevalence of abnormal a-wave in the ductus venosus is inversely related to fetal crown-rump length and maternal serum pregnancy-associated plasma protein-A (PAPP-A), increases with fetal nuchal translucency (NT) thickness and is more common in women of Black racial origin and in fetuses with abnormal karyotype or cardiac defects. Ductus venosus flow provides an independent contribution in the prediction of chromosomal abnormalities when combined with NT and the maternal serum markers of PAPP-A and free beta-hCG, increasing the detection rate to 96% at a false-positive rate of 2.6%. Abnormal ductus venosus flow increases the risk of cardiac defects in fetuses with NT above the 95th centile, and it may increase the risk in fetuses with normal NT. In twin pregnancies, abnormal ductus venosus flow is associated with chromosomal abnormalities and cardiac defects. In monochorionic twins, abnormal flow in the ductus venosus in at least 1 of the fetuses increases the risk of developing twin-to-twin transfusion syndrome. Copyright (c) 2010 S. Karger AG, Basel.

  6. Plasma adiabatic lapse rate

    CERN Document Server

    Amendt, Peter; Wilks, Scott

    2012-01-01

    The plasma analog of an adiabatic lapse rate (or temperature variation with height) in atmospheric physics is obtained. A new source of plasma temperature gradient in a binary ion species mixture is found that is proportional to the concentration gradient and difference in average ionization states . Application to inertial-confinement-fusion implosions indicates a potentially strong effect in plastic (CH) ablators that is not modeled with mainline (single-fluid) simulations. An associated plasma thermodiffusion coefficient is derived, and charge-state diffusion in a single-species plasma is also predicted.

  7. Nonlinear Physics of Plasmas

    CERN Document Server

    Kono, Mitsuo

    2010-01-01

    A nonlinearity is one of the most important notions in modern physics. A plasma is rich in nonlinearities and provides a variety of behaviors inherent to instabilities, coherent wave structures and turbulence. The book covers the basic concepts and mathematical methods, necessary to comprehend nonlinear problems widely encountered in contemporary plasmas, but also in other fields of physics and current research on self-organized structures and magnetized plasma turbulence. The analyses make use of strongly nonlinear models solved by analytical techniques backed by extensive simulations and available experiments. The text is written for senior undergraduates, graduate students, lecturers and researchers in laboratory, space and fusion plasmas.

  8. Physics of Plasmas

    CERN Document Server

    Woods, Leslie Colin

    2003-01-01

    A short, self-sufficient introduction to the physics of plasma for beginners as well as researchers in a number of fields. The author looks at the dynamics and stability of magnetoplasma and discusses wave and transport in this medium. He also looks at such applications as fusion research using magnetic confinement of Deuterium plasma, solar physics with its plasma loops reaching high into the corona, sunspots and solar wind, engineering applications to metallurgy, MHD direct generation of electricity, and railguns, finally touching on the relatively new and difficult subject of dusty plasmas.

  9. Princeton Plasma Physics Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    This report discusses the following topics: principal parameters achieved in experimental devices fiscal year 1990; tokamak fusion test reactor; compact ignition tokamak; Princeton beta experiment- modification; current drive experiment-upgrade; international collaboration; x-ray laser studies; spacecraft glow experiment; plasma processing: deposition and etching of thin films; theoretical studies; tokamak modeling; international thermonuclear experimental reactor; engineering department; project planning and safety office; quality assurance and reliability; technology transfer; administrative operations; PPPL patent invention disclosures for fiscal year 1990; graduate education; plasma physics; graduate education: plasma science and technology; science education program; and Princeton Plasma Physics Laboratory reports fiscal year 1990.

  10. Solid expellant plasma generator

    Science.gov (United States)

    Stone, Nobie H. (Inventor); Poe, Garrett D. (Inventor); Rood, Robert (Inventor)

    2010-01-01

    An improved solid expellant plasma generator has been developed. The plasma generator includes a support housing, an electrode rod located in the central portion of the housing, and a mass of solid expellant material that surrounds the electrode rod within the support housing. The electrode rod and the solid expellant material are made of separate materials that are selected so that the electrode and the solid expellant material decompose at the same rate when the plasma generator is ignited. This maintains a point of discharge of the plasma at the interface between the electrode and the solid expellant material.

  11. Plasma processing for VLSI

    CERN Document Server

    Einspruch, Norman G

    1984-01-01

    VLSI Electronics: Microstructure Science, Volume 8: Plasma Processing for VLSI (Very Large Scale Integration) discusses the utilization of plasmas for general semiconductor processing. It also includes expositions on advanced deposition of materials for metallization, lithographic methods that use plasmas as exposure sources and for multiple resist patterning, and device structures made possible by anisotropic etching.This volume is divided into four sections. It begins with the history of plasma processing, a discussion of some of the early developments and trends for VLSI. The second section

  12. Plasma and particles

    Science.gov (United States)

    Špatenka, Petr; Vacková, Tat'ana; Nováček, Vojtěch; Jeníková, Zdenka

    2016-12-01

    Plasma has been proved as a standard industrial method for surface treatment of solid bulk materials. Recently plasma has also been used in connection with production, treatment and functionalization of powder and granulate materials. Functionalization was originally developed for hydrophylization of hydrophobic surfaces of particles made from various materials. An industrial scale device with a capacity of several hundreds of tons per year based on plasma treatment will be presented. As examples of the applications are given plasma treated polyethylene powder dispersed in the water; and very good adhesion of polymer powders to metals or glass, which is promising for development of new generation of thermoplastic composites.

  13. Single nucleotide polymorphisms in the growth hormone-insulin-like growth factor axis in straightbred and crossbred Angus, Brahman, and Romosinuano heifers: population genetic analyses and association of genotypes with reproductive phenotypes.

    Science.gov (United States)

    Luna-Nevarez, P; Rincon, G; Medrano, J F; Riley, D G; Chase, C C; Coleman, S W; Vanleeuwen, D M; DeAtley, K L; Islas-Trejo, A; Silver, G A; Thomas, M G

    2011-04-01

    The growth endocrine axis influences reproduction. The objectives of this study were to evaluate population genetic characteristics of SNP genotypes within genes of the GH-IGF axis in straightbred and crossbred Angus, Brahman, and Romosinuano heifers (n = 650) and to test the association of these genotypes with measures of reproduction. These objectives were achieved using 73 SNP within 7 genes on chromosome 5 and the pregnancy-associated plasma protein A2 (PAPP-A2) and GH-receptor genes, which map to chromosomes 16 and 20, respectively. The SNP were elucidated by resequencing conserved regions of each gene by using DNA from familial-unrelated cattle of a multibreed discovery population. A multiplex SNP assay yielded 59 biallelic SNP useful for evaluating genetic identity and distance. Specifically, the divergence of straightbred Brahman cattle was approximately 15.5% from 5 Bos taurus-influenced breed groups. In the straightbred groups used as a validation population, only 3 SNP had minor allele frequencies >10%. These SNP were in the genes PAPP-A2 (ss115492449-A/C and ss115492450-G/T within intron 10) and signal transducers and activators of transcription 2 (STAT2; ss252841035-A/G within the 5' untranslated region), and they met the conditions of Hardy-Weinberg equilibrium (P > 0.31). The other 56 SNP were useful for assigning each animal into ancestral clusters (n = 3 proportions) to account for population stratification in genotype to phenotype association analyses. The 2 SNP in the PAPP-A2 gene influenced (P < 0.05) traits indicative of first-calf heifer rebreeding (i.e., calving interval, days to calving, and pregnancy rate). A STAT2 SNP genotype (i.e., GG) × primary ancestral cluster interaction (P < 0.05) suggested heifers primarily of B. taurus ancestry had a reduction of approximately 16.4 ± 0.1% in calving interval and days to calving relative to heifers clustering primarily as Bos indicus ancestry. Even though additional research is needed to

  14. Screening for aneuploidies by maternal age, fetal nuchal translucency and maternal serum biochemistry at 11-13+6 gestational weeks

    Directory of Open Access Journals (Sweden)

    Karadžov-Orlić Nataša

    2012-01-01

    Full Text Available Introduction. Aneuploidies are the major cause of perinatal death and early psychophysical disorders. Objective. In this study, we analyzed detection and false-positive rates of screening for aneuploidies in the first trimester by the combination of maternal age, fetal nuchal translucency (NT thickness and maternal serum free beta-human chorionic gonadotrophin (β-hCG, and pregnancy-associated plasma protein-A (PAPP-A at 11-13+6 weeks of gestation, using the appropriate software developed by the Fetal Medicine Foundation. Methods. Our screening study for aneuploidies analyzed 4172 singleton pregnancies from January 2006 to December 2010. The sensitivities and false-positive rates using the combined aneuploidies determination for the risk cut-off of 1:275 were evaluated. Results. In the trisomy 21 pregnancies, the fetal NT was higher than 95th centile, in 72.8%, serum free b-hCG concentration it was above the 95th centile in 55% and serum PAPP-A was below the 5th centile in 47% of the cases. In the trisomy 18 and 13, the fetal NT was above 95th centile in 66.6% and 44.4% of the cases, respectively. The serum free b-hCG concentration was above the 95th centile in 0 and 10%, but serum PAPP-A was below 5th centile in 80.9% and 88.8% of pregnancies. In the trisomy 21 pregnancies the median free beta-hCG was 2.3 MoM and the median PAPP-A was 0.45 MoM. Chromosomal abnormalities were detected in 169 fetuses: trisomy 21 (97, Turner syndrome (19, trisomy 18 (28, trisomy 13 (11 and others (14. Detection rate of combined screening for aneuploides were 86.0% with false positive rate of 5.3% (mean age 33±4.9 years, >35 years in 35% of pregnancies. Conclusion. Our study suggests that the strategy of first-trimester combined screening of biochemical values and ultrasonographic parameters at 12 gestational weeks identifies higher percentage of aneuploidies with a lower false-positive rate than a single parameter strategy.

  15. Screening for trisomy 21 by maternal age, fetal nuchal translucency and maternal serum biochemistry at 11-14 weeks: a German multicenter study.

    Science.gov (United States)

    von Kaisenberg, C S; Gasiorek-Wiens, A; Bielicki, M; Bahlmann, F; Meyberg, H; Kossakiewicz, A; Pruggmayer, M; Kamin, G; Fritzer, E; Harris, C; Arnold, N

    2002-08-01

    To examine the effectiveness of screening for trisomy 21 by a combination of maternal age, fetal nuchal translucency (NT) thickness and maternal serum biochemistry using free beta-human chorionic gonadotropin (hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 11-14 weeks of gestation. This was a multicenter study of screening for trisomy 21 by a combination of maternal age, fetal NT and maternal serum free beta-hCG and PAPP-A at 11-14 weeks of gestation, using the methodology developed by the Fetal Medicine Foundation. The distribution of estimated risks for trisomy 21 was determined and the sensitivity and false-positive rate for a risk cut-off of 1 in 300 were calculated. In total, 3864 singleton pregnancies with live fetuses at 11-14 weeks were examined and the fetal NT and maternal serum free beta-hCG and PAPP-A were successfully measured in all cases. The median maternal age was 33 (range 15-46) years and, in 1271 (35.8%), the age was 35 years or more, the median gestation at screening was 12 (11-14) weeks and the median fetal crown-rump length was 64 (range 45-84) mm. The fetal NT was above the 95th centile in 73.7% (14 of 19) of trisomy 21 and in 4.8% (169 of 3505) of normal pregnancies. The estimated risk for trisomy 21 based on maternal age, fetal NT and maternal serum free beta-hCG and PAPP-A was 1 in 300 or greater in 6.6% (233 of 3505) of normal pregnancies, in 84.2% (16 of 19) of those with trisomy 21 and 88.9% (24 of 27) of those with other chromosomal defects. In Germany, the results of screening for chromosomal defects by measurement of fetal NT and maternal serum biochemistry, in centers with appropriately qualified sonographers, are similar to those reported in the UK using the same methodology.

  16. Screening for aneuploidies by maternal age, fetal nuchal translucency and maternal serum biochemistry at 11-13+6 gestational weeks.

    Science.gov (United States)

    Karadzov-Orlić, Natasa; Egić, Amira; Filimonović, Dejan; Marinković, Maja; Damnjanović-Pazin, Barbara; Milovanović, Zagorka; Joksić, Ivana; Branković, Snezana; Lukić, Relja; Mandić, Vesna; Cerović, Nikola; Mojović, Donka; Plamenac, Sanja; Stanković, Minja; Maglić, Dragana; Mikovć, Zeljko

    2012-01-01

    Aneuploidies are the major cause of perinatal death and early psychophysical disorders. In this study, we analyzed detection and false-positive rates of screening for aneuploidies in the first trimester by the combination of maternal age, fetal nuchal translucency (NT) thickness and maternal serum free beta-human chorionic gonadotrophin (beta-hCG), and pregnancy-associated plasma protein-A (PAPP-A) at 11-13+6 weeks of gestation, using the appropriate software developed by the Fetal Medicine Foundation. Our screening study for aneuploidies analyzed 4172 singleton pregnancies from January 2006 to December 2010. The sensitivities and false-positive rates using the combined aneuploidies determination for the risk cut-off of 1:275 were evaluated. In the trisomy 21 pregnancies, the fetal NT was higher than 95th centile, in 72.8%, serum free b-hCG concentration it was above the 95th centile in 55% and serum PAPP-A was below the 5th centile in 47% of the cases. In the trisomy 18 and 13, the fetal NT was above 95th centile in 66.6% and 44.4% of the cases, respectively.The serum free b-hCG concentration was above the 95th centile in 0 and 10%, but serum PAPP-A was below 5th centile in 80.9% and 88.8% of pregnancies. In the trisomy 21 pregnancies the median free beta-hCG was 2.3 MoM and the median PAPP-A was 0.45 MoM. Chromosomal abnormalities were detected in 169 fetuses: trisomy 21 (97), Turner syndrome (19), trisomy 18 (28), trisomy 13 (11) and others (14). Detection rate of combined screening for aneuploides were 86.0% with false positive rate of 5.3% (mean age 33 +/- 4.9 years, > 35 years in 35% of pregnancies). Our study suggests that the strategy of first-trimester combined screening of biochemical values and ultrasonographic parameters at 12 gestational weeks identifies higher percentage of aneuploidies with a lower false-positive rate than a single parameter strategy.

  17. One-stop clinic for assessment of risk for trisomy 21 at 11-14 weeks: a prospective study of 15 030 pregnancies.

    Science.gov (United States)

    Bindra, R; Heath, V; Liao, A; Spencer, K; Nicolaides, K H

    2002-09-01

    To evaluate the performance of a one-stop clinic for assessment of risk (OSCAR) for trisomy 21 by a combination of maternal age, fetal nuchal translucency (NT) thickness and maternal serum free beta-human chorionic gonadotropin (hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 11-14 weeks of gestation. Screening for trisomy 21 was carried out by OSCAR in 15 030 singleton pregnancies with live fetuses at 11-14 weeks. The estimated risk for trisomy 21 was calculated, and the women were counseled regarding this risk and the option of invasive testing or expectant management. Follow-up of the outcome of all pregnancies was carried out. The detection and false-positive rates for different risk cut-offs were calculated. Fetal NT and maternal serum free beta-hCG and PAPP-A were successfully measured in all cases. Pregnancy outcome, including karyotype results or the birth of a phenotypically normal baby, was obtained from 14 383 cases. The median maternal age of these cases was 34 (range 15-49) years and in 6768 (47.1%) the age was 35 years or greater. The median gestation at screening was 12 (range 11-14) weeks and the median fetal crown-rump length was 64 (range 45-84) mm. The estimated risk for trisomy 21 based on maternal age, fetal NT and maternal serum free beta-hCG and PAPP-A was 1 in 300 or greater in 6.8% (967 of 14 240) normal pregnancies, in 91.5% (75 of 82) of those with trisomy 21 and in 88.5% (54 of 61) of those with other chromosomal defects. For a fixed false-positive rate of 5% the respective detection rates of screening for trisomy 21 by maternal age alone, maternal age and serum free beta-hCG and PAPP-A, maternal age and fetal NT, and by maternal age, fetal NT and maternal serum biochemistry were 30.5%, 59.8%, 79.3% and 90.2%, respectively. Screening for trisomy 21 by a combination of maternal age, fetal NT and maternal serum biochemistry at 11-14 weeks can be provided in an OSCAR setting and is associated with a detection rate of about 90

  18. Chemiluminescence enzyme immunoassay using ProteinA-bacterial magnetite complex

    Science.gov (United States)

    Matsunaga, Tadashi; Sato, Rika; Kamiya, Shinji; Tanaka, Tsuyosi; Takeyama, Haruko

    1999-04-01

    Bacterial magnetic particles (BMPs) which have ProteinA expressed on their surface were constructed using magA which is a key gene in BMP biosynthesis in the magnetic bacterium Magnetospirillum sp. AMB-1. Homogenous chemiluminescence enzyme immunoassay using antibody bound ProteinA-BMP complexes was developed for detection of human IgG. A good correlation between the luminescence yield and the concentration of human IgG was obtained in the range of 1-10 3 ng/ml.

  19. Ultracold neutral plasmas

    Science.gov (United States)

    Lyon, M.; Rolston, S. L.

    2017-01-01

    By photoionizing samples of laser-cooled atoms with laser light tuned just above the ionization limit, plasmas can be created with electron and ion temperatures below 10 K. These ultracold neutral plasmas have extended the temperature bounds of plasma physics by two orders of magnitude. Table-top experiments, using many of the tools from atomic physics, allow for the study of plasma phenomena in this new regime with independent control over the density and temperature of the plasma through the excitation process. Characteristic of these systems is an inhomogeneous density profile, inherited from the density distribution of the laser-cooled neutral atom sample. Most work has dealt with unconfined plasmas in vacuum, which expand outward at velocities of order 100 m/s, governed by electron pressure, and with lifetimes of order 100 μs, limited by stray electric fields. Using detection of charged particles and optical detection techniques, a wide variety of properties and phenomena have been observed, including expansion dynamics, collective excitations in both the electrons and ions, and collisional properties. Through three-body recombination collisions, the plasmas rapidly form Rydberg atoms, and clouds of cold Rydberg atoms have been observed to spontaneously avalanche ionize to form plasmas. Of particular interest is the possibility of the formation of strongly coupled plasmas, where Coulomb forces dominate thermal motion and correlations become important. The strongest impediment to strong coupling is disorder-induced heating, a process in which Coulomb energy from an initially disordered sample is converted into thermal energy. This restricts electrons to a weakly coupled regime and leaves the ions barely within the strongly coupled regime. This review will give an overview of the field of ultracold neutral plasmas, from its inception in 1999 to current work, including efforts to increase strong coupling and effects on plasma properties due to strong coupling.

  20. Plasma Physics An Introduction to Laboratory, Space, and Fusion Plasmas

    CERN Document Server

    Piel, Alexander

    2010-01-01

    Plasma Physics gives a comprehensive introduction to the basic processes in plasmas and demonstrates that the same fundamental concepts describe cold gas-discharge plasmas, space plasmas, and hot fusion plasmas. Starting from particle drifts in magnetic fields, the principles of magnetic confinement fusion are explained and compared with laser fusion. Collective processes are discussed in terms of plasma waves and instabilities. The concepts of plasma description by magnetohydrodynamics, kinetic theory, and particle simulation are stepwise introduced. Space charge effects in sheath regions, double layers and plasma diodes are given the necessary attention. The new fundamental mechanisms of dusty plasmas are explored and integrated into the framework of conventional plasmas. The book concludes with a brief introduction to plasma discharges. Written by an internationally renowned researcher in experimental plasma physics, the text keeps the mathematical apparatus simple and emphasizes the underlying concepts. T...

  1. Maternal serum biochemistry at 11-13(+6) weeks in relation to the presence or absence of the fetal nasal bone on ultrasonography in chromosomally abnormal fetuses: an updated analysis of integrated ultrasound and biochemical screening.

    Science.gov (United States)

    Cicero, Simona; Spencer, Kevin; Avgidou, Kyriaki; Faiola, Stefano; Nicolaides, Kypros H

    2005-11-01

    Screening for trisomy 21 by a combination of maternal age, fetal nuchal translucency (NT) thickness and maternal serum free beta-hCG and pregnancy associated plasma protein-A (PAPP-A) at 11-13(+6) weeks of gestation is associated with a detection rate of 90%, for a false-positive rate of 5%. Recent evidence suggests that in about 70% of fetuses with trisomy 21 the nasal bone is not visible at the 11-13(+6) week scan and that the frequency of absence of nasal bone differs in different ethnic groups. In addition, there is a relationship between absent nasal bone and nuchal translucency thickness. In a preliminary study we showed that while PAPP-A levels were lower and free beta-hCG levels were higher in trisomy 21 fetuses with an absent nasal bone, this difference was not statistically different. In fetuses with trisomy 13 and trisomy 18, there is also a high (57 and 67%) incidence of an absent nasal bone. The aim of this present study was to extend our examination of whether the level of maternal serum biochemical markers is independent of the presence or absence of the nasal bone in cases with trisomy 21 and to ascertain if any differences exist in cases with trisomies 13 and 18. This study data comprised 100 trisomy 21 singleton pregnancies at 11-13(+6) weeks of gestation from our previous study and an additional 42 cases analysed as part of routine OSCAR screening. A total of 34 cases with trisomy 18 and 12 cases with trisomy 13 were also available. Ultrasound examination was carried out for measurement of fetal NT and assessment of the presence or absence of the fetal nasal bone. Maternal serum free beta-hCG and PAPP-A were measured using the Kryptor rapid random access immunoassay analyser (Brahms Diagnostica AG, Berlin). The distribution of maternal serum free beta-hCG and PAPP-A in chromosomally abnormal fetuses with absent and present nasal bone was examined. The nasal bone was absent in 29 and present in 13 of the new trisomy 21 cases and in 98 (69%) and 44

  2. Comparison of protein A affinity sorbents III. Life time study.

    Science.gov (United States)

    Hahn, Rainer; Shimahara, Kazumichi; Steindl, Franz; Jungbauer, Alois

    2006-01-13

    Protein A affinity chromatography is a popular purification method for immunoglobulins applied at various scales, ranging from micro-tube up to 1000l column format. Three novel high capacity protein A affinity chromatography media have been subjected to a lifetime study using 50 consecutive purification cycles of a cell culture supernatant (CCS) containing a monoclonal antibody. Chromatographic conditions followed protocols used in industrial antibody processing, including stripping and cleaning-in-place of the resins. For all three media, no significant loss of purification performance (measured by sodium dodecylsulfate polyacrylamide gel electrophoresis and analytical size-exclusion chromatography (SEC)) could be observed over 50 cycles. Eluate samples were analyzed for leaked protein A and host cell protein (HCP) content. MabSelect SuRe, the first protein A affinity medium compatible with alkaline regeneration conditions, exhibited the lowest leakage levels, in the range of 1-3 ppm. For the media MabSelect Xtra and ProSep-vA Ultra, leakage levels were in the range of 30-40 ppm. Host cell protein content of eluates from MabSelect Xtra and SuRe were between 300 and 700 ppm, whereas for ProSep-vA Ultra 3000-4000 ppm was achieved.

  3. Structural characterisation of human proteinosis surfactant protein A

    DEFF Research Database (Denmark)

    Leth-Larsen, Rikke; Holmskov, U; Højrup, P

    2000-01-01

    Human surfactant protein-A (SP-A) has been purified from a proteinosis patient and characterised by a combination of automated Edman degradation and mass spectrometry. The complete protein sequence was characterised. The major part of SP-A was shown to consist of SP-A2 gene product, and only...

  4. EDITORIAL: Plasma jets and plasma bullets Plasma jets and plasma bullets

    Science.gov (United States)

    Kong, M. G.; Ganguly, B. N.; Hicks, R. F.

    2012-06-01

    Plasma plumes, or plasma jets, belong to a large family of gas discharges whereby the discharge plasma is extended beyond the plasma generation region into the surrounding ambience, either by a field (e.g. electromagnetic, convective gas flow, or shock wave) or a gradient of a directionless physical quantity (e.g. particle density, pressure, or temperature). This physical extension of a plasma plume gives rise to a strong interaction with its surrounding environment, and the interaction alters the properties of both the plasma and the environment, often in a nonlinear and dynamic fashion. The plasma is therefore not confined by defined physical walls, thus extending opportunities for material treatment applications as well as bringing in new challenges in science and technology associated with complex open-boundary problems. Some of the most common examples may be found in dense plasmas with very high dissipation of externally supplied energy (e.g. in electrical, optical or thermal forms) and often in or close to thermal equilibrium. For these dense plasmas, their characteristics are determined predominantly by strong physical forces of different fields, such as electrical, magnetic, thermal, shock wave, and their nonlinear interactions [1]. Common to these dense plasma plumes are significant macroscopic plasma movement and considerable decomposition of solid materials (e.g. vaporization). Their applications are numerous and include detection of elemental traces, synthesis of high-temperature materials and welding, laser--plasma interactions, and relativistic jets in particle accelerators and in space [2]-[4]. Scientific challenges in the understanding of plasma jets are exciting and multidisciplinary, involving interweaving transitions of all four states of matter, and their technological applications are wide-ranging and growing rapidly. Using the Web of Science database, a search for journal papers on non-fusion plasma jets reveals that a long initial phase up

  5. [Acute plasma cell leukemia].

    Science.gov (United States)

    Monsalbe, V; Domíngues, C; Roa, I; Busel, D; González, S

    1989-01-01

    Plasma Cell Leukemia is a very rare form of plasmocytic dyscrasia, whose clinical and pathological characteristics warrant its recognition as a distinct subentity. We report the case of a 60 years old man who presented a rapidly fatal acute plasma cell leukemia, with multiple osteolytic lesions, hipercalcemia, renal and cardiac failure.

  6. Plasma polarization spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, Takashi [Department of Engineering Physics and Mechanics, Graduate School of Engineering, Kyoto University, Kyoto (Japan)

    2000-03-01

    Polarization of radiation emitted from a plasma reflects the anisotropic properties of the plasma, especially the angular anisotropic distribution of electron velocities. Polarization has been observed on impurity ion lines from the WT-3 tokamak and the GAMMA-10 tandem mirror machines. The soft x-ray laser line from the neonlike germanium was also found polarized. (author)

  7. Plasma polarization spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Iwamae, Atsushi; Inoue, Takeru; Tanaka, Akihiro; Kawakami, Kazuki; Fujimoto, Takashi [Kyoto Univ., Dept. of Engineering Physics, Kyoto (Japan)

    2000-03-01

    Polarization of radiation emitted from plasma reflects the anisotropic properties of the plasma, especially the angular isotropic distribution of electron velocities. Polarization has been observed on impurity ion lines from the WT-3 tokamak and GAMMA 10 tandem mirror device. (author)

  8. Atoms in dense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    More, R.M.

    1986-01-01

    Recent experiments with high-power pulsed lasers have strongly encouraged the development of improved theoretical understanding of highly charged ions in a dense plasma environment. This work examines the theory of dense plasmas with emphasis on general rules which govern matter at extreme high temperature and density. 106 refs., 23 figs.

  9. Plasma etching an introduction

    CERN Document Server

    Manos, Dennis M

    1989-01-01

    Plasma etching plays an essential role in microelectronic circuit manufacturing. Suitable for researchers, process engineers, and graduate students, this book introduces the basic physics and chemistry of electrical discharges and relates them to plasma etching mechanisms. Throughout the volume the authors offer practical examples of process chemistry, equipment design, and production methods.

  10. Modelling of Complex Plasmas

    NARCIS (Netherlands)

    Akdim, M.R. (Mohamed Reda)

    2003-01-01

    Nowadays plasmas are used for various applications such as the fabrication of silicon solar cells, integrated circuits, coatings and dental cleaning. In the case of a processing plasma, e.g. for the fabrication of amorphous silicon solar cells, a mixture of silane and hydrogen gas is injected in a r

  11. "Angular" plasma cell cheilitis.

    Science.gov (United States)

    da Cunha Filho, Roberto Rheingantz; Tochetto, Lucas Baldissera; Tochetto, Bruno Baldissera; de Almeida, Hiram Larangeira; Lorencette, Nádia Aparecida; Netto, José Fillus

    2014-03-17

    Plasma cell cheilitis is an extremely rare disease, characterized by erythematous-violaceous, ulcerated and asymptomatic plaques, which evolve slowly. The histological characteristics include dermal infiltrate composed of mature plasmocytes. We report a case of Plasma cell angular cheilitis in a 58-year-old male, localized in the lateral oral commissure.

  12. "Angular" plasma cell cheilitis

    OpenAIRE

    da Cunha Filho, Roberto Rheingantz; Tochetto, Lucas Baldissera; Tochetto, Bruno Baldissera; de Almeida Jr, Hiram Larangeira; Lorencette, Nadia Aparecida; Netto, Jose Fillus

    2014-01-01

    Plasma cell cheilitis is an extremely rare disease, characterized by erythematous-violaceous, ulcerated and asymptomatic plaques, which evolve slowly. The histological characteristics include dermal infiltrate composed of mature plasmocytes. We report a case of Plasma cell angular cheilitis in a 58-year-old male, localized in the lateral oral commissure.

  13. Introduction to Plasma Spectroscopy

    CERN Document Server

    Kunze, H-J

    2009-01-01

    Based on lectures given at the Ruhr-University of Bochum for graduate students and postgraduates starting in plasma physics as well as from low- to high-density hot plasmas, this book introduces basic ideas and fundamental concepts and typical instrumentation from the X-ray to the infrared spectral regions

  14. Innovations in plasma sensors

    Science.gov (United States)

    Zurbuchen, Thomas H.; Gershman, Daniel J.

    2016-04-01

    During the history of space exploration, ever improving instruments have continued to enable new measurements and discoveries. Focusing on plasma sensors, we examine the processes by which such new instrument innovations have occurred over the past decades. Due to risk intolerance prevalent in many NASA space missions, innovations in plasma instrumentation occur primarily when heritage systems fail to meet science requirements, functional requirements as part of its space platform, or design constraints. We will review such innovation triggers in the context of the design literature and with the help of two case studies, the Fast Imaging Plasma Spectrometer on MErcury Surface, Space ENvironment, GEochemistry, and Ranging and the Fast Plasma Investigation on Magnetosphere Multiscale. We will then discuss the anticipated needs for new plasma instrument innovations to enable the science program of the next decade.

  15. Wakes in inhomogeneous plasmas

    CERN Document Server

    Kompaneets, Roman; Nosenko, Vladimir; Morfill, Gregor E

    2014-01-01

    The Debye shielding of a charge immersed in a flowing plasma is an old classic problem in plasma physics. It has been given renewed attention in the last two decades in view of experiments with complex plasmas, where charged dust particles are often levitated in a region with strong ion flow. Efforts to describe the shielding of the dust particles in such conditions have been focused on the homogeneous plasma approximation, which ignores the substantial inhomogeneity of the levitation region. We address the role of the plasma inhomogeneity by rigorously calculating the point charge potential in the collisionless Bohm sheath. We demonstrate that the inhomogeneity can dramatically modify the wake, making it non-oscillatory and weaker.

  16. Basic plasma physics

    CERN Document Server

    Ghosh, Basudev

    2014-01-01

    Basic Plasma Physics is designed to serve as an introductory compact textbook for advanced undergraduate, postgraduate and research students taking plasma physics as one of their subject of study for the first time. It covers the current syllabus of plasma physics offered by the most universities and technical institutions. The book requires no background in plasma physics but only elementary knowledge of basic physics and mathematics. Emphasis has been given on the analytical approach. Topics are developed from first principle so that the students can learn through self-study. One chapter has been devoted to describe some practical aspects of plasma physics. Each chapter contains a good number of solved and unsolved problems and a variety of review questions, mostly taken from recent examination papers. Some classroom experiments described in the book will surely help students as well as instructors.

  17. Microphysics of cosmic plasmas

    CERN Document Server

    Bykov, Andrei; Cargill, Peter; Dendy, Richard; Wit, Thierry; Raymond, John

    2014-01-01

    This title presents a review of the detailed aspects of the physical processes that underlie the observed properties, structures and dynamics of cosmic plasmas. An assessment of the status of understanding of microscale processes in all astrophysical collisionless plasmas is provided. The topics discussed include  turbulence in astrophysical and solar system plasmas as a phenomenological description of their dynamic properties on all scales; observational, theoretical and modelling aspects of collisionless magnetic reconnection; the formation and dynamics of shock waves; and a review and assessment of microprocesses, such as the hierarchy of plasma instabilities, non-local and non-diffusive transport processes and ionisation and radiation processes.  In addition, some of the lessons that have been learned from the extensive existing knowledge of laboratory plasmas as applied to astrophysical problems are also covered.   This volume is aimed at graduate students and researchers active in the areas of cosmi...

  18. SUPERFAST THERMALIZATION OF PLASMA

    Science.gov (United States)

    Chang, C.C.

    1962-06-12

    A method is given for the superfast thermalization of plasma by shock conversion of the kinetic energy stored in rotating plasma rings or plasmoids colliding at near supersonic speeds in a containment field to heat energy in the resultant confined plasma mass. The method includes means for generating rotating plasmoids at the opposite ends of a Pyrotron or Astron containment field. The plasmoids are magnetically accelerated towards each other into the opposite ends of time containment field. During acceleration of the plasmoids toward the center of the containment field, the intensity of the field is sequentially increased to adiabatically compress the plasmoids and increase the plasma energy. The plasmoids hence collide with a violent shock at the eenter of the containment field, causing the substantial kinetic energy stored in the plasmoids to be converted to heat in the resultant plasma mass. (AEC)

  19. Plasma polymerization by Softplasma

    DEFF Research Database (Denmark)

    Jiang, J.; Wu, Zhenning; Benter, Maike

    2008-01-01

    as reactive splvent (as shown in Figure 1). 1] H. Biederman, in Plasma Polymer Films. (ed.) H. Biederman. Imperial College Press, Singapore, 13-24 ~OO~· '. , [2] R. d'Agostino et.a!. in Plasma Depd~itiqn, 'Treatment, and Etching ofPolymers. (ed.) R. d'Agostino, Academic Press, U.S. (1990). [3] F. F. Shi......In the late 19th century, the first depositions - known today as plasma polymers, were reported. In the last century, more and more research has been put into plasma polymers. Many different deposition systems have been developed. [1, 2] Shi F. F. broadly classified them into internal electrode......, external electrode, and electrodeless microwave or high frequency reactors. [3] Softplasma™ is an internal electrode plasma setup powered by low frequenc~ gower supply. It was developed in late 90s for surface treatment of silicone rubber. [ ]- 5] It is a low pressure, low electron density, 3D homogenous...

  20. Gingival plasma cell granuloma

    Directory of Open Access Journals (Sweden)

    Phadnaik Mangesh

    2010-01-01

    Full Text Available Plasma cell granuloma is a rare reactive lesion composed of polyclonal plasma cells. It manifests primarily in the lungs, but may occur in various other anatomic locations like the oral cavity. Intraoral plasma cell granulomas involving the tongue, lip, oral mucosa and gingiva have been reported in the past. This case presents a 54-year-old female with chronic periodontitis and mandibular anterior gingival overgrowth treated by Phase I therapy (scaling and root planing and excisional biopsy. Histological examination revealed inflammatory cell infiltrate containing sheets of plasma cells. Immunohistochemistry for kappa and lambda light chains showed a polyclonal staining pattern confirming a diagnosis of plasma cell granuloma. This case highlights the need to biopsy for unusual lesions to rule out potential neoplasms.

  1. Helical plasma thruster

    Energy Technology Data Exchange (ETDEWEB)

    Beklemishev, A. D., E-mail: bekl@bk.ru [Budker Institute of Nuclear Physics SB RAS, Novosibirsk (Russian Federation)

    2015-10-15

    A new scheme of plasma thruster is proposed. It is based on axial acceleration of rotating magnetized plasmas in magnetic field with helical corrugation. The idea is that the propellant ionization zone can be placed into the local magnetic well, so that initially the ions are trapped. The E × B rotation is provided by an applied radial electric field that makes the setup similar to a magnetron discharge. Then, from the rotating plasma viewpoint, the magnetic wells of the helically corrugated field look like axially moving mirror traps. Specific shaping of the corrugation can allow continuous acceleration of trapped plasma ions along the magnetic field by diamagnetic forces. The accelerated propellant is expelled through the expanding field of magnetic nozzle. By features of the acceleration principle, the helical plasma thruster may operate at high energy densities but requires a rather high axial magnetic field, which places it in the same class as the VASIMR{sup ®} rocket engine.

  2. Diagnostics of Nanodusty Plasma

    Science.gov (United States)

    Greiner, Franko; Groth, Sebastian; Tadsen, Bejamin; Piel, Alexander

    2015-11-01

    The diagnostic of nanodusty plasmas, i.e. plasmas including nano-sized dust particles, is a challenging task. For both, the diagnostic of the nanodusty plasma itself, and the in-situ diagnostic of the nanoparticles, no standard diagnostic exist. Nanodust particle size and density can be estimated using light scattering techniques, namely kinetic Mie ellipsometry and extinction measurements. The charge of the nanoparticles can be estimated from the analysis of dust density waves (DDW). Parameters like the electron density, which give information about the plasma itself, may be deduced from the DDW analysis. We present detailed investigations on nanodust in a reactive Argon-Acetylene plasma created in an rf-driven parallel plate reactor at low pressure using the above mentioned portfolio of diagnostic. Funded by DFG under contract SFB TR-24/A2.

  3. Solar system plasma waves

    Science.gov (United States)

    Gurnett, Donald A.

    1995-01-01

    An overview is given of spacecraft observations of plasma waves in the solar system. In situ measurements of plasma phenomena have now been obtained at all of the planets except Mercury and Pluto, and in the interplanetary medium at heliocentric radial distances ranging from 0.29 to 58 AU. To illustrate the range of phenomena involved, we discuss plasma waves in three regions of physical interest: (1) planetary radiation belts, (2) planetary auroral acceleration regions and (3) the solar wind. In each region we describe examples of plasma waves that are of some importance, either due to the role they play in determining the physical properties of the plasma, or to the unique mechanism involved in their generation.

  4. Electronegative Plasma Instabilities in Industrial Pulsed Plasmas

    Science.gov (United States)

    Pribyl, Patrick; Hansen, Anders; Gekelman, Walter

    2016-10-01

    Electronegative gases that are important for industrial etch processes have a series of instabilities that occur at process relevant conditions. These have been studied since the 1990s, but are becoming a much more important today as plasma reactors are being pushed to produce ever finer features, and tight control of the etch process is becoming crucial. The experiments are being done in a plasma etch tool that closely simulates a working industrial device. ICP coils in different configurations are driven by a pulsed RF generators operating at 2-5 MHz. A computer controlled automated probe drive can access a volume above the substrate. The probe can be a Langmuir probe, a ``Bdot'' probe, or an emissive probe the latter used for more accurate determination of plasma potential. A microwave interferometer is available to measure line-averaged electron density. The negative ion instability is triggered depending upon the gas mix (Ar,SF6) , pressure and RF power. The instability can be ``burned through'' by rapidly pulsing the RF power. In this study we present measurements of plasma current and density distribution over the wafer before, after and during the rapid onset of the instability. Work suported by NSF-GOALI Award and done at the BAPSF.

  5. Nonthermal plasma chemistry and physics

    CERN Document Server

    Meichsner, Jurgen; Schneider, Ralf; Wagner, Hans-Erich

    2013-01-01

    In addition to introducing the basics of plasma physics, Nonthermal Plasma Chemistry and Physics is a comprehensive presentation of recent developments in the rapidly growing field of nonthermal plasma chemistry. The book offers a detailed discussion of the fundamentals of plasma chemical reactions and modeling, nonthermal plasma sources, relevant diagnostic techniques, and selected applications.Elucidating interconnections and trends, the book focuses on basic principles and illustrations across a broad field of applications. Expert contributors address environmental aspects of plasma chemist

  6. Plasma physics an introduction to laboratory, space, and fusion plasmas

    CERN Document Server

    Piel, Alexander

    2017-01-01

    The enlarged new edition of this textbook provides a comprehensive introduction to the basic processes in plasmas and demonstrates that the same fundamental concepts describe cold gas-discharge plasmas, space plasmas, and hot fusion plasmas. Starting from particle drifts in magnetic fields, the principles of magnetic confinement fusion are explained and compared with laser fusion. Collective processes are discussed in terms of plasma waves and instabilities. The concepts of plasma description by magnetohydrodynamics, kinetic theory, and particle simulation are stepwise introduced. Space charge effects in sheath regions, double layers and plasma diodes are given the necessary attention. The novel fundamental mechanisms of dusty plasmas are explored and integrated into the framework of conventional plasmas. The book concludes with a concise description of modern plasma discharges. Written by an internationally renowned researcher in experimental plasma physics, the text keeps the mathematical apparatus simple a...

  7. Urine and plasma propranolol.

    Science.gov (United States)

    Andreasen, F; Jakobsen, P; Kornerup, H J; Pedersen, E B; Pedersen, O L

    1983-01-01

    Eight hypertensive patients who had been followed in an outpatient clinic during long-term therapy with propranolol (40 to 160 mg twice daily) were studied during a 24-hr stay in the ward. The usual oral dose was given and the total and free plasma concentrations were determined during the 24 hr and the urinary excretion of unchanged drug was measured. Average free plasma concentration of propranolol (y free) was calculated from: y free = Excreted propranolol (ng/24 hr)/Creatinine clearance (ml/24 hr). There was a significant relationship between log y free and average free plasma concentration (means free) determined from the directly measured plasma concentration curve: log y free = 0.0743 means free - 0.0466 (r = 0.98, P less than 0.001). In another group of propranolol-treated hypertensive patients there was a significant positive relationship between orosomucoid concentration and reciprocal of the free propranolol fraction in plasma. From this relationship the average total drug concentration (y total) was calculated from y free; there was a significant correlation with directly measured total plasma level: log y total = 0.0038 . means total + 1.0895 (r = 0.91, P less than 0.001). It is suggested that individually determined values of y free below 30 ng/ml and y total below 400 ng/ml (the concentration range studied) can be used to calculate the average mean 24-hr free and total plasma concentrations.

  8. Dense Hypervelocity Plasma Jets

    Science.gov (United States)

    Case, Andrew; Witherspoon, F. Douglas; Messer, Sarah; Bomgardner, Richard; Phillips, Michael; van Doren, David; Elton, Raymond; Uzun-Kaymak, Ilker

    2007-11-01

    We are developing high velocity dense plasma jets for fusion and HEDP applications. Traditional coaxial plasma accelerators suffer from the blow-by instability which limits the mass accelerated to high velocity. In the current design blow-by is delayed by a combination of electrode shaping and use of a tailored plasma armature created by injection of a high density plasma at a few eV generated by arrays of capillary discharges or sparkgaps. Experimental data will be presented for a complete 32 injector gun system built for driving rotation in the Maryland MCX experiment, including data on penetration of the plasma jet through a magnetic field. We present spectroscopic measurements of plasma velocity, temperature, and density, as well as total momentum measured using a ballistic pendulum. Measurements are in agreement with each other and with time of flight data from photodiodes and a multichannel PMT. Plasma density is above 10^15 cm-3, velocities range up to about 100 km/s. Preliminary results from a quadrature heterodyne HeNe interferometer are consistent with these results.

  9. Plasma Science Committee (PLSC)

    Science.gov (United States)

    1990-12-01

    The Plasma Science Committee (PLSC) is a standing committee under the auspices of the Board on Physics and Astronomy, Commission on Physical Sciences, Mathematics, and Applications of the National Academy of Sciences - National Research Council. Plasma sciences represent a broad and diverse field. The PLSC has accepted the responsibility of monitoring the continuing development and assessing the general health of the field as whole. Although select advisory bodies have been created to address specific issues that affect plasma science, such as the Fusion Policy Advisory Committee (FPAC), the PLSC provides a focus for the plasma science community that is unique and essential. The membership of the PLSC is drawn from research laboratories in universities, industry, and government. Areas of expertise on the committee include accelerators and beams, space physics, astrophysics, computational physics and applied mathematics, fusion plasmas, fundamental experiments and theory, radiation sources, low temperature plasmas, and plasma-surface interactions. The PLSC is well prepared to respond to requests for studies on specific issues.

  10. Influence of plasma density and plasma sheath dynamics on the ion implantation by plasma immersion technique

    OpenAIRE

    Ensinger, Wolfgang

    1996-01-01

    Influence of plasma density and plasma sheath dynamics on the ion implantation by plasma immersion technique / B. Rauschenbach ... - In: Nuclear instruments and methods in physics research. B. 113. 1996. S. 266-269

  11. Stirring Unmagnetized Plasma

    CERN Document Server

    Collins, C; Wallace, J; Jara-Almonte, J; Reese, I; Zweibel, E; Forest, C B; 10.1103/PhysRevLett.108.115001

    2012-01-01

    A new concept for spinning unmagnetized plasma is demonstrated experimentally. Plasma is confined by an axisymmetric multi-cusp magnetic field and biased cathodes are used to drive currents and impart a torque in the magnetized edge. Measurements show that flow viscously couples momentum from the magnetized edge (where the plasma viscosity is small) into the unmagnetized core (where the viscosity is large) and that the core rotates as a solid body. To be effective, collisional viscosity must overcome the ion-neutral drag due to charge exchange collisions.

  12. Optical plasma microelectronic devices

    CERN Document Server

    Forati, Ebrahim; Dill, Thyler; Sievenpiper, Dan

    2015-01-01

    The semiconductor channel in conventional microelectronic devices was successfully replaced with an optically triggered gas plasma channel. The combination of DC and laser-induced gas ionizations controls the conductivity of the channel, enabling us to realize different electronic devices such as transistors, switches, modulators, etc. A special micro-scale metasurface was used to enhance the laser-gas interaction, as well as combining it with DC ionization properly. Optical plasma devices benefit form the advantages of plasma/vacuum electronic devices while preserving most of the integrablity of semiconductor based devices.

  13. Radiofrequency power in plasmas

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    This document includes the various communications that were presented at the 11th topical conference on radio frequency power in plasmas which took place in Palm Springs in May 1995. It includes current diffusion studies to assess the non-inductive current deposition profiles, experiments for plasma to reach quickly an equilibrium state, and modelling of electrons in plasma. Some comparison studies also reveal the efficiency of the Quasi-Optical Grill antenna for reactor applications. Finally, a scenario for efficient mode conversion heating in the ion cyclotron range of frequency is presented. Separate abstracts were prepared for the 6 papers in this volume. (TEC).

  14. Plasma Diagnostics and Plasma-Surface Interactions in Inductively Coupled Plasmas

    OpenAIRE

    Titus, Monica Joy

    2010-01-01

    The semiconductor industry's continued trend of manufacturing device features on the nanometer scale requires increased plasma processing control and improved understanding of plasma characteristics and plasma-surface interactions. This dissertation presents a series of experimental results for focus studies conducted in an inductively coupled plasma (ICP) system. First novel "on-wafer" diagnostic tools are characterized and related to plasma characteristics. Second, plasma-polymer interactio...

  15. Host cell protein adsorption characteristics during protein A chromatography.

    Science.gov (United States)

    Tarrant, Richard D R; Velez-Suberbie, M Lourdes; Tait, Andrew S; Smales, C Mark; Bracewell, Daniel G

    2012-07-01

    Protein A chromatography is a critical and 'gold-standard' step in the purification of monoclonal antibody (mAb) products. Its ability to remove >98% of impurities in a single step alleviates the burden on subsequent process steps and facilitates the implementation of platform processes, with a minimal number of chromatographic steps. Here, we have evaluated four commercially available protein A chromatography matrices in terms of their ability to remove host cell proteins (HCPs), a complex group of process related impurities that must be removed to minimal levels. SELDI-TOF MS was used as a screening tool to generate an impurity profile fingerprint for each resin and indicated a number of residual impurities present following protein A chromatography, agreeing with HCP ELISA. Although many of these were observed for all matrices there was a significantly elevated level of impurity binding associated with the resin based on controlled pore glass under standard conditions. Use of null cell line supernatant with and without spiked purified mAb demonstrated the interaction of HCPs to be not only with the resin back-bone but also with the bound mAb. A null cell line column overload and sample enrichment method before 2D-PAGE was then used to determine individual components associated with resin back-bone adsorption. The methods shown allow for a critical analysis of HCP removal during protein A chromatography. Taken together they provide the necessary process understanding to allow process engineers to identify rational approaches for the removal of prominent HCPs.

  16. Gingival plasma cell granuloma

    Directory of Open Access Journals (Sweden)

    Amitkumar B Pandav

    2012-01-01

    Full Text Available Plasma cell granuloma, also known as inflammatory pseudotumor is a tumor-like lesion that manifests primarily in the lungs. But it may occur in various other anatomic locations like orbit, head and neck, liver and rarely in the oral cavity. We here report an exceedingly rare case of gingival plasma cell granuloma in a 58 year old woman who presented with upper gingival polypoidal growth. The histopathological examination revealed a mass composed of proliferation of benign spindle mesenchymal cells in a loose myxoid and fibrocollagenous stroma along with dense infiltrate of chronic inflammatory cells predominantly containing plasma cells. Immunohistochemistry for kappa and lambda light chains showed a polyclonal staining pattern confirming a diagnosis of plasma cell granuloma.

  17. Relativistic spherical plasma waves

    Science.gov (United States)

    Bulanov, S. S.; Maksimchuk, A.; Schroeder, C. B.; Zhidkov, A. G.; Esarey, E.; Leemans, W. P.

    2012-02-01

    Tightly focused laser pulses that diverge or converge in underdense plasma can generate wake waves, having local structures that are spherical waves. Here we study theoretically and numerically relativistic spherical wake waves and their properties, including wave breaking.

  18. Understanding Micro Plasmas

    CERN Document Server

    Winter, J; Böke, M; Ellerweg, D; Hemke, T; Knake, N; Mussenbrock, T; Niermann, B; Schröder, D; der Gathen, V Schulz-von; von Keudell, A

    2011-01-01

    Micro plasmas are operated around atmospheric pressure exhibiting pronounced non-equilibrium characteristics, i.e. they possess energetic electrons while ions and neutrals remain cold. They have gained significant interest due to their enormous application potential e.g. in the biomedical, surface modification and light source areas, just to name a few. Many different configurations are in use. Their understanding and quantification is mandatory for further progress in applications. We report on recent progress in the diagnostics and simulation of the entire micro plasma system from gas introduction, via the plasma discharge up to the samples at the example of a plasma jet operated in He/O2 in an ambient air environment.

  19. Plasma Cell Cheilitis

    Directory of Open Access Journals (Sweden)

    Thami Gurvinder P

    1999-01-01

    Full Text Available A case of plasma cell cheilitis with good response to glucocorticoids, is described for its rarity and probable aetiological correlation with habit of use of nasal snuff is discussed.

  20. The plasma scalpel.

    Science.gov (United States)

    Link, W J; Incropera, F P; Glover, J L

    1976-01-01

    The plasma scalpel simultaneously cuts tissue and cauterizes blood vessels measuring 3 mm in diameter with a small, hot (3000 C) gas jet. In animal studies, the amount of hemorrhage has been shown to be less with the plasma scalpel than with steel or electrosurgical scalpels, and incisions have healed without complications. Amount of damaged tissue is limited. Human trials are under way, and the device shows promise as a clinical tool.

  1. Plasma Spray Forming

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In the course of plasma spray, the plasma jet is comprehensively functioned by such effects as thermal pinch, magnetic pinch and mechanical compression and the flow is jetting at a high speed, the energy is concentrated and its center temperature is so high as to reach upwards of 15 000 ℃ which is capable of melting various kinds of materials inclusive of ceramic, it has a broad applied prospects in the fields of automobile, electronics, telecommunications, medical treatment, air navigation & space navigati...

  2. Plasma-aided manufacturing

    Science.gov (United States)

    Shohet, J. L.

    1993-12-01

    Plasma-aided manufacturing is used for producing new materials with unusual and superior properties, for developing new chemical compounds and processes, for machining, and for altering and refining materials and surfaces. Plasma-aided manufacturing has direct applications to semiconductor fabrication, materials synthesis, welding, lighting, polymers, anti-corrosion coatings, machine tools, metallurgy, electrical and electronics devices, hazardous waste removal, high performance ceramics, and many other items in both the high-technology and the more traditional industries in the United States.

  3. Particle acceleration by plasma

    CERN Document Server

    Ogata, A

    2002-01-01

    Plasma acceleration is carried out by using potential of plasma wave. It is classified by generation method of plasma wave such as the laser wake-field acceleration and the beat wave acceleration. Other method using electron beam is named the plasma wake-field acceleration (or beam wake-field acceleration). In this paper, electron acceleration by laser wake-field in gas plasma, ion source by laser radiation of solid target and nanoion beam generation by one component of plasma in trap are explained. It is an applicable method that ions, which run out from the solid target irradiated by laser, are used as ion source of accelerator. The experimental system using 800 nm laser, 50 mJ pulse energy and 50 fs pulse width was studied. The laser intensity is 4x10 sup 1 sup 6 Wcm sup - sup 2 at the focus. The target film of metal and organic substance film was used. When laser irradiated Al target, two particles generated, in front and backward. It is new fact that the neutral particle was obtained in front, because it...

  4. Plasma Injection Schemes for Laser-Plasma Accelerators

    OpenAIRE

    J. Faure

    2017-01-01

    Plasma injection schemes are crucial for producing high-quality electron beams in laser-plasma accelerators. This article introduces the general concepts of plasma injection. First, a Hamiltonian model for particle trapping and acceleration in plasma waves is introduced; ionization injection and colliding-pulse injection are described in the framework of this Hamiltonian model. We then proceed to consider injection in plasma density gradients.

  5. Plasma surface modification of polymers

    Science.gov (United States)

    Hirotsu, T.

    1980-01-01

    Thin plasma polymerization films are discussed from the viewpoint of simplicity in production stages. The application of selective, absorbent films and films used in selective permeability was tested. The types of surface modification of polymers discussed are: (1) plasma etching, (2) surface coating by plasma polymerized thin films, and (3) plasma activation surface graft polymerization.

  6. Plasma-based accelerator structures

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Carl B. [Univ. of California, Berkeley, CA (United States)

    1999-12-01

    Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas.

  7. Identification of fibrin clot-bound plasma proteins.

    Directory of Open Access Journals (Sweden)

    Simone Talens

    Full Text Available Several proteins are known to bind to a fibrin network and to change clot properties or function. In this study we aimed to get an overview of fibrin clot-bound plasma proteins. A plasma clot was formed by adding thrombin, CaCl(2 and aprotinin to citrated platelet-poor plasma and unbound proteins were washed away with Tris-buffered saline. Non-covalently bound proteins were extracted, separated with 2D gel electrophoresis and visualized with Sypro Ruby. Excised protein spots were analyzed with mass spectrometry. The identity of the proteins was verified by checking the mass of the protein, and, if necessary, by Western blot analysis. Next to established fibrin-binding proteins we identified several novel fibrin clot-bound plasma proteins, including α(2-macroglobulin, carboxypeptidase N, α(1-antitrypsin, haptoglobin, serum amyloid P, and the apolipoproteins A-I, E, J, and A-IV. The latter six proteins are associated with high-density lipoprotein particles. In addition we showed that high-density lipoprotein associated proteins were also present in fibrinogen preparations purified from plasma. Most plasma proteins in a fibrin clot can be classified into three groups according to either blood coagulation, protease inhibition or high-density lipoprotein metabolism. The presence of high-density lipoprotein in clots might point to a role in hemostasis.

  8. A re-assessment of biochemical marker distributions in T21 affected and unaffected twin pregnancies in the first trimester

    DEFF Research Database (Denmark)

    Madsen, Helen Nordahl; Ball, Susan; Wright, Dave

    2011-01-01

    increased the detection rate for fetal trisomy 21 in dizygotic twin pregnancies from 78 to 90%, and decreased the false-positive rate from 8.0 to 5.9%. CONCLUSION: Generation of chorionicity-specific medians for the biochemical markers and their use in risk assessment can improve the performance of first...... of the biochemical markers were calculated. Detection rates and false-positive rates were estimated for screening tests incorporating nuchal translucency and maternal age, with and without biochemistry. RESULTS: Medians for the two biochemical markers for monochorionic and dichorionic twins in unaffected pregnancies......OBJECTIVE: To estimate the difference between levels of the two biochemical markers pregnancy-associated plasma protein-A (PAPP-A) and maternal serum free β-human chorionic gonadotropin (free β-hCG) in twin pregnancies relative to singleton pregnancies and establish an improved screening procedure...

  9. Plasma accelerator experiments in Yugoslavia

    Science.gov (United States)

    Purić, J.; Astashynski, V. M.; Kuraica, M. M.; Dojčinovié, I. P.

    2002-12-01

    An overview is given of the results obtained in the Plasma Accelerator Experiments in Belgrade, using quasi-stationary high current plasma accelerators constructed within the framework of the Yugoslavia-Belarus Joint Project. So far, the following plasma accelerators have been realized: Magnetoplasma Compressor type (MPC); MPC Yu type; one stage Erosive Plasma Dynamic System (EPDS) and, in final stage of construction two stage Quasi-Stationary High Current Plasma Accelerator (QHPA).

  10. Plasma transport in the Scrape-off-Layer of magnetically confined plasma and the plasma exhaust

    DEFF Research Database (Denmark)

    Rasmussen, Jens Juul; Naulin, Volker; Nielsen, Anders Henry

    An overview of the plasma dynamics in the Scrape-off-Layer (SOL) of magnetically confined plasma is presented. The SOL is the exhaust channel of the warm plasma from the core, and the understanding of the SOL plasma dynamics is one of the key issues in contemporary fusion research. It is essential...

  11. Turbulent complex (dusty) plasma

    Science.gov (United States)

    Zhdanov, Sergey; Schwabe, Mierk

    2017-04-01

    As a paradigm of complex system dynamics, solid particles immersed into a weakly ionized plasma, so called complex (dusty) plasmas, were (and continue to be) a subject of many detailed studies. Special types of dynamical activity have been registered, in particular, spontaneous pairing, entanglement and cooperative action of a great number of particles resulting in formation of vortices, self-propelling, tunneling, and turbulent movements. In the size domain of 1-10 mkm normally used in experiments with complex plasmas, the characteristic dynamic time-scale is of the order of 0.01-0.1 s, and these particles can be visualized individually in real time, providing an atomistic (kinetic) level of investigations. The low-R turbulent flow induced either by the instability in a complex plasma cloud or formed behind a projectile passing through the cloud is a typical scenario. Our simulations showed formation of a fully developed system of vortices and demonstrated that the velocity structure functions scale very close to the theoretical predictions. As an important element of self-organization, cooperative and turbulent particle motions are present in many physical, astrophysical, and biological systems. Therefore, experiments with turbulent wakes and turbulent complex plasma oscillations are a promising mean to observe and study in detail the anomalous transport on the level of individual particles.

  12. Plasma treatment of onychomycosis

    Science.gov (United States)

    Xiong, Zilan; Roe, Jeff; Grammer, Tim; Him, Yeon-Ho; Graves, David B.

    2015-09-01

    Onychomycosis or fungal infection of the toenail or fingernail is a common affliction. Approximately 10% of the world's adult population is estimated to suffer from onychomycosis. Current treatment options such as topical creams, oral drugs, or laser treatments are generally limited by a variety of problems. We present results for an alternative onychomycosis treatment scheme using atmospheric pressure cold air plasmas. Using thinned cow hoof as a model nail material, we tested the ability of various plasma sources to act through the model nail to eradicate either bacteria or fungus deposited on the opposite side. Following 20 minute exposure to a surface microdischarge (SMD) device operating in room air, we observed a ~ 2 log reduction of E. coli. A similar result was obtained against T. rubrum after 45 min plasma treatment. NOx species concentration penetrating through the model nail as well as uptake into the nail were measured as a function of nail thickness. We propose that these plasma-generated species, or perhaps their reaction products, are responsible for at least part of the observed anti-microbial effect. We also explore the use of ultraviolet light acting in synergy with plasma-generated chemical species.

  13. Plasma coal reprocessing

    Science.gov (United States)

    Messerle, V. E.; Ustimenko, A. B.

    2013-12-01

    Results of many years of investigations of plasma-chemical technologies for pyrolysis, hydrogenation, thermochemical preparation for combustion, gasification, and complex reprocessing of solid fuels and hydrocarbon gas cracking are represented. Application of these technologies for obtaining the desired products (hydrogen, industrial carbon, synthesis gas, valuable components of the mineral mass of coal) corresponds to modern ecological and economical requirements to the power engineering, metallurgy, and chemical industry. Plasma fuel utilization technologies are characterized by the short-term residence of reagents within a reactor and the high degree of the conversion of source substances into the desired products without catalyst application. The thermochemical preparation of the fuel to combustion is realized in a plasma-fuel system presenting a reaction chamber with a plasmatron; and the remaining plasma fuel utilization technologies, in a combined plasma-chemical reactor with a nominal power of 100 kW, whose zone of the heat release from an electric arc is joined with the chemical reaction zone.

  14. Alcohol and plasma triglycerides.

    Science.gov (United States)

    Klop, Boudewijn; do Rego, Ana Torres; Cabezas, Manuel Castro

    2013-08-01

    This study reviews recent developments concerning the effects of alcohol on plasma triglycerides. The focus will be on population, intervention and metabolic studies with respect to alcohol and plasma triglycerides. Alcohol consumption and fat ingestion are closely associated and stimulated by each other via hypothalamic signals and by an elevated cephalic response. A J-shaped relationship between alcohol intake and plasma triglycerides has been described. A normal body weight, polyphenols in red wine and specific polymorphisms of the apolipoprotein A-V and apolipoprotein C-III genes may protect against alcohol-associated hypertriglyceridemia. In contrast, obesity exaggerates alcohol-associated hypertriglyceridemia and therefore the risk of pancreatitis. High alcohol intake remains harmful since it is associated with elevated plasma triglycerides, but also with cardiovascular disease, alcoholic fatty liver disease and the development of pancreatitis. Alcohol-induced hypertriglyceridemia is due to increased very-low-density lipoprotein secretion, impaired lipolysis and increased free fatty acid fluxes from adipose tissue to the liver. However, light to moderate alcohol consumption may be associated with decreased plasma triglycerides, probably determined by the type of alcoholic beverage consumed, genetic polymorphisms and lifestyle factors. Nevertheless, patients should be advised to reduce or stop alcohol consumption in case of hypertriglyceridemia.

  15. Plasma diagnostics in plasma processing for nanotechnology and nanolevel chemistry

    Directory of Open Access Journals (Sweden)

    Hiroshi Akatsuka

    2004-01-01

    Full Text Available The author reviews the role of various plasma diagnostics in plasma processing for nanotechnology, and points out some essential methods of spectroscopic methods to diagnose plasmas for nanoprocessing. Two experimental examples are discussed between the characteristics of nanomaterials and plasma parameters. One is measurement of rotation temperature in processing of carbon nanotube. The other is that of vibrational temperature in surface nitriding of titanium by nitrogen plasma processing. We summarize what to measure and how to measure them from the technical viewpoint of plasma diagnostics.

  16. Optical plasma torch electron bunch generation in plasma wakefield accelerators

    Directory of Open Access Journals (Sweden)

    G. Wittig

    2015-08-01

    Full Text Available A novel, flexible method of witness electron bunch generation in plasma wakefield accelerators is described. A quasistationary plasma region is ignited by a focused laser pulse prior to the arrival of the plasma wave. This localized, shapeable optical plasma torch causes a strong distortion of the plasma blowout during passage of the electron driver bunch, leading to collective alteration of plasma electron trajectories and to controlled injection. This optically steered injection is more flexible and faster when compared to hydrodynamically controlled gas density transition injection methods.

  17. Plasma rico en plaquetas Platelet -rich plasma

    Directory of Open Access Journals (Sweden)

    J. González Lagunas

    2006-04-01

    Full Text Available El Plasma Rico en Plaquetas es una suspensión concentrada de la sangre centrifugada que contiene elevadas concentraciones de trombocitos. Durante los últimos años, este producto ha aparecido de forma repetida en publicaciones científicas y en medios de comunicación generales como un producto que por sus características induce la curación y regeneración de los tejidos. La premisa de su uso es que las elevadas concentraciones de plaquetas en el PRP, liberan cantidades significativas de factores de crecimiento. En este artículo se van a recoger las evidencias científicas que se han presentado en la literatura médica con respecto al PRP y a la curación ósea, así como las diferentes aplicaciones clínicas que se han sugerido.Platelet-rich plasma is a by-product of centrifuged whole blood that contains high levels of thrombocytes. In the last decade, scientific and media interest has been generated by this product that apparently has the capacity of inducing and promoting tissue healing and regeneration. The premise of its use is that the large number of platelets in PRP release significant amounts of growth factors. In this paper, a critical review of the medical literature regarding PRP and bone healing will be presented. Also, the suggested clinical applications of the product will be addressed.

  18. Rabbit serum amyloid protein A: expression and primary structure deduced from cDNA sequences.

    Science.gov (United States)

    Rygg, M; Marhaug, G; Husby, G; Dowton, S B

    1991-12-01

    Serum amyloid A protein (SAA), the precursor of amyloid protein A (AA) in deposits of secondary amyloidosis, is an acute phase plasma apolipoprotein produced by hepatocytes. The primary structure of SAA demonstrates high interspecies homology. Several isoforms exist in individual species, probably with different amyloidogenic potential. The nucleotide sequences of two different rabbit serum amyloid A cDNA clones have been analysed, one (corresponding to SAA1) 569 base pairs (bp) long and the other (corresponding to SAA2) 513 bp long. Their deduced amino acid sequences differ at five amino acid positions, four of which are located in the NH2-terminal region of the protein. The deduced amino acid sequence of SAA2 corresponds to rabbit protein AA previously described except for one amino acid in position 22. Eighteen hours after turpentine stimulation, rabbit SAA mRNA is abundant in liver, while lower levels are present in spleen. None of the other extrahepatic organs studied showed any SAA mRNA expression. A third mRNA species (1.9 kb) hybridizing with a single-stranded RNA probe transcribed from the rabbit SAA cDNA, was identified. SAA1 and SAA2 mRNA were found in approximately equal amounts in turpentine-stimulated rabbit liver, but seem to be coordinately decreased after repeated inflammatory stimulation.

  19. Plasma Colloquium Travel Grant Program

    Energy Technology Data Exchange (ETDEWEB)

    Hazeltine, R.D.

    1998-09-14

    OAK B188 Plasma Colloquium Travel Grant Program. The purpose of the Travel Grant Program is to increase the awareness of plasma research. The new results and techniques of plasma research in fusion plasmas, plasma processing space plasmas, basic plasma science, etc, have broad applicability throughout science. The benefits of these results are limited by the relatively low awareness and appreciation of plasma research in the larger scientific community. Whereas spontaneous interactions between plasma scientists and other scientists are useful, a focused effort in education and outreach to other scientists is efficient and is needed. The academic scientific community is the initial focus of this effort, since that permits access to a broad cross-section of scientists and future scientists including undergraduates, graduate students, faculty, and research staff.

  20. Quantum Plasmas An Hydrodynamic Approach

    CERN Document Server

    Haas, Fernando

    2011-01-01

    This book provides an overview of the basic concepts and new methods in the emerging scientific area known as quantum plasmas. In the near future, quantum effects in plasmas will be unavoidable, particularly in high density scenarios such as those in the next-generation intense laser-solid density plasma experiment or in compact astrophysics objects. Currently, plasmas are in the forefront of many intriguing questions around the transition from microscopic to macroscopic modeling of charged particle systems. Quantum Plasmas: an Hydrodynamic Approach is devoted to the quantum hydrodynamic model paradigm, which, unlike straight quantum kinetic theory, is much more amenable to investigate the nonlinear realm of quantum plasmas. The reader will have a step-by-step construction of the quantum hydrodynamic method applied to plasmas. The book is intended for specialists in classical plasma physics interested in methods of quantum plasma theory, as well as scientists interested in common aspects of two major areas of...

  1. Plasma cell leukemia

    DEFF Research Database (Denmark)

    Fernández de Larrea, C; Kyle, R A; Durie, B G M

    2013-01-01

    Plasma cell leukemia (PCL) is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells. It is classified as either primary PCL occurring at diagnosis or as secondary PCL in patients with relapsed/refractory myeloma. Primary PCL is a distinct clinic......-pathological entity with different cytogenetic and molecular findings. The clinical course is aggressive with short remissions and survival duration. The diagnosis is based upon the percentage (≥ 20%) and absolute number (≥ 2 × 10(9)/l) of plasma cells in the peripheral blood. It is proposed that the thresholds...... regimens and bortezomib-based regimens are recommended followed by high-dose therapy with autologous stem cell transplantation if feasible. Allogeneic transplantation can be considered in younger patients. Prospective multicenter studies are required to provide revised definitions and better understanding...

  2. Photon kinetics in plasmas

    Directory of Open Access Journals (Sweden)

    V.G. Morozov

    2009-01-01

    Full Text Available We present a kinetic theory of radiative processes in many-component plasmas with relativistic electrons and nonrelativistic heavy particles. Using the non-equilibrium Green's function technique in many-particle QED, we show that the transverse field correlation functions can be naturally decomposed into sharply peaked (non-Lorentzian parts that describe resonant (propagating photons and off-shell parts corresponding to virtual photons in the medium. Analogous decompositions are obtained for the longitudinal field correlation functions and the correlation functions of relativistic electrons. We derive a kinetic equation for the resonant photons with a finite spectral width and show that the off-shell parts of the particle and field correlation functions are essential to calculate the local radiating power in plasmas and recover the results of vacuum QED. The plasma effects on radiative processes are discussed.

  3. Large area plasma source

    Science.gov (United States)

    Foster, John (Inventor); Patterson, Michael (Inventor)

    2008-01-01

    An all permanent magnet Electron Cyclotron Resonance, large diameter (e.g., 40 cm) plasma source suitable for ion/plasma processing or electric propulsion, is capable of producing uniform ion current densities at its exit plane at very low power (e.g., below 200 W), and is electrodeless to avoid sputtering or contamination issues. Microwave input power is efficiently coupled with an ionizing gas without using a dielectric microwave window and without developing a throat plasma by providing a ferromagnetic cylindrical chamber wall with a conical end narrowing to an axial entrance hole for microwaves supplied on-axis from an open-ended waveguide. Permanent magnet rings are attached inside the wall with alternating polarities against the wall. An entrance magnet ring surrounding the entrance hole has a ferromagnetic pole piece that extends into the chamber from the entrance hole to a continuing second face that extends radially across an inner pole of the entrance magnet ring.

  4. Plasma Simulation Program

    Energy Technology Data Exchange (ETDEWEB)

    Greenwald, Martin

    2011-10-04

    Many others in the fusion energy and advanced scientific computing communities participated in the development of this plan. The core planning team is grateful for their important contributions. This summary is meant as a quick overview the Fusion Simulation Program's (FSP's) purpose and intentions. There are several additional documents referenced within this one and all are supplemental or flow down from this Program Plan. The overall science goal of the DOE Office of Fusion Energy Sciences (FES) Fusion Simulation Program (FSP) is to develop predictive simulation capability for magnetically confined fusion plasmas at an unprecedented level of integration and fidelity. This will directly support and enable effective U.S. participation in International Thermonuclear Experimental Reactor (ITER) research and the overall mission of delivering practical fusion energy. The FSP will address a rich set of scientific issues together with experimental programs, producing validated integrated physics results. This is very well aligned with the mission of the ITER Organization to coordinate with its members the integrated modeling and control of fusion plasmas, including benchmarking and validation activities. [1]. Initial FSP research will focus on two critical Integrated Science Application (ISA) areas: ISA1, the plasma edge; and ISA2, whole device modeling (WDM) including disruption avoidance. The first of these problems involves the narrow plasma boundary layer and its complex interactions with the plasma core and the surrounding material wall. The second requires development of a computationally tractable, but comprehensive model that describes all equilibrium and dynamic processes at a sufficient level of detail to provide useful prediction of the temporal evolution of fusion plasma experiments. The initial driver for the whole device model will be prediction and avoidance of discharge-terminating disruptions, especially at high performance, which are a

  5. The 2012 Plasma Roadmap

    Science.gov (United States)

    Samukawa, Seiji; Hori, Masaru; Rauf, Shahid; Tachibana, Kunihide; Bruggeman, Peter; Kroesen, Gerrit; Whitehead, J. Christopher; Murphy, Anthony B.; Gutsol, Alexander F.; Starikovskaia, Svetlana; Kortshagen, Uwe; Boeuf, Jean-Pierre; Sommerer, Timothy J.; Kushner, Mark J.; Czarnetzki, Uwe; Mason, Nigel

    2012-06-01

    Low-temperature plasma physics and technology are diverse and interdisciplinary fields. The plasma parameters can span many orders of magnitude and applications are found in quite different areas of daily life and industrial production. As a consequence, the trends in research, science and technology are difficult to follow and it is not easy to identify the major challenges of the field and their many sub-fields. Even for experts the road to the future is sometimes lost in the mist. Journal of Physics D: Applied Physics is addressing this need for clarity and thus providing guidance to the field by this special Review article, The 2012 Plasma Roadmap. Although roadmaps are common in the microelectronic industry and other fields of research and development, constructing a roadmap for the field of low-temperature plasmas is perhaps a unique undertaking. Realizing the difficulty of this task for any individual, the plasma section of the Journal of Physics D Board decided to meet the challenge of developing a roadmap through an unusual and novel concept. The roadmap was divided into 16 formalized short subsections each addressing a particular key topic. For each topic a renowned expert in the sub-field was invited to express his/her individual visions on the status, current and future challenges, and to identify advances in science and technology required to meet these challenges. Together these contributions form a detailed snapshot of the current state of the art which clearly shows the lifelines of the field and the challenges ahead. Novel technologies, fresh ideas and concepts, and new applications discussed by our authors demonstrate that the road to the future is wide and far reaching. We hope that this special plasma science and technology roadmap will provide guidance for colleagues, funding agencies and government institutions. If successful in doing so, the roadmap will be periodically updated to continue to help in guiding the field.

  6. Solar flares. [plasma physics

    Science.gov (United States)

    Rust, D. M.

    1979-01-01

    The present paper deals with explosions in a magnetized solar plasma, known as flares, whose effects are seen throughout the electromagnetic spectrum, from gamma-rays through the visible and to the radio band. The diverse phenomena associated with flares are discussed, along with the physical mechanisms that have been advanced to explain them. The impact of solar flare research on the development of plasma physics and magnetohydrodynamics is noted. The rapid development of solar flare research during the past 20 years, owing to the availability of high-resolution images, detailed magnetic field measurements, and improved spectral data, is illustrated.

  7. Kinetics of complex plasmas

    CERN Document Server

    Sodha, Mahendra Singh

    2014-01-01

    The presentation in the book is based on charge balance on the dust particles, number and energy balance of the constituents and atom-ion-electron interaction in the gaseous plasma. Size distribution of dust particles, statistical mechanics, Quantum effects in electron emission from and accretion on dust particles and nonlinear interaction of complex plasmas with electric and electromagnetic fields have been discussed in the book. The book introduces the reader to basic concepts and typical applications. The book should be of use to researchers, engineers and graduate students.

  8. Plasma Cell Disorders.

    Science.gov (United States)

    Castillo, Jorge J

    2016-12-01

    Plasma cell disorders are benign, premalignant, and malignant conditions characterized by the presence of a monoclonal paraprotein detected in serum or urine. These conditions are biologically, pathologically, and clinically heterogeneous. There have been major advances in the understanding of the biology of these diseases, which are promoting the development of therapies with novel mechanisms of action. Novel agents such as proteasome inhibitors, immunomodulatory drugs, and monoclonal antibodies have gained approval in the United States and Europe for the treatment of plasma cell disorders. Such therapies are translating into higher rates of response and survival and better toxicity profiles. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Plasma YKL-40

    DEFF Research Database (Denmark)

    Jensen, Peter; Wiell, C; Milting, K

    2013-01-01

    Background  Plasma YKL-40 is an inflammatory biomarker. No useful biomarker exists in patients with psoriasis or psoriatic arthritis. Objective  To measure YKL-40 and high-sensitivity C-reactive protein (hs-CRP) in patients with psoriasis or psoriatic arthritis before and during treatment. Methods......-CRP at inclusion and during 48 weeks of adalimumab treatment. The patients with psoriatic arthritis were divided into responders and non-responders. Results  In patients with psoriasis, the baseline median PASI score was 10.8 and baseline YKL-40 was 45 μg/L. Seventeen per cent had elevated plasma YKL-40 compared...

  10. Plasma polarization spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, Takashi; Iwamae, Atsushi (eds.) [Kyoto Univ. (Japan). Dept. of Mechanical Engineering and Science

    2008-07-01

    Plasma Polarization Spectroscopy (PPS) is now becoming a standard diagnostic technique for working with laboratory plasmas. This new area needs a comprehensive framework, both experimental and theoretical. This book reviews the historical development of PPS, develops a general theoretical formulation to deal with this phenomenon, along with an overview of relevant cross sections, and reports on laboratory experiments so far performed. It also includes various facets that are interesting from this standpoint, e.g. X-ray lasers and effects of microwave irradiation. It also offers a timely discussion of instrumentation that is quite important in a practical PPS experiment. (orig.)

  11. Plasma Assisted Combustion

    Science.gov (United States)

    2007-02-28

    pressure hydrogen is given in Fig. 2.14. The regions typical for “common” glow discharges (negative glow, Faraday dark space, and positive column) are...Hollenstein Ch. Plasma Phys. Control. Fusion, 42 (2000) 93. [107] M.A. Heald and C.B. Wahrton, Plasma diagnostics with microwaves, John Wi- ley &Sons, New York...Nitrous Oxide J. Chem. Soc. Faraday Trans. 69 352 [194] Albers E A, Hoyermann K, Schacke H, Schmatjko K J, Wagner H Gg, Wolfrum J 1975 Absolute Rate

  12. Cell wall proteins: a new insight through proteomics.

    Science.gov (United States)

    Jamet, Elisabeth; Canut, Hervé; Boudart, Georges; Pont-Lezica, Rafael F

    2006-01-01

    Cell wall proteins are essential constituents of plant cell walls; they are involved in modifications of cell wall components, wall structure, signaling and interactions with plasma membrane proteins at the cell surface. The application of proteomic approaches to the cell wall compartment raises important questions: are there technical problems specific to cell wall proteomics? What kinds of proteins can be found in Arabidopsis walls? Are some of them unexpected? What sort of post-translational modifications have been characterized in cell wall proteins to date? The purpose of this review is to discuss the experimental results obtained to date using proteomics, as well as some of the new questions challenging future research.

  13. Optical properties of cluster plasma

    Energy Technology Data Exchange (ETDEWEB)

    Kishimoto, Yasuaki; Tajima, Toshiki [Japan Atomic Energy Research Inst., Neyagawa, Osaka (Japan). Kansai Research Establishment; Downer, M.C.

    1998-03-01

    It is shown that unlike a gas plasma or an electron plasma in a metal, an ionized clustered material (`cluster plasma`) permits propagation below the plasma cut-off of electromagnetic (EM) waves whose phase velocity is close to but below the speed of light. This results from the excitation of a plasma oscillation mode (and/or polarization mode) through the cluster surface which does not exist in usual gaseous plasma. The existence of this new optical mode, cluster mode, is confirmed via numerical simulation. (author)

  14. Plasma scattering of electromagnetic radiation

    CERN Document Server

    Sheffield, John

    1975-01-01

    Plasma Scattering of Electromagnetic Radiation covers the theory and experimental application of plasma scattering. The book discusses the basic properties of a plasma and of the interaction of radiation with a plasma; the relationship between the scattered power spectrum and the fluctuations in plasma density; and the incoherent scattering of low-temperature plasma. The text also describes the constraints and problems that arise in the application of scattering as a diagnostic technique; the characteristic performance of various dispersion elements, image dissectors, and detectors; and the ge

  15. Some plasma aspects and plasma diagnostics of ion sources.

    Science.gov (United States)

    Wiesemann, Klaus

    2008-02-01

    We consider plasma properties in the most advanced type of plasma ion sources, electron cyclotron resonance ion sources for highly charged ions. Depending on the operation conditions the plasma in these sources may be highly ionized, which completely changes its transport properties. The most striking difference to weakly ionized plasma is that diffusion will become intrinsically ambipolar. We further discuss means of plasma diagnostics. As noninvasive diagnostic methods we will discuss analysis of the ion beam, optical spectroscopy, and measurement of the x-ray bremsstrahlung continuum. From beam analysis and optical spectroscopy one may deduce ion densities, and electron densities and distribution functions as a mean over the line of sight along the axis (optical spectroscopy) or at the plasma edge (ion beam). From x-ray spectra one obtains information about the population of highly energetic electrons and the energy transfer from the driving electromagnetic waves to the plasma -- basic data for plasma modeling.

  16. The field of plasmas. L'univers des plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Bradu, P. (Direction des Recherches, Etudes et Techniques d' Armement (DRET), (France))

    1999-01-01

    Plasma is the fourth state of matter and it is the most spread at the scale of universe. Plasma is involved in natural phenomena such as Saint-Elmo's fires, aurora borealis or lightning discharges. Thanks to its particular properties plasma is used in many fields of technology. We find plasmas in light bulbs, television screens and in diverse industrial processes such as laser isotope separation, sterilization, surface coating, or waste treatment where a plasma torch is used to reduce waste into its elementary components trapped in the molten bulk. Spatial propulsion could soon benefit by the application of magnetohydrodynamics effects to plasmas. Thermonuclear reactors where fusion reactions take place in a very hot plasma could be the source of energy for the next century. This book deals with all the aspects of plasma in the technology of today. (A.C.) 21 refs.

  17. The field of plasmas; L`univers des plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Bradu, P. [Direction des Recherches, Etudes et Techniques d`Armement (DRET), (France)

    1999-12-01

    Plasma is the fourth state of matter and it is the most spread at the scale of universe. Plasma is involved in natural phenomena such as Saint-Elmo`s fires, aurora borealis or lightning discharges. Thanks to its particular properties plasma is used in many fields of technology. We find plasmas in light bulbs, television screens and in diverse industrial processes such as laser isotope separation, sterilization, surface coating, or waste treatment where a plasma torch is used to reduce waste into its elementary components trapped in the molten bulk. Spatial propulsion could soon benefit by the application of magnetohydrodynamics effects to plasmas. Thermonuclear reactors where fusion reactions take place in a very hot plasma could be the source of energy for the next century. This book deals with all the aspects of plasma in the technology of today. (A.C.) 21 refs.

  18. Microwave Probing of Air-Plasma and Plasma Metamaterials

    Science.gov (United States)

    Schneider, Katherine; Rock, Ben; Helle, Mike

    2016-10-01

    Plasma metamaterials are of recent interest due to their unique ability to be engineered with specific electromagnetic responses. One potential metamaterial architecture is based on a `forest' of plasma rods that can be produced using intense laser plasma filaments. In our work, we use a continuous microwave source at 26.5 GHz to measure a single air plasma filament characteristics generated from a 5 mJ laser pulse within a cylindrical hole in a Ka-band waveguide. Preliminary results show the air plasma produces a strong shock and acts to reflect microwave radiation. A computational comparison using 3D EM modeling is performed to examine the reflection and transmission properties of a single plasma rod, and further, to investigate an array of plasma rods as a potential plasma based metamaterial.

  19. Partially ionized plasmas including the third symposium on uranium plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, M. [ed.

    1976-09-01

    Separate abstracts are included for 28 papers on electrically generated plasmas, fission generated plasmas, nuclear pumped lasers, gaseous fuel reactor research, and applications. Five papers have been previously abstracted and included in ERA.

  20. Plasma detachment with molecular processes in divertor plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, N.; Ezumi, N.; Nishijima, D.; Takamura, S. [Dept. of Energy Engineering and Science, Graduate School of Engineering, Nagoya Univ., Nagoya, Aichi (Japan); Krasheninnikov, S.I.; Pigarov, A.Yu. [MIT Plasma Science and Fusion Center, Cambridge, MA (United States)

    2000-01-01

    Molecular processes in detached recombining plasmas are briefly reviewed. Several reactions with vibrationally excited hydrogen molecule related to recombination processes are described. Experimental evidence of molecular activated recombination observed in a linear divertor plasma simulator is also shown. (author)

  1. Plasma flow in peripheral region of detached plasma in linear plasma device

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Y., E-mail: hayashi-yuki13@ees.nagoya-u.ac.jp; Ohno, N. [Graduate School of Engineering, Nagoya University, Nagoya, Aichi 464-8603 (Japan); Kajita, S. [EcoTopia Science Institute, Nagoya University, Nagoya, Aichi 464-8603 (Japan); Tanaka, H. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan)

    2016-01-15

    A plasma flow structure is investigated using a Mach probe under detached plasma condition in a linear plasma device NAGDIS-II. A reverse flow along the magnetic field is observed in a steady-state at far-peripheral region of the plasma column in the upstream side from the recombination front. These experimental results indicate that plasma near the recombination front should strongly diffuse across the magnetic field, and it should be transported along the magnetic field in the reverse flow direction. Furthermore, bursty plasma density fluctuations associated with intermittent convective plasma transport are observed in the far-peripheral region of the plasma column in both upstream and downstream sides from the recombination front. Such a nondiffusive transport can contribute to the intermittent reverse plasma flow, and the experimental results indicate that intermittent transports are frequently produced near the recombination front.

  2. Laser-plasma-based linear collider using hollow plasma channels

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, C.B., E-mail: CBSchroeder@lbl.gov; Benedetti, C.; Esarey, E.; Leemans, W.P.

    2016-09-01

    A linear electron–positron collider based on laser-plasma accelerators using hollow plasma channels is considered. Laser propagation and energy depletion in the hollow channel is discussed, as well as the overall efficiency of the laser-plasma accelerator. Example parameters are presented for a 1-TeV and 3-TeV center-of-mass collider based on laser-plasma accelerators.

  3. Serum concentrations of the biomarkers CA125, CA15-3, CA72-4, tPSA and PAPP-A in natural and stimulated ovarian cycles

    Directory of Open Access Journals (Sweden)

    Melissa Stemp

    2014-06-01

    Conclusion: Ovarian stimulation reduced serum PAPP‐A levels, CA125 and CA15‐3 levels were generally unaffected by ovarian stimulation but displayed cyclical changes throughout both natural and stimulated cycles, whilst tPSA and CA72-4 were not affected by the stage of the cycle or ovarian stimulation.

  4. Computations in Plasma Physics.

    Science.gov (United States)

    Cohen, Bruce I.; Killeen, John

    1983-01-01

    Discusses contributions of computers to research in magnetic and inertial-confinement fusion, charged-particle-beam propogation, and space sciences. Considers use in design/control of laboratory and spacecraft experiments and in data acquisition; and reviews major plasma computational methods and some of the important physics problems they…

  5. Merging of plasma currents

    NARCIS (Netherlands)

    Bergmans, J.; Schep, T. J.

    2001-01-01

    The merging process of current filaments in a strongly magnetized plasma is described. The evolution is calculated using a contour dynamics method, which accurately tracks piecewise constant distributions of the conserved quantities. In the interaction of two screened currents, both develop dipolar

  6. Microscopic plasma Hamiltonian

    Science.gov (United States)

    Peng, Y.-K. M.

    1974-01-01

    A Hamiltonian for the microscopic plasma model is derived from the Low Lagrangian after the dual roles of the generalized variables are taken into account. The resulting Hamilton equations are shown to agree with the Euler-Lagrange equations of the Low Lagrangian.

  7. Flare Plasma Iron Abundance

    Science.gov (United States)

    Dennis, Brian R.; Dan, Chau; Jain, Rajmal; Schwartz, Richard A.; Tolbert, Anne K.

    2008-01-01

    The equivalent width of the iron-line complex at 6.7 keV seen in flare X-ray spectra suggests that the iron abundance of the hottest plasma at temperatures >approx.10 MK may sometimes be significantly lower than the nominal coronal abundance of four times the photospheric value that is commonly assumed. This conclusion is based on X-ray spectral observations of several flares seen in common with the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Solar X-ray Spectrometer (SOXS) on the second Indian geostationary satellite, GSAT-2. The implications of this will be discussed as it relates to the origin of the hot flare plasma - either plasma already in the corona that is directly heated during the flare energy release process or chromospheric plasma that is heated by flare-accelerated particles and driven up into the corona. Other possible explanations of lower-than-expected equivalent widths of the iron-line complex will also be discussed.

  8. Quark gluon plasma

    Indian Academy of Sciences (India)

    C P Singh

    2000-04-01

    Recent trends in the research of quark gluon plasma (QGP) are surveyed and the current experimental and theoretical status regarding the properties and signals of QGP is reported. We hope that the experiments commencing at relativistic heavy-ion collider (RHIC) in 2000 will provide a glimpse of the QGP formation.

  9. Pulsed Plasma Electron Sources

    Science.gov (United States)

    Krasik, Yakov

    2008-11-01

    Pulsed (˜10-7 s) electron beams with high current density (>10^2 A/cm^2) are generated in diodes with electric field of E > 10^6 V/cm. The source of electrons in these diodes is explosive emission plasma, which limits pulse duration; in the case E Hadas and Ya. E. Krasik, Europhysics Lett. 82, 55001 (2008).

  10. Plasma Theory and Simulation.

    Science.gov (United States)

    1982-12-31

    expan- sion of a warm plasma; launching and propagation and decay of very large amplitude waves (8GK, solitons, etc.); thermal barriers (really...25.373.1981. ION-10N TWO-STREAM IN THERMAL BARRIERS : Vincent-lhonal,U.C.Berkeley. We present stu- dies or the eleclroTatic ion-ion two-stream instability as

  11. Plasma Theory and Simulation.

    Science.gov (United States)

    1980-09-30

    William Nevins L439 LLL (422-7032) Lecturers , UCB; Physicists -LLL Dr. William Fawley Guest, UCB; Physicist LLL L321 LLL (422-9272) Yu-Jiuan Chen, Douglas... MHD - Particle Codes." Three abstracts of papers prepared for the APS Division of Plasma Physics Meeting, November 10-14, 1980, at San Diego, follow

  12. Vacuum plasma spray coating

    Science.gov (United States)

    Holmes, Richard R.; Mckechnie, Timothy N.

    1989-01-01

    Currently, protective plasma spray coatings are applied to space shuttle main engine turbine blades of high-performance nickel alloys by an air plasma spray process. Originally, a ceramic coating of yttria-stabilized zirconia (ZrO2.12Y2O3) was applied for thermal protection, but was removed because of severe spalling. In vacuum plasma spray coating, plasma coatings of nickel-chromium-aluminum-yttrium (NiCrAlY) are applied in a reduced atmosphere of argon/helium. These enhanced coatings showed no spalling after 40 MSFC burner rig thermal shock cycles between 927 C (1700 F) and -253 C (-423 F), while current coatings spalled during 5 to 25 test cycles. Subsequently, a process was developed for applying a durable thermal barrier coating of ZrO2.8Y2O3 to the turbine blades of first-stage high-pressure fuel turbopumps utilizing the enhanced NiCrAlY bond-coating process. NiCrAlY bond coating is applied first, with ZrO2.8Y2O3 added sequentially in increasing amounts until a thermal barrier coating is obtained. The enchanced thermal barrier coating has successfully passed 40 burner rig thermal shock cycles.

  13. Fundamentals of plasma physics

    CERN Document Server

    Bittencourt, J A

    1986-01-01

    A general introduction designed to present a comprehensive, logical and unified treatment of the fundamentals of plasma physics based on statistical kinetic theory. Its clarity and completeness make it suitable for self-learning and self-paced courses. Problems are included.

  14. Molecular biological characterization of equine surfactant protein A.

    Science.gov (United States)

    Hospes, R; Hospes, B I L; Reiss, I; Bostedt, H; Gortner, L

    2002-12-01

    In the following, we describe the isolation and sequencing of the equine surfactant protein A (Sp-A) as found in both the cDNA and the genomic DNA. We found a length of the cDNA sequence of 747 bp (base pairs), in translation into amino acids of 248. Compared with the known molecular biological facts about Sp-A in other species, the cDNA sequence obtained showed highest homology with that of sheep (85.01%). The genomic DNA of equine Sp-A, as in other species, includes three introns. There were no hints for the existence of two different Sp-A genes. These results should form the basis for a better understanding of respiratory failure in foals and adult horses, and also lead to further studies on this item.

  15. Magnetized Plasma Experiments Using Thermionic- Thermoelectronic Plasma Emitter

    Science.gov (United States)

    Kawamori, Eiichirou; Cheng, C. Z.; Fujikawa, Nobuko; Lee, Jyun-Yi; Peng, Albert

    2008-11-01

    We are developing a magnetic mirror device, which is the first magnetized plasma device in Taiwan, to explore basic plasma sciences relevant to fusion, space and astrophysical plasmas. Our research subjects include electromagnetically induced transparency (EIT), Alfven wave physics, and plasma turbulence. A large diameter (> 200 mm) plasma emitter1, which utilizes thermionic- thermoelectronic emission from a mixture of LaB6 (Lanthanum-hexaboride) and beta-eucryptite (lithium type aluminosylicate) powders, is employed as a plasma source because of its production ability of fully ionized plasma and controllability of plasma emission rate. The plasma emitter has been installed recently and investigation of its characteristics will be started. The employment of beta-eucryptite in plasma emitter is the first experimental test because such investigation of beta-eucryptite has previously been used only for Li+-ion source2. Our plan for magnetized plasma experiments and results of the plasma emitter investigation will be presented. 1. K. Saeki, S. Iizuka, N. Sato, and Y. Hatta, Appl. Phys. Lett., 37, 1980, pp. 37-38. 2. M. Ueda, R. R. Silva, R. M. Oliveira, H. Iguchi, J. Fujita and K. Kadota, J. Phys. D: Appl. Phys. 30 1997, pp. 2711--2716.

  16. The 2017 Plasma Roadmap: Low temperature plasma science and technology

    Science.gov (United States)

    Journal of Physics D: Applied Physics published the first Plasma Roadmap in 2012 consisting of the individual perspectives of 16 leading experts in the various sub-fields of low temperature plasma science and technology. The 2017 Plasma Roadmap is the first update of a planned series of periodic upd...

  17. Modelling the Plasma Jet in Multi-Arc Plasma Spraying

    Science.gov (United States)

    Bobzin, K.; Öte, M.; Schein, J.; Zimmermann, S.; Möhwald, K.; Lummer, C.

    2016-08-01

    Particle in-flight characteristics in atmospheric plasma spraying process are determined by impulse and heat energy transferred between the plasma jet and injected powder particles. One of the important factors for the quality of the plasma-sprayed coatings is thus the distribution of plasma gas temperatures and velocities in plasma jet. Plasma jets generated by conventional single-arc plasma spraying systems and their interaction with powder particles were subject matter of intensive research. However, this does not apply to plasma jets generated by means of multi-arc plasma spraying systems yet. In this study, a numerical model has been developed which is designated to dealing with the flow characteristics of the plasma jet generated by means of a three-cathode spraying system. The upstream flow conditions, which were calculated using a priori conducted plasma generator simulations, have been coupled to the plasma jet simulations. The significances of the relevant numerical assumptions and aspects of the models are analyzed. The focus is placed on to the turbulence and diffusion/demixing modelling. A critical evaluation of the prediction power of the models is conducted by comparing the numerical results to the experimental results determined by means of emission spectroscopic computed tomography. It is evident that the numerical models exhibit a good accuracy for their intended use.

  18. Theory of gas discharge plasma

    CERN Document Server

    Smirnov, Boris M

    2015-01-01

    This book presents the theory of gas discharge plasmas in a didactical way. It explains the processes in gas discharge plasmas. A gas discharge plasma is an ionized gas which is supported by an external electric field. Therefore its parameters are determined by processes in it. The properties of a gas discharge plasma depend on its gas component, types of external fields, their geometry and regimes of gas discharge. Fundamentals of a gas discharge plasma include elementary, radiative and transport processes which are included in its kinetics influence. They are represented in this book together with the analysis of simple gas discharges. These general principles are applied to stationary gas discharge plasmas of helium and argon. The analysis of such plasmas under certain conditions is theoretically determined by numerical plasma parameters for given regimes and conditions.

  19. Modelling of Complex Plasmas

    Science.gov (United States)

    Akdim, Mohamed Reda

    2003-09-01

    Nowadays plasmas are used for various applications such as the fabrication of silicon solar cells, integrated circuits, coatings and dental cleaning. In the case of a processing plasma, e.g. for the fabrication of amorphous silicon solar cells, a mixture of silane and hydrogen gas is injected in a reactor. These gases are decomposed by making a plasma. A plasma with a low degree of ionization (typically 10_5) is usually made in a reactor containing two electrodes driven by a radio-frequency (RF) power source in the megahertz range. Under the right circumstances the radicals, neutrals and ions can react further to produce nanometer sized dust particles. The particles can stick to the surface and thereby contribute to a higher deposition rate. Another possibility is that the nanometer sized particles coagulate and form larger micron sized particles. These particles obtain a high negative charge, due to their large radius and are usually trapped in a radiofrequency plasma. The electric field present in the discharge sheaths causes the entrapment. Such plasmas are called dusty or complex plasmas. In this thesis numerical models are presented which describe dusty plasmas in reactive and nonreactive plasmas. We started first with the development of a simple one-dimensional silane fluid model where a dusty radio-frequency silane/hydrogen discharge is simulated. In the model, discharge quantities like the fluxes, densities and electric field are calculated self-consistently. A radius and an initial density profile for the spherical dust particles are given and the charge and the density of the dust are calculated with an iterative method. During the transport of the dust, its charge is kept constant in time. The dust influences the electric field distribution through its charge and the density of the plasma through recombination of positive ions and electrons at its surface. In the model this process gives an extra production of silane radicals, since the growth of dust is

  20. Effect of plasma processing reactor circuitry on plasma characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Rauf, S.; Kushner, M.J. [Univ. of Illinois, Urbana, IL (United States). Dept. of Electrical and Computer Engineering

    1997-12-31

    It is well known that external circuitry greatly influences the performance of plasma processing reactors. Simulation of external circuits difficult since the time in which the external circuit attains the steady-state is several orders of magnitude longer than typical plasma simulation time scales. In this paper, the authors present a technique to simulate the external circuit concurrently with the plasma, and implement it into the Hybrid Plasma Equipment Model (HPEM). The resulting model is used to investigate the influence of external circuitry on plasma behavior.

  1. Numerical simulation of dusty plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Winske, D.

    1995-09-01

    The numerical simulation of physical processes in dusty plasmas is reviewed, with emphasis on recent results and unresolved issues. Three areas of research are discussed: grain charging, weak dust-plasma interactions, and strong dust-plasma interactions. For each area, we review the basic concepts that are tested by simulations, present some appropriate examples, and examine numerical issues associated with extending present work.

  2. The Plasma Archipelago: Plasma Physics in the 1960s

    Science.gov (United States)

    Weisel, Gary J.

    2017-09-01

    With the foundation of the Division of Plasma Physics of the American Physical Society in April 1959, plasma physics was presented as the general study of ionized gases. This paper investigates the degree to which plasma physics, during its first decade, established a community of interrelated specialties, one that brought together work in gaseous electronics, astrophysics, controlled thermonuclear fusion, space science, and aerospace engineering. It finds that, in some regards, the plasma community was indeed greater than the sum of its parts and that its larger identity was sometimes glimpsed in inter-specialty work and studies of fundamental plasma behaviors. Nevertheless, the plasma specialties usually worked separately for two inter-related reasons: prejudices about what constituted "basic physics," both in the general physics community and within the plasma community itself; and a compartmentalized funding structure, in which each funding agency served different missions.

  3. Snake venom. The amino acid sequence of protein A from Dendroaspis polylepis polylepis (black mamba) venom.

    Science.gov (United States)

    Joubert, F J; Strydom, D J

    1980-12-01

    Protein A from Dendroaspis polylepis polylepis venom comprises 81 amino acids, including ten half-cystine residues. The complete primary structures of protein A and its variant A' were elucidated. The sequences of proteins A and A', which differ in a single position, show no homology with various neurotoxins and non-neurotoxic proteins and represent a new type of elapid venom protein.

  4. The Plasma Chemistry of Polymer Surfaces

    CERN Document Server

    Friedrich, Jö

    2012-01-01

    This book illustrates plasma properties, polymer characteristics, surface specifics, and how to purposefully combine plasma and polymer chemistry. In so doing, it covers plasma polymerization, surface functionalization, etching, crosslinking, and deposition of monotype functional-group-bearing plasma polymers. It explains different techniques and plasma types, such as pressure-pulsed, remote, low-wattage plasmas and plasma polymerization in liquids. Finally, among the numerous applications discussed are plasmas for chemical synthesis, industrial processes or the modification of membranes and p

  5. Modulational interactions in quantum plasmas

    CERN Document Server

    Sayed, Fatema; Tyshetskiy, Yuriy; Ishihara, Osamu

    2013-01-01

    A formalism for treating modulational interactions of electrostatic fields in collisionless quantum plasmas is developed, based on the kinetic Wigner-Poisson model of quantum plasma. This formalism can be used in a range of problems of nonlinear interaction between electrostatic fields in a quantum plasma, such as development of turbulence, self-organization, as well as transition from the weak turbulent state to strong turbulence. In particular, using this formalism, we obtain the kinetic quantum Zakharov equations, that describe nonlinear coupling of high frequency Langmuir waves to low frequency plasma density variations, for cases of non-degenerate and degenerate plasma electrons.

  6. Closed inductively coupled plasma cell

    Science.gov (United States)

    Manning, Thomas J.; Palmer, Byron A.; Hof, Douglas E.

    1990-01-01

    A closed inductively coupled plasma cell generates a relatively high power, low noise plasma for use in spectroscopic studies. A variety of gases can be selected to form the plasma to minimize spectroscopic interference and to provide a electron density and temperature range for the sample to be analyzed. Grounded conductors are placed at the tube ends and axially displaced from the inductive coil, whereby the resulting electromagnetic field acts to elongate the plasma in the tube. Sample materials can be injected in the plasma to be excited for spectroscopy.

  7. Experimental plasma research project summaries

    Energy Technology Data Exchange (ETDEWEB)

    1978-08-01

    This report contans descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Measurements and Instrumentation; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report.

  8. Experimental Plasma Research project summaries

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-09-01

    This report contains descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Diagnostics; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report.

  9. Plasma chemistry for inorganic materials

    Science.gov (United States)

    Matsumoto, O.

    1980-01-01

    Practical application of plasma chemistry to the development of inorganic materials using both low temperature and warm plasmas are summarized. Topics cover: the surface nitrification and oxidation of metals; chemical vapor deposition; formation of minute oxide particles; the composition of oxides from chloride vapor; the composition of carbides and nitrides; freezing high temperature phases by plasma arc welding and plasma jet; use of plasma in the development of a substitute for petroleum; the production of silicon for use in solar cell batteries; and insulating the inner surface of nuclear fusion reactor walls.

  10. Plasma devices for hydrocarbon reformation

    KAUST Repository

    Cha, Min Suk

    2017-02-16

    Plasma devices for hydrocarbon reformation are provided. Methods of using the devices for hydrocarbon reformation are also provided. The devices can include a liquid container to receive a hydrocarbon source, and a plasma torch configured to be submerged in the liquid. The plasma plume from the plasma torch can cause reformation of the hydrocarbon. The device can use a variety of plasma torches that can be arranged in a variety of positions in the liquid container. The devices can be used for the reformation of gaseous hydrocarbons and/or liquid hydrocarbons. The reformation can produce methane, lower hydrocarbons, higher hydrocarbons, hydrogen gas, water, carbon dioxide, carbon monoxide, or a combination thereof.

  11. Basics of plasma astrophysics

    CERN Document Server

    Chiuderi, Claudio

    2015-01-01

    This book is an introduction to contemporary plasma physics that discusses the most relevant recent advances in the field and covers a careful choice of applications to various branches of astrophysics and space science. The purpose of the book is to allow the student to master the basic concepts of plasma physics and to bring him or her up to date in a number of relevant areas of current research. Topics covered include orbit theory, kinetic theory, fluid models, magnetohydrodynamics, MHD turbulence, instabilities, discontinuities, and magnetic reconnection. Some prior knowledge of classical physics is required, in particular fluid mechanics, statistical physics, and electrodynamics. The mathematical developments are self-contained and explicitly detailed in the text. A number of exercises are provided at the end of each chapter, together with suggestions and solutions.

  12. Adiabatic plasma buncher

    Energy Technology Data Exchange (ETDEWEB)

    Ferrario, M. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati, Frascati, RM (Italy); Katsouleas, T.C. [Los Angeles Univ. of Southern California, Los Angeles, CA (United States); Serafini, L. [Istituto Nazionale di Fisica Nucleare, Milan (Italy); Ben Zvi, I. [Brookhaven National Laboratory, Upton, NY (United States)

    2000-07-01

    In this paper is presented a new scheme of injection into a plasma accelerator, aimed at producing a high quality beam while relaxing the demands on the bunch length of the injected beam. The beam dynamics in the injector, consisting of a high voltage pulsed photo-diode, is analyzed and optimized to produce a {lambda}{sub p}/20 long electron bunch at 2.5 MeV. This bunch is injected into a plasma wave in which it compresses down to {lambda}{sub p}/100 while simultaneously accelerating up to 250 MeV. This simultaneous bunching and acceleration of a high quality beam requires a proper combination of injection energy and injection phase. Preliminary results from simulations are shown to assess the potentials of the scheme.

  13. Neutrino beam plasma instability

    Indian Academy of Sciences (India)

    Vishnu M Bannur

    2001-10-01

    We derive relativistic fluid set of equations for neutrinos and electrons from relativistic Vlasov equations with Fermi weak interaction force. Using these fluid equations, we obtain a dispersion relation describing neutrino beam plasma instability, which is little different from normal dispersion relation of streaming instability. It contains new, nonelectromagnetic, neutrino-plasma (or electroweak) stable and unstable modes also. The growth of the instability is weak for the highly relativistic neutrino flux, but becomes stronger for weakly relativistic neutrino flux in the case of parameters appropriate to the early universe and supernova explosions. However, this mode is dominant only for the beam velocity greater than 0.25 and in the other limit electroweak unstable mode takes over.

  14. Cosmic Plasma Wakefield Acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Chen, P

    2004-04-26

    Recently we proposed a new cosmic acceleration mechanism which was based on the wakefields excited by the Alfven shocks in a relativistically owing plasma. In this paper we include some omitted details, and show that there exists a threshold condition for transparency below which the accelerating particle is collision-free and suffers little energy loss in the plasma medium. The stochastic encounters of the random accelerating-decelerating phases results in a power-law energy spectrum: f({epsilon}) {proportional_to} 1/{epsilon}{sup 2}. As an example, we discuss the possible production of super-GZK ultra high energy cosmic rays (UHECR) in the atmosphere of gamma ray bursts. The estimated event rate in our model agrees with that from UHECR observations.

  15. Plasma Trytophan and Sleep

    Science.gov (United States)

    Chen, C. N.; Kalucy, R. S.; Hartmann, M. K.; Lacey, J. H.; Crisp, A. H.; Bailey, J. E.; Eccleston, E. G.; Coppen, A.

    1974-01-01

    Free, bound, and total plasma tryptophan (F.P.T., B.P.T., and T.P.T.) levels have been measured throughout the night in six young female volunteers. All-night polygraphic sleep recordings were also made. No direct temporal relationship was found between plasma tryptophan levels and specific sleep stages. The mean F.P.T. levels, however, were found to have a positive correlation with rapid-eye-movement (R.E.M.) sleep and a negative correlation with non-R.E.M. sleep. An inverse relationship existed between the F.P.T. and B.P.T. levels. There appeared to be a diurnal variation in F.P.T. levels, with high readings in the first half of the night. PMID:4373116

  16. Microinstabilities in stellarator plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Rafiq, T.; Nasim, M.H.; Persson, M. [Department of Electromagnetics and Euratom/VR Association, Chalmers University of Technology, Goeteborg (Sweden)

    2003-07-01

    Linear stability and localization of ion temperature gradient modes in fully 3-dimensional stellarator plasmas is calculated in the electrostatic limit. A ballooning mode formalism with WKB assumption is applied to reduce the equations into ordinary differential equation along the field lines which are solved numerically for different plasma parameters. The results are correlated with the geometrical effects such as magnetic curvature, local magnetic shear and its integrated value along the field line and the effects of trapped electrons are also investigated. The eigenfunctions of the most unstable modes are found to be localized but the nodes in the amplitude of the eigenfunctions may be large depending upon the location on the magnetic surface. The results are compared and contrasted with calculations in tokamak geometry and the implications on future stellarator design is also discussed. (orig.)

  17. Plasma dust crystallization

    Science.gov (United States)

    Goree, John; Thomas, H.; Morfill, G.

    1994-01-01

    In a ground-based definition study, a concept for a new type of microgravity experiment is developed. We formed a new state of matter: a crystalline lattice structure of charged micron-size spheres, suspended in a charge-neutral plasma. The plasma is formed by a low-pressure radio-frequency argon discharge. Solid microspheres are introduced, and they gain a negative electric charge. They are cooled by molecular drag on the ambient neutral gas. They are detected by laser light scattering and video photography. Laboratory experiments have demonstrated that a two-dimensional nonquantum lattice forms through the Coulomb interaction of these spheres. Microgravity is thought to be required to observe a three-dimensional structure.

  18. Theoretical plasma physics

    Science.gov (United States)

    Boozer, A. H.; Vahala, G. M.

    1992-05-01

    Work during the past year in the areas of classical and anomalous transport, three-dimensional equilibria, divertor physics, and diagnostic techniques using waves is reported. Although much work was done on classical transport, the validity of the guiding-center drift equations, which are the basis of much of the theory, has received little attention. The limitations of the drift approximation are being studied. Work on three-dimensional equilibria, which shows that quasi-helical symmetry is broken in third order in the inverse aspect ratio, on the modification of the current profile due to tearing modes was completed. This work is relevant to the maintenance of a steady-state tokamak by the bootstrap current. Divertor physics is a primary area that required development for ITER. One of the few methods by which the physics of the divertor can be modified or controlled is magnetic perturbations. The effect of magnetic perturbations on the divertor scrapeoff layer in collaboration with Hampton University is being studied. The evolution of magnetic field embedded in a moving plasma is a dynamics problem of potential importance. Renormalization techniques gave important insights first in the theory of phase transitions. The applications of these techniques has extended to many areas of physics, including turbulence in fluids and plasmas. Essentially no diagnostics for magnetic fluctuations inside a fusion-grade plasma exist. A collaborative program with Old Dominion University and the Princeton Plasma Physics Laboratory to develop such a diagnostic based on the conversion of electromagnetic waves from the ordinary to the extraordinary mode is underway.

  19. Topics in Plasma Physics

    Energy Technology Data Exchange (ETDEWEB)

    Vahala, Linda [Old Dominion Univ., Norfolk, VA (United States)

    2015-05-31

    During the period 1998-2013, research under the auspices of the Department of Energy was performed on RF waves in plasmas. This research was performed in close collaboration with Josef Preinhaelter, Jakub Urban, Vladimir Fuchs, Pavol Pavlo and Frantisek Zacek (Czech Academy of Sciences), Martin Valovic and Vladimir Shevchenko (Culham). This research is detailed and all 38 papers which were published by this team are cited.

  20. Princeton Plasma Physics Laboratory:

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, C.A. (ed.)

    1986-01-01

    This paper discusses progress on experiments at the Princeton Plasma Physics Laboratory. The projects and areas discussed are: Principal Parameters Achieved in Experimental Devices, Tokamak Fusion Test Reactor, Princeton Large Torus, Princeton Beta Experiment, S-1 Spheromak, Current-Drive Experiment, X-ray Laser Studies, Theoretical Division, Tokamak Modeling, Spacecraft Glow Experiment, Compact Ignition Tokamak, Engineering Department, Project Planning and Safety Office, Quality Assurance and Reliability, and Administrative Operations.

  1. Dusty plasma (Yukawa) rings

    CERN Document Server

    Sheridan, T E

    2010-01-01

    One-dimensional and quasi-one-dimensional strongly-coupled dusty plasma rings have been created experimentally. Longitudinal (acoustic) and transverse (optical) dispersion relations for the 1-ring were measured and found to be in very good agreement with the theory for an unbounded straight chain of particles interacting through a Yukawa (i.e., screened Coulomb or Debye-H\\"uckel) potential. These rings provide a new system in which to study one-dimensional and quasi-one-dimensional physics.

  2. Plasma antioxidants from chocolate

    OpenAIRE

    Serafini, M; Bugianesi, R.; Maiani, G.; Valtuena, S.; De Santis, S.; Crozier, A.

    2003-01-01

    There is some speculation that dietary flavonoids from chocolate, in particular (-)epicatechin, may promote cardiovascular health as a result of direct antioxidant effects or through antithrombotic mechanisms. Here we show that consumption of plain, dark chocolate results in an increase in both the total antioxidant capacity and the (-)epicatechin content of blood plasma, but that these effects are markedly reduced when the chocolate is consumed with milk or if milk is incorporated as milk ch...

  3. Relativistic spherical plasma waves

    CERN Document Server

    Bulanov, S S; Schroeder, C B; Zhidkov, A G; Esarey, E; Leemans, W P

    2011-01-01

    Tightly focused laser pulses as they diverge or converge in underdense plasma can generate wake waves, having local structures that are spherical waves. Here we report on theoretical study of relativistic spherical wake waves and their properties, including wave breaking. These waves may be suitable as particle injectors or as flying mirrors that both reflect and focus radiation, enabling unique X-ray sources and nonlinear QED phenomena.

  4. Dense Plasma Focus Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hui [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Li, Shengtai [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jungman, Gerard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hayes-Sterbenz, Anna Catherine [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-31

    The mechanisms for pinch formation in Dense Plasma Focus (DPF) devices, with the generation of high-energy ions beams and subsequent neutron production over a relatively short distance, are not fully understood. Here we report on high-fidelity 2D and 3D numerical magnetohydrodynamic (MHD) simulations using the LA-COMPASS code to study the pinch formation dynamics and its associated instabilities and neutron production.

  5. Plasma Processing of Materials

    Science.gov (United States)

    1985-02-22

    used in France. In this case, three ’ movable electrodes arranged about the central axis with a coaxial sheath gas are employed. Initially the...Demiocratic Republic plasma furnace. chrome -magnesite; the bottom section is lined with rammed chrome -magnesite refractory. Due to the high heat loads... sheath injector design, cathode tip shape, and degree of water cooling are important parameters in providing a stable, uncontaminating, long-lifetime

  6. Plasma is a strategic resource.

    Science.gov (United States)

    Strengers, Paul F W; Klein, Harvey G

    2016-12-01

    Plasma-derived medicinal products (PDMPs) such as immunoglobulins and clotting factors are listed by the World Health Organization as essential medicines. These and other PDMPs are crucial for the prophylaxis and treatment of patients with bleeding disorders, immune deficiencies, autoimmune and inflammatory diseases, and a variety of congenital deficiency disorders. While changes in clinical practice in developed countries have reduced the need for red blood cell transfusions thereby significantly reducing the collection volumes of whole blood and recovered plasma suitable for fractionation, the need for PDMPs worldwide continues to increase. The majority of plasma supplies for the manufacture of PDMPs is met by the US commercial plasma industry. However, geographic imbalance in the collection of plasma raises concerns that local disruptions of plasma supplies could result in regional and global shortages of essential PDMPs. Plasma, which fits the definition of a strategic resource, that is, "an economically important raw material which is subject to a higher risk of supply interruption," should be considered a strategic resource comparable to energy and drinking water. Plasma collections should be increased outside the United States, including in low- and middle-income countries. The need for capacity building in these countries is an essential part to strengthen quality plasma collection. This will require changes in national and regional policies. We advocate the need for the restoration of an equitable balance of the international plasma supply to reduce the risk of supply shortages worldwide. Strategic independence of plasma should be endorsed on a global level. © 2016 AABB.

  7. Electrosurgical Plasma Discharges

    Science.gov (United States)

    Stalder, K. R.; Woloszko, J.

    2002-10-01

    Electrosurgical instruments employing plasmas to volumetrically ablate tissue are now enjoying widespread use in medical applications. We have studied several commercially available instruments in which luminous plasma discharges are formed near electrodes immersed in saline solutions when sufficiently large amplitude bipolar voltage waveforms are applied. Different aqueous salt solutions have been investigated, including isotonic NaCl solution as well as solutions of KCl, and BaCl_2. With strong driving voltage applied, a vapor layer is formed as well as visible and UV optical emissions. Spectroscopic measurements reveal the predominant emissions are from the low ionization potential salt species, but significant emissions from electron impact dissociated water fragments such as OH and H-atoms also are observed. The emissions also coincide with negative bias on the active electrode. These optical emissions are consistent with an electron density of about 10^12cm-3 and an electron temperature of about 4 eV. Experimental results and model calculations of the vapor layer formation process and plasma formation in the high-field region will be discussed.

  8. Plasma Modeling of Electrosurgery

    Science.gov (United States)

    Jensen, Scott; Friedrichs, Daniel; Gilbert, James; Park, Wounjhang; Maksimovic, Dragan

    2014-10-01

    Electrosurgery is the use of high frequency alternating current (AC) to illicit a clinical response in tissue, such as cutting or cauterization. Power electronics converters have been demonstrated to generate the necessary output voltage and current for electrosurgery. The design goal of the converter is to regulate output power while supplying high frequency AC. The design is complicated by fast current and voltage transients that occur when the current travels through air in the form of an arc. To assist in designing a converter that maintains the desired output power during these transients, we have used the COMSOL Plasma Module to determine the output voltage and current characteristics during an arc. This plasma model, used in conjunction with linear circuit elements, allows the full electrosurgical system to be validated. Two models have been tested with the COMSOL Plasma Module. One is a four-species, four-reaction model based on the local field approximation technique. The second simulates the underlying air chemistry using 30 species, 151 chemical reactions, and a coupled electron energy distribution function. Experimental output voltage and current samples have been collected and compared to both models.

  9. Sterilization by oxygen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Adir Jose; Mansano, Ronaldo Domingues; Andreoli Pinto, Terezinha de Jesus; Ruas, Ronaldo; Silva Zambon, Luis da; Silva, Monica Valero da; Verdonck, Patrick Bernard

    2004-07-31

    The use of polymeric medical devices has stimulated the development of new sterilization methods. The traditional techniques rely on ethylene oxide, but there are many questions concerning the carcinogenic properties of the ethylene oxide residues adsorbed on the materials after processing. Another common technique is the gamma irradiation process, but it is costly, its safe operation requires an isolated site and it also affects the bulk properties of the polymers. The use of a gas plasma is an elegant alternative sterilization technique. The plasma promotes an efficient inactivation of the micro-organisms, minimises the damage to the materials and presents very little danger for personnel and the environment. Pure oxygen reactive ion etching type of plasmas were applied to inactivate a biologic indicator, the Bacillus stearothermophilus, to confirm the efficiency of this process. The sterilization processes took a short time, in a few minutes the mortality was complete. In situ analysis of the micro-organisms' inactivating time was possible using emission spectrophotometry. The increase in the intensity of the 777.5 nm oxygen line shows the end of the oxidation of the biologic materials. The results were also observed and corroborated by scanning electron microscopy.

  10. Modeling electronegative plasma discharge

    Energy Technology Data Exchange (ETDEWEB)

    Lichtenberg, A.J.; Lieberman, M.A. [Univ. of California, Berkley, CA (United States)

    1995-12-31

    Macroscopic analytic models for a three-component electronegative gas discharge are developed. Assuming the negative ions to be in Boltzmann equilibrium, a positive ion ambipolar diffusion equation is derived. The discharge consists of an electronegative core and electropositive edges. The electron density in the core is nearly uniform, allowing a parabolic approximation to the plasma profile to be employed. The resulting equilibrium equations are solved analytically and matched to a constant mobility transport model of an electropositive edge plasma. The solutions are compared to a simulation of a parallel-plane r.f. driven oxygen plasma for p = 50 mTorr and n{sub eo}= 2.4 x 10{sup 15} m{sup -3}. The ratio {alpha}{sub o} of central negative ion density to electron density, and the electron temperature T{sub e}, found in the simulation, are in reasonable agreement with the values calculated from the model. The model is extended to: (1) low pressures, where a variable mobility model is used in the electropositive edge region; and (2) high {alpha}{sub o} in which the edge region disappears. The inclusion of a second positive ion species, which can be very important in describing electronegative discharges used for materials processing, is a possible extension of the model.

  11. PLASMA CELL LEUKEMIA

    Science.gov (United States)

    de Larrea, Carlos Fernandez; Kyle, Robert A.; Durie, Brian GM; Ludwig, Heinz; Usmani, Saad; Vesole, David H.; Hajek, Roman; Miguel, Jésus San; Sezer, Orhan; Sonneveld, Pieter; Kumar, Shaji K.; Mahindra, Anuj; Comenzo, Ray; Palumbo, Antonio; Mazumber, Amitabha; Anderson, Kenneth C.; Richardson, Paul G.; Badros, Ashraf Z.; Caers, Jo; Cavo, Michele; LeLeu, Xavier; Dimopoulos, Meletios A.; Chim, CS; Schots, Rik; Noeul, Amara; Fantl, Dorotea; Mellqvist, Ulf-Henrik; Landgren, Ola; Chanan-Khan, Asher; Moreau, Philippe; Fonseca, Rafael; Merlini, Giampaolo; Lahuerta, JJ; Bladé, Joan; Orlowski, Robert Z.; Shah, Jatin J.

    2014-01-01

    Plasma cell leukemia (PCL) is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells. It is classified as either primary PCL occurring at diagnosis or as secondary PCL in patients with relapsed/refractory myeloma. Primary PCL is a distinct clinic-pathologic entity with different cytogenetic and molecular findings. The clinical course is aggressive with short remissions and survival duration. The diagnosis is based upon the percentage (≥ 20%) and absolute number (≥ 2 × 10 9/L) of plasma cells in the peripheral blood. It is proposed that the thresholds for diagnosis be reexamined and consensus recommendations are made for diagnosis, as well as, response and progression criteria. Induction therapy needs to begin promptly and have high clinical activity leading to rapid disease control in an effort to minimize the risk of early death. Intensive chemotherapy regimens and bortezomib-based regimens are recommended followed by high-dose therapy with autologous stem-cell transplantation (HDT/ASCT) if feasible. Allogeneic transplantation can be considered in younger patients. Prospective multicenter studies are required to provide revised definitions and better understanding of the pathogenesis of PCL. PMID:23288300

  12. Electron waves and resonances in bounded plasmas

    CERN Document Server

    Vandenplas, Paul E

    1968-01-01

    General theoretical methods and experimental techniques ; the uniform plasma slab-condenser system ; the hollow cylindrical plasma ; scattering of a plane electromagnetic wave by a plasma column in steady magnetic fields (cold plasma approximation) ; hot non-uniform plasma column ; metallic and dielectric resonance probes, plasma-dielectric coated antenna, general considerations.

  13. Proton driven plasma wakefield generation in a parabolic plasma channel

    Science.gov (United States)

    Golian, Y.; Dorranian, D.

    2016-11-01

    An analytical model for the interaction of charged particle beams and plasma for a wakefield generation in a parabolic plasma channel is presented. In the suggested model, the plasma density profile has a minimum value on the propagation axis. A Gaussian proton beam is employed to excite the plasma wakefield in the channel. While previous works investigated on the simulation results and on the perturbation techniques in case of laser wakefield accelerations for a parabolic channel, we have carried out an analytical model and solved the accelerating field equation for proton beam in a parabolic plasma channel. The solution is expressed by Whittaker (hypergeometric) functions. Effects of plasma channel radius, proton bunch parameters and plasma parameters on the accelerating processes of proton driven plasma wakefield acceleration are studied. Results show that the higher accelerating fields could be generated in the PWFA scheme with modest reductions in the bunch size. Also, the modest increment in plasma channel radius is needed to obtain maximum accelerating gradient. In addition, the simulations of longitudinal and total radial wakefield in parabolic plasma channel are presented using LCODE. It is observed that the longitudinal wakefield generated by the bunch decreases with the distance behind the bunch while total radial wakefield increases with the distance behind the bunch.

  14. Plasma Torch for Plasma Ignition and Combustion of Coal

    Science.gov (United States)

    Ustimenko, Alexandr; Messerle, Vladimir

    2015-09-01

    Plasma-fuel systems (PFS) have been developed to improve coal combustion efficiency. PFS is a pulverized coal burner equipped with arc plasma torch producing high temperature air stream of 4000 - 6000 K. Plasma activation of coal at the PFS increases the coal reactivity and provides more effective ignition and ecologically friendly incineration of low-rank coal. The main and crucial element of PFS is plasma torch. Simplicity and reliability of the industrial arc plasma torches using cylindrical copper cathode and air as plasma forming gas predestined their application at heat and power engineering for plasma aided coal combustion. Life time of these plasma torches electrodes is critical and usually limited to 200 hours. Considered in this report direct current arc plasma torch has the cathode life significantly exceeded 1000 hours. To ensure the electrodes long life the process of hydrocarbon gas dissociation in the electric arc discharge is used. In accordance to this method atoms and ions of carbon from near-electrode plasma deposit on the active surface of the electrodes and form electrode carbon condensate which operates as ``actual'' electrode. Complex physicochemical investigation showed that deposit consists of nanocarbon material.

  15. Genetic Architecture of Plasma Adiponectin Overlaps With the Genetics of Metabolic Syndrome–Related Traits

    Science.gov (United States)

    Henneman, Peter; Aulchenko, Yurii S.; Frants, Rune R.; Zorkoltseva, Irina V.; Zillikens, M. Carola; Frolich, Marijke; Oostra, Ben A.; van Dijk, Ko Willems; van Duijn, Cornelia M.

    2010-01-01

    OBJECTIVE Adiponectin, a hormone secreted by adipose tissue, is of particular interest in metabolic syndrome, because it is inversely correlated with obesity and insulin sensitivity. However, it is not known to what extent the genetics of plasma adiponectin and the genetics of obesity and insulin sensitivity are interrelated. We aimed to evaluate the heritability of plasma adiponectin and its genetic correlation with the metabolic syndrome and metabolic syndrome–related traits and the association between these traits and 10 ADIPOQ single nucleotide polymorphisms (SNPs). RESEARCH DESIGN AND METHODS We made use of a family-based population, the Erasmus Rucphen Family study (1,258 women and 967 men). Heritability analysis was performed using a polygenic model. Genetic correlations were estimated using bivariate heritability analyses. Genetic association analysis was performed using a mixed model. RESULTS Plasma adiponectin showed a heritability of 55.1%. Genetic correlations between plasma adiponectin HDL cholesterol and plasma insulin ranged from 15 to 24% but were not significant for fasting glucose, triglycerides, blood pressure, homeostasis model assessment of insulin resistance (HOMA-IR), and C-reactive protein. A significant association with plasma adiponectin was found for ADIPOQ variants rs17300539 and rs182052. A nominally significant association was found with plasma insulin and HOMA-IR and ADIPOQ variant rs17300539 after adjustment for plasma adiponectin. CONCLUSIONS The significant genetic correlation between plasma adiponectin and HDL cholesterol and plasma insulin should be taken into account in the interpretation of genome-wide association studies. Association of ADIPOQ SNPs with plasma adiponectin was replicated, and we showed association between one ADIPOQ SNP and plasma insulin and HOMA-IR. PMID:20067957

  16. Acinetobacter baumannii secretes cytotoxic outer membrane protein A via outer membrane vesicles.

    Directory of Open Access Journals (Sweden)

    Jong Sook Jin

    Full Text Available Acinetobacter baumannii is an important nosocomial pathogen that causes a high morbidity and mortality rate in infected patients, but pathogenic mechanisms of this microorganism regarding the secretion and delivery of virulence factors to host cells have not been characterized. Gram-negative bacteria naturally secrete outer membrane vesicles (OMVs that play a role in the delivery of virulence factors to host cells. A. baumannii has been shown to secrete OMVs when cultured in vitro, but the role of OMVs in A. baumannii pathogenesis is not well elucidated. In the present study, we evaluated the secretion and delivery of virulence factors of A. baumannii to host cells via the OMVs and assessed the cytotoxic activity of outer membrane protein A (AbOmpA packaged in the OMVs. A. baumannii ATCC 19606(T secreted OMVs during in vivo infection as well as in vitro cultures. Potential virulence factors, including AbOmpA and tissue-degrading enzymes, were associated with A. baumannii OMVs. A. baumannii OMVs interacted with lipid rafts in the plasma membranes and then delivered virulence factors to host cells. The OMVs from A. baumannii ATCC 19606(T induced apoptosis of host cells, whereas this effect was not detected in the OMVs from the ΔompA mutant, thereby reflecting AbOmpA-dependent host cell death. The N-terminal region of AbOmpA(22-170 was responsible for host cell death. In conclusion, the OMV-mediated delivery of virulence factors to host cells may well contribute to pathogenesis during A. baumannii infection.

  17. Lipids and lipid binding proteins: a perfect match.

    Science.gov (United States)

    Glatz, Jan F C

    2015-02-01

    Lipids serve a great variety of functions, ranging from structural components of biological membranes to signaling molecules affecting various cellular functions. Several of these functions are related to the unique physico-chemical properties shared by all lipid species, i.e., their hydrophobicity. The latter, however, is accompanied by a poor solubility in an aqueous environment and thus a severe limitation in the transport of lipids in aqueous compartments such as blood plasma and the cellular soluble cytoplasm. Specific proteins which can reversibly and non-covalently associate with lipids, designated as lipid binding proteins or lipid chaperones, greatly enhance the aqueous solubility of lipids and facilitate their transport between tissues and within tissue cells. Importantly, transport of lipids across biological membranes also is facilitated by specific (membrane-associated) lipid binding proteins. Together, these lipid binding proteins determine the bio-availability of their ligands, and thereby markedly influence the subsequent processing, utilization, or signaling effect of lipids. The bio-availability of specific lipid species thus is governed by the presence of specific lipid binding proteins, the affinity of these proteins for distinct lipid species, and the presence of competing ligands (including pharmaceutical compounds). Recent studies suggest that post-translational modifications of lipid binding proteins may have great impact on lipid-protein interactions. As a result, several levels of regulation exist that together determine the bio-availability of lipid species. This short review discusses the significance of lipid binding proteins and their potential application as targets for therapeutic intervention.

  18. Extracellular heat shock proteins: a new location, a new function.

    Science.gov (United States)

    De Maio, Antonio; Vazquez, Daniel

    2013-10-01

    The expression of heat shock proteins (HSPs) is a basic and well-conserved cellular response to an array of stresses. These proteins are involved in the repair of cellular damage induced by the stress, which is necessary for the salutary resolution from the insult. Moreover, they confer protection from subsequent insults, which has been coined stress tolerance. Because these proteins are expressed in subcellular compartments, it was thought that their function during stress conditions was circumscribed to the intracellular environment. However, it is now well established that HSPs can also be present outside cells where they appear to display a function different than the well-understood chaperone role. Extracellular HSPs act as alert stress signals priming other cells, particularly of the immune system, to avoid the propagation of the insult and favor resolution. Because the majority of HSPs do not possess a secretory peptide signal, they are likely to be exported by a nonclassic secretory pathway. Different mechanisms have been proposed to explain the export of HSPs, including translocation across the plasma membrane and release associated with lipid vesicles, as well as the passive release after cell death by necrosis. Extracellular HSPs appear in various flavors, including membrane-bound and membrane-free forms. All of these variants of extracellular HSPs suggest that their interactions with cells may be quite diverse, both in target cell types and the activation signaling pathways. This review addresses some of our current knowledge about the release and relevance of extracellular HSPs.

  19. Online plasma diagnostics of a laser-produced plasma

    Science.gov (United States)

    Kai, Gao; Nasr, A. M. Hafz; Song, Li; Mohammad, Mirzaie; Guangyu, Li; Quratul, Ain

    2017-01-01

    In this study, we report a laser interferometry experiment for the online-diagnosing of a laser-produced plasma. The laser pulses generating the plasma are ultra-fast (30 femtoseconds), ultra-intense (tens of Terawatt) and are focused on a helium gas jet to generate relativistic electron beams via the laser wakefield acceleration (LWFA) mechanism. A probe laser beam (λ = 800 nm) which is split-off the main beam is used to cross the plasma at the time of arrival of the main pulse, allowing online plasma density diagnostics. The interferometer setup is based on the NoMarski method in which we used a Fresnel bi-prism where the probe beam interferes with itself after crossing the plasma medium. A high-dynamic range CCD camera is used to record the interference patterns. Based upon the Abel inversion technique, we obtained a 3D density distribution of the plasma density.

  20. Clinical use of Plasma and Plasma Fractions in Bleeding Disorders

    Institute of Scientific and Technical Information of China (English)

    王兆钺

    2008-01-01

    Internal and/or external bleeding is a common and sometimes very severe clinical manifestations of disorders of hemostasis. It may follow minor trauma or may arise apparently spontaneously. Disorders of hemostasis are generally divided into those caused by abnormalities of platelets, abnormalities of blood vessels, abnormalities of plasma coagulation factors, and hyperfibrinolysis, or com-binations of these. The use of plasma and plasma fractions dependents on the causing diseases and their severity. Several plasma products and plasma fractions are availa-ble in China and other plasma components and deriva-tives are commercially obtained. There have been the guidelines for their clinical use, and the revised ones will soon be published by Chinese Medical Association.

  1. Abelianization of QCD plasma instabilities

    Science.gov (United States)

    Arnold, Peter; Lenaghan, Jonathan

    2004-12-01

    QCD plasma instabilities appear to play an important role in the equilibration of quark-gluon plasmas in heavy-ion collisions in the theoretical limit of weak coupling (i.e. asymptotically high energy). It is important to understand what nonlinear physics eventually stops the exponential growth of unstable modes. It is already known that the initial growth of plasma instabilities in QCD closely parallels that in QED. However, once the unstable modes of the gauge fields grow large enough for non-Abelian interactions between them to become important, one might guess that the dynamics of QCD plasma instabilities and QED plasma instabilities become very different. In this paper, we give suggestive arguments that non-Abelian self-interactions between the unstable modes are ineffective at stopping instability growth, and that the growing non-Abelian gauge fields become approximately Abelian after a certain stage in their growth. This in turn suggests that understanding the development of QCD plasma instabilities in the nonlinear regime may have close parallels to similar processes in traditional plasma physics. We conjecture that the physics of collisionless plasma instabilities in SU(2) and SU(3) gauge theory becomes equivalent, respectively, to (i) traditional plasma physics, which is U(1) gauge theory, and (ii) plasma physics of U(1)×U(1) gauge theory.

  2. The diverse applications of plasma

    Science.gov (United States)

    Sharma, Mukul; Dubey, Shivani; Darwhekar, Gajanan; Jain, Sudhir Kumar

    2015-07-01

    Plasma being the fourth state of matter has always been an attraction for Physicists and Chemists. With the advent of time, plasma energy has been recognized in having widening horizons in the field of Biomedical Sciences. Plasma medicine can be subdivided into three main fields; Non-thermal atmospheric-pressure direct plasma for medical therapy; Plasma-assisted modification of bio-relevant surfaces and Plasma-based bio-decontamination and sterilization. The basis of the research is that as it has free carrier molecules, it has the ability to target specific cells and regulate functions like wound healing. Plasma does not harm healthy human cells but can kill bacteria and possibly even cancer cells to help treat various diseases. Nosocomial infection control, prevention and containment of contagious diseases, disinfection of medical devices, surface treatment (heat and UV sensitive surfaces) are research of interest. Recent success in generating plasma at very low temperature ie. Cold plasma makes the therapy painless. It has the ability to activate cellular responses and important mechanisms in the body. They target specific molecules such as prothrombin for blood coagulation, cytokines for killing bacteria, and angiogenesis for tissue regeneration. Plasma has bactericidal, fungicidal and virucidal properties. Plasma technology has flourishing future in diverse fields like Textiles, Nanofabrication, Automotives, Waste management, Microbiology, Food Hygiene, Medical Science like Skin treatments, sterilisation of wounds, Hand disinfection, Dental treatments etc. Food hygiene using plasma can be achieved in disinfection of food containers, food surface disinfection, hygiene in food handling, preparation and packaging. Therefore Plasma is most promising field for budding Scientist for fluorishing research in Biological Sciences.

  3. The diverse applications of plasma

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Mukul, E-mail: mukulsharma@acropolis.edu.in; Darwhekar, Gajanan, E-mail: gdarwhekar@acropolis.edu.in [Acropolis Institute of Pharmaceutical Education & Research, Indore MP India (India); Dubey, Shivani, E-mail: dubeyshivani08@rediffmail.com [Mata Gujri College of Professional Studies, Indore MP India (India); Jain, Sudhir Kumar, E-mail: sudhirkjain1@rediffmail.com [School of Studies in Microbiology, Vikram University, Ujjain MP India (India)

    2015-07-31

    Plasma being the fourth state of matter has always been an attraction for Physicists and Chemists. With the advent of time, plasma energy has been recognized in having widening horizons in the field of Biomedical Sciences. Plasma medicine can be subdivided into three main fields; Non-thermal atmospheric-pressure direct plasma for medical therapy; Plasma-assisted modification of bio-relevant surfaces and Plasma-based bio-decontamination and sterilization. The basis of the research is that as it has free carrier molecules, it has the ability to target specific cells and regulate functions like wound healing. Plasma does not harm healthy human cells but can kill bacteria and possibly even cancer cells to help treat various diseases. Nosocomial infection control, prevention and containment of contagious diseases, disinfection of medical devices, surface treatment (heat and UV sensitive surfaces) are research of interest. Recent success in generating plasma at very low temperature ie. Cold plasma makes the therapy painless. It has the ability to activate cellular responses and important mechanisms in the body. They target specific molecules such as prothrombin for blood coagulation, cytokines for killing bacteria, and angiogenesis for tissue regeneration. Plasma has bactericidal, fungicidal and virucidal properties. Plasma technology has flourishing future in diverse fields like Textiles, Nanofabrication, Automotives, Waste management, Microbiology, Food Hygiene, Medical Science like Skin treatments, sterilisation of wounds, Hand disinfection, Dental treatments etc. Food hygiene using plasma can be achieved in disinfection of food containers, food surface disinfection, hygiene in food handling, preparation and packaging. Therefore Plasma is most promising field for budding Scientist for fluorishing research in Biological Sciences.

  4. Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

    Science.gov (United States)

    2013-10-01

    sensitive surfaces. In this paper, the consumed power for plasma generation (plasma power) has been estimated from voltage-current waveform analysis in... consumed power for plasma generation is calculated by integrating the product of the discharge voltage and current over one cycle; according to the...Faculty Symposium: Course Design for the Millennial Student, Texas A&M University – Corpus Christi, 2011. (Showcased by the Center for Faculty

  5. Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

    Science.gov (United States)

    2015-12-01

    research associates. The PI and the research team have published over 10 journal articles and over 50 conference proceedings and over 50 symposiums...reflections. Optical interference filters with center wavelength at 5322 or 632.82 nm are used in front of the ICCD to suppress the plasma self- luminescence ...wavelength at 532 ± 2 nm was used in front of the ICCD to suppress the plasma jet self- luminescence . The shadow of the laser induced plasma falls onto

  6. A contoured gap coaxial plasma gun with injected plasma armature

    Science.gov (United States)

    Witherspoon, F. Douglas; Case, Andrew; Messer, Sarah J.; Bomgardner, Richard; Phillips, Michael W.; Brockington, Samuel; Elton, Raymond

    2009-08-01

    A new coaxial plasma gun is described. The long term objective is to accelerate 100-200 μg of plasma with density above 1017 cm-3 to greater than 200 km/s with a Mach number above 10. Such high velocity dense plasma jets have a number of potential fusion applications, including plasma refueling, magnetized target fusion, injection of angular momentum into centrifugally confined mirrors, high energy density plasmas, and others. The approach uses symmetric injection of high density plasma into a coaxial electromagnetic accelerator having an annular gap geometry tailored to prevent formation of the blow-by instability. The injected plasma is generated by numerous (currently 32) radially oriented capillary discharges arranged uniformly around the circumference of the angled annular injection region of the accelerator. Magnetohydrodynamic modeling identified electrode profiles that can achieve the desired plasma jet parameters. The experimental hardware is described along with initial experimental results in which approximately 200 μg has been accelerated to 100 km/s in a half-scale prototype gun. Initial observations of 64 merging injector jets in a planar cylindrical testing array are presented. Density and velocity are presently limited by available peak current and injection sources. Steps to increase both the drive current and the injected plasma mass are described for next generation experiments.

  7. A contoured gap coaxial plasma gun with injected plasma armature.

    Science.gov (United States)

    Witherspoon, F Douglas; Case, Andrew; Messer, Sarah J; Bomgardner, Richard; Phillips, Michael W; Brockington, Samuel; Elton, Raymond

    2009-08-01

    A new coaxial plasma gun is described. The long term objective is to accelerate 100-200 microg of plasma with density above 10(17) cm(-3) to greater than 200 km/s with a Mach number above 10. Such high velocity dense plasma jets have a number of potential fusion applications, including plasma refueling, magnetized target fusion, injection of angular momentum into centrifugally confined mirrors, high energy density plasmas, and others. The approach uses symmetric injection of high density plasma into a coaxial electromagnetic accelerator having an annular gap geometry tailored to prevent formation of the blow-by instability. The injected plasma is generated by numerous (currently 32) radially oriented capillary discharges arranged uniformly around the circumference of the angled annular injection region of the accelerator. Magnetohydrodynamic modeling identified electrode profiles that can achieve the desired plasma jet parameters. The experimental hardware is described along with initial experimental results in which approximately 200 microg has been accelerated to 100 km/s in a half-scale prototype gun. Initial observations of 64 merging injector jets in a planar cylindrical testing array are presented. Density and velocity are presently limited by available peak current and injection sources. Steps to increase both the drive current and the injected plasma mass are described for next generation experiments.

  8. Electron density and plasma dynamics of a colliding plasma experiment

    Energy Technology Data Exchange (ETDEWEB)

    Wiechula, J., E-mail: wiechula@physik.uni-frankfurt.de; Schönlein, A.; Iberler, M.; Hock, C.; Manegold, T.; Bohlender, B.; Jacoby, J. [Plasma Physics Group, Institute of Applied Physics, Goethe University, 60438 Frankfurt am Main (Germany)

    2016-07-15

    We present experimental results of two head-on colliding plasma sheaths accelerated by pulsed-power-driven coaxial plasma accelerators. The measurements have been performed in a small vacuum chamber with a neutral-gas prefill of ArH{sub 2} at gas pressures between 17 Pa and 400 Pa and load voltages between 4 kV and 9 kV. As the plasma sheaths collide, the electron density is significantly increased. The electron density reaches maximum values of ≈8 ⋅ 10{sup 15} cm{sup −3} for a single accelerated plasma and a maximum value of ≈2.6 ⋅ 10{sup 16} cm{sup −3} for the plasma collision. Overall a raise of the plasma density by a factor of 1.3 to 3.8 has been achieved. A scaling behavior has been derived from the values of the electron density which shows a disproportionately high increase of the electron density of the collisional case for higher applied voltages in comparison to a single accelerated plasma. Sequences of the plasma collision have been taken, using a fast framing camera to study the plasma dynamics. These sequences indicate a maximum collision velocity of 34 km/s.

  9. Plasma Beam Measurements

    Science.gov (United States)

    1991-08-01

    GUN PLASMA BEAM / ,I 21 cm diameter = 0 GLASS DRIFT TUBE 50 cm diameter MCP CAMERA CLASS CROSSES (a) Gun muzzle /"- PLASA BEAM / TAROT z = 10 m MCP...discusses some of the hydrodynamic issues related to the calcula- tions. The reader may well wonder why hydrodynamics should be an issue in a 116 WL-TR-90...answer is yes for the slow beam cases and no for the fast beam cases. This is explained further. 118 WL-TR-90-83 The reader will recall the

  10. Flexible plasma linear antenna

    Science.gov (United States)

    Zhao, Jiansen; Wang, Shengzheng; Wu, Huafeng; Liu, Yue; Chang, Yongmeng; Chen, Xinqiang

    2017-02-01

    In this work, we introduce a type of plasma antenna that was fabricated using flexible materials and excited using a 5-20 kHz alternating current (ac) power supply. The results showed that the antenna characteristics, including the impedance, the reflection coefficient (S11), the radiation pattern, and the gain, can be controlled rapidly and easily by varying both the discharge parameters and the antenna shapes. The scope for reconfiguration is greatly enhanced when the antenna shape is changed from a monopole to a helix configuration. Additionally, the antenna polarization can also be adjusted by varying the antenna shapes.

  11. Chemostimulatory protein: a new type of taste stimulus.

    Science.gov (United States)

    Cagan, R H

    1973-07-06

    Three taste-active proteins have recently been discovered. It is proposed that two of these (monellin and thaumatin) should be classified as chemostimulatory proteins because of their sensory effect; these two proteins taste intensely sweet. The third protein (miraculin), a taste-modifier protein, changes the normal sour taste of acids to sweet. The taste-modifier protein, miraculin, occurs in the fruit of the tropical plant Synsepalum dulcificum. Though itself not sweet, it is able to change the taste of acids from sour to sweet after the tongue has been treated with the protein. Miraculin is a basic glycoprotein with a molecular weight of 44,000. Monellin, a chemostimulatory protein, is found in the fruit of a different tropical plant, Dioscoreophyllum cumminsii. It has been characterized as a basic protein with a molecular weight of 10,700 that contains no carbohydrate. Thaumatin, another chemostimulatory protein, occurs in the fruit of a third tropical plant, Thaumatococcus daniellii. Like monellin, it is a basic protein that contains no carbohydrate. Its molecular weight is around 21,000. Certain gross similarities among the three proteins have been noted. Their basic ionic character and some features of the amino acid compositions are similar. Little is known of the structural features of the chemostimulatory proteins that are required for eliciting their intense sweetness; they are of the order of 10(5) times more effective than sucrose. The precise role of the tertiary structure in their biological activity is not known but appears to be an important area for further study. The relatively large size (11,000 to 21,000 molecular weight) of the chemostimulatory proteins provides indirect evidence that the initial interaction of these stimuli with taste receptor cells occurs at the plasma membrane.

  12. The control of TCV plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Lister, J.B.; Hofmann, F.; Moret, J.M. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)] [and others

    1996-07-01

    The general control of tokamak plasmas has evolved considerably over the last few years with an increase in the plasma pulse length, an increase in the control of additional heating and fuelling and an increase in the degree to which the shape of the plasma can be varied. The TCV tokamak is specifically designed to explore the operational benefits of plasma shaping over a wide variety of plasma shapes. Consequently, considerable attention has been given to the control of the poloidal field coil currents which impose the desired shape. This paper deals with all aspects of the control of TCV plasmas, from the diagnostic measurements to the power supplies, via control algorithms and overall supervision. (author) 44 figs., tabs., 25 refs.

  13. MHD simulations of Plasma Jets and Plasma-surface interactions in Coaxial Plasma Accelerators

    Science.gov (United States)

    Subramaniam, Vivek; Raja, Laxminarayan

    2016-10-01

    Coaxial plasma accelerators belong to a class of electromagnetic acceleration devices which utilize a self-induced Lorentz force to accelerate magnetized thermal plasma to large velocities ( 40 Km/s). The plasma jet generated as a result, due to its high energy density, can be used to mimic the plasma-surface interactions at the walls of thermonuclear fusion reactors during an Edge Localized Mode (ELM) disruption event. We present the development of a Magnetohydrodynamics (MHD) simulation tool to describe the plasma acceleration and jet formation processes in coaxial plasma accelerators. The MHD model is used to study the plasma-surface impact interaction generated by the impingement of the jet on a target material plate. The study will characterize the extreme conditions generated on the target material surface by resolving the magnetized shock boundary layer interaction and the viscous/thermal diffusion effects. Additionally, since the plasma accelerator is operated in vacuum conditions, a novel plasma-vacuum interface tracking algorithm is developed to simulate the expansion of the high density plasma into a vacuum background in a physically consistent manner.

  14. Plasma diagnostics discharge parameters and chemistry

    CERN Document Server

    Auciello, Orlando

    1989-01-01

    Plasma Diagnostics, Volume 1: Discharge Parameters and Chemistry covers seven chapters on the important diagnostic techniques for plasmas and details their use in particular applications. The book discusses optical diagnostic techniques for low pressure plasmas and plasma processing; plasma diagnostics for electrical discharge light sources; as well as Langmuir probes. The text also describes the mass spectroscopy of plasmas, microwave diagnostics, paramagnetic resonance diagnostics, and diagnostics in thermal plasma processing. Electrical engineers, nuclear engineers, microwave engineers, che

  15. Plasma Sources for Medical Applications - A Comparison of Spot Like Plasmas and Large Area Plasmas

    Science.gov (United States)

    Weltmann, Klaus-Dieter

    2015-09-01

    Plasma applications in life science are currently emerging worldwide. Whereas today's commercially available plasma surgical technologies such as argon plasma coagulation (APC) or ablation are mainly based on lethal plasma effects on living systems, the newly emerging therapeutic applications will be based on selective, at least partially non-lethal, possibly stimulating plasma effects on living cells and tissue. Promising results could be obtained by different research groups worldwide revealing a huge potential for the application of low temperature atmospheric pressure plasma in fields such as tissue engineering, healing of chronic wounds, treatment of skin diseases, tumor treatment based on specific induction of apoptotic processes, inhibition of biofilm formation and direct action on biofilms or treatment of dental diseases. The development of suitable and reliable plasma sources for the different therapies requires an in-depth knowledge of their physics, chemistry and parameters. Therefore much basic research still needs to be conducted to minimize risk and to provide a scientific fundament for new plasma-based medical therapies. It is essential to perform a comprehensive assessment of physical and biological experiments to clarify minimum standards for plasma sources for applications in life science and for comparison of different sources. One result is the DIN-SPEC 91315, which is now open for further improvements. This contribution intends to give an overview on the status of commercial cold plasma sources as well as cold plasma sources still under development for medical use. It will discuss needs, prospects and approaches for the characterization of plasmas from different points of view. Regarding the manageability in everyday medical life, atmospheric pressure plasma jets (APPJ) and dielectric barrier discharges (DBD) are of special interest. A comprehensive risk-benefit assessment including the state of the art of commercial sources for medical use

  16. Plasma cell granuloma of lip

    Directory of Open Access Journals (Sweden)

    B Sabarinath

    2012-01-01

    Full Text Available Plasma cells are medium-sized round-to-oval cells with eccentrically placed nuclei, usually found in the red pulp of the spleen, tonsils, medulla of the lymph nodes, nasal mucosa, upper airway, lamina propria of the gastrointestinal tract, and sites of inflammation. Plasma cell granuloma is a rare reactive tumor-like proliferation composed chiefly of plasmacytic infiltrate. Here, we present a case of plasma cell granuloma of lip in a female patient.

  17. Supersonic Plasma Flow Control Experiments

    Science.gov (United States)

    2005-12-01

    to liquid metals , for example, the conductivities of typical plasma and electrolyte flows are relatively low. Ref. 14 cites the conductivity of...heating is the dominant effect. 15. SUBJECT TERMS Supersonic, plasma , MHD , boundary-layer 16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE...horns in operation on Mach 5 wind tunnel with a plasma discharge. 31 Figure 17 Front view of a 100 mA DC discharge generated with upstream pointing

  18. Computational Methods in Plasma Physics

    CERN Document Server

    Jardin, Stephen

    2010-01-01

    Assuming no prior knowledge of plasma physics or numerical methods, Computational Methods in Plasma Physics covers the computational mathematics and techniques needed to simulate magnetically confined plasmas in modern magnetic fusion experiments and future magnetic fusion reactors. Largely self-contained, the text presents the basic concepts necessary for the numerical solution of partial differential equations. Along with discussing numerical stability and accuracy, the author explores many of the algorithms used today in enough depth so that readers can analyze their stability, efficiency,

  19. Effect of cold atmospheric pressure He-plasma jet on DNA change and mutation

    Energy Technology Data Exchange (ETDEWEB)

    Yaopromsiri, C. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@thep-center.org [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Sarapirom, S. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Faculty of Science, Maejo University, Bang Khen, Chiang Mai 50290 (Thailand); Thopan, P.; Boonyawan, D. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2015-12-15

    Cold atmospheric pressure plasma jet (CAPPJ) effect on DNA change was studied for assessment of its safety. The experiment utilized a home-developed CAPPJ using 100% helium to directly treat naked DNA plasmid pGFP (plasmid green fluorescent protein). A traversal electric field was applied to separate the plasma components and both dry and wet sample conditions were adopted to investigate various factor roles in changing DNA. Plasma species were measured by using optical emission spectroscopy. DNA topological form change was analyzed by gel electrophoresis. The plasma jet treated DNA was transferred into bacterial Escherichia coli cells for observing mutation. The results show that the He-CAPPJ could break DNA strands due to actions from charge, radicals and neutrals and potentially cause genetic modification of living cells.

  20. Effect of cold atmospheric pressure He-plasma jet on DNA change and mutation

    Science.gov (United States)

    Yaopromsiri, C.; Yu, L. D.; Sarapirom, S.; Thopan, P.; Boonyawan, D.

    2015-12-01

    Cold atmospheric pressure plasma jet (CAPPJ) effect on DNA change was studied for assessment of its safety. The experiment utilized a home-developed CAPPJ using 100% helium to directly treat naked DNA plasmid pGFP (plasmid green fluorescent protein). A traversal electric field was applied to separate the plasma components and both dry and wet sample conditions were adopted to investigate various factor roles in changing DNA. Plasma species were measured by using optical emission spectroscopy. DNA topological form change was analyzed by gel electrophoresis. The plasma jet treated DNA was transferred into bacterial Escherichia coli cells for observing mutation. The results show that the He-CAPPJ could break DNA strands due to actions from charge, radicals and neutrals and potentially cause genetic modification of living cells.

  1. Autoresonant Excitation of Antiproton Plasmas

    Science.gov (United States)

    Andresen, G. B.; Ashkezari, M. D.; Baquero-Ruiz, M.; Bertsche, W.; Bowe, P. D.; Butler, E.; Carpenter, P. T.; Cesar, C. L.; Chapman, S.; Charlton, M.; Fajans, J.; Friesen, T.; Fujiwara, M. C.; Gill, D. R.; Hangst, J. S.; Hardy, W. N.; Hayden, M. E.; Humphries, A. J.; Hurt, J. L.; Hydomako, R.; Jonsell, S.; Madsen, N.; Menary, S.; Nolan, P.; Olchanski, K.; Olin, A.; Povilus, A.; Pusa, P.; Robicheaux, F.; Sarid, E.; Silveira, D. M.; So, C.; Storey, J. W.; Thompson, R. I.; van der Werf, D. P.; Wurtele, J. S.; Yamazaki, Y.

    2011-01-01

    We demonstrate controllable excitation of the center-of-mass longitudinal motion of a thermal antiproton plasma using a swept-frequency autoresonant drive. When the plasma is cold, dense, and highly collective in nature, we observe that the entire system behaves as a single-particle nonlinear oscillator, as predicted by a recent theory. In contrast, only a fraction of the antiprotons in a warm plasma can be similarly excited. Antihydrogen was produced and trapped by using this technique to drive antiprotons into a positron plasma, thereby initiating atomic recombination.

  2. Plasma placental lactogen in pregnancy.

    Science.gov (United States)

    Raghuramulu, N

    1978-01-01

    Plasma placental lactogen (HPL) and urinary oestrogen levels were investigated in pregnant women belonging to low and high socio-economic groups. Plasma HPL levels increased progressively with increasing gestation in women of both the socio-economic groups. The mean values in the two groups were not statistically different at any period of gestation. No correlation was observed between the birth weight of the infant and the maternal plasma placental lactogen levels at term. A positive correlation was observed between urinary oestrogen excretion and plasma HPL concentration.

  3. Autoresonant Excitation of Antiproton Plasmas

    CERN Document Server

    Andresen, Gorm B; Baquero-Ruiz, Marcelo; Bertsche, William; Bowe, Paul D; Butler, Eoin; Carpenter, P T; Cesar, Claudio L; Chapman, Steven; Charlton, Michael; Fajans, Joel; Friesen, Tim; Fujiwara, Makoto C; Gill, David R; Hangst, Jeffrey S; Hardy, Walter N; Hayden, Michael E; Humphries, Andrew J; Hurt, J L; Hydomako, Richard; Jonsell, Svante; Madsen, Niels; Menary, Scott; Nolan, Paul; Olchanski, Konstantin; Olin, Art; Povilus, Alexander; Pusa, Petteri; Robicheaux, Francis; Sarid, Eli; Silveira, Daniel M; So, Chukman; Storey, James W; Thompson, Robert I; van der Werf, Dirk P; Wurtele, Jonathan S; Yamazaki, Yasunori

    2011-01-01

    We demonstrate controllable excitation of the center-of-mass longitudinal motion of a thermal antiproton plasma using a swept-frequency autoresonant drive. When the plasma is cold, dense, and highly collective in nature, we observe that the entire system behaves as a single-particle nonlinear oscillator, as predicted by a recent theory. In contrast, only a fraction of the antiprotons in a warm plasma can be similarly excited. Antihydrogen was produced and trapped by using this technique to drive antiprotons into a positron plasma, thereby initiating atomic recombination.

  4. The Framework of Plasma Physics

    Science.gov (United States)

    Cowley, Steven

    There have been relatively few good textbooks on plasma physics. Most become simple reference books that might be titled, “Plasma Physics Recipes.” Despite their utility such books do not make good textbooks. For teaching, one needs a book that shows how the basic results and models are part of a coherent whole. Richard Hazeltine and Francois Waelbroeck have written such a textbook: The Framework of Plasma PhysicsAn this book, plasma physics is developed carefully and logically from basic physics principles. The book is not, however, overly formal; physical arguments are used to reduce mathematical complexity.

  5. Plasma cell granuloma of gingiva

    Directory of Open Access Journals (Sweden)

    Balaji Manohar

    2011-01-01

    Full Text Available Plasma cell granuloma is a rare benign lesion characterized by the infiltration of plasma cells; primarily occurring in the lungs. It is also seen to occur in the brain, kidney stomach, heart, and so on. In the intraoral region it is seen to involve the tongue, oral mucosa, and gingiva. This case presents a 42-year-old female, with an enlargement in the maxillary anterior region, treated by excisional biopsy. Histological evaluation revealed plasma cell infiltrates in the connective tissue. The immunohistochemistry revealed kappa and lambda light chains with a polyclonal staining pattern, which confirmed the diagnosis of plasma cell granuloma.

  6. Plasma on a foundry cupola

    Science.gov (United States)

    Pineau, Didier

    An experiment of a plasma torch on a production foundry cupola is reported. The test runs were conducted on a hot blast cupola, the blast temperature in the absence of plasma being 400 C. With the torch, the temperature of the blast was increased to 1000 C. The experiment was conducted for the manufacture of car engines with a 2.5 MW transportable plasma system. The cupola was boosted with a 4 MW torch and results included an increase in production of 45 percent, a decrease in coke rate and no more new iron in the loads. The plasma torch and hot air cupola furnace are described.

  7. Criticality in Plasma Membranes

    Science.gov (United States)

    Machta, Benjamin; Papanikolaou, Stefanos; Sethna, James; Veatch, Sarah

    2011-03-01

    We are motivated by recent observations of micron-sized critical fluctuations in the 2d Ising Universality class in plasma membrane vesicles that are isolated from cortical cytoskeleton. We construct a minimal model of the plasma membrane's interaction with intact cytoskeleton which explains why large scale phase separation has not been observed in Vivo. In addition, we use analytical techniques from conformal field theory and numerical simulations to investigate the form of effective forces mediated by the membrane's proximity to criticality. We show that the range of this force is maximized near a critical point and we quantify its usefulness in mediating communication using techniques from information theory. Finally we use theoretical techniques from statistical physics in conjunction with Monte-Carlo simulations to understand how criticality can be used to increase the efficiency of membrane bound receptor mediated signaling. We expect that this sort of analysis will be broadly useful in understanding and quantifying the role of lipid ``rafts'' in a wide variety of membrane bound processes. Generally, we demonstrate that critical fluctuations provide a physical mechanism to organize and spatially segregate membrane components by providing channels for interaction over relatively large distances.

  8. Measuring Kinetic Plasma Eigenmodes

    Science.gov (United States)

    Mattingly, Sean; Berumen, Jorge; Chu, Feng; Hood, Ryan; Skiff, Fred

    2015-11-01

    We present a method for measuring kinetic plasma eigenmodes of a cylindrical axially magnetized (1 kG) laboratory plasma (n ~109cm-3 , Te ~ 5eV , Ti ~ 0 . 06eV) by measuring velocity space correlation functions. This method simultaneously observes two separate laser induced fluorescence schemes. Each scheme has its own indepedently tunable laser and its own set of collection optics. With this setup, we are able to measure the time - averaged correlation function as a function of position on the cylindrical axis parallel to the magnetic field (z) and velocity on the deconvolved ion velocity distribution function (v) : C (z , v ,z' ,v' , τ) = t. The freedom of two lasers allows us to measure a two dimensional velocity correlation matrix. This matrix is investigated with the Vlasov equation in the collisionless and weakly collisional regime. The former case, which is continuous, is diagonalized with an integral transform defined by P. J. Morrison while the latter case, which is discrete, is diagonalized through the use of Hermite polynomials.

  9. Plasma Redshift Cosmology

    Science.gov (United States)

    Brynjolfsson, Ari

    2011-04-01

    The newly discovered plasma redshift cross section explains a long range of phenomena; including the cosmological redshift, and the intrinsic redshift of Sun, stars, galaxies and quasars. It explains the beautiful black body spectrum of the CMB, and it predicts correctly: a) the observed XRB, b) the magnitude redshift relation for supernovae, and c) the surface- brightness-redshift relation for galaxies. There is no need for Big Bang, Inflation, Dark Energy, Dark Matter, Accelerated Expansion, and Black Holes. The universe is quasi-static and can renew itself forever (for details, see: http://www.plasmaredshift.org). There is no cosmic time dilation. In intergalactic space, the average electron temperature is T = 2.7 million K, and the average electron density is N = 0.0002 per cubic cm. Plasma redshift is derived theoretically from conventional axioms of physics by using more accurate methods than those conventionally used. The main difference is: 1) the proper inclusion of the dielectric constant, 2) more exact calculations of imaginary part of the dielectric constant, and as required 3) a quantum mechanical treatment of the interactions.

  10. Quark gluon plasma

    CERN Document Server

    Nayak, Tapan; Sarkar, Sourav

    2014-01-01

    At extremely high temperatures and densities, protons and neutrons may dissolve into a "soup" of quarks and gluons, called the Quark-Gluon Plasma (QGP). For a few microseconds, shortly after the Big Bang, the Universe was filled with the QGP matter. The search and study of Quark-Gluon Plasma (QGP) is one of the most fundamental research topics of our times. The QGP matter has been probed by colliding heavy ions at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory, New York and the Large Hadron Collider at CERN, Geneva. By colliding heavy-ions at a speed close to that of light, scientists aim to obtain - albeit over a tiny volume of the size of a nucleus and for an infinitesimally short instant - a QGP state. This QGP state can be observed by dedicated experiments, as it reverts to hadronic matter through expansion and cooling. This volume presents some of the current theoretical and experimental understandings in the field of QGP.

  11. Theoretical Plasma Physics

    Energy Technology Data Exchange (ETDEWEB)

    Vahala, George M. [College of William and Mary, Williamsburg, VA (United States)

    2013-12-31

    Lattice Boltzmann algorithms are a mesoscopic method to solve problems in nonlinear physics which are highly parallelized – unlike the direction solution of the original problem. These methods are applied to both fluid and magnetohydrodynamic turbulence. By introducing entropic constraints one can enforce the positive definiteness of the distribution functions and so be able to simulate fluids at high Reynolds numbers without numerical instabilities. By introducing a vector distribution function for the magnetic field one can enforce the divergence free condition on the magnetic field automatically, without the need of divergence cleaning as needed in most direct numerical solutions of the resistive magnetohydrodynamic equations. The principal reason for the high parallelization of lattice Boltzmann codes is that they consist of a kinetic collisional relaxation step (which is purely local) followed by a simple shift of the relaxed data to neighboring lattice sites. In large eddy simulations, the closure schemes are highly nonlocal – the most famous of these schemes is that due to Smagorinsky. Under a lattice Boltzmann representation the Smagorinsky closure is purely local – being simply a particular moment on the perturbed distribution fucntions. After nonlocal fluid moment models were discovered to represent Landau damping, it was found possible to model these fluid models using an appropriate lattice Boltzmann algorithm. The close to ideal parallelization of the lattice Boltzmann codes permitted us to be Gordon Bell finalists on using the Earth Simulation in Japan. We have also been involved in the radio frequency propagation of waves into a tokamak and into a spherical overdense tokamak plasma. Initially we investigated the use of a quasi-optical grill for the launching of lower hybrid waves into a tokamak. It was found that the conducting walls do not prevent the rods from being properly irradiated, the overloading of the quasi-optical grill is not severe

  12. Variation of plasma parameters in a modified mode of plasma production in a double plasma device

    Indian Academy of Sciences (India)

    A Phukan; M K Mishra; B K Saikia; M Chakraborty

    2010-03-01

    A modified mode of plasma production in a double plasma device is presented and plasma parameters are controlled in this configuration. Here plasma is produced by applying a discharge voltage between the hot filaments in the source (cathode) and the target magnetic cage (anode) of the device. In this configuration, the hot electron emitting filaments are present only in the source and the magnetic cage of this is kept at a negative bias such that due to the repulsion of the cage bias, the primary electrons can go to the grounded target and produce plasma there. The plasma parameters can be controlled by varying the voltages applied to the source magnetic cage and the separation grid of the device.

  13. Plasma volume nomograms for use in therapeutic plasma exchange.

    Science.gov (United States)

    Buffaloe, G W; Heineken, F G

    1983-01-01

    Nomograms have been developed for the convenient estimation of the plasma volumes of patients undergoing therapeutic plasma exchange (TPE), based on equations employing height, body weight, and hematocrit. These nomograms are offered as an aid to prescribing continuous-flow TPE procedure exchange volumes.

  14. KINETIC THEORY OF PLASMA WAVES: Part II: Homogeneous Plasma

    NARCIS (Netherlands)

    Westerhof, E.

    2010-01-01

    The theory of electromagnetic waves in a homogeneous plasma is reviewed. The linear response of the plasma to the waves is obtained in the form of the dielectric tensor. Waves ranging from the low frequency Alfven to the high frequency electron cyclotron waves are discussed in the limit of the cold

  15. Kinetic theory of plasma waves: Part II homogeneous plasma

    NARCIS (Netherlands)

    Westerhof, E.

    2000-01-01

    The theory of electromagnetic waves in a homogeneous plasma is reviewed. The linear response of the plasma to the waves is obtained in the form of the dielectric tensor. Waves ranging from the low frequency Alfven to the high frequency electron cyclotron waves are discussed in the limit of the cold

  16. Kinetic theory of plasma waves - Part II: Homogeneous plasma

    NARCIS (Netherlands)

    Westerhof, E.

    2008-01-01

    The theory of electromagnetic waves in a homogeneous plasma is reviewed. The linear response of the plasma to the waves is obtained in the form of the dielectric tensor. Waves ranging from the low frequency Alfven to the high frequency electron cyclotron waves axe discussed in the limit of the cold

  17. Kinetic theory of plasma waves: Part II homogeneous plasma

    NARCIS (Netherlands)

    Westerhof, E.

    2000-01-01

    The theory of electromagnetic waves in a homogeneous plasma is reviewed. The linear response of the plasma to the waves is obtained in the form of the dielectric tensor. Waves ranging from the low frequency Alfven to the high frequency electron cyclotron waves are discussed in the limit of the cold

  18. KINETIC THEORY OF PLASMA WAVES: Part II: Homogeneous Plasma

    NARCIS (Netherlands)

    Westerhof, E.

    2010-01-01

    The theory of electromagnetic waves in a homogeneous plasma is reviewed. The linear response of the plasma to the waves is obtained in the form of the dielectric tensor. Waves ranging from the low frequency Alfven to the high frequency electron cyclotron waves are discussed in the limit of the cold

  19. Kinetic theory of plasma waves - Part II: Homogeneous plasma

    NARCIS (Netherlands)

    Westerhof, E.

    2008-01-01

    The theory of electromagnetic waves in a homogeneous plasma is reviewed. The linear response of the plasma to the waves is obtained in the form of the dielectric tensor. Waves ranging from the low frequency Alfven to the high frequency electron cyclotron waves axe discussed in the limit of the cold

  20. Plasma probe characteristics in low density hydrogen pulsed plasmas

    CERN Document Server

    Astakhov, D I; Lee, C J; Ivanov, V V; Krivtsun, V M; Zotovich, A I; Zyryanov, S M; Lopaev, D V; Bijkerk, F

    2014-01-01

    Probe theories are only applicable in the regime where the probe's perturbation of the plasma can be neglected. However, it is not always possible to know, a priori, that a particular probe theory can be successfully applied, especially in low density plasmas. This is especially difficult in the case of transient, low density plasmas. Here, we applied probe diagnostics in combination with a 2D particle-in-cell model, to an experiment with a pulsed low density hydrogen plasma. The calculations took into account the full chamber geometry, including the plasma probe as an electrode in the chamber. It was found that the simulations reproduce the time evolution of the probe IV characteristics with good accuracy. The disagreement between the simulated and probe measured plasma density is attributed to the limited applicability of probe theory to measurements of low density pulsed plasmas. Indeed, in the case studied here, probe measurements would lead to a large overestimate of the plasma density. In contrast, the ...

  1. On the excess energy of nonequilibrium plasma

    Energy Technology Data Exchange (ETDEWEB)

    Timofeev, A. V. [National Research Centre Kurchatov Institute, Institute of Hydrogen Power Engineering and Plasma Technologies (Russian Federation)

    2012-01-15

    The energy that can be released in plasma due to the onset of instability (the excess plasma energy) is estimated. Three potentially unstable plasma states are considered, namely, plasma with an anisotropic Maxwellian velocity distribution of plasma particles, plasma with a two-beam velocity distribution, and an inhomogeneous plasma in a magnetic field with a local Maxwellian velocity distribution. The excess energy can serve as a measure of the degree to which plasma is nonequilibrium. In particular, this quantity can be used to compare plasmas in different nonequilibrium states.

  2. Plasma treatment of crane rails

    Directory of Open Access Journals (Sweden)

    Владислав Олександрович Мазур

    2016-07-01

    Full Text Available Crane operation results in wear and tear of rails and crane wheels. Renovation and efficiency of these details is therefore relevant. Modern technologies of wheels and rails restoration use surfacing or high-frequency currents treatment. Surface treatment with highly concentrated streams of energy- with a laser beam, plasma jet- is a promising direction.. It is proposed to increase the efficiency of crane rails by means of surface plasma treatment. The modes of treatment have been chosen.. Modelling of plasma jet thermal impact on a solid body of complex shape has been made. Plasma hardening regimes that meet the requirements of production have been defined. Structural transformation of the material in the crane rails on plasma treatment has been investigated. It has been concluded that for carbon and low alloy crane steels the plasma exposure zone is characterized by a high degree of hardened structure dispersion and higher hardness as compared to the hardness after high-frequency quenching. As this takes place phase transformations are both shift (in the upper zone of plasma influence and fluctuation (in the lower zone of the plasma. With high-speed plasma heating granular or lamellar pearlite mainly transforms into austenite. The level of service characteristics of hardened steel, which is achieved in this case is determined by the kinetics and completeness of pearlite → austenite transformation. For carbon and low alloy rail steels plasma hardening can replace bulk hardening, hardening by high-frequency currents, or surfacing. The modes for plasma treatment which make it possible to obtain a surface layer with a certain service characteristics have been defined

  3. High-beta plasma blobs in the morningside plasma sheet

    Directory of Open Access Journals (Sweden)

    G. Haerendel

    Full Text Available Equator-S frequently encountered, i.e. on 30% of the orbits between 1 March and 17 April 1998, strong variations of the magnetic field strength of typically 5–15-min duration outside about 9RE during the late-night/early-morning hours. Very high-plasma beta values were found, varying between 1 and 10 or more. Close conjunctions between Equator-S and Geotail revealed the spatial structure of these "plasma blobs" and their lifetime. They are typically 5–10° wide in longitude and have an antisymmetric plasma or magnetic pressure distribution with respect to the equator, while being altogether low-latitude phenomena 
    (≤ 15°. They drift slowly sunward, exchange plasma across the equator and have a lifetime of at least 15–30 min. While their spatial structure may be due to some sort of mirror instability, little is known about the origin of the high-beta plasma. It is speculated that the morningside boundary layer somewhat further tailward may be the source of this plasma. This would be consistent with the preference of the plasma blobs to occur during quiet conditions, although they are also found during substorm periods. The relation to auroral phenomena in the morningside oval is uncertain. The energy deposition may be mostly too weak to generate a visible signature. However, patchy aurora remains a candidate for more disturbed periods.

    Key words. Magnetospheric physics (plasma convection; plasma sheet; plasma waves and instabilities

  4. MHD control in burning plasmas MHD control in burning plasmas

    Science.gov (United States)

    Donné, Tony; Liang, Yunfeng

    2012-07-01

    Fusion physics focuses on the complex behaviour of hot plasmas confined by magnetic fields with the ultimate aim to develop a fusion power plant. In the future generation of tokamaks like ITER, the power generated by the fusion reactions substantially exceeds the external input power (Pfusion}/Pin >= 10). When this occurs one speaks of a burning plasma. Twenty per cent of the generated fusion power in a burning plasma is carried by the charged alpha particles, which transfer their energy to the ambient plasma in collisions, a process called thermalization. A new phenomenon in burning plasmas is that the alpha particles, which form a minority but carry a large fraction of the plasma kinetic energy, can collectively drive certain types of magneto-hydrodynamic (MHD) modes, while they can suppress other MHD modes. Both types of MHD modes can have desirable effects on the plasma, as well as be detrimental to the plasma. For example, the so-called sawtooth instability, on the one hand, is largely responsible for the transport of the thermalized alpha particles out of the core, but, on the other hand, may result in the loss of the energetic alphas before they have fully thermalized. A further undesirable effect of the sawtooth instability is that it may trigger other MHD modes such as neoclassical tearing modes (NTMs). These NTMs, in turn, are detrimental to the plasma confinement and in some cases may even lead to disruptive termination of the plasma. At the edge of the plasma, finally, so-called edge localized modes or ELMs occur, which result in extremely high transient heat and particle loads on the plasma-facing components of a reactor. In order to balance the desired and detrimental effects of these modes, active feedback control is required. An additional complication occurs in a burning plasma as the external heating power, which is nowadays generally used for plasma control, is small compared to the heating power of the alpha particles. The scientific challenge

  5. Research in plasma physics

    Science.gov (United States)

    1973-01-01

    Three aspects of barium ion cloud dynamics are discussed. First, the effect of the ratio of ion cloud conductivity to background ionospheric conductivity on the motion of barium ion clouds is investigated and compared with observations of barium ion clouds. This study led to the suggestion that the conjugate ionosphere participates in the dynamics of barium ion clouds. Second, analytic work on the deformation of ion clouds is presented. Third, a linearized stability theory was extended to include the effect of the finite extent of an ion cloud, as well as the effect of the ratio of ion cloud to ionospheric conductivities. The stability properties of a plasma with contra-streaming ion beams parallel to a magnetic field are investigated. The results are interpreted in terms of parameters appropriate for collisionless shock waves. It is found that this particular instability can be operative only if the up-stream Alfven Mach number exceeds 5.5.

  6. COSMIC PLASMA DYNAMO

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new dynamo model based on the polarization of plasma is presented in this paper.From the Maxwell equations in a moving medium, a magnetization vector can be causedwith Rongon current. The steady solar magnetic field is solved from the equations. Onthe assumption that the meridianal flow is ignored, the distribution of magnetic field isput out. In the model, there is no additional parameter considered. The intensity ofmagnetic field inside the sun ranges from 1-6T. The surface magnetic field around thepole is in the order of 1×10-3T, at low latitude the calculated surface magnetic fieldhas the order of 1×10-2 T. The maximum magnetic field is around 30° in latitude.

  7. Optimization of plasma amplifiers

    Science.gov (United States)

    Sadler, James D.; Trines, Raoul M. Â. G. Â. M.; Tabak, Max; Haberberger, Dan; Froula, Dustin H.; Davies, Andrew S.; Bucht, Sara; Silva, Luís O.; Alves, E. Paulo; Fiúza, Frederico; Ceurvorst, Luke; Ratan, Naren; Kasim, Muhammad F.; Bingham, Robert; Norreys, Peter A.

    2017-05-01

    Plasma amplifiers offer a route to side-step limitations on chirped pulse amplification and generate laser pulses at the power frontier. They compress long pulses by transferring energy to a shorter pulse via the Raman or Brillouin instabilities. We present an extensive kinetic numerical study of the three-dimensional parameter space for the Raman case. Further particle-in-cell simulations find the optimal seed pulse parameters for experimentally relevant constraints. The high-efficiency self-similar behavior is observed only for seeds shorter than the linear Raman growth time. A test case similar to an upcoming experiment at the Laboratory for Laser Energetics is found to maintain good transverse coherence and high-energy efficiency. Effective compression of a 10 kJ , nanosecond-long driver pulse is also demonstrated in a 15-cm-long amplifier.

  8. Turbulent transport in magnetized plasmas

    CERN Document Server

    Horton, Wendell

    2012-01-01

    This book explains how magnetized plasmas self-organize in states of electromagnetic turbulence that transports particles and energy out of the core plasma faster than anticipated by the fusion scientists designing magnetic confinement systems in the 20th century. It describes theory, experiments and simulations in a unified and up-to-date presentation of the issues of achieving nuclear fusion power.

  9. Plasma chemistry and organic synthesis

    Science.gov (United States)

    Tezuka, M.

    1980-01-01

    The characteristic features of chemical reactions using low temperature plasmas are described and differentiated from those seen in other reaction systems. A number of examples of applications of plasma chemistry to synthetic reactions are mentioned. The production of amino acids by discharge reactions in hydrocarbon-ammonia-water systems is discussed, and its implications for the origins of life are mentioned.

  10. Biocompatibility of plasma nanostructured biopolymers

    Energy Technology Data Exchange (ETDEWEB)

    Slepičková Kasálková, N. [Department of Solid State Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Slepička, P., E-mail: petr.slepicka@vscht.cz [Department of Solid State Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Bačáková, L. [Institute of Physiology, Academy of Sciences of the Czech Republic 142 20 Prague (Czech Republic); Sajdl, P. [Department of Power Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Švorčík, V. [Department of Solid State Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic)

    2013-07-15

    Many areas of medicine such as tissue engineering requires not only mastery of modification techniques but also thorough knowledge of the interaction of cells with solid state substrates. Plasma treatment can be used to effective modification, nanostructuring and therefore can significantly change properties of materials. In this work the biocompatibility of the plasma nanostructured biopolymers substrates was studied. Changes in surface chemical structure were studied by X-ray photoelectron spectroscopy (XPS). The morphology pristine and modified samples were determined using atomic force microscopy (AFM). The surface wettability was determined by goniometry from contact angle. Biocompatibility was determined by in vitro tests, the rat vascular smooth muscle cells (VSMCs) were cultivated on the pristine and plasma modified biopolymer substrates. Their adhesion, proliferation, spreading and homogeneous distribution on polymers was monitored. It was found that the plasma treatment leads to rapid decrease of contact angle for all samples. Contact angle decreased with increasing time of modification. XPS measurements showed that plasma treatment leads to changes in ratio of polar and non-polar groups. Plasma modification was accompanied by a change of surface morphology. Biological tests found that plasma treatment have positive effect on cells adhesion and proliferation cells and affects the size of cell’s adhesion area. Changes in plasma power or in exposure time influences the number of adhered and proliferated cells and their distribution on biopolymer surface.

  11. Waves and instabilities in plasmas

    CERN Document Server

    Chen Liu

    1987-01-01

    The topics covered in these notes are selective and tend to emphasize more on kinetic-theory approaches to waves and instabilities in both uniform and non-uniform plasmas, students are assumed to have some basic knowledge of plasma dynamics in terms of single-particle and fluid descriptions.

  12. Continuous supersonic plasma wind tunnel

    DEFF Research Database (Denmark)

    Andersen, S.A.; Jensen, Vagn Orla; Nielsen, P.

    1968-01-01

    The B field configuration of a Q-device has been modified into a magnetic Laval nozzle. Continuous supersonic plasma flow is observed with M≈3......The B field configuration of a Q-device has been modified into a magnetic Laval nozzle. Continuous supersonic plasma flow is observed with M≈3...

  13. Continuous supersonic plasma wind tunnel

    DEFF Research Database (Denmark)

    Andersen, S.A.; Jensen, Vagn Orla; Nielsen, P.

    1969-01-01

    The normal magnetic field configuration of a Q device has been modified to obtain a 'magnetic Laval nozzle'. Continuous supersonic plasma 'winds' are obtained with Mach numbers ~3. The magnetic nozzle appears well suited for the study of the interaction of supersonic plasma 'winds' with either...

  14. Plasma generation induced by triboelectrification

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Singh, Shailendra Vikram; Michelsen, Poul

    2009-01-01

    A gas discharge plasma can be induced by triboelectrification around a sliding contact. The detailed physical mechanism of triboelectrification is unknown, but an empirical classification scheme can be referred to in practice. It is reported that intense ultra-violet emission from a plasma...

  15. Supersonic induction plasma jet modeling

    Energy Technology Data Exchange (ETDEWEB)

    Selezneva, S.E. E-mail: svetlana2@hermes.usherbS_Selezneva2@hermes.usherb; Boulos, M.I

    2001-06-01

    Numerical simulations have been applied to study the argon plasma flow downstream of the induction plasma torch. It is shown that by means of the convergent-divergent nozzle adjustment and chamber pressure reduction, a supersonic plasma jet can be obtained. We investigate the supersonic and a more traditional subsonic plasma jets impinging onto a normal substrate. Comparing to the subsonic jet, the supersonic one is narrower and much faster. Near-substrate velocity and temperature boundary layers are thinner, so the heat flux near the stagnation point is higher in the supersonic jet. The supersonic plasma jet is characterized by the electron overpopulation and the domination of the recombination over the dissociation, resulting into the heating of the electron gas. Because of these processes, the supersonic induction plasma permits to separate spatially different functions (dissociation and ionization, transport and deposition) and to optimize each of them. The considered configuration can be advantageous in some industrial applications, such as plasma-assisted chemical vapor deposition of diamond and polymer-like films and in plasma spraying of nanoscaled powders.

  16. Plasma-heating by induction

    Science.gov (United States)

    Harrington, K.; Thorpe, M. L.

    1969-01-01

    Induction-heated plasma torch operates with an input of 1 Mw of direct current of which 71 percent is transferred to the plasma and the remainder is consumed by electrical losses in the system. Continuous operation of the torch should be possible for as long as 5,000 hours.

  17. Spectroscopy of Low Temperature Plasma

    CERN Document Server

    Ochkin, Vladimir N

    2009-01-01

    Providing an up-to-date overview on spectroscopical diagnostics of low temperature plasma Spectroscopy of Low Temperature Plasma covers the latest developments and techniques. Written by a distinguished scientist and experienced book author this text is applicable to many fields in materials and surface science as well as nanotechnology and contains numerous appendices with indispensable reference data.

  18. NCSX Plasma Heating Methods

    Energy Technology Data Exchange (ETDEWEB)

    H.W. Kugel; D. Spong; R. Majeski; M. Zarnstorff

    2003-02-28

    The NCSX (National Compact Stellarator Experiment) has been designed to accommodate a variety of heating systems, including ohmic heating, neutral-beam injection, and radio-frequency. Neutral beams will provide one of the primary heating methods for NCSX. In addition to plasma heating, beams are also expected to provide a means for external control over the level of toroidal plasma rotation velocity and its profile. The plan is to provide 3 MW of 50 keV balanced neutral-beam tangential injection with pulse lengths of 500 msec for initial experiments, and to be upgradeable to pulse lengths of 1.5 sec. Subsequent upgrades will add 3 MW of neutral-beam injection. This Chapter discusses the NCSX neutral-beam injection requirements and design issues, and shows how these are provided by the candidate PBX-M (Princeton Beta Experiment-Modification) neutral-beam injection system. In addition, estimations are given for beam-heating efficiencies, scaling of heating efficiency with machine size an d magnetic field level, parameter studies of the optimum beam-injection tangency radius and toroidal injection location, and loss patterns of beam ions on the vacuum chamber wall to assist placement of wall armor and for minimizing the generation of impurities by the energetic beam ions. Finally, subsequent upgrades could add an additional 6 MW of radio-frequency heating by mode-conversion ion-Bernstein wave (MCIBW) heating, and if desired as possible future upgrades, the design also will accommodate high-harmonic fast-wave and electron-cyclotron heating. The initial MCIBW heating technique and the design of the radio-frequency system lend themselves to current drive, so that if current drive became desirable for any reason only minor modifications to the heating system described here would be needed. The radio-frequency system will also be capable of localized ion heating (bulk or tail), and possibly ion-Bernstein-wave-generated sheared flows.

  19. NCSX Plasma Heating Methods

    Energy Technology Data Exchange (ETDEWEB)

    Kugel, H. W.; Spong, D.; Majeski, R.; Zarnstorff, M.

    2008-01-18

    The National Compact Stellarator Experiment (NCSX) has been designed to accommodate a variety of heating systems, including ohmic heating, neutral beam injection, and radio-frequency (rf). Neutral beams will provide one of the primary heating methods for NCSX. In addition to plasma heating, neutral beams are also expected to provide a means for external control over the level of toroidal plasma rotation velocity and its profile. The experimental plan requires 3 MW of 50-keV balanced neutral beam tangential injection with pulse lengths of 500 ms for initial experiments, to be upgradeable to pulse lengths of 1.5 s. Subsequent upgrades will add 3MW of neutral beam injection (NBI). This paper discusses the NCSX NBI requirements and design issues and shows how these are provided by the candidate PBX-M NBI system. In addition, estimations are given for beam heating efficiencies, scaling of heating efficiency with machine size and magnetic field level, parameter studies of the optimum beam injection tangency radius and toroidal injection location, and loss patterns of beam ions on the vacuum chamber wall to assist placement of wall armor and for minimizing the generation of impurities by the energetic beam ions. Finally, subsequent upgrades could add an additional 6 MW of rf heating by mode conversion ion Bernstein wave (MCIBW) heating, and if desired as possible future upgrades, the design also will accommodate high-harmonic fast-wave and electron cyclotron heating. The initial MCIBW heating technique and the design of the rf system lend themselves to current drive, so if current drive became desirable for any reason, only minor modifications to the heating system described here would be needed. The rf system will also be capable of localized ion heating (bulk or tail), and possiblyIBW-generated sheared flows.

  20. Plasma diagnostics and plasma-surface interactions in inductively coupled plasmas

    Science.gov (United States)

    Titus, Monica Joy

    The semiconductor industry's continued trend of manufacturing device features on the nanometer scale requires increased plasma processing control and improved understanding of plasma characteristics and plasma-surface interactions. This dissertation presents a series of experimental results for focus studies conducted in an inductively coupled plasma (ICP) system. First novel "on-wafer" diagnostic tools are characterized and related to plasma characteristics. Second, plasma-polymer interactions are characterized as a function of plasma species and processing parameters. Complementary simulations accompany each focus study to supplement experimental findings. Wafer heating mechanisms in inductively coupled molecular gas plasmas are explored with PlasmaTemp(TM), a novel "on-wafer" diagnostic tool. Experimental wafer measurements are obtained with the PlasmaTemp(TM) wafer processed in argon (Ar) and argon-oxygen (Ar/O2) mixed plasmas. Wafer heating mechanisms were determined by combining the experimental measurements with a 3-dimensional heat transfer model of the wafer. Comparisons between pure Ar and Ar/O2 plasmas demonstrate that two additional wafer heating mechanisms can be important in molecular gas plasmas compared to atomic gas discharges. Thermal heat conduction from the neutral gas and O-atom recombination on wafer surface can contribute as much as 60% to wafer heating under conditions of low-energy ion bombardment in molecular plasmas. Measurements of a second novel "on-wafer" diagnostic sensor, the PlasmaVolt(TM), were tested and validated in the ICP system for Ar plasmas varying in power and pressure. Sensor measurements were interpreted with a numerical sheath simulation and comparison to scaling laws derived from the inhomogeneous sheath model. The study demonstrates sensor measurements are proportional to the RF-current through the sheath and the scaling is a function of sheath impedance. PlasmaVolt(TM) sensor measurements are proportional to the

  1. Intermittent transport in edge plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, O.E.; Naulin, V.; Nielsen, A.H.; Juul Rasmussen, J. [Association EURATOM-Riso National Laboratory, Optics and Plasma Research, Roskilde (Denmark)

    2004-07-01

    The properties of low-frequency convective fluctuations and transport are investigated for the boundary region of magnetized plasmas. We employ a two-dimensional fluid model for the evolution of the global plasma quantities in a geometry and with parameters relevant to the scrape-off layer of confined toroidal plasmas. Strongly intermittent plasma transport is regulated by self-consistently generated sheared poloidal flows and is mediated by burst ejection of particles and heat from the bulk plasma in the form of blobs. Coarse grained probe signals reveal a highly skewed and flat distribution on short time scales, but tends towards a normal distribution at large time scales. Conditionally averaged signals are in perfect agreement with experimental measurements. (authors)

  2. Helicon plasma thruster discharge model

    Energy Technology Data Exchange (ETDEWEB)

    Lafleur, T., E-mail: trevor.lafleur@lpp.polytechnique.fr [Laboratoire de Physique des Plasmas, CNRS, Sorbonne Universités, UPMC Univ Paris 06, Univ Paris-Sud, Ecole Polytechnique, 91128 Palaiseau, France and ONERA - The French Aerospace Lab, 91120 Palaiseau (France)

    2014-04-15

    By considering particle, momentum, and energy balance equations, we develop a semi-empirical quasi one-dimensional analytical discharge model of radio-frequency and helicon plasma thrusters. The model, which includes both the upstream plasma source region as well as the downstream diverging magnetic nozzle region, is compared with experimental measurements and confirms current performance levels. Analysis of the discharge model identifies plasma power losses on the radial and back wall of the thruster as the major performance reduction factors. These losses serve as sinks for the input power which do not contribute to the thrust, and which reduce the maximum plasma density and hence propellant utilization. With significant radial plasma losses eliminated, the discharge model (with argon) predicts specific impulses in excess of 3000 s, propellant utilizations above 90%, and thruster efficiencies of about 30%.

  3. A Multibunch Plasma Wakefield Accelerator

    CERN Document Server

    Kallos, Efthymios; Ben-Zvi, Ilan; Katsouleas, Thomas C; Kimura, Wayne D; Kusche, Karl; Muggli, Patric; Pavlishin, Igor; Pogorelsky, Igor; Yakimenko, Vitaly; Zhou, Feng

    2005-01-01

    We investigate a plasma wakefield acceleration scheme where a train of electron microbunches feeds into a high density plasma. When the microbunch train enters such a plasma that has a corresponding plasma wavelength equal to the microbunch separation distance, a strong wakefield is expected to be resonantly driven to an amplitude that is at least one order of magnitude higher than that using an unbunched beam. PIC simulations have been performed using the beamline parameters of the Brookhaven National Laboratory Accelerator Test Facility operating in the configuration of the STELLA inverse free electron laser (IFEL) experiment. A 65 MeV electron beam is modulated by a 10.6 um CO2 laser beam via an IFEL interaction. This produces a train of ~90 microbunches separated by the laser wavelength. In this paper, we present both a simple theoretical treatment and simulation results that demonstrate promising results for the multibunch technique as a plasma-based accelerator.

  4. Plasma treatment advantages for textiles

    CERN Document Server

    Sparavigna, Amelia

    2008-01-01

    The textile industry is searching for innovative production techniques to improve the product quality, as well as society requires new finishing techniques working in environmental respect. Plasma surface treatments show distinct advantages, because they are able to modify the surface properties of inert materials, sometimes with environment friendly devices. For fabrics, cold plasma treatments require the development of reliable and large systems. Such systems are now existing and the use of plasma physics in industrial problems is rapidly increasing. On textile surfaces, three main effects can be obtained depending on the treatment conditions: the cleaning effect, the increase of microroughness (anti-pilling finishing of wool) and the production of radicals to obtain hydrophilic surfaces. Plasma polymerisation, that is the deposition of solid polymeric materials with desired properties on textile substrates, is under development. The advantage of such plasma treatments is that the modification turns out to ...

  5. High macrosomia rate in healthy fetuses after enlarged nuchal translucency.

    Science.gov (United States)

    Timmerman, E; Pajkrt, E; Snijders, R J M; Bilardo, C M

    2014-02-01

    The aim of this study was to investigate the association of the first trimester screening variables nuchal translucency (NT), pregnancy associated plasma protein (PAPP-A), and free beta-human chorionic gonadotrophin (βhCG) and birth weight, with a focus on the prediction of macrosomia. The database of our Fetal Medicine Unit was searched for all singleton pregnancies, who underwent first trimester Down syndrome screening. Live born infants born at term without chromosomal or structural defects from non-diabetic mothers constituted the study population. Birth weight percentiles were corrected for gestational age at delivery, parity, and gender. Macrosomia was defined as birth weight ≥95th centile. We included 6503 fetuses. Multivariate analysis demonstrated that birth weight centile was positively correlated with NT multiples of the median (MoM), PAPP-A MoM, and maternal body mass index, and it was negatively correlated with smoking. An NT ≥95th centile was present in 315 fetuses (4.8%). Although median birth weight centile was not significantly different between cases with NT ≥95th centile and those 95th centile was more common (11% vs 7%) in the presence of NT ≥95th centile. Pregnancy associated plasma protein was elevated (≥95th centile) in 303 cases (7.9%). Median birth weight was higher (P56 vs P51, P = 0.03) in case of elevated PAPP-A compared with PAPP-A macrosomia rate in case of PAPP-A ≥95th centile (7.4% vs 6.3%, P = 0.07). Area under the receiver operating characteristics (ROC) curve for the prediction of macrosomia (birth weight ≥95th centile) by NT MoM, PAPP-A MoM, maternal body mass index, and maternal smoking was 0.64 (P macrosomia. © 2013 John Wiley & Sons, Ltd.

  6. PLAC4 and beta-HCG mRNA levels are not altered in the maternal circulation of pregnancies with trisomy 21.

    Science.gov (United States)

    Banzola, Irina; Rusterholz, Corinne; Zannoni, Letizia; Rizzo, Nicola; Zhong, Xiao Yan; Caramelli, Elisabetta; Holzgreve, Wolfgang; Farina, Antonio; Hahn, Sinuhe

    2008-12-01

    Beta-human chorionic gonadotropin (HCG) and pregnancy-associated plasma protein (PAPP-A) are placentally produced proteins whose levels are altered in pregnancies with trisomy 21. PLAC4 is located on chromosome 21 and its expression is restricted to the placenta. Here we investigated whether the levels of beta-HCG-, PAPP-A- and PLAC4 mRNA could be able to discriminate pregnancies whose fetus is affected by trisomy 21. Hundred and forty-three blood samples from normal pregnancies and eight samples from trisomic pregnancies were collected. Total RNA was extracted from whole maternal blood, reverse-transcribed and the three mRNAs were quantified by real-time quantitative PCR. Hundred and nine controls were also tested for the serum levels of PAPP-A and HCG proteins. Beta-HCG and PLAC4 mRNAs were detected in all samples, in higher amounts than in plasma, whereas the detection rate for PAPP-A mRNA was below 10%. The levels of beta-HCG mRNA significantly correlated with the circulatory concentrations of the HCG protein. However, neither beta-HCG- nor PLAC4 mRNAs show a significant difference between cases and controls. Maternal blood levels of beta-HCG-, PLAC4- and PAPP-A mRNAs are not useful markers for the screening of pregnancies with trisomy 21 as their concentrations are either not significantly altered (beta-HCG and PLAC4) or too low to be detected (PAPP-A).

  7. Frontomaxillary facial angle in screening for trisomy 21 at 11 + 0 to 13 + 6 weeks.

    Science.gov (United States)

    Borenstein, M; Persico, N; Kagan, K O; Gazzoni, A; Nicolaides, K H

    2008-07-01

    Trisomy 21 is associated with a flat face, which can now be quantified by measurement of the frontomaxillary facial (FMF) angle. The aim of this study was to examine whether in trisomy 21 fetuses fetal nuchal translucency (NT) thickness and maternal serum free ss-human chorionic gonadotropin (ss-hCG) and pregnancy-associated plasma protein-A (PAPP-A) are independent of the FMF angle, and to estimate the performance of a first-trimester screening test for trisomy 21 that includes measurement of the FMF angle. This was a prospective study in singleton pregnancies at 11 + 0 to 13 + 6 weeks of gestation in which three-dimensional volumes of the fetal head were obtained and measurement of the FMF angle performed immediately before fetal karyotyping by chorionic villus sampling (CVS). The women chose to have CVS after risk assessment by a combination of maternal age, fetal NT thickness and maternal serum free ss-hCG and PAPP-A. Regression analysis was used to examine the significance of the association within the euploid and within the trisomy 21 fetuses between the deviation from the normal median in FMF angle and the deviation in NT, free ss-hCG and PAPP-A. We estimated the detection rate (DR) and false positive rate (FPR) of first-trimester screening for trisomy 21 by measuring the FMF angle in all cases and of an alternative policy in which first-stage screening is by fetal NT and maternal serum biochemistry in all patients, followed by second-stage assessment of FMF angle only in those with an intermediate risk (1 in 51 to 1 in 1000) after the first stage. The FMF angle was measured in 782 euploid and 108 trisomy 21 fetuses. In the euploid fetuses the mean FMF angle decreased linearly with CRL from 83.5 degrees at a crown-rump length (CRL) of 45 mm to 76.4 degrees at a CRL of 84 mm. In the euploid fetuses the mean delta FMF angle was 0.0 (SD, 4.264) degrees and the respective values in the trisomy 21 fetuses were 7.172 (SD, 4.092) degrees . Incorporating the FMF

  8. Aerospace applications of pulsed plasmas

    Science.gov (United States)

    Starikovskiy, Andrey

    2012-10-01

    The use of a thermal equilibrium plasma for combustion control dates back more than a hundred years to the advent of internal combustion (IC) engines and spark ignition systems. The same principles are still applied today to achieve high efficiency in various applications. Recently, the potential use of nonequilibrium plasma for ignition and combustion control has garnered increasing interest due to the possibility of plasma-assisted approaches for ignition and flame stabilization. During the past decade, significant progress has been made toward understanding the mechanisms of plasma chemistry interactions, energy redistribution and the nonequilibrium initiation of combustion. In addition, a wide variety of fuels have been examined using various types of discharge plasmas. Plasma application has been shown to provide additional combustion control, which is necessary for ultra-lean flames, high-speed flows, cold low-pressure conditions of high-altitude gas turbine engine (GTE) relight, detonation initiation in pulsed detonation engines (PDE) and distributed ignition control in homogeneous charge-compression ignition (HCCI) engines, among others. The present paper describes the current understanding of the nonequilibrium excitation of combustible mixtures by electrical discharges and plasma-assisted ignition and combustion. Nonequilibrium plasma demonstrates an ability to control ultra-lean, ultra-fast, low-temperature flames and appears to be an extremely promising technology for a wide range of applications, including aviation GTEs, piston engines, ramjets, scramjets and detonation initiation for pulsed detonation engines. To use nonequilibrium plasma for ignition and combustion in real energetic systems, one must understand the mechanisms of plasma-assisted ignition and combustion and be able to numerically simulate the discharge and combustion processes under various conditions.

  9. The 2017 Plasma Roadmap: Low temperature plasma science and technology

    Science.gov (United States)

    Adamovich, I.; Baalrud, S. D.; Bogaerts, A.; Bruggeman, P. J.; Cappelli, M.; Colombo, V.; Czarnetzki, U.; Ebert, U.; Eden, J. G.; Favia, P.; Graves, D. B.; Hamaguchi, S.; Hieftje, G.; Hori, M.; Kaganovich, I. D.; Kortshagen, U.; Kushner, M. J.; Mason, N. J.; Mazouffre, S.; Mededovic Thagard, S.; Metelmann, H.-R.; Mizuno, A.; Moreau, E.; Murphy, A. B.; Niemira, B. A.; Oehrlein, G. S.; Petrovic, Z. Lj; Pitchford, L. C.; Pu, Y.-K.; Rauf, S.; Sakai, O.; Samukawa, S.; Starikovskaia, S.; Tennyson, J.; Terashima, K.; Turner, M. M.; van de Sanden, M. C. M.; Vardelle, A.

    2017-08-01

    Journal of Physics D: Applied Physics published the first Plasma Roadmap in 2012 consisting of the individual perspectives of 16 leading experts in the various sub-fields of low temperature plasma science and technology. The 2017 Plasma Roadmap is the first update of a planned series of periodic updates of the Plasma Roadmap. The continuously growing interdisciplinary nature of the low temperature plasma field and its equally broad range of applications are making it increasingly difficult to identify major challenges that encompass all of the many sub-fields and applications. This intellectual diversity is ultimately a strength of the field. The current state of the art for the 19 sub-fields addressed in this roadmap demonstrates the enviable track record of the low temperature plasma field in the development of plasmas as an enabling technology for a vast range of technologies that underpin our modern society. At the same time, the many important scientific and technological challenges shared in this roadmap show that the path forward is not only scientifically rich but has the potential to make wide and far reaching contributions to many societal challenges.

  10. Meter scale plasma source for plasma wakefield experiments

    Science.gov (United States)

    Vafaei-Najafabadi, N.; Shaw, J. L.; Marsh, K. A.; Joshi, C.; Hogan, M. J.

    2012-12-01

    High accelerating gradients generated by a high density electron beam moving through plasma has been used to double the energy of the SLAC electron beam [1]. During that experiment, the electron current density was high enough to generate its own plasma without significant head erosion. In the newly commissioned FACET facility at SLAC, the peak current will be lower and without pre-ionization, head erosion will be a significant challenge for the planned experiments. In this work we report on our design of a meter scale plasma source for these experiments to effectively avoid the problem of head erosion. The plasma source is based on a homogeneous metal vapor gas column that is generated in a heat pipe oven [2]. A lithium oven over 30 cm long at densities over 1017 cm-3 has been constructed and tested at UCLA. The plasma is then generated by coupling a 10 TW short pulse Ti:Sapphire laser into the gas column using an axicon lens setup. The Bessel profile of the axicon setup creates a region of high intensity that can stretch over the full length of the gas column with approximately constant diameter. In this region of high intensity, the alkali metal vapor is ionized through multi-photon ionization process. In this manner, a fully ionized meter scale plasma of uniform density can be formed. Methods for controlling the plasma diameter and length will also be discussed.

  11. Meter scale plasma source for plasma wakefield experiments

    Energy Technology Data Exchange (ETDEWEB)

    Vafaei-Najafabadi, N.; Shaw, J. L.; Marsh, K. A.; Joshi, C.; Hogan, M. J. [Department of Electrical Engineering, University of California Los Angeles, Los Angeles, CA 90095 (United States); SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States)

    2012-12-21

    High accelerating gradients generated by a high density electron beam moving through plasma has been used to double the energy of the SLAC electron beam [1]. During that experiment, the electron current density was high enough to generate its own plasma without significant head erosion. In the newly commissioned FACET facility at SLAC, the peak current will be lower and without pre-ionization, head erosion will be a significant challenge for the planned experiments. In this work we report on our design of a meter scale plasma source for these experiments to effectively avoid the problem of head erosion. The plasma source is based on a homogeneous metal vapor gas column that is generated in a heat pipe oven [2]. A lithium oven over 30 cm long at densities over 10{sup 17} cm{sup -3} has been constructed and tested at UCLA. The plasma is then generated by coupling a 10 TW short pulse Ti:Sapphire laser into the gas column using an axicon lens setup. The Bessel profile of the axicon setup creates a region of high intensity that can stretch over the full length of the gas column with approximately constant diameter. In this region of high intensity, the alkali metal vapor is ionized through multi-photon ionization process. In this manner, a fully ionized meter scale plasma of uniform density can be formed. Methods for controlling the plasma diameter and length will also be discussed.

  12. Revisiting the plasma sheath - dust in plasma sheath

    CERN Document Server

    Das, G C; Bora, M P

    2015-01-01

    In this work, we have considered the formation of warm plasma sheath in the vicinity of a wall in a plasma with considerable presence of dust particles. As an example, we have used the parameters relevant in case of lunar plasma sheath, though the results obtained in this work could be applied to any other physical situation such as laboratory plasma. In the ion-acoustic time scale, we neglect the dust dynamics. The dust particles affect the sheath dynamics by affecting the Poisson equation which determines the plasma potential in the sheath region. We have assumed the current to a dust particle to be balanced throughout the analysis. This makes the grain potential dependent on plasma potential, which is then incorporated into the Poisson equation. The resultant numerical model becomes an initial value problem, which is described by a 1-D integro-differential equation, which is then solved self-consistently by incorporating the change in plasma potential caused by inclusion of the dust potential in the Poisso...

  13. Arc Plasma Gun With Coaxial Powder Feed

    Science.gov (United States)

    Zaplatynsky, Isidor

    1988-01-01

    Redesigned plasma gun provides improved metallic and ceramic coatings. Particles injected directly through coaxial bore in cathode into central region of plasma jet. Introduced into hotter and faster region of plasma jet.

  14. [Plasma technology for biomedical material applications].

    Science.gov (United States)

    Liu, Z; Li, X

    2000-03-01

    In this paper is introduced the plasma technology for the applications of several species biomaterial such as ophthalmological material, drug delivery system, tissue culture material, blood anticoagulant material as well as plasma surface clearing and plasma sterilization, and so on.

  15. Collisionless Coupling between Explosive Debris Plasma and Magnetized Ambient Plasma

    Science.gov (United States)

    Bondarenko, Anton

    2016-10-01

    The explosive expansion of a dense debris plasma cloud into relatively tenuous, magnetized, ambient plasma characterizes a wide variety of astrophysical and space phenomena, including supernova remnants, interplanetary coronal mass ejections, and ionospheric explosions. In these rarified environments, collective electromagnetic processes rather than Coulomb collisions typically mediate the transfer of momentum and energy from the debris plasma to the ambient plasma. In an effort to better understand the detailed physics of collisionless coupling mechanisms in a reproducible laboratory setting, the present research jointly utilizes the Large Plasma Device (LAPD) and the Phoenix laser facility at UCLA to study the super-Alfvénic, quasi-perpendicular expansion of laser-produced carbon (C) and hydrogen (H) debris plasma through preformed, magnetized helium (He) ambient plasma via a variety of diagnostics, including emission spectroscopy, wavelength-filtered imaging, and magnetic field induction probes. Large Doppler shifts detected in a He II ion spectral line directly indicate initial ambient ion acceleration transverse to both the debris plasma flow and the background magnetic field, indicative of a fundamental process known as Larmor coupling. Characterization of the laser-produced debris plasma via a radiation-hydrodynamics code permits an explicit calculation of the laminar electric field in the framework of a ``hybrid'' model (kinetic ions, charge-neutralizing massless fluid electrons), thus allowing for a simulation of the initial response of a distribution of He II test ions. A synthetic Doppler-shifted spectrum constructed from the simulated velocity distribution of the accelerated test ions excellently reproduces the spectroscopic measurements, confirming the role of Larmor coupling in the debris-ambient interaction.

  16. Experimental investigation of plasma relaxation using a compact coaxial magnetized plasma gun in a background plasma

    Science.gov (United States)

    Zhang, Yue; Lynn, Alan; Gilmore, Mark; Hsu, Scott; University of New Mexico Collaboration; Los Alamos National Laboratory Collaboration

    2013-10-01

    A compact coaxial plasma gun is employed for experimental studies of plasma relaxation in a low density background plasma. Experiments are being conducted in the linear HelCat device at UNM. These studies will advance the knowledge of basic plasma physics in the areas of magnetic relaxation and space and astrophysical plasmas, including the evolution of active galactic jets/radio lobes within the intergalactic medium. The gun is powered by a 120pF ignitron-switched capacitor bank which is operated in a range of 5-10 kV and ~100 kA. Multiple diagnostics are employed to investigate plasma relaxation process. Magnetized Argon plasma bubbles with velocities ~1.2Cs and densities ~1020 m-3 have been achieved. Different distinct regimes of operation with qualitatively different dynamics are identified by fast CCD camera images, with the parameter determining the operation regime. Additionally, a B-dot probe array is employed to measure the spatial toroidal and poloidal magnetic flux evolution to identify detached plasma bubble configurations. Experimental data and analysis will be presented.

  17. Plasma Dark Current in Self-Ionized Plasma Wakefield Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Oz, E.; Deng, S.; Katsouleas, T.; Muggli, P.; /Southern California U.; Iverson, R.; Johnson, D.K.; Krejcik, P.; O' Connell, C.; Siemann, R.H.; Walz, D.; /SLAC; Clayton,; Huang, C.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.B.; Zhou, M.; /UCLA

    2006-01-30

    Evidence of particle trapping has been observed in a beam driven Plasma Wake Field Accelerator (PWFA) experiment, E164X, conducted at the Stanford Linear Accelerator Center by a collaboration which includes USC, UCLA and SLAC. Such trapping produces plasma dark current when the wakefield amplitude is above a threshold value and may place a limit on the maximum acceleration gradient in a PWFA. Trapping and dark current are enhanced when in an ionizing plasma, that is self-ionized by the beam. Here we present experimental results.

  18. Range of fractionated plasma products to optimize plasma resources

    Institute of Scientific and Technical Information of China (English)

    Thierry Burnouf

    2010-01-01

    @@ HUMAN PLASMA is a source material that is crucial for the production of unique therapeutic fractionated products. Indeed, plasma contains hundreds of proteins ensuring many physiological functions. The most abun-dant proteins, albumin and immunoglobulin G (IgG) ,are present at about 35 and 10 g/L,respectively,repre-senting about 80% of all plasma proteins. However,other important therapeutic proteins include the coagu-lation factors (factor Ⅷ (F Ⅷ) ; FIX ; Von Willebrand Factor (VWF), fibrinogen) various protease inhibitors (alpha 1-antitrypsin ; antithrombin; C1-esterase) and anticoagulants (protein C) which exhibit potent physi-ological activity.

  19. Laser Plasmas : Optical guiding of laser beam in nonuniform plasma

    Indian Academy of Sciences (India)

    Tarsem Singh Gill

    2000-11-01

    A plasma channel produced by a short ionising laser pulse is axially nonuniform resulting from the self-defocusing. Through such preformed plasma channel, when a delayed pulse propagates, the phenomena of diffraction, refraction and self-phase modulation come into play. We have solved the nonlinear parabolic partial differential equation governing the propagation characteristics for an approximate analytical solution using variational approach. Results are compared with the theoretical model of Liu and Tripathi (Phys. Plasmas 1, 3100 (1994)) based on paraxial ray approximation. Particular emphasis is on both beam width and longitudinal phase delay which are crucial to many applications.

  20. High macrosomia rate in healthy fetuses after enlarged nuchal translucency

    NARCIS (Netherlands)

    Timmerman, E.; Pajkrt, E.; Snijders, R. J. M.; Bilardo, C. M.

    2014-01-01

    ObjectiveThe aim of this study was to investigate the association of the first trimester screening variables nuchal translucency (NT), pregnancy associated plasma protein (PAPP-A), and free beta-human chorionic gonadotrophin (hCG) and birth weight, with a focus on the prediction of macrosomia. Metho

  1. High macrosomia rate in healthy fetuses after enlarged nuchal translucency

    NARCIS (Netherlands)

    Timmerman, E.; Pajkrt, E.; Snijders, R. J. M.; Bilardo, C. M.

    2014-01-01

    ObjectiveThe aim of this study was to investigate the association of the first trimester screening variables nuchal translucency (NT), pregnancy associated plasma protein (PAPP-A), and free beta-human chorionic gonadotrophin (hCG) and birth weight, with a focus on the prediction of macrosomia. Metho

  2. Negative Plasma Densities Raise Questions

    Energy Technology Data Exchange (ETDEWEB)

    Hazi, A

    2006-01-26

    Nearly all the matter encountered on Earth is either a solid, liquid, or gas. Yet plasma-the fourth state of matter-comprises more than 99 percent of the visible universe. Understanding the physical characteristics of plasmas is important to many areas of scientific research, such as the development of fusion as a clean, renewable energy source. Lawrence Livermore scientists study the physics of plasmas in their pursuit to create fusion energy, because plasmas are an integral part of that process. When deuterium and tritium are heated to the extreme temperatures needed to achieve and sustain a fusion reaction (about 100 million degrees), the electrons in these light atoms become separated from the nuclei. This process of separation is called ionization, and the resulting collection of negatively charged free electrons and positively charged nuclei is known as a plasma. Although plasmas and gases have many similar properties, plasmas differ from gases in that they are good conductors of electricity and can generate magnetic fields. For the past decade, x-ray laser interferometry has been used in the laboratory for measuring a plasma's index of refraction to determine plasma density. (The index of refraction for a given material is defined as the wavelength of light in a vacuum divided by the wavelength of light traveling through the material.) Until now, plasma physicists expected to find an index of refraction less than one. Researchers from Livermore and Colorado State University recently conducted experiments on aluminum plasmas at the Laboratory's COMET laser facility and observed results in which the index of refraction was greater than one. This surprising result implied a negative electron density. Livermore physicist Joseph Nilsen and his colleagues from Livermore and the University of Notre Dame have performed sophisticated calculations to explain this phenomenon. Previously, researchers believed that only free electrons contributed to the index

  3. Labotratory Simulation Experiments of Cometary Plasma

    OpenAIRE

    Minami, S; Baum, P. J.; Kamin, G.; R. S. White; 南, 繁行

    1986-01-01

    Laboratory simulation experiment to study the interaction between a cometary plasma and the solar wind has been performed using the UCR-T 1 space simulation facility at the Institute of Geophysics and Planetary Physics, the University of California, Riverside. Light emitting plasma composed of Sr, Ba and/or C simulating cometary coma plasma is produced by a plasma emitter which interacts with intense plasma flow produced by a co-axial plasma gun simulating the solar wind. The purpose of this ...

  4. Waves in plasmas (part 1 - wave-plasma interaction general background); Ondes dans les plasmas (Partie 1 - interaction onde / plasma: bases physiques)

    Energy Technology Data Exchange (ETDEWEB)

    Dumont, R

    2004-07-01

    This document gathers a series of transparencies presented in the framework of the week-long lectures 'hot plasmas 2004' and dedicated to the physics of wave-plasma interaction. The structure of this document is as follows: 1) wave and diverse plasmas, 2) basic equations (Maxwell equations), 3) waves in a fluid plasma, and 4) waves in a kinetic plasma (collisionless plasma)

  5. Plasma Nanoscience: from Nano-Solids in Plasmas to Nano-Plasmas in Solids

    CERN Document Server

    Ostrikov, K; Meyyappan, M

    2013-01-01

    The unique plasma-specific features and physical phenomena in the organization of nanoscale solid-state systems in a broad range of elemental composition, structure, and dimensionality are critically reviewed. These effects lead to the possibility to localize and control energy and matter at nanoscales and to produce self-organized nano-solids with highly unusual and superior properties. A unifying conceptual framework based on the control of production, transport, and self-organization of precursor species is introduced and a variety of plasma-specific non-equilibrium and kinetics-driven phenomena across the many temporal and spatial scales is explained. When the plasma is localized to micrometer and nanometer dimensions, new emergent phenomena arise. The examples range from semiconducting quantum dots and nanowires, chirality control of single-walled carbon nanotubes, ultra-fine manipulation of graphenes, nano-diamond, and organic matter, to nano-plasma effects and nano-plasmas of different states of matter...

  6. Plasma medicine: an introductory review

    Science.gov (United States)

    Kong, M. G.; Kroesen, G.; Morfill, G.; Nosenko, T.; Shimizu, T.; van Dijk, J.; Zimmermann, J. L.

    2009-11-01

    This introductory review on plasma health care is intended to provide the interested reader with a summary of the current status of this emerging field, its scope, and its broad interdisciplinary approach, ranging from plasma physics, chemistry and technology, to microbiology, biochemistry, biophysics, medicine and hygiene. Apart from the basic plasma processes and the restrictions and requirements set by international health standards, the review focuses on plasma interaction with prokaryotic cells (bacteria), eukaryotic cells (mammalian cells), cell membranes, DNA etc. In so doing, some of the unfamiliar terminology—an unavoidable by-product of interdisciplinary research—is covered and explained. Plasma health care may provide a fast and efficient new path for effective hospital (and other public buildings) hygiene—helping to prevent and contain diseases that are continuously gaining ground as resistance of pathogens to antibiotics grows. The delivery of medically active 'substances' at the molecular or ionic level is another exciting topic of research through effects on cell walls (permeabilization), cell excitation (paracrine action) and the introduction of reactive species into cell cytoplasm. Electric fields, charging of surfaces, current flows etc can also affect tissue in a controlled way. The field is young and hopes are high. It is fitting to cover the beginnings in New Journal of Physics, since it is the physics (and non-equilibrium chemistry) of room temperature atmospheric pressure plasmas that have made this development of plasma health care possible.

  7. Plasma Treatments and Biomass Gasification

    Science.gov (United States)

    Luche, J.; Falcoz, Q.; Bastien, T.; Leninger, J. P.; Arabi, K.; Aubry, O.; Khacef, A.; Cormier, J. M.; Lédé, J.

    2012-02-01

    Exploitation of forest resources for energy production includes various methods of biomass processing. Gasification is one of the ways to recover energy from biomass. Syngas produced from biomass can be used to power internal combustion engines or, after purification, to supply fuel cells. Recent studies have shown the potential to improve conventional biomass processing by coupling a plasma reactor to a pyrolysis cyclone reactor. The role of the plasma is twofold: it acts as a purification stage by reducing production of tars and aerosols, and simultaneously produces a rich hydrogen syngas. In a first part of the paper we present results obtained from plasma treatment of pyrolysis oils. The outlet gas composition is given for various types of oils obtained at different experimental conditions with a pyrolysis reactor. Given the complexity of the mixtures from processing of biomass, we present a study with methanol considered as a model molecule. This experimental method allows a first modeling approach based on a combustion kinetic model suitable to validate the coupling of plasma with conventional biomass process. The second part of the paper is summarizing results obtained through a plasma-pyrolysis reactor arrangement. The goal is to show the feasibility of this plasma-pyrolysis coupling and emphasize more fundamental studies to understand the role of the plasma in the biomass treatment processes.

  8. Thomson scattering from laser plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Moody, J D; Alley, W E; De Groot, J S; Estabrook, K G; Glenzer, S H; Hammer, J H; Jadaud, J P; MacGowan, B J; Rozmus, W; Suter, L J; Williams, E A

    1999-01-12

    Thomson scattering has recently been introduced as a fundamental diagnostic of plasma conditions and basic physical processes in dense, inertial confinement fusion plasmas. Experiments at the Nova laser facility [E. M. Campbell et al., Laser Part. Beams 9, 209 (1991)] have demonstrated accurate temporally and spatially resolved characterization of densities, electron temperatures, and average ionization levels by simultaneously observing Thomson scattered light from ion acoustic and electron plasma (Langmuir) fluctuations. In addition, observations of fast and slow ion acous- tic waves in two-ion species plasmas have also allowed an independent measurement of the ion temperature. These results have motivated the application of Thomson scattering in closed-geometry inertial confinement fusion hohlraums to benchmark integrated radiation-hydrodynamic modeling of fusion plasmas. For this purpose a high energy 4{omega} probe laser was implemented recently allowing ultraviolet Thomson scattering at various locations in high-density gas-filled hohlraum plasmas. In partic- ular, the observation of steep electron temperature gradients indicates that electron thermal transport is inhibited in these gas-filled hohlraums. Hydrodynamic calcula- tions which include an exact treatment of large-scale magnetic fields are in agreement with these findings. Moreover, the Thomson scattering data clearly indicate axial stagnation in these hohlraums by showing a fast rise of the ion temperature. Its timing is in good agreement with calculations indicating that the stagnating plasma will not deteriorate the implosion of the fusion capsules in ignition experiments.

  9. Couette Flow of Unmagnetized Plasma

    CERN Document Server

    Collins, C; Cooper, C M; Flanagan, K; Khalzov, I V; Nornberg, M D; Seidlitz, B; Wallace, J; Forest, C B

    2014-01-01

    Differentially rotating flows of unmagnetized, highly conducting plasmas have been created in the Plasma Couette Experiment. Previously, hot-cathodes have been used to control plasma rotation by a stirring technique [C. Collins et al., Phys. Rev. Lett. 108, 115001(2012)] on the outer cylindrical boundary---these plasmas were nearly rigid rotors, modified only by the presence of a neutral particle drag. Experiments have now been extended to include stirring from an inner boundary, allowing for generalized Couette flow and opening a path for both hydrodynamic and magnetohydrodynamic experiments, as well as fundamental studies of plasma viscosity. Plasma is confined in a cylindrical, axisymmetric, multicusp magnetic field, with $T_e< 10$ eV, $T_i<1$ eV, and $n_e<10^{11}$ cm$^{-3}$. Azimuthal flows (up to 12 km/s, $M=V/c_s\\sim 0.7$) are driven by edge ${\\bf J \\times B}$ torques in helium, neon, argon, and xenon plasmas. We present measurements of a self-consistent, rotation-induced, species-dependent rad...

  10. Special issue on transient plasmas

    Science.gov (United States)

    Bailey, James; Hoarty, David; Mancini, Roberto; Yoneda, Hitoki

    2015-11-01

    This special issue of Journal of Physics B: Atomic, Molecular and Optical Physics is dedicated to the "spectroscopy of transient plasmas" covering plasma conditions produced by a range of pulsed laboratory sources including short and long pulse lasers, pulsed power devices, and free electron lasers (FELs). The full range of plasma spectroscopy up to high energy bremsstrahlung radiation, including line broadening analysis for application to data recorded with the ChemCam instrument on the Mars Science Laboratory rover Curiosity, is covered. This issue is timely as advances in optical lasers and x-ray FELs (XFEL) are enabling transient plasma to be probed at higher energies and shorter durations than ever before. New XFEL facilities being commissioned in Europe and Asia are adding to those operating in the US and Japan and the ELI high power laser project in Europe, due to open this year, will provide short pulse lasers of unprecedented power. This special issue represents a snapshot of the theoretical and experimental research in dense plasmas, electron kinetics, laser-induced breakdown spectroscopy of low temperature plasmas, inertial confinement fusion and non-equilibrium atomic physics using spectroscopy to diagnose plasmas produced by optical lasers, XFELs and pulsed-power machines.

  11. Modeling the Europa plasma torus

    Science.gov (United States)

    Schreier, Ron; Eviatar, Aharon; Vasyliunas, Vytenis M.; Richardson, John D.

    1993-12-01

    The existence of a torus of plasma generated by sputtering from Jupiter's satellite Europa has long been suspected but never yet convincingly demonstrated. Temperature profiles from Voyager plasma observations indicate the presence of hot, possibly freshly picked-up ions in the general vicinity of the orbit of Europa, which may be interpreted as evidence for a local plasma torus. Studies of ion partitioning in the outer regions of the Io torus reveal that the oxygen to sulfur mixing ratio varies with radial distance; this may indicates that oxygen-rich matter is injected from a non-Io source, most probably Europa. We have constructed a quantitative model of a plasma torus near the orbit of Europa which takes into account plasma input from the Io torus, sputtering from the surface of Europa, a great number of ionization and charge exchange processes, and plasma loss by diffusive transport. When the transport time is chosen so that the model's total number density in consistent with the observed total plasma density, the contribution from Europa is found to be significant although not dominant. The model predicts in detail the ion composition, charge states, and the relative fractions of hot Europa-generated and (presumed) cold Io-generated ions. The results are generally consistent with observations from Voyager and can in principle (subject to limitations of data coverage) be confirmed in more detail by Ulysses.

  12. Cold plasma decontamination of foods.

    Science.gov (United States)

    Niemira, Brendan A

    2012-01-01

    Cold plasma is a novel nonthermal food processing technology that uses energetic, reactive gases to inactivate contaminating microbes on meats, poultry, fruits, and vegetables. This flexible sanitizing method uses electricity and a carrier gas, such as air, oxygen, nitrogen, or helium; antimicrobial chemical agents are not required. The primary modes of action are due to UV light and reactive chemical products of the cold plasma ionization process. A wide array of cold plasma systems that operate at atmospheric pressures or in low pressure treatment chambers are under development. Reductions of greater than 5 logs can be obtained for pathogens such as Salmonella, Escherichia coli O157:H7, Listeria monocytogenes, and Staphylococcus aureus. Effective treatment times can range from 120 s to as little as 3 s, depending on the food treated and the processing conditions. Key limitations for cold plasma are the relatively early state of technology development, the variety and complexity of the necessary equipment, and the largely unexplored impacts of cold plasma treatment on the sensory and nutritional qualities of treated foods. Also, the antimicrobial modes of action for various cold plasma systems vary depending on the type of cold plasma generated. Optimization and scale up to commercial treatment levels require a more complete understanding of these chemical processes. Nevertheless, this area of technology shows promise and is the subject of active research to enhance efficacy.

  13. Robustness of virus removal by protein A chromatography is independent of media lifetime.

    Science.gov (United States)

    Lute, Scott; Norling, Lenore; Hanson, Michael; Emery, Rachel; Stinson, Denise; Padua, Kevin; Blank, Greg; Chen, Qi; Brorson, Kurt

    2008-09-26

    The robustness of virus clearance with respect to protein A media reuse was demonstrated using media with four matrix chemistries: Protein A immobilized ProSep A, Poros A50, Protein A ceramic Hyper DF and MabSelect SuRe, an alkali resistant protein A ligand. Endogenous retrovirus clearance, step yield, impurity clearance and other performance parameters were evaluated periodically in media cycled up to 300 times. Media lifetime was generally limited by either declining step yield or media fouling. However, clearance of endogenous retrovirus remained in an acceptable range, either increasing or remaining constant. Multiply cycled media were tested for clearance of three viruses (SV40, X-MuLV, and MMV); clearance was comparable to naïve media. Overall, virus clearance by protein A chromatography appears to be extremely robust with respect to media age.

  14. Birth weight, breast cancer and the potential mediating hormonal environment.

    Science.gov (United States)

    Bukowski, Radek; Chlebowski, Rowan T; Thune, Inger; Furberg, Anne-Sofie; Hankins, Gary D V; Malone, Fergal D; D'Alton, Mary E

    2012-01-01

    Previous studies have shown that woman's risk of breast cancer in later life is associated with her infants birth weights. The objective of this study was to determine if this association is independent of breast cancer risk factors, mother's own birth weight and to evaluate association between infants birth weight and hormonal environment during pregnancy. Independent association would have implications for understanding the mechanism, but also for prediction and prevention of breast cancer. Risk of breast cancer in relation to a first infant's birth weight, mother's own birth weight and breast cancer risk factors were evaluated in a prospective cohort of 410 women in the Framingham Study. Serum concentrations of estriol (E3), anti-estrogen alpha-fetoprotein (AFP), and pregnancy-associated plasma protein-A (PAPP-A) were measured in 23,824 pregnant women from a separate prospective cohort, the FASTER trial. During follow-up (median, 14 years) 31 women (7.6%) were diagnosed with breast cancer. Women with large birth weight infants (in the top quintile) had a higher breast cancer risk compared to other women (hazard ratio (HR), 2.5; 95% confidence interval (CI), 1.2-5.2; P = 0.012). The finding was not affected by adjustment for birth weight of the mother and traditional breast cancer risk factors (adjusted HR, 2.5; 95% CI, 1.2-5.6; P = 0.021). An infant's birth weight had a strong positive relationship with the mother's serum E3/AFP ratio and PAPP-A concentration during pregnancy. Adjustment for breast cancer risk factors did not have a material effect on these relationships. Giving birth to an infant with high birth weight was associated with increased breast cancer risk in later life, independently of mother's own birth weight and breast cancer risk factors and was also associated with a hormonal environment during pregnancy favoring future breast cancer development and progression.

  15. Maternal serum human placental growth hormone at 11 to 13 weeks in trisomy 21 and trisomy 18 pregnancies.

    Science.gov (United States)

    Sifakis, Stavros; Akolekar, Ranjit; Syngelaki, Argyro; De Cruz, Jader; Nicolaides, Kypros H

    2010-03-01

    To investigate the maternal serum concentration of human placental growth hormone (hPGH) in trisomy 21 and trisomy 18 pregnancies at 11 to 13 weeks of gestation and to examine the possible association between fetal nuchal translucency (NT) thickness and maternal serum free beta-human chorionic gonadotrophin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A). The maternal serum concentration of hPGH at 11 to 13 weeks was measured in a case-control study from 28 pregnancies with fetal trisomy 21, 28 with trisomy 18 and 112 pregnancies with euploid fetuses. The median hPGH multiple of the median (MoM) in trisomy 21 and trisomy 18 pregnancies were compared with euploid pregnancies. Serum hPGH was significantly lower in trisomy 21 (0.93 MoM) and trisomy 18 (0.62 MoM) compared to euploid pregnancies (1.02 MoM). There was a significant association between serum hPGH and PAPP-A in both the euploid (r = 0.258, p = 0.006) and trisomy 21 pregnancies (r = 0.410, p = 0.030) but not in trisomy 18 pregnancies (p = 0.445). In the first trimester, serum hPGH in trisomy 21 and trisomy 18 pregnancies is reduced. This is the opposite of findings in previous studies reporting that in the second trimester, trisomy 21 and 18 pregnancies have increased hPGH. Copyright (c) 2010 John Wiley & Sons, Ltd.

  16. Prenatal Screening for Chromosomal Abnormalities in Tabriz, North-West of Iran

    Directory of Open Access Journals (Sweden)

    Zahra Fardyazar

    2013-09-01

    Full Text Available Background: Several studies have indicated that when compared to non-consanguinous marriage, consanguinous marriage may lead to a higher incidence of congenital abnormalities. The study was performed to evaluate few screening tests to estimate the risk of chromosomal abnormalities in the first trimester compared between familial and non-familial marriages. Materials and Methods: In this cross sectional study, 300 pregnant women with singleton pregnancy presenting to Tabriz Al-Zahra hospital from 2007 to 2009 were enrolled as study population. The participants were evaluated about chromosomal malformations using a combination of NT (Nuchal Translucency, PAPP-A (Pregnancy-Associated Plasma Protein A, and free beta- human chorionic gonadotropin (β-hCG. In positive screening test results, the participants underwent fetal karyotyping using amniocentesis or chorionic villi sampling (CVS.Results: Pregnancies with higher risk were observed more among non-consanguineous marriages. The maternal age was not found to be a determinant in this regard. NT and free β-hCG values (but not PAPP-A were significantly different between the two study groups. The triple screening test had a sensitivity of 100%. There were two cases of Down syndrome both belonging to the maternal age less than 35 years and non-consanguineous marriages.Conclusion: Considering that a statistically significant association was not observed between abnormal test results and pregnancy complications (p=0.73, it seems that it is essential to use screening tests in all pregnant women. Especially that the only two pregnancies with Down syndrome in our study were under 35 years of age.

  17. First-trimester combined screening for trisomy 21 in a predominantly Chinese population.

    Science.gov (United States)

    Leung, T Y; Chan, L W; Leung, T N; Fung, T Y; Sahota, D S; Spencer, K; Lau, T K

    2007-01-01

    To examine the effectiveness of first-trimester fetal trisomy 21 screening using a combination of maternal age, nuchal translucency thickness (NT) and maternal serum free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A) levels in a predominantly Chinese population in Hong Kong. This was a prospective study over a 1.5-year period of 2990 women who underwent combined screening for trisomy 21 between 11+0 and 13+6 weeks of gestation in a university fetal medicine unit. NT was measured according to the criteria set by The Fetal Medicine Foundation (FMF), maternal serum free beta-hCG and PAPP-A levels were measured, and the risk of trisomy 21 was calculated using The FMF's algorithm. Fetal karyotyping was advised when the risk was 1 : 300 or above. All subjects were followed up for pregnancy and fetal outcome. Of the 2990 women who underwent the screening program, 99% were Chinese. There were 57 twin pregnancies, giving a total of 3047 fetuses. Thirty-one percent of the women were 35 years old or above. One hundred and eighty-five (6.1%) fetuses were screen-positive; this included 14 cases of trisomy 21 and 17 cases of other chromosomal abnormalities. The positive predictive value was 16.7%. Among the 2862 screen-negative fetuses, only 18 (0.6%) cases had an unknown fetal outcome. There were no cases in which trisomy 21 was missed and the infant was liveborn. First-trimester combined screening for fetal trisomy 21 is highly effective among Chinese subjects. Copyright (c) 2006 ISUOG.

  18. Effect of deviation of nuchal translucency measurements on the performance of screening for trisomy 21.

    Science.gov (United States)

    Kagan, K O; Wright, D; Etchegaray, A; Zhou, Y; Nicolaides, K H

    2009-06-01

    To examine the effect of deviations in median nuchal translucency thickness (NT) and the spread in measurements on the performance of screening for trisomy 21 by maternal age and fetal NT, and by maternal age, fetal NT and maternal serum biochemistry. We simulated the NT and multiples of the median values for pregnancy-associated plasma protein-A (PAPP-A) and free beta-human chorionic gonadotropin (beta-hCG) for 500 000 euploid and 500 000 trisomy 21 pregnancies at 12 weeks of gestation. Detection rates for trisomy 21 and false-positive rates were calculated without adjustments in NT and by adding or subtracting values ranging from 0.1 to 1.0 mm to each observed measurement. In addition, the effects of variation in the scatter of NT measurements were examined by applying a multiplicative factor ranging from 0.5 to 2 to the SD. The detection rate of trisomy 21 for a fixed false-positive rate of 3% in screening by maternal age and fetal NT was 72%, and in screening by maternal age, fetal NT and serum free beta-hCG and PAPP-A it was 86%. A consistent underestimate or overestimate in the measured NT reduced the detection rate of trisomy 21 for a fixed-false positive rate. At a fixed screen-positive cut-off an underestimate in fetal NT reduced the detection rate whereas an overestimate in NT increased the false-positive rate. A widening in the scatter of measurements had only a small impact on the detection rate but it caused a major increase in the false-positive rate. High performance of screening necessitates appropriate measurement of fetal NT. This paper demonstrates the effect of deviations in the median and SD of NT from the expected on the performance of screening and can form the basis of audit of results of individual sonographers. (c) 2009 ISUOG.

  19. First trimester screening using ultrasound and serum markers in Panamanians : f0 actors associated with adverse pregnancy outcomes

    Directory of Open Access Journals (Sweden)

    Tania T Herrera

    2014-01-01

    Full Text Available Background: There is no published data on the association between serum biochemical and ultrasonographic markers and adverse pregnancy outcomes. Therefore, the aim of this study was to determine the factors associated with perinatal outcomes in singleton pregnancies using ultrasound and maternal serum markers during the first trimester in Panamanians. Materials and Methods: This was a prospective observational study of 468 first trimester singleton pregnancies conducted over a 7-year period. All women attending a prenatal screening clinic during the study period were informed of the study and the option to participate. Two maternal serum markers, free β-human chorionic gonadotropin (β-hCG and pregnancy associated plasma protein-A (PAPP-A, and four fetal ultrasound markers, nuchal translucency thickness, nasal bone, flow across the tricuspid valve, and flow in the ductus venosus (DV, were measured by certified maternal fetal medicine specialists. Adverse outcomes included miscarriage, major structural defects, genetic disorders, and major fetal cardiac defects. Results: A total of 454 (97% pregnancies were unaffected. Median maternal age was 31.5 years (range: 18-50. Maternal age was significantly greater in cases of adverse outcome (P = 0.007. The number of adverse outcomes associated with an absent or hypoplastic nasal bone, tricuspid valve regurgitation, and abnormal flow in the DV were significantly greater relative to unaffected pregnancies (Ps < 0.001. No differences were found in fetal crown-rump length or maternal serum levels of β-hCG or PAPP-A. Conclusion: Abnormal ultrasound markers are associated with adverse outcomes. Women with normal ultrasound and serum markers should be reassured of low risk of adverse pregnancy outcomes.

  20. Screening for adverse pregnancy outcome by ductus venosus Doppler at 11-13+6 weeks of gestation.

    Science.gov (United States)

    Maiz, Nerea; Valencia, Catalina; Emmanuel, Edoho E; Staboulidou, Ismini; Nicolaides, Kypros H

    2008-09-01

    To estimate the independent contribution of abnormal flow in the ductus venosus at 11 to 13+6 weeks of gestation in the prediction of major fetal abnormalities and fetal death. This was a prospective assessment of singleton pregnancies by maternal history, serum free beta-hCG, pregnancy-associated plasma protein A (PAPP-A), fetal nuchal translucency thickness, and ductus venosus Doppler. The patients were subdivided into five groups: normal outcome (n=10,120), miscarriage or fetal death (n=185), abnormal karyotype (n=95), and major cardiac (n=20) or noncardiac defect (n=70). Regression analysis was performed to determine the significance of the contribution to adverse outcome of reversed a-wave in the ductus venosus, maternal characteristics, fetal delta nuchal translucency, maternal serum log PAPP-A multiples of the median, and log free beta-hCG multiples of the median. The prevalence of reversed a-wave was significantly higher in the groups with miscarriage or fetal death (10.8%), abnormal karyotype (62.1%), and fetal cardiac defect (25.0%) than in the normal outcome group (3.7%), but not noncardiac defect (4.3%). An adverse outcome was observed in 2.7% of the fetuses with nuchal translucency at or below the 95th centile (in 2.6% of those with normal a-wave and in 7.0% of those with reversed a-wave) and in 19.3% of the fetuses with nuchal translucency above the 95th centile (in 8.9% of those with normal a-wave and in 70.9% of those with reversed a-wave). Reversed a-wave is associated with increased risk for chromosomal abnormalities, cardiac defects, and fetal death. However, in about 80% of cases with reversed a-wave, the pregnancy outcome is normal.

  1. Paper-based plasma sanitizers

    Science.gov (United States)

    Xie, Jingjin; Chen, Qiang; Suresh, Poornima; Roy, Subrata; White, James F.; Mazzeo, Aaron D.

    2017-05-01

    This work describes disposable plasma generators made from metallized paper. The fabricated plasma generators with layered and patterned sheets of paper provide a simple and flexible format for dielectric barrier discharge to create atmospheric plasma without an applied vacuum. The porosity of paper allows gas to permeate its bulk volume and fuel plasma, while plasma-induced forced convection cools the substrate. When electrically driven with oscillating peak-to-peak potentials of ±1 to ±10 kV, the paper-based devices produced both volume and surface plasmas capable of killing microbes. The plasma sanitizers deactivated greater than 99% of Saccharomyces cerevisiae and greater than 99.9% of Escherichia coli cells with 30 s of noncontact treatment. Characterization of plasma generated from the sanitizers revealed a detectable level of UV-C (1.9 nWṡcm-2ṡnm-1), modest surface temperature (60 °C with 60 s of activation), and a high level of ozone (13 ppm with 60 s of activation). These results deliver insights into the mechanisms and suitability of paper-based substrates for active antimicrobial sanitization with scalable, flexible sheets. In addition, this work shows how paper-based generators are conformable to curved surfaces, appropriate for kirigami-like “stretchy” structures, compatible with user interfaces, and suitable for sanitization of microbes aerosolized onto a surface. In general, these disposable plasma generators represent progress toward biodegradable devices based on flexible renewable materials, which may impact the future design of protective garments, skin-like sensors for robots or prosthetics, and user interfaces in contaminated environments.

  2. The interactions of porcine and ovine, serum and colostral immunoglobulins with staphylococcal Protein A.

    Science.gov (United States)

    Bennell, M A; Watson, D L

    1980-01-01

    The purpose of these studies was to determine the proportion of each immunoglobulin class/subclass in blood and colostrum of the pig and sheep, which would bind to staphylococcal Protein A. The concentrations of porcine IgG, IgM, and IgA were determined for serum and colostral whey from five sows. Similar measurements were made on two fractions produce by elution of the sample through a Protein A-Sepharose column: fraction 1, immunoglobulins which did not bind to Protein A, and fraction 2, immunoglobulins which bound to Protein A. The concentrations of ovine IgG1, IgG2, IgM, and IgA were measured for serum and colostral whey from six ewes, and again similar measurements were made after elution of each ovine sample through Protein A-Sepharose. All classes/subclasses of porcine and ovine serum and colostral immunoglobulins bound to Protein A to some extent. More than 90% of IgG from both porcine colostral whey and serum bound to Protein A. Ovine IgG1 from most ewes possessed a low affinity for Protein A whereas ovine IgG2 generally possessed a high affinity; 100% of the IgG2 in ovine colostral whey samples bound to Protein A. There was remarkable variation between individuals in the binding capacity of porcine IgM and each of the ovine immunoglobulins. For the ovine samples, in particular there were distinct differences between Protein A binding capacity of serum and colostral immunoglobulins of the same class/subclass.

  3. Surface plasma source with saddle antenna radio frequency plasma generator.

    Science.gov (United States)

    Dudnikov, V; Johnson, R P; Murray, S; Pennisi, T; Piller, C; Santana, M; Stockli, M; Welton, R

    2012-02-01

    A prototype RF H(-) surface plasma source (SPS) with saddle (SA) RF antenna is developed which will provide better power efficiency for high pulsed and average current, higher brightness with longer lifetime and higher reliability. Several versions of new plasma generators with small AlN discharge chambers and different antennas and magnetic field configurations were tested in the plasma source test stand. A prototype SA SPS was installed in the Spallation Neutron Source (SNS) ion source test stand with a larger, normal-sized SNS AlN chamber that achieved unanalyzed peak currents of up to 67 mA with an apparent efficiency up to 1.6 mA∕kW. Control experiments with H(-) beam produced by SNS SPS with internal and external antennas were conducted. A new version of the RF triggering plasma gun has been designed. A saddle antenna SPS with water cooling is fabricated for high duty factor testing.

  4. Plasma spheroidization of nickel powders in a plasma reactor

    Indian Academy of Sciences (India)

    G Shanmugavelayutham; V Selvarajan

    2004-10-01

    Thermal spray coatings of surfaces with metal, alloy and ceramic materials for protection against corrosion, erosion and wear is an intense field of research. The technique involves injection of the powder into a plasma flame, melting, acceleration of the powder particles, impact and bonding with the substrate. Feedstock powders of metals, alloys and ceramics for thermal spray applications have to meet several requirements. Particle shape, size and its distribution, powder flow characteristics and density are the important factors to be considered in order to ensure high spray efficiency and better coating properties. For smooth and uniform feeding of powders into plasma jet, the powder particles have to be spherical in shape. High temperatures and steep temperatures present in thermal plasma is exploited to spheroidize particles in the present investigation. Nickel powder particles in the size range from 40–100 m were spheroidized using plasma processing. SEM and optical micrographs showed spherical shape of processed particles.

  5. Collapse of nonlinear electron plasma waves in a plasma layer

    Science.gov (United States)

    Grimalsky, V.; Koshevaya, S.; Rapoport, Yu; Kotsarenko, A.

    2016-10-01

    The excitation of nonlinear electron plasma waves in the plasma layer is investigated theoretically. This excitation is realized by means of initial oscillatory perturbations of the volume electron concentration or by initial oscillatory distributions of the longitudinal electron velocity. The amplitudes of the initial perturbations are small and the manifestation of the volume nonlinearity is absent. When the amplitudes of the initial perturbations exceed some thresholds, the values of the electron concentration near the plasma boundary increase catastrophically. The maxima of the electron concentration reach extremely high magnitudes, and sharp peaks in the electron concentration occur, which are localized both in the longitudinal and transverse directions. This effect is interpreted as wave collapse near the plasma boundary.

  6. Dusty plasma as a unique object of plasma physics

    Science.gov (United States)

    Norman, G. E.; Timofeev, A. V.

    2016-11-01

    The self-consistency and basic openness of dusty plasma, charge fluctuations, high dissipation and other features of dusty plasma system lead to the appearance of a number of unusual and unique properties of dusty plasma. “Anomalous” heating of dusty particles, anisotropy of temperatures and other features, parametric resonance, charge fluctuations and interaction potential are among these unique properties. Study is based on analytical approach and numerical simulation. Mechanisms of “anomalous” heating and energy transfer are proposed. Influence of charge fluctuations on the system properties is discussed. The self-consistent, many-particle, fluctuation and anisotropic interparticle interaction potential is studied for a significant range of gas temperature. These properties are interconnected and necessary for a full description of dusty plasmas physics.

  7. The Absence of Plasma in"Spark Plasma Sintering"

    Energy Technology Data Exchange (ETDEWEB)

    Hulbert, Dustin M.; Anders, Andre; Dudina, Dina V.; Andersson, Joakim; Jiang, Dongtao; Unuvar, Cosan; Anselmi-Tamburini, Umberto; Lavernia, Enrique J.; Mukherjee, Amiya K.

    2008-04-10

    Spark plasma sintering (SPS) is a remarkable method for synthesizing and consolidating a large variety of both novel and traditional materials. The process typically uses moderate uni-axial pressures (<100 MPa) in conjunction with a pulsing on-off DC current during operation. There are a number of mechanisms proposed to account for the enhanced sintering abilities of the SPS process. Of these mechanisms, the one most commonly put forth and the one that draws the most controversy involves the presence of momentary plasma generated between particles. This study employees three separate experimental methods in an attempt to determine the presence or absence of plasma during SPS. The methods employed include: in-situ atomic emission spectroscopy, direct visual observation and ultra-fast in-situ voltage measurements. It was found using these experimental techniques that no plasma is present during the SPS process. This result was confirmed using several different powders across a wide spectrum of SPS conditions.

  8. The Absence of Plasma in"Spark Plasma Sintering"

    Energy Technology Data Exchange (ETDEWEB)

    Hulbert, Dustin M.; Anders, Andre; Dudina, Dina V.; Andersson, Joakim; Jiang, Dongtao; Unuvar, Cosan; Anselmi-Tamburini, Umberto; Lavernia, Enrique J.; Mukherjee, Amiya K.

    2008-04-10

    Spark plasma sintering (SPS) is a remarkable method for synthesizing and consolidating a large variety of both novel and traditional materials. The process typically uses moderate uni-axial pressures (<100 MPa) in conjunction with a pulsing on-off DC current during operation. There are a number of mechanisms proposed to account for the enhanced sintering abilities of the SPS process. Of these mechanisms, the one most commonly put forth and the one that draws the most controversy involves the presence of momentary plasma generated between particles. This study employees three separate experimental methods in an attempt to determine the presence or absence of plasma during SPS. The methods employed include: in-situ atomic emission spectroscopy, direct visual observation and ultra-fast in-situ voltage measurements. It was found using these experimental techniques that no plasma is present during the SPS process. This result was confirmed using several different powders across a wide spectrum of SPS conditions.

  9. Radiometric force in dusty plasmas

    CERN Document Server

    Ignatov, A M

    2000-01-01

    A radiofrequency glow discharge plasma, which is polluted with a certain number of dusty grains, is studied. In addition to various dusty plasma phenomena, several specific colloidal effects should be considered. We focus on radiometric forces, which are caused by inhomogeneous temperature distribution. Aside from thermophoresis, the role of temperature distribution in dusty plasmas is an open question. It is shown that inhomogeneous heating of the grain by ion flows results in a new photophoresis like force, which is specific for dusty discharges. This radiometric force can be observable under conditions of recent microgravity experiments.

  10. Wave turbulence in magnetized plasmas

    Directory of Open Access Journals (Sweden)

    S. Galtier

    2009-02-01

    Full Text Available The paper reviews the recent progress on wave turbulence for magnetized plasmas (MHD, Hall MHD and electron MHD in the incompressible and compressible cases. The emphasis is made on homogeneous and anisotropic turbulence which usually provides the best theoretical framework to investigate space and laboratory plasmas. The solar wind and the coronal heating problems are presented as two examples of application of anisotropic wave turbulence. The most important results of wave turbulence are reported and discussed in the context of natural and simulated magnetized plasmas. Important issues and possible spurious interpretations are also discussed.

  11. Controlled fusion and plasma physics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    This document presents the several speeches that took place during the 22nd European Physical Society conference on Controlled Fusion and Plasma Physics in Bournemouth, UK, between the 2nd and 7th July 1995. The talks deal with new experiments carried out on several tokamaks, particularly Tore Supra, concerning plasma confinement and fusion. Some information on specific fusion devices or tokamak devices is provided, as well as results of experiments concerning plasma instability. Separate abstracts were prepared for all the 31 papers in this volume. (TEC).

  12. Radiation reaction in fusion plasmas.

    Science.gov (United States)

    Hazeltine, R D; Mahajan, S M

    2004-10-01

    The effects of a radiation reaction on thermal electrons in a magnetically confined plasma, with parameters typical of planned burning plasma experiments, are studied. A fully relativistic kinetic equation that includes the radiation reaction is derived. The associated rate of phase-space contraction is computed and the relative importance of the radiation reaction in phase space is estimated. A consideration of the moments of the radiation reaction force show that its effects are typically small in reactor-grade confined plasmas, but not necessarily insignificant.

  13. Atrial natriuretic peptides in plasma

    DEFF Research Database (Denmark)

    Goetze, Jens P; Holst Hansen, Lasse; Terzic, Dijana

    2015-01-01

    Measurement of cardiac natriuretic peptides in plasma has gained a diagnostic role in the assessment of heart failure. Plasma measurement is though hampered by the marked instability of the hormones, which has led to the development of analyses that target N-terminal fragments from the prohormone....... These fragments are stable in plasma and represent surrogate markers of the actual natriuretic hormone. Post-translational processing of the precursors, however, is revealing itself to be a complex event with new information still being reported on proteolysis, covalent modifications, and amino acid...

  14. Plasma volume changes during hypoglycaemia

    DEFF Research Database (Denmark)

    Hilsted, J; Frandsen, Henrik Lund; Christensen, N J

    1991-01-01

    -induced hypoglycaemia with total autonomic blockade (alpha-adrenoceptor blockade combined with beta-adrenoceptor blockade and atropine); and insulin-induced hypoglycaemia without any autonomic blockade. In the experiments without autonomic blockade the peripheral venous hematocrit increased, plasma volume decreased......, intravascular albumin content decreased and the transcapillary escape rate of albumin increased. In both experiments with autonomic blockade the increase in venous haematocrit was abolished, yet plasma volume decreased, intravascular albumin content decreased and the transcapillary escape rate of albumin...... increased in these experiments. Thus, the changes in plasma volume and composition in response to hypoglycaemia are due to the combined actions of adrenaline and of insulin....

  15. Microwave Plasma Synthesis of Nanopowders

    Institute of Scientific and Technical Information of China (English)

    Joseph; Lik; Hang; Chau

    2007-01-01

    1 Results and Discussion Nanopowders were synthesized by using microwave plasma synthesis technique.The microwave plasma was operated in atmospheric pressure at a frequency of 2.45 GHz.The reaction temperature is directly related to the power of the microwave generator that can be controlled by adjusting the actual operating current.Firstly,ionization and dissociation of precursor species will be occurred in the plasma,nucleus can then be formed by the collision of these molecules,followed by the growth...

  16. Collective oscillations in a plasma

    CERN Document Server

    Akhiezer, A I; Polovin, R V; ter Haar, D

    2013-01-01

    International Series of Monographs in Natural Philosophy: Collective Oscillations in a Plasma, Volume 7 presents specific topics within the general field of radio waves propagation. This book contains five chapters that address the theory of linear oscillations in a plasma, the spectra of the eigen oscillations, and the mechanism of high-frequency heating. The opening chapters deal with the self-consistent fields; development of initial perturbation; dispersion permittivity tensor of a plasma in a magnetic field; effect of thermal motion of particles on low-frequency resonances; excitation of

  17. Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

    Science.gov (United States)

    2014-10-01

    Gadri, J. R. Roth , T. C. Montie, K. Kelly-Wintenberg, P. P. Y. Tsai, D. J. Helfritch, P. Feldman, D. M. Sherman, F. Karakaya, Z. Y. Chen, and U. P. S...Edinburgh, Scotland : 39th IEEE International Conference on Plasma Science (ICOPS), 2012). 20. Magesh Thiyagarajan, Xavier Gonzales$, Heather...Anderson# and Megan Norfolk. Non-thermal Plasma Induction of Pre-Programmed Cell Death in Monocytic Leukemia Cells. (Edinburgh, Scotland : 39th IEEE

  18. Space Plasma Physics

    Science.gov (United States)

    Wu, S. T.

    2000-01-01

    Dr. James L. Horwitz and R. Hugh Comfort's studies with the high altitude TIDE data have been progressing well. We concluded a study on the relationship of polar cap ion properties observed by TIDE near apogee with solar wind and IMF conditions. We found that in general H+ did not correlate as well as O+ with solar wind and IMF parameters. O+ density correlated(sub IMF), and Kp. At lower solar wind speeds, O+ density decreased with increasing latitude, but this trend was not observed at higher solar wind speeds. By comparing these results with results from other studies of O+ in different parts of the magnetosphere, we concluded that O+ ions often leave the ionosphere near the foot point of the cusp/cleft region, pass through the high-altitude polar cap lobes, and eventually arrive in the plasma sheet. We found that H+ outflows are a persistent feature of the polar cap and are not as dependent on the geophysical conditions; even classical polar wind models show H+ ions readily escaping owing to their low mass. Minor correlations with solar wind drivers were found; specifically, H+ density correlated best with IMF By, V(sub sw)B(sub IMF), and ESW(sub sw).

  19. Welding arc plasma physics

    Science.gov (United States)

    Cain, Bruce L.

    1990-01-01

    The problems of weld quality control and weld process dependability continue to be relevant issues in modern metal welding technology. These become especially important for NASA missions which may require the assembly or repair of larger orbiting platforms using automatic welding techniques. To extend present welding technologies for such applications, NASA/MSFC's Materials and Processes Lab is developing physical models of the arc welding process with the goal of providing both a basis for improved design of weld control systems, and a better understanding of how arc welding variables influence final weld properties. The physics of the plasma arc discharge is reasonably well established in terms of transport processes occurring in the arc column itself, although recourse to sophisticated numerical treatments is normally required to obtain quantitative results. Unfortunately the rigor of these numerical computations often obscures the physics of the underlying model due to its inherent complexity. In contrast, this work has focused on a relatively simple physical model of the arc discharge to describe the gross features observed in welding arcs. Emphasis was placed of deriving analytic expressions for the voltage along the arc axis as a function of known or measurable arc parameters. The model retains the essential physics for a straight polarity, diffusion dominated free burning arc in argon, with major simplifications of collisionless sheaths and simple energy balances at the electrodes.

  20. Space Plasma Effects

    Directory of Open Access Journals (Sweden)

    Miguel Herraiz

    2009-06-01

    Full Text Available

    This paper summarizes the activities carried out by WP 3.1 of WG 3 of COST 296 action. The Work Package

    deals mostly with medium and large ionospheric structures that impacts on GNSS signals. In the research done

    by this European team, particular attention was given to the ionosphere/space weather monitoring, to the analysis

    of the variability of the ionospheric plasma during quiet and disturbed conditions and to the characterization

    of the behavior of low latitudes ionospheric depletions or bubbles and the spatial and temporal gradients of total electron contet.