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Sample records for experimental pelas favas

  1. Effects of replacing rapeseed meal with fava bean at 2 concentrate crude protein levels on feed intake, nutrient digestion, and milk production in cows fed grass silage-based diets.

    PubMed

    Puhakka, L; Jaakkola, S; Simpura, I; Kokkonen, T; Vanhatalo, A

    2016-10-01

    The objective of this study was to evaluate the production and physiological responses of dairy cows to the substitution of fava bean for rapeseed meal at 2 protein supplementation levels in grass silage-based diets. We used 6 primiparous and 6 multiparous Finnish Ayrshire cows in a cyclic changeover trial with a 2×3 factorial arrangement of treatments. The experimental diets consisted of formic acid-treated timothy-meadow fescue silage and 3 isonitrogenous concentrates containing either rapeseed meal, fava bean, or a 1:1 mixture of rapeseed meal and fava bean at low and high inclusion rates, resulting in concentrate crude protein (CP) levels of 15.4 and 19.0% in dry matter. Silage dry matter intake decreased linearly when rapeseed meal was replaced with fava bean, the negative effect being more distinct at the high CP level than the low (-2.3 vs. -0.9kg/d, respectively). Similarly, milk and milk protein yields decreased linearly with fava bean, the change tending to be greater at the high CP level than the low. Yield of milk fat was lower for fava bean compared with rapeseed meal, the difference showing no interaction with CP level. Especially at the high CP level, milk urea concentration was higher with fava bean compared with rapeseed meal indicating better utilization of protein from the rapeseed meal. The apparent total-tract organic matter digestibility did not differ between treatments at the low CP level, but digestibility was higher for fava bean than for rapeseed meal at the high CP level. Plasma concentrations of essential amino acids, including methionine and lysine, were lower for fava bean than for rapeseed meal. Compared with rapeseed meal, the use of fava bean in dairy cow diets as the sole protein supplement decreased silage intake and milk production in highly digestible formic acid-treated grass silage-based diets. PMID:27522411

  2. Effects of replacing rapeseed meal with fava bean at 2 concentrate crude protein levels on feed intake, nutrient digestion, and milk production in cows fed grass silage-based diets.

    PubMed

    Puhakka, L; Jaakkola, S; Simpura, I; Kokkonen, T; Vanhatalo, A

    2016-10-01

    The objective of this study was to evaluate the production and physiological responses of dairy cows to the substitution of fava bean for rapeseed meal at 2 protein supplementation levels in grass silage-based diets. We used 6 primiparous and 6 multiparous Finnish Ayrshire cows in a cyclic changeover trial with a 2×3 factorial arrangement of treatments. The experimental diets consisted of formic acid-treated timothy-meadow fescue silage and 3 isonitrogenous concentrates containing either rapeseed meal, fava bean, or a 1:1 mixture of rapeseed meal and fava bean at low and high inclusion rates, resulting in concentrate crude protein (CP) levels of 15.4 and 19.0% in dry matter. Silage dry matter intake decreased linearly when rapeseed meal was replaced with fava bean, the negative effect being more distinct at the high CP level than the low (-2.3 vs. -0.9kg/d, respectively). Similarly, milk and milk protein yields decreased linearly with fava bean, the change tending to be greater at the high CP level than the low. Yield of milk fat was lower for fava bean compared with rapeseed meal, the difference showing no interaction with CP level. Especially at the high CP level, milk urea concentration was higher with fava bean compared with rapeseed meal indicating better utilization of protein from the rapeseed meal. The apparent total-tract organic matter digestibility did not differ between treatments at the low CP level, but digestibility was higher for fava bean than for rapeseed meal at the high CP level. Plasma concentrations of essential amino acids, including methionine and lysine, were lower for fava bean than for rapeseed meal. Compared with rapeseed meal, the use of fava bean in dairy cow diets as the sole protein supplement decreased silage intake and milk production in highly digestible formic acid-treated grass silage-based diets.

  3. Chemical analysis and hemolytic activity of the fava bean aglycon divicine.

    PubMed

    McMillan, D C; Schey, K L; Meier, G P; Jollow, D J

    1993-01-01

    Divicine is an unstable aglycon metabolite of the fava bean pyrimidine beta-glucoside vicine. Divicine has long been thought to be a mediator of an acute hemolytic crisis, known as favism, in susceptible individuals who ingest fava beans (Vicia faba). However, a recent report has questioned the chemical identity of the divicine that was used in most of the studies on divicine hemotoxicity. The present study was undertaken to examine the hemolytic potential of synthetic divicine. Divicine was synthesized and its identity and purity were confirmed by HPLC, mass spectrometry, and NMR spectroscopy. The stability and redox behavior of divicine, under physiological conditions, were examined by HPLC and cyclic voltammetry. The data indicate that divicine is readily oxidized under aerobic conditions; however, it was sufficiently stable at pH 7.4 to permit its experimental manipulation. When 51Cr-labeled rat erythrocytes were exposed in vitro to the parent glucoside, vicine (5 mM), and then readministered to rats, no decrease in erythrocyte survival was observed. In contrast, erythrocyte survival was dramatically reduced by in vitro exposure to divicine (1.5 mM). These data demonstrate that divicine is a direct-acting hemolytic agent and thus may be a mediator of the hemolytic crisis induced by fava bean ingestion.

  4. Chemical analysis and hemolytic activity of the fava bean aglycon divicine.

    PubMed

    McMillan, D C; Schey, K L; Meier, G P; Jollow, D J

    1993-01-01

    Divicine is an unstable aglycon metabolite of the fava bean pyrimidine beta-glucoside vicine. Divicine has long been thought to be a mediator of an acute hemolytic crisis, known as favism, in susceptible individuals who ingest fava beans (Vicia faba). However, a recent report has questioned the chemical identity of the divicine that was used in most of the studies on divicine hemotoxicity. The present study was undertaken to examine the hemolytic potential of synthetic divicine. Divicine was synthesized and its identity and purity were confirmed by HPLC, mass spectrometry, and NMR spectroscopy. The stability and redox behavior of divicine, under physiological conditions, were examined by HPLC and cyclic voltammetry. The data indicate that divicine is readily oxidized under aerobic conditions; however, it was sufficiently stable at pH 7.4 to permit its experimental manipulation. When 51Cr-labeled rat erythrocytes were exposed in vitro to the parent glucoside, vicine (5 mM), and then readministered to rats, no decrease in erythrocyte survival was observed. In contrast, erythrocyte survival was dramatically reduced by in vitro exposure to divicine (1.5 mM). These data demonstrate that divicine is a direct-acting hemolytic agent and thus may be a mediator of the hemolytic crisis induced by fava bean ingestion. PMID:8374040

  5. Antioxidant Activity of Phenolic Compounds from Fava Bean Sprouts.

    PubMed

    Okumura, Koharu; Hosoya, Takahiro; Kawarazaki, Kai; Izawa, Norihiko; Kumazawa, Shigenori

    2016-06-01

    Fava beans are eaten all over the world and recently, marketing for their sprouts began in Japan. Fava bean sprouts contain more polyphenols and l-3,4-dihydroxyphenylalanine (l-DOPA) than the bean itself. Our antioxidant screening program has shown that fava bean sprouts also possess a higher antioxidant activity than other commercially available sprouts and mature beans. However, the individual constituents of fava bean sprouts are not entirely known. In the present study, we investigated the phenolic compounds of fava bean sprouts and their antioxidant activity. Air-dried fava bean sprouts were treated with 80% methanol and the extract was partitioned in water with chloroform and ethyl acetate. HPLC analysis had shown that the ethyl acetate-soluble parts contained phenolic compounds, separated by preparative HPLC to yield 5 compounds (1-5). Structural analysis using NMR and MS revealed that the compounds isolated were kaempferol glycosides. All isolated compounds had an α-rhamnose at the C-7 position with different sugars attached at the C-3 position. Compounds 1-5 had β-galactose, β-glucose, α-rhamnose, 6-acetyl-β-galactose and 6-acetyl-β-glucose, respectively, at the C-3 position. The amount of l-DOPA in fava bean sprouts was determined by the quantitative (1) H NMR technique. The l-DOPA content was 550.45 mg ± 11.34 /100 g of the raw sprouts. The antioxidant activities of compounds 2-5 and l-DOPA were evaluated using the 2,2-diphenyl-1-picrylhydrazyl scavenging assay. l-DOPA showed high antioxidant activity, but the isolated kaempferol glycosides showed weak activity. Therefore, it can be suggested that l-DOPA contributed to the antioxidant activity of fava bean sprouts.

  6. Antioxidant Activity of Phenolic Compounds from Fava Bean Sprouts.

    PubMed

    Okumura, Koharu; Hosoya, Takahiro; Kawarazaki, Kai; Izawa, Norihiko; Kumazawa, Shigenori

    2016-06-01

    Fava beans are eaten all over the world and recently, marketing for their sprouts began in Japan. Fava bean sprouts contain more polyphenols and l-3,4-dihydroxyphenylalanine (l-DOPA) than the bean itself. Our antioxidant screening program has shown that fava bean sprouts also possess a higher antioxidant activity than other commercially available sprouts and mature beans. However, the individual constituents of fava bean sprouts are not entirely known. In the present study, we investigated the phenolic compounds of fava bean sprouts and their antioxidant activity. Air-dried fava bean sprouts were treated with 80% methanol and the extract was partitioned in water with chloroform and ethyl acetate. HPLC analysis had shown that the ethyl acetate-soluble parts contained phenolic compounds, separated by preparative HPLC to yield 5 compounds (1-5). Structural analysis using NMR and MS revealed that the compounds isolated were kaempferol glycosides. All isolated compounds had an α-rhamnose at the C-7 position with different sugars attached at the C-3 position. Compounds 1-5 had β-galactose, β-glucose, α-rhamnose, 6-acetyl-β-galactose and 6-acetyl-β-glucose, respectively, at the C-3 position. The amount of l-DOPA in fava bean sprouts was determined by the quantitative (1) H NMR technique. The l-DOPA content was 550.45 mg ± 11.34 /100 g of the raw sprouts. The antioxidant activities of compounds 2-5 and l-DOPA were evaluated using the 2,2-diphenyl-1-picrylhydrazyl scavenging assay. l-DOPA showed high antioxidant activity, but the isolated kaempferol glycosides showed weak activity. Therefore, it can be suggested that l-DOPA contributed to the antioxidant activity of fava bean sprouts. PMID:27155370

  7. Hemagglutination by fava bean extract inhibited by simple sugars.

    PubMed

    Perera, C B; Frumin, A M

    1966-02-18

    Hemagglutination by extract of fava bean was inhibited by 5-percent d-glucose, d-fructose, or maltose, but not by 5-percent d-galactose or lactose. Failure to inhibit seems to reflect the presence of a hydroxyl group at the carbon No. 4 position. Hemagglutination was enhanced by dextran of high molecular weight, but not by dextran of low molecular weight. The finding supports the hypothesis that large molecular size explains the enhancement by gum acacia of hemagglutination by fava bean.

  8. [Favism. Acute hemolysis after intake of fava beans].

    PubMed

    Holm, B; Jensenius, M

    1998-01-30

    Acute haemolysis due to Glucose-6-Phosphate-Dehydrogenase deficiency is a common disorder in American and African Blacks, in Mediterranean people and among Orientals. The erythrocytes in affected individuals have insufficient reducing power against toxic peroxydes and free radicals generated during metabolism. Normally, affected individuals are without signs of disease, but under the influence of oxydants severe intravascular haemolysis may occur. One of the most important oxydants is the fava bean which, when ingested, may cause acute favism, a condition which has a 10% mortality if not treated properly. We describe a 35 year-old man from Iraq who developed serious haemolytic anemia with a fall in haemoglobin to 6.5 g/100 ml three days after ingestion of fava beans. He was treated with intravenous fluids and blood transfusions. He recovered and was discharged from hospital after nine days. This is the first described case of favism in Norway.

  9. [Favism. Acute hemolysis after intake of fava beans].

    PubMed

    Holm, B; Jensenius, M

    1998-01-30

    Acute haemolysis due to Glucose-6-Phosphate-Dehydrogenase deficiency is a common disorder in American and African Blacks, in Mediterranean people and among Orientals. The erythrocytes in affected individuals have insufficient reducing power against toxic peroxydes and free radicals generated during metabolism. Normally, affected individuals are without signs of disease, but under the influence of oxydants severe intravascular haemolysis may occur. One of the most important oxydants is the fava bean which, when ingested, may cause acute favism, a condition which has a 10% mortality if not treated properly. We describe a 35 year-old man from Iraq who developed serious haemolytic anemia with a fall in haemoglobin to 6.5 g/100 ml three days after ingestion of fava beans. He was treated with intravenous fluids and blood transfusions. He recovered and was discharged from hospital after nine days. This is the first described case of favism in Norway. PMID:9499726

  10. Characterization of a Panela cheese with added probiotics and fava bean starch

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twenty Lactobacillus spp. and eight Bifidobacterium spp. were screened for their ability to ferment fava bean starch. B. breve ATCC 15700 and L. rhamnosus GG ATCC 53103 were selected as probiotics for use in fresh style Panela cheese. Two types of fresh cheese (with and without 3% fava bean starch) ...

  11. Serum lipoprotein pattern as modified in G6PD-deficient children during haemolytic anaemia induced by fava bean ingestion.

    PubMed

    Dessì, S; Batetta, B; Spano, O; Pulisci, D; Mulas, M F; Muntoni, S; Armeni, M; Sanna, C; Antonucci, R; Pani, P

    1992-04-01

    In the present study, plasma lipid concentrations were determined at different times after admission in sera from G6PD-deficient children during haemolytic crisis induced by fava bean ingestion. Reductions in total, LDL and HDL cholesterol were found in association with the maximum of bone marrow hyperplasia. A return towards normal values occurred with regression of the disease. No changes in other lipid parameters were observed. These data suggest that alterations of lipoprotein pattern, other than in experimental animals, are also present in humans with non-malignant proliferative processes. These changes appear to be a consequence of the disease, probably due to an increased utilization of cholesterol by proliferating cells.

  12. Barcode High Resolution Melting (Bar-HRM) analysis for detection and quantification of PDO "Fava Santorinis" (Lathyrus clymenum) adulterants.

    PubMed

    Ganopoulos, Ioannis; Madesis, Panagiotis; Darzentas, Nikos; Argiriou, Anagnostis; Tsaftaris, Athanasios

    2012-07-15

    Legumes considered as one of the most important crops worldwide. Due to high price as a PDO product, commercial products of "Fava Santorinis" are often subjected to adulterations from other legume products coming from other Lathyrus or Vicia and Pisum species. Using plant DNA barcoding regions (trnL and rpoC) coupled with High Resolution Melting (Bar-HRM) we have developed a method allowing us to detect and authenticate PDO "Fava Santorinis". Bar-HRM proved to be a very sensitive tool able to genotype Lathyrus and its closed relative species and to detect admixtures, being sensitive enough to as low as 1:100 of non-"Fava Santorinis" in "Fava Santorinis" commercial products. In conclusion, Bar-HRM analysis can be a faster, with higher resolution and cost effectiveness alternative method to authenticate PDO "Fava Santorinis" and to quantitatively detect adulterations in "Fava Santorinis" with other relative commercial "Fava" food products. PMID:25683426

  13. Serum lipoprotein pattern as modified in G6PD-deficient children during haemolytic anaemia induced by fava bean ingestion.

    PubMed

    Dessì, S; Batetta, B; Spano, O; Pulisci, D; Mulas, M F; Muntoni, S; Armeni, M; Sanna, C; Antonucci, R; Pani, P

    1992-04-01

    In the present study, plasma lipid concentrations were determined at different times after admission in sera from G6PD-deficient children during haemolytic crisis induced by fava bean ingestion. Reductions in total, LDL and HDL cholesterol were found in association with the maximum of bone marrow hyperplasia. A return towards normal values occurred with regression of the disease. No changes in other lipid parameters were observed. These data suggest that alterations of lipoprotein pattern, other than in experimental animals, are also present in humans with non-malignant proliferative processes. These changes appear to be a consequence of the disease, probably due to an increased utilization of cholesterol by proliferating cells. PMID:1571275

  14. Glutamate functions in stomatal closure in Arabidopsis and fava bean.

    PubMed

    Yoshida, Riichiro; Mori, Izumi C; Kamizono, Nobuto; Shichiri, Yudai; Shimatani, Tetsuo; Miyata, Fumika; Honda, Kenji; Iwai, Sumio

    2016-01-01

    Guard cells are indispensable for higher plants because they control gas exchange and water balance to maintain photosynthetic activity. The signaling processes that govern their movement are controlled by several factors, such as abscisic acid (ABA), blue light, pathogen-associated molecular patterns (PAMPs), and carbon dioxide. Herein, we demonstrated that the amino acid glutamate (Glu), a well-known mammalian neurotransmitter, functions as a novel signaling molecule in stomatal closure in both Arabidopsis and fava bean (Vicia faba L.). Pharmacological and electrophysiological analyses provided important clues for the participation of Glu-receptors, Ca(2+), and protein phosphorylation during the signaling process. Genetic analyses using Arabidopsis ABA-deficient (aba2-1) and ABA-insensitive (abi1-1 and abi2-1) mutants showed that ABA is not required for Glu signaling. However, loss-of-function of the Arabidopsis gene encoding Slow Anion Channel-Associated 1 (SLAC1) and Calcium-Dependent Protein Kinase 6 (CPK6) impaired the Glu response. Moreover, T-DNA knockout mutations of the Arabidopsis Glu receptor-like gene (GLR), GLR3.5, lost their sensitivity to Glu-dependent stomatal closure. Our results strongly support functional Glu-signaling in stomatal closure and the crucial roles of GLRs in this signaling process.

  15. Glutamate functions in stomatal closure in Arabidopsis and fava bean.

    PubMed

    Yoshida, Riichiro; Mori, Izumi C; Kamizono, Nobuto; Shichiri, Yudai; Shimatani, Tetsuo; Miyata, Fumika; Honda, Kenji; Iwai, Sumio

    2016-01-01

    Guard cells are indispensable for higher plants because they control gas exchange and water balance to maintain photosynthetic activity. The signaling processes that govern their movement are controlled by several factors, such as abscisic acid (ABA), blue light, pathogen-associated molecular patterns (PAMPs), and carbon dioxide. Herein, we demonstrated that the amino acid glutamate (Glu), a well-known mammalian neurotransmitter, functions as a novel signaling molecule in stomatal closure in both Arabidopsis and fava bean (Vicia faba L.). Pharmacological and electrophysiological analyses provided important clues for the participation of Glu-receptors, Ca(2+), and protein phosphorylation during the signaling process. Genetic analyses using Arabidopsis ABA-deficient (aba2-1) and ABA-insensitive (abi1-1 and abi2-1) mutants showed that ABA is not required for Glu signaling. However, loss-of-function of the Arabidopsis gene encoding Slow Anion Channel-Associated 1 (SLAC1) and Calcium-Dependent Protein Kinase 6 (CPK6) impaired the Glu response. Moreover, T-DNA knockout mutations of the Arabidopsis Glu receptor-like gene (GLR), GLR3.5, lost their sensitivity to Glu-dependent stomatal closure. Our results strongly support functional Glu-signaling in stomatal closure and the crucial roles of GLRs in this signaling process. PMID:26586261

  16. Acute haemolytic episodes & fava bean consumption in G6PD deficient Iraqis.

    PubMed

    Yahya, H I; al-Allawi, N A

    1993-12-01

    The relation between fava bean ingestion and the occurrence of a haemolytic episode was studied in 102 glucose-6-phosphate dehydrogenate (G6PD) deficient Iraqi patients. None of the patients (mean age 12.8 yr) had a documented similar illness earlier, although all of them gave history of reported regular fava bean ingestion in the past. Further, none of the three patients who were rechallenged (2-3 months later) by the beans developed any clinical or laboratory evidence of haemolysis. The incidence of the haemolytic episodes was found to peak in April, while the fava bean season extends from February to June. This study thus does not support a causal relation between the bean ingestion and the haemolytic episodes in G6PD deficient Iraqis. Possibly, some other factor such as a viral infection may be involved.

  17. Acute haemolytic episodes & fava bean consumption in G6PD deficient Iraqis.

    PubMed

    Yahya, H I; al-Allawi, N A

    1993-12-01

    The relation between fava bean ingestion and the occurrence of a haemolytic episode was studied in 102 glucose-6-phosphate dehydrogenate (G6PD) deficient Iraqi patients. None of the patients (mean age 12.8 yr) had a documented similar illness earlier, although all of them gave history of reported regular fava bean ingestion in the past. Further, none of the three patients who were rechallenged (2-3 months later) by the beans developed any clinical or laboratory evidence of haemolysis. The incidence of the haemolytic episodes was found to peak in April, while the fava bean season extends from February to June. This study thus does not support a causal relation between the bean ingestion and the haemolytic episodes in G6PD deficient Iraqis. Possibly, some other factor such as a viral infection may be involved. PMID:8132232

  18. An increase in renal dopamine does not stimulate natriuresis after fava bean ingestion123

    PubMed Central

    Garland, Emily M; Cesar, Tericka S; Lonce, Suzanna; Ferguson, Marcus C; Robertson, David

    2013-01-01

    Background: Fava beans (Vicia faba) contain dihydroxyphenylalanine (dopa), and their ingestion may increase dopamine stores. Renal dopamine regulates blood pressure and blood volume via a natriuretic effect. Objective: The objective was to determine the relation between dietary fava beans, plasma and urinary catechols, and urinary sodium excretion in 13 healthy volunteers. Design: Catechol and sodium data were compared by using a longitudinal design in which all participants consumed a fixed-sodium study diet on day 1 and the fixed-sodium diet plus fava beans on day 2. Blood was sampled at 1, 2, 4, and 6 h after a meal, and 3 consecutive 4-h urine samples were collected. Results: Mean (±SD) plasma dopa was significantly greater 1 h after fava bean consumption (11,670 ± 5440 compared with 1705 ± 530 pg/mL; P = 0.001) and remained elevated at 6 h. Plasma dopamine increased nearly 15-fold during this period. Fava bean consumption also increased urinary dopamine excretion to 306 ± 116, 360 ± 235, and 159 ± 111 μg/4-h urine sample compared with 45 ± 21, 54 ± 29, and 44 ± 17 μg in the 3 consecutive 4-h samples after the control diet (P ≤ 0.005). These substantial increases in plasma and urinary dopa and dopamine were unexpectedly associated with decreased urinary sodium. Conclusion: The failure of fava bean consumption to provoke natriuresis may indicate that dopa concentrations in commercially available beans do not raise renal dopamine sufficiently to stimulate sodium excretion, at least when beans are added to a moderate-sodium diet in healthy volunteers. This trial was registered at clinicaltrials.gov as NCT01064739. PMID:23553159

  19. Case of neuroleptic malignant-like syndrome precipitated by abrupt fava bean discontinuance.

    PubMed

    Ladha, Shafeeq S; Walker, Russell; Shill, Holly A

    2005-05-01

    Neuroleptic malignant-like syndrome (NMLS) is well described in the treatment of Parkinson's disease. The syndrome is characterized by fever, rigidity, autonomic instability, elevated creatine phosphokinase levels, and altered level of consciousness, which is usually precipitated by levodopa withdrawal. In recent years, patients have used fava beans to treat Parkinson's symptoms, because the beans contain appreciable amounts of levodopa and have been thought to be a safe adjunctive therapy. We describe a case of NMLS, which was precipitated by the abrupt cessation of fava bean ingestion.

  20. Case of neuroleptic malignant-like syndrome precipitated by abrupt fava bean discontinuance.

    PubMed

    Ladha, Shafeeq S; Walker, Russell; Shill, Holly A

    2005-05-01

    Neuroleptic malignant-like syndrome (NMLS) is well described in the treatment of Parkinson's disease. The syndrome is characterized by fever, rigidity, autonomic instability, elevated creatine phosphokinase levels, and altered level of consciousness, which is usually precipitated by levodopa withdrawal. In recent years, patients have used fava beans to treat Parkinson's symptoms, because the beans contain appreciable amounts of levodopa and have been thought to be a safe adjunctive therapy. We describe a case of NMLS, which was precipitated by the abrupt cessation of fava bean ingestion. PMID:15719433

  1. Characterization of a Panela cheese with added probiotics and fava bean starch.

    PubMed

    Escobar, M C; Van Tassell, M L; Martínez-Bustos, F; Singh, M; Castaño-Tostado, E; Amaya-Llano, S L; Miller, M J

    2012-06-01

    Of 20 Lactobacillus and 8 Bifidobacterium species examined, only Bifidobacterium breve ATCC 15700 was able to ferment starch from fava beans. Bifidobacterium breve ATCC 15700 and Lactobacillus rhamnosus GG ATCC 53103 were selected as probiotics for use in fresh-style Panela cheese. Two types of fresh cheese (with and without 3% fava bean starch) were manufactured with 3 combinations of probiotics: L. rhamnosus GG only, B. breve only, or both L. rhamnosus GG and B. breve. During 4 wk of storage at 4°C, the addition of fava bean starch to the cheese was not found to cause significant differences in the viability of either probiotic strain. However, the microstructure and texture of Panela cheese were altered, resulting in a much softer product. A sensory panel showed that the presence of added fava bean starch in Panela cheese was less desirable to consumers, whereas probiotic supplementation had no effect on perceived taste or appearance. Panela cheese could be a suitable food for inclusion of probiotic bacteria.

  2. Characterization of a Panela cheese with added probiotics and fava bean starch.

    PubMed

    Escobar, M C; Van Tassell, M L; Martínez-Bustos, F; Singh, M; Castaño-Tostado, E; Amaya-Llano, S L; Miller, M J

    2012-06-01

    Of 20 Lactobacillus and 8 Bifidobacterium species examined, only Bifidobacterium breve ATCC 15700 was able to ferment starch from fava beans. Bifidobacterium breve ATCC 15700 and Lactobacillus rhamnosus GG ATCC 53103 were selected as probiotics for use in fresh-style Panela cheese. Two types of fresh cheese (with and without 3% fava bean starch) were manufactured with 3 combinations of probiotics: L. rhamnosus GG only, B. breve only, or both L. rhamnosus GG and B. breve. During 4 wk of storage at 4°C, the addition of fava bean starch to the cheese was not found to cause significant differences in the viability of either probiotic strain. However, the microstructure and texture of Panela cheese were altered, resulting in a much softer product. A sensory panel showed that the presence of added fava bean starch in Panela cheese was less desirable to consumers, whereas probiotic supplementation had no effect on perceived taste or appearance. Panela cheese could be a suitable food for inclusion of probiotic bacteria. PMID:22612915

  3. G6PD deficiency and fava bean consumption do not produce hemolysis in Thailand.

    PubMed

    Kitayaporn, D; Charoenlarp, P; Pattaraarechachai, J; Pholpoti, T

    1991-06-01

    Favism, a hemolytic condition associated with fava bean consumption among the glucose-6-phosphate dehydrogenase (G6PD) deficient persons, is well described in the Middle East and Mediterranean areas. However, it is not well documented among the Thais or other Southeast Asians. It is possible that it does exist but that hemolysis which develops is of very minor degree and thus escapes clinical detection. This cross-sectional study hypothesizes that if the fava bean and G6PD deficiency interact in the Thai population, they should cause a significant difference in hematocrit level. The study was carried out in a community hospital in a malaria endemic area. We found that there was a trivial difference of the hematocrit (approximately 1%) which was too small to warrant any clinical significance after controlling for the extraneous effects of age, sex, use of malaria chemoprophylaxis, falciparum infection, use of analgesics/antipyretics and admission status of the patients (p = 0.668). This may be due to the presence of different G6PD mutants to those found elsewhere or due to different consumption patterns of fava beans among the Thais compared to people in other areas with high prevalence of G6PD deficiency.

  4. G6PD deficiency and fava bean consumption do not produce hemolysis in Thailand.

    PubMed

    Kitayaporn, D; Charoenlarp, P; Pattaraarechachai, J; Pholpoti, T

    1991-06-01

    Favism, a hemolytic condition associated with fava bean consumption among the glucose-6-phosphate dehydrogenase (G6PD) deficient persons, is well described in the Middle East and Mediterranean areas. However, it is not well documented among the Thais or other Southeast Asians. It is possible that it does exist but that hemolysis which develops is of very minor degree and thus escapes clinical detection. This cross-sectional study hypothesizes that if the fava bean and G6PD deficiency interact in the Thai population, they should cause a significant difference in hematocrit level. The study was carried out in a community hospital in a malaria endemic area. We found that there was a trivial difference of the hematocrit (approximately 1%) which was too small to warrant any clinical significance after controlling for the extraneous effects of age, sex, use of malaria chemoprophylaxis, falciparum infection, use of analgesics/antipyretics and admission status of the patients (p = 0.668). This may be due to the presence of different G6PD mutants to those found elsewhere or due to different consumption patterns of fava beans among the Thais compared to people in other areas with high prevalence of G6PD deficiency. PMID:1948276

  5. Formation of an activated N-nitroso compound in nitrite-treated fava beans (Vicia faba).

    PubMed

    Piacek-Llanes, B G; Tannenbaum, S R

    1982-01-01

    Fava beans are prominent in the diet of the Colombian population at high gastric cancer risk. Upon nitrite treatment under simulated gastric conditions, a potent mutagen was formed as detected by a forward mutation assay using Salmonella typhimurium TM677 without microsomal activation. The promutagen was partially purified by preparative t.l.c. and normal phase h.p.l.c. of the acetone-soluble portion of a dried aqueous extract. The nitrosated promutagen fully accounted for the mutagenicity observed with whole fava beans. One gram of fresh fava beans yielded approximately 0.35 nmol of mutagen. Mutagenicity data indicated that this mutagen was more potent than N-methyl-N'-nitro-N-nitrosoguanidine. The characteristics of the mutagen were typical of an activated N-nitroso compound, that is a compound in which the N-nitroso moiety is attached to an activating group, such as a carbonyl group. Irradiation of the mutagen yielded a Griess positive reaction. By reverse-phase h.p.l.c. photohydrolysis, a single peak could be ascribed to the mutagen. Its stability varied as a function of pH, being most unstable under alkaline conditions. Cysteine and phosphate concentration had no effect on its rate of decomposition, thereby strongly suggesting that the mutagen is an N-nitrosourea. The results obtained in this study support the hypothesis of carcinogenesis via the intragastric production of activated N-nitroso compounds. PMID:7151253

  6. Gas chromatographic/mass spectrometric analyses of unknown analytical response in imported Fava beans: 4-chloro-6-methoxyindole.

    PubMed

    Petzinger, G; Barry, T L; Roach, J A; Musser, S M; Sphon, J

    1995-01-01

    A halogenated unidentified analytical response (UAR) was encountered in a number of imported Fava bean samples during the Food and Drug Administration's routine pesticide-monitoring program. Gas chromatographic/mass spectrometric (GC/MS) analyses identified the halogenated component as 4-chloro-6-methoxyindole, a naturally occurring promutagen in Fava beans that has been linked to incidents of gastric cancer. Data from electron impact, positive and negative chemical ionization, collision-induced dissociation, and deuteration studies of this compound are presented, along with GC retention time data.

  7. VizieR Online Data Catalog: Fermi-LAT flaring gamma-ray sources from FAVA (Ackermann+, 2013)

    NASA Astrophysics Data System (ADS)

    Ackermann, M.; Ajello, M.; Albert, A.; Allafort, A.; Antolini, E.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Blandford, R. D.; Bloom, E. D.; Bonamente, E.; Bottacini, E.; Bouvier, A.; Brandt, T. J.; Bregeon, J.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Cavazzuti, E.; Cecchi, C.; Charles, E.; Chekhtman, A.; Cheung, C. C.; Chiang, J.; Chiaro, G.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; Cutini, S.; Dalton, M.; D'Ammando, F.; de Angelis, A.; de Palma, F.; Dermer, C. D.; di Venere, L.; Drell, P. S.; Drlica-Wagner, A.; Favuzzi, C.; Fegan, S. J.; Ferrara, E. C.; Focke, W. B.; Franckowiak, A.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Germani, S.; Giglietto, N.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Grenier, I. A.; Grondin, M.-H.; Grove, J. E.; Guiriec, S.; Hadasch, D.; Hanabata, Y.; Harding, A. K.; Hayashida, M.; Hays, E.; Hewitt, J.; Hill, A. B.; Horan, D.; Hou, X.; Hughes, R. E.; Inoue, Y.; Jackson, M. S.; Jogler, T.; J! Ohannesso, N. G.; Johnson, W. N.; Kamae, T.; Kataoka, J.; Kawano, T.; Knodlseder, J.; Kuss, M.; Lande, J.; Larsson, S.; Latronico, L.; Lemoine-Goumard, M.; Longo, F.; Loparco, F.; Lott, B.; Lovellette, M. N.; Lubrano, P.; Mayer, M.; Mazziotta, M. N.; McEnery, J. E.; Michelson, P. F.; Mitthumsiri, W.; Mizuno, T.; Monte, C.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Nemmen, R.; Nuss, E.; Ohsugi, T.; Okumura, A.; Omodei, N.; Orienti, M.; Orlando, E.; Ormes, J. F.; Paneque, D.; Panetta, J. H.; Perkins, J. S.; Pesce-Rollins, M.; Piron, F.; Pivato, G.; Porter, T. A.; Raino, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Romoli, C.; Roth, M.; Sanchez-Conde, M.; Scargle, J. D.; Schulz, A.; Sgro, C.; Siskind, E. J.; Spandre, G.; Spinelli, P.; Suson, D. J.; Takahashi, H.; Takeuchi, Y.; Thayer, J. G.; Thayer, J. B.; Thompson, D. J.; Tibaldo, L.; Tinivella, M.; Torres, D. F.; Tosti, G.; Troja, E.; Tronconi, V.; Usher, T. L.; Vandenbroucke, J.; Vasileiou, V.; Vianello, G.; Vitale, V.; Winer, B. L.; Wood, K. S.; Wood, M.; Yang, Z.

    2015-01-01

    We applied FAVA (Fermi All-sky Variability Analysis) to the first 47 months of Fermi/LAT observations (2008 August 4 to 2012 July 16 UTC), in weekly time intervals. The total number of weeks is 206. We considered two ranges of gamma-ray energy, E>100MeV and E>800MeV, to increase the sensitivity for spectrally soft and hard flares, respectively. We generate measured and expected count maps with a resolution of 0.25deg2 per pixel. We found LAT counterparts for 192 of the 215 FAVA sources. Most of the associated sources, 177, are AGNs. (2 data files).

  8. Gas chromatographic/mass spectrometric analyses of unknown analytical response in imported Fava beans: 4-chloro-6-methoxyindole.

    PubMed

    Petzinger, G; Barry, T L; Roach, J A; Musser, S M; Sphon, J

    1995-01-01

    A halogenated unidentified analytical response (UAR) was encountered in a number of imported Fava bean samples during the Food and Drug Administration's routine pesticide-monitoring program. Gas chromatographic/mass spectrometric (GC/MS) analyses identified the halogenated component as 4-chloro-6-methoxyindole, a naturally occurring promutagen in Fava beans that has been linked to incidents of gastric cancer. Data from electron impact, positive and negative chemical ionization, collision-induced dissociation, and deuteration studies of this compound are presented, along with GC retention time data. PMID:7756907

  9. Haemoglobin-E in the presence of oxidative substances from fava bean may be protective against Plasmodium falciparum malaria.

    PubMed

    Kitayaporn, D; Nelson, K E; Charoenlarp, P; Pholpothi, T

    1992-01-01

    A case-control study was carried out at a community hospital in eastern Thailand in order to study the association between haemoglobin E and Plasmodium falciparum malaria; 271 P. falciparum cases and 271 controls were enrolled. After adjusting for age, sex, time since last malaria attack, history of mosquito net use, and history of fava bean consumption in the previous month, neither heterozygous nor homozygous haemoglobin E provided significant protection against P. falciparum infection, with odds ratios (OR) = 0.91 (95% confidence limits = 0.61, 1.36) and 0.78 (0.34, 1.82) respectively when compared to persons with haemoglobin A who were not consumers of fava beans. However, haemoglobin E carriers who ate fava beans were significantly protected against P. falciparum malaria with OR = 0.26 (0.09, 0.76) and OR = 0.001 (0.00, 1120.59) for subjects with heterozygous and homozygous haemoglobin E, respectively. The study suggests a possible synergistic protective effect of haemoglobin E on the risk of P. falciparum malaria in subjects who have consumed fava beans.

  10. Haemoglobin-E in the presence of oxidative substances from fava bean may be protective against Plasmodium falciparum malaria.

    PubMed

    Kitayaporn, D; Nelson, K E; Charoenlarp, P; Pholpothi, T

    1992-01-01

    A case-control study was carried out at a community hospital in eastern Thailand in order to study the association between haemoglobin E and Plasmodium falciparum malaria; 271 P. falciparum cases and 271 controls were enrolled. After adjusting for age, sex, time since last malaria attack, history of mosquito net use, and history of fava bean consumption in the previous month, neither heterozygous nor homozygous haemoglobin E provided significant protection against P. falciparum infection, with odds ratios (OR) = 0.91 (95% confidence limits = 0.61, 1.36) and 0.78 (0.34, 1.82) respectively when compared to persons with haemoglobin A who were not consumers of fava beans. However, haemoglobin E carriers who ate fava beans were significantly protected against P. falciparum malaria with OR = 0.26 (0.09, 0.76) and OR = 0.001 (0.00, 1120.59) for subjects with heterozygous and homozygous haemoglobin E, respectively. The study suggests a possible synergistic protective effect of haemoglobin E on the risk of P. falciparum malaria in subjects who have consumed fava beans. PMID:1412643

  11. Simultaneous Determination of Levodopa and Carbidopa from Fava Bean, Green Peas and Green Beans by High Performance Liquid Gas Chromatography

    PubMed Central

    Mehran S.M., Mohseni; B., Golshani

    2013-01-01

    Introduction: According to many studies, sprouted fava beans are a rich source of levo-dihydroxy phenylalanine (L-dopa) the precursor of dopamine, and they are now being investigated for use in the management of Parkinson’s disease. The addition of Carbidopa (C-dopa) can reduce the daily use of the L-dopa dosage requirements and it can also reduce the side effects which are associated with the L-dopa administration. Material and Methods: The present research was conducted to find the levo-dihydroxy phenylalanine (L-dopa) and Carbidopa (C-dopa) in fava beans, green peas and green beans by High Performance Gas Chromatography (HPLC). Carbidopa (C-dopa) is a peripheral decarboxylase inhibitor. As a substitution therapy, it used in combination to treat Parkinson’s disease. Result: We obtained L-dopa and C-dopa from fava beans which were in the fresh and dry sprouted form, whose concentrations were 1.4,1.5 and 2.6,2.4 mg/ml respectively. The maximal stimulation of the L-DOPA content was seen on day 8 for the fava beans, which was 100% higher than that of the control level. Conclusion: The results of this study indicate that faba beans are a good source of natural L-dopa and C-dopa. The quantification of this capacity according to the stage and the plant part could be suitable for applications in the food industry and in plant medicine. The consumption of fava beans can increase the levels of L-dopa and C-dopa in the blood, with a marked improvement in the motor performance of the patients with parkinson disease, without any side effects. PMID:23905090

  12. Gas Chromatography/Mass Spectrometry-Based Metabolomic Profiling Reveals Alterations in Mouse Plasma and Liver in Response to Fava Beans

    PubMed Central

    Zhong, Guobing; Yan, Dongjing; Zeng, Huazong; Cai, Wangwei

    2016-01-01

    Favism is a life-threatening hemolytic anemia resulting from the intake of fava beans by susceptible individuals with low erythrocytic glucose 6-phosphate dehydrogenase (G6PD) activity. However, little is known about the metabolomic changes in plasma and liver after the intake of fava beans in G6PD normal and deficient states. In this study, gas chromatography/mass spectrometry was used to analyze the plasma and liver metabolic alterations underlying the effects of fava beans in C3H- and G6PD-deficient (G6PDx) mice, and to find potential biomarkers and metabolic changes associated with favism. Our results showed that fava beans induced oxidative stress in both C3H and G6PDx mice. Significantly, metabolomic differences were observed in plasma and liver between the control and fava bean treated groups of both C3H and G6PDx mice. The levels of 7 and 21 metabolites in plasma showed significant differences between C3H-control (C3H-C)- and C3H fava beans-treated (C3H-FB) mice, and G6PDx-control (G6PDx-C)- and G6PDx fava beans-treated (G6PDx-FB) mice, respectively. Similarly, the levels of 7 and 25 metabolites in the liver showed significant differences between C3H and C3H-FB, and G6PDx and G6PDx-FB, respectively. The levels of oleic acid, linoleic acid, and creatinine were significantly increased in the plasma of both C3H-FB and G6PDx-FB mice. In the liver, more metabolic alterations were observed in G6PDx-FB mice than in C3H-FB mice, and were involved in a sugar, fatty acids, amino acids, cholesterol biosynthesis, the urea cycle, and the nucleotide metabolic pathway. These findings suggest that oleic acid, linoleic acid, and creatinine may be potential biomarkers of the response to fava beans in C3H and G6PDx mice and therefore that oleic acid and linoleic acid may be involved in oxidative stress induced by fava beans. This study demonstrates that G6PD activity in mice can affect their metabolic pathways in response to fava beans. PMID:26981882

  13. Gas Chromatography/Mass Spectrometry-Based Metabolomic Profiling Reveals Alterations in Mouse Plasma and Liver in Response to Fava Beans.

    PubMed

    Xiao, Man; Du, Guankui; Zhong, Guobing; Yan, Dongjing; Zeng, Huazong; Cai, Wangwei

    2016-01-01

    Favism is a life-threatening hemolytic anemia resulting from the intake of fava beans by susceptible individuals with low erythrocytic glucose 6-phosphate dehydrogenase (G6PD) activity. However, little is known about the metabolomic changes in plasma and liver after the intake of fava beans in G6PD normal and deficient states. In this study, gas chromatography/mass spectrometry was used to analyze the plasma and liver metabolic alterations underlying the effects of fava beans in C3H- and G6PD-deficient (G6PDx) mice, and to find potential biomarkers and metabolic changes associated with favism. Our results showed that fava beans induced oxidative stress in both C3H and G6PDx mice. Significantly, metabolomic differences were observed in plasma and liver between the control and fava bean treated groups of both C3H and G6PDx mice. The levels of 7 and 21 metabolites in plasma showed significant differences between C3H-control (C3H-C)- and C3H fava beans-treated (C3H-FB) mice, and G6PDx-control (G6PDx-C)- and G6PDx fava beans-treated (G6PDx-FB) mice, respectively. Similarly, the levels of 7 and 25 metabolites in the liver showed significant differences between C3H and C3H-FB, and G6PDx and G6PDx-FB, respectively. The levels of oleic acid, linoleic acid, and creatinine were significantly increased in the plasma of both C3H-FB and G6PDx-FB mice. In the liver, more metabolic alterations were observed in G6PDx-FB mice than in C3H-FB mice, and were involved in a sugar, fatty acids, amino acids, cholesterol biosynthesis, the urea cycle, and the nucleotide metabolic pathway. These findings suggest that oleic acid, linoleic acid, and creatinine may be potential biomarkers of the response to fava beans in C3H and G6PDx mice and therefore that oleic acid and linoleic acid may be involved in oxidative stress induced by fava beans. This study demonstrates that G6PD activity in mice can affect their metabolic pathways in response to fava beans. PMID:26981882

  14. Gas Chromatography/Mass Spectrometry-Based Metabolomic Profiling Reveals Alterations in Mouse Plasma and Liver in Response to Fava Beans.

    PubMed

    Xiao, Man; Du, Guankui; Zhong, Guobing; Yan, Dongjing; Zeng, Huazong; Cai, Wangwei

    2016-01-01

    Favism is a life-threatening hemolytic anemia resulting from the intake of fava beans by susceptible individuals with low erythrocytic glucose 6-phosphate dehydrogenase (G6PD) activity. However, little is known about the metabolomic changes in plasma and liver after the intake of fava beans in G6PD normal and deficient states. In this study, gas chromatography/mass spectrometry was used to analyze the plasma and liver metabolic alterations underlying the effects of fava beans in C3H- and G6PD-deficient (G6PDx) mice, and to find potential biomarkers and metabolic changes associated with favism. Our results showed that fava beans induced oxidative stress in both C3H and G6PDx mice. Significantly, metabolomic differences were observed in plasma and liver between the control and fava bean treated groups of both C3H and G6PDx mice. The levels of 7 and 21 metabolites in plasma showed significant differences between C3H-control (C3H-C)- and C3H fava beans-treated (C3H-FB) mice, and G6PDx-control (G6PDx-C)- and G6PDx fava beans-treated (G6PDx-FB) mice, respectively. Similarly, the levels of 7 and 25 metabolites in the liver showed significant differences between C3H and C3H-FB, and G6PDx and G6PDx-FB, respectively. The levels of oleic acid, linoleic acid, and creatinine were significantly increased in the plasma of both C3H-FB and G6PDx-FB mice. In the liver, more metabolic alterations were observed in G6PDx-FB mice than in C3H-FB mice, and were involved in a sugar, fatty acids, amino acids, cholesterol biosynthesis, the urea cycle, and the nucleotide metabolic pathway. These findings suggest that oleic acid, linoleic acid, and creatinine may be potential biomarkers of the response to fava beans in C3H and G6PDx mice and therefore that oleic acid and linoleic acid may be involved in oxidative stress induced by fava beans. This study demonstrates that G6PD activity in mice can affect their metabolic pathways in response to fava beans.

  15. Rare earth elements minimal harvest year variation facilitates robust geographical origin discrimination: The case of PDO "Fava Santorinis".

    PubMed

    Drivelos, Spiros A; Danezis, Georgios P; Haroutounian, Serkos A; Georgiou, Constantinos A

    2016-12-15

    This study examines the trace and rare earth elemental (REE) fingerprint variations of PDO (Protected Designation of Origin) "Fava Santorinis" over three consecutive harvesting years (2011-2013). Classification of samples in harvesting years was studied by performing discriminant analysis (DA), k nearest neighbours (κ-NN), partial least squares (PLS) analysis and probabilistic neural networks (PNN) using rare earth elements and trace metals determined using ICP-MS. DA performed better than κ-NN, producing 100% discrimination using trace elements and 79% using REEs. PLS was found to be superior to PNN, achieving 99% and 90% classification for trace and REEs, respectively, while PNN achieved 96% and 71% classification for trace and REEs, respectively. The information obtained using REEs did not enhance classification, indicating that REEs vary minimally per harvesting year, providing robust geographical origin discrimination. The results show that seasonal patterns can occur in the elemental composition of "Fava Santorinis", probably reflecting seasonality of climate. PMID:27451177

  16. Rare earth elements minimal harvest year variation facilitates robust geographical origin discrimination: The case of PDO "Fava Santorinis".

    PubMed

    Drivelos, Spiros A; Danezis, Georgios P; Haroutounian, Serkos A; Georgiou, Constantinos A

    2016-12-15

    This study examines the trace and rare earth elemental (REE) fingerprint variations of PDO (Protected Designation of Origin) "Fava Santorinis" over three consecutive harvesting years (2011-2013). Classification of samples in harvesting years was studied by performing discriminant analysis (DA), k nearest neighbours (κ-NN), partial least squares (PLS) analysis and probabilistic neural networks (PNN) using rare earth elements and trace metals determined using ICP-MS. DA performed better than κ-NN, producing 100% discrimination using trace elements and 79% using REEs. PLS was found to be superior to PNN, achieving 99% and 90% classification for trace and REEs, respectively, while PNN achieved 96% and 71% classification for trace and REEs, respectively. The information obtained using REEs did not enhance classification, indicating that REEs vary minimally per harvesting year, providing robust geographical origin discrimination. The results show that seasonal patterns can occur in the elemental composition of "Fava Santorinis", probably reflecting seasonality of climate.

  17. Treated fava bean (Vicia faba var. minor) as substitute for soybean meal in diet of early phase laying hens: egg-laying performance and egg quality.

    PubMed

    Laudadio, V; Tufarelli, V

    2010-10-01

    The objective of this study was to determine the effect of dietary dehulled-micronized fava bean (Vicia faba var. minor) seed on egg production, egg weight, feed conversion ratio, eggshell quality, and egg yolk color. In this trial, 18-wk-old laying hens in the early phase of production (ISA Brown) were randomly assigned to 2 groups and fed durum wheat middlings-based diets containing soybean or micronized-dehulled fava bean meal as the main protein source. Eggs were collected and weighed daily. Laying performance, egg quality, and feed conversion ratio were evaluated for 10 wk. The only significant effect detected was for feed intake (P<0.05), which was lower in hens fed the diet containing fava bean than for hens fed soybean meal, without however any negative effects on feed efficiency. None of the egg quality parameters studied were influenced by dietary treatment, except for yolk color score that was reduced in hens fed the fava bean diet (P<0.05). We conclude that dehulled-micronized fava beans in the diet did not have a negative influence on productive performance or egg quality of young brown hens.

  18. Treated fava bean (Vicia faba var. minor) as substitute for soybean meal in diet of early phase laying hens: egg-laying performance and egg quality.

    PubMed

    Laudadio, V; Tufarelli, V

    2010-10-01

    The objective of this study was to determine the effect of dietary dehulled-micronized fava bean (Vicia faba var. minor) seed on egg production, egg weight, feed conversion ratio, eggshell quality, and egg yolk color. In this trial, 18-wk-old laying hens in the early phase of production (ISA Brown) were randomly assigned to 2 groups and fed durum wheat middlings-based diets containing soybean or micronized-dehulled fava bean meal as the main protein source. Eggs were collected and weighed daily. Laying performance, egg quality, and feed conversion ratio were evaluated for 10 wk. The only significant effect detected was for feed intake (P<0.05), which was lower in hens fed the diet containing fava bean than for hens fed soybean meal, without however any negative effects on feed efficiency. None of the egg quality parameters studied were influenced by dietary treatment, except for yolk color score that was reduced in hens fed the fava bean diet (P<0.05). We conclude that dehulled-micronized fava beans in the diet did not have a negative influence on productive performance or egg quality of young brown hens. PMID:20852122

  19. New fava bean guard cell signaling mutant impaired in ABA-induced stomatal closure.

    PubMed

    Iwai, Sumio; Shimomura, Naoki; Nakashima, Atsushi; Etoh, Takeomi

    2003-09-01

    We isolated a mutant from Vicia faba L. cv. House Ryousai. It wilts easily under strong light and high temperature conditions, suggesting that its stomatal movement may be disturbed. We determined responses of mutant guard cells to some environmental stimuli. Mutant guard cells demonstrated an impaired ability to respond to ABA in 0.1 mM CaCl(2) and stomata did not close in the presence of up to 1 mM ABA, whereas wild-type stomata closed when exposed to 10 micro M ABA. Elevating external Ca(2+) caused a similar degree of stomatal closure in the wild type and the mutant. A high concentration of CO(2) (700 micro l liter(-1)) induced stomatal closure in the wild type, but not in the mutant. On the basis of these results, we propose the working hypothesis that the mutation occurs in the region downstream of CO(2) and ABA sensing and in the region upstream of Ca(2+) elevation. The mutant is named fia (fava bean impaired in ABA-induced stomatal closure).

  20. New fava bean guard cell signaling mutant impaired in ABA-induced stomatal closure.

    PubMed

    Iwai, Sumio; Shimomura, Naoki; Nakashima, Atsushi; Etoh, Takeomi

    2003-09-01

    We isolated a mutant from Vicia faba L. cv. House Ryousai. It wilts easily under strong light and high temperature conditions, suggesting that its stomatal movement may be disturbed. We determined responses of mutant guard cells to some environmental stimuli. Mutant guard cells demonstrated an impaired ability to respond to ABA in 0.1 mM CaCl(2) and stomata did not close in the presence of up to 1 mM ABA, whereas wild-type stomata closed when exposed to 10 micro M ABA. Elevating external Ca(2+) caused a similar degree of stomatal closure in the wild type and the mutant. A high concentration of CO(2) (700 micro l liter(-1)) induced stomatal closure in the wild type, but not in the mutant. On the basis of these results, we propose the working hypothesis that the mutation occurs in the region downstream of CO(2) and ABA sensing and in the region upstream of Ca(2+) elevation. The mutant is named fia (fava bean impaired in ABA-induced stomatal closure). PMID:14519772

  1. Cytosolic Concentration of Ca2+ Regulates the Plasma Membrane H+-ATPase in Guard Cells of Fava Bean.

    PubMed

    Kinoshita, T.; Nishimura, M.; Shimazaki, Ki.

    1995-08-01

    Opening of the stomata is driven by the light-activated plasma membrane proton pumping ATPase, although the activation and inactivation mechanism of the enzyme is not known. In this study, we show that the H+-ATPase in guard cells is reversibly inhibited by Ca2+ at physiological concentrations. Isolated microsomal membranes of guard cell protoplasts from fava bean exhibited vanadate-sensitive, ATP-dependent proton pumping. The activity was inhibited almost completely by 1 [mu]M Ca2+ with a half-inhibitory concentration at 0.3 [mu]M and was restored immediately by the addition of 1,2-bis(2-aminophenoxy)ethane N,N,N[prime],N[prime]-tetraacetic acid, a calcium chelating reagent. Similar reversible inhibition by Ca2+ was shown by the generation of electrical potential in the membranes. Activity of ATP hydrolysis was inhibited similarly by Ca2+ in the same membrane preparations. The addition of 1,2-bis(2-aminophenoxy)ethane N,N,N[prime],N[prime]-tetraacetic acid and EGTA, Ca2+ chelators, to epidermal peels of fava bean induced stomatal opening in the dark, and the opening was suppressed by vanadate. This suggests that the lowered cytosolic Ca2+ activated the proton pump in vivo and that the activated pump elicited stomatal opening. Inhibition of H+-ATPase by Ca2+ may depolarize the membrane potential and could be a key step in the process of stomatal closing through activation of the anion channels. Furthermore, similar inhibition of the proton pumping and ATP hydrolysis by Ca2+ was found in isolated plasma membranes of mesophyll cells of fava bean. These results suggest that Ca2+ regulates the activity of plasma membrane H+-ATPases in higher plant cells, thereby modulating stomatal movement and other cellular processes in plants.

  2. Cytosolic Concentration of Ca2+ Regulates the Plasma Membrane H+-ATPase in Guard Cells of Fava Bean.

    PubMed

    Kinoshita, T.; Nishimura, M.; Shimazaki, Ki.

    1995-08-01

    Opening of the stomata is driven by the light-activated plasma membrane proton pumping ATPase, although the activation and inactivation mechanism of the enzyme is not known. In this study, we show that the H+-ATPase in guard cells is reversibly inhibited by Ca2+ at physiological concentrations. Isolated microsomal membranes of guard cell protoplasts from fava bean exhibited vanadate-sensitive, ATP-dependent proton pumping. The activity was inhibited almost completely by 1 [mu]M Ca2+ with a half-inhibitory concentration at 0.3 [mu]M and was restored immediately by the addition of 1,2-bis(2-aminophenoxy)ethane N,N,N[prime],N[prime]-tetraacetic acid, a calcium chelating reagent. Similar reversible inhibition by Ca2+ was shown by the generation of electrical potential in the membranes. Activity of ATP hydrolysis was inhibited similarly by Ca2+ in the same membrane preparations. The addition of 1,2-bis(2-aminophenoxy)ethane N,N,N[prime],N[prime]-tetraacetic acid and EGTA, Ca2+ chelators, to epidermal peels of fava bean induced stomatal opening in the dark, and the opening was suppressed by vanadate. This suggests that the lowered cytosolic Ca2+ activated the proton pump in vivo and that the activated pump elicited stomatal opening. Inhibition of H+-ATPase by Ca2+ may depolarize the membrane potential and could be a key step in the process of stomatal closing through activation of the anion channels. Furthermore, similar inhibition of the proton pumping and ATP hydrolysis by Ca2+ was found in isolated plasma membranes of mesophyll cells of fava bean. These results suggest that Ca2+ regulates the activity of plasma membrane H+-ATPases in higher plant cells, thereby modulating stomatal movement and other cellular processes in plants. PMID:12242406

  3. Effects of ABA and CaCl₂ on GABA accumulation in fava bean germinating under hypoxia-NaCl stress.

    PubMed

    Yang, Runqiang; Hui, Qianru; Gu, Zhenxin

    2016-01-01

    Effects of exogenous abscisic acid (ABA) and CaCl2 on γ-aminobutyric acid (GABA) accumulation of germinated fava bean under hypoxia-NaCl stress were investigated. Exogenous ABA resulted in the enhancement of glutamate decarboxylase (GAD) and diamine oxidase (DAO) activity as well as GABA content in cotyledon and shoot. CaCl2 increased both enzyme activities in shoot and GABA content in cotyledon and shoot. ABA downregulated GAD expression in cotyledon and radicle, while upregulated that in shoot; it also upregulated DAO expression in each organ. CaCl2 upregulated GAD expression in cotyledon, while downregulated that in radicle. However, it upregulated DAO expression in shoot, downregulated that in radicle. ABA inhibitor fluridon and ethylenediaminetetraacetic acid inhibited GAD and DAO activities significantly so that inhibited GABA accumulation through reducing ABA biosynthesis and chelating Ca(2+), respectively. However, they upregulated GAD and DAO expression in varying degrees. These results indicate that ABA and Ca(2+) participate in GABA biosynthesis in fava bean during germination under hypoxia-NaCl stress.

  4. Effects of ABA and CaCl₂ on GABA accumulation in fava bean germinating under hypoxia-NaCl stress.

    PubMed

    Yang, Runqiang; Hui, Qianru; Gu, Zhenxin

    2016-01-01

    Effects of exogenous abscisic acid (ABA) and CaCl2 on γ-aminobutyric acid (GABA) accumulation of germinated fava bean under hypoxia-NaCl stress were investigated. Exogenous ABA resulted in the enhancement of glutamate decarboxylase (GAD) and diamine oxidase (DAO) activity as well as GABA content in cotyledon and shoot. CaCl2 increased both enzyme activities in shoot and GABA content in cotyledon and shoot. ABA downregulated GAD expression in cotyledon and radicle, while upregulated that in shoot; it also upregulated DAO expression in each organ. CaCl2 upregulated GAD expression in cotyledon, while downregulated that in radicle. However, it upregulated DAO expression in shoot, downregulated that in radicle. ABA inhibitor fluridon and ethylenediaminetetraacetic acid inhibited GAD and DAO activities significantly so that inhibited GABA accumulation through reducing ABA biosynthesis and chelating Ca(2+), respectively. However, they upregulated GAD and DAO expression in varying degrees. These results indicate that ABA and Ca(2+) participate in GABA biosynthesis in fava bean during germination under hypoxia-NaCl stress. PMID:26644273

  5. An Abscisic Acid-Activated and Calcium-Independent Protein Kinase from Guard Cells of Fava Bean.

    PubMed

    Li, J.; Assmann, S. M.

    1996-12-01

    Abscisic acid (ABA) regulation of stomatal aperture is known to involve both Ca2+-dependent and Ca2+-independent signal transduction pathways. Electrophysiological studies suggest that protein phosphorylation is involved in ABA action in guard cells. Using biochemical approaches, we identified an ABA-activated and Ca2+- independent protein kinase (AAPK) from guard cell protoplasts of fava bean. Autophosphorylation of AAPK was rapidly (~1 min) activated by ABA in a Ca2+- independent manner. ABA-activated autophosphorylation of AAPK occurred on serine but not on tyrosine residues and appeared to be guard cell specific. AAPK phosphorylated histone type III-S on serine and threonine residues, and its activity toward histone type III-S was markedly stimulated in ABA-treated guard cell protoplasts. Our results suggest that AAPK may play an important role in the Ca2+-independent ABA signaling pathways of guard cells.

  6. An Abscisic Acid-Activated and Calcium-Independent Protein Kinase from Guard Cells of Fava Bean.

    PubMed

    Li, J.; Assmann, S. M.

    1996-12-01

    Abscisic acid (ABA) regulation of stomatal aperture is known to involve both Ca2+-dependent and Ca2+-independent signal transduction pathways. Electrophysiological studies suggest that protein phosphorylation is involved in ABA action in guard cells. Using biochemical approaches, we identified an ABA-activated and Ca2+- independent protein kinase (AAPK) from guard cell protoplasts of fava bean. Autophosphorylation of AAPK was rapidly (~1 min) activated by ABA in a Ca2+- independent manner. ABA-activated autophosphorylation of AAPK occurred on serine but not on tyrosine residues and appeared to be guard cell specific. AAPK phosphorylated histone type III-S on serine and threonine residues, and its activity toward histone type III-S was markedly stimulated in ABA-treated guard cell protoplasts. Our results suggest that AAPK may play an important role in the Ca2+-independent ABA signaling pathways of guard cells. PMID:12239380

  7. An Abscisic Acid-Activated and Calcium-Independent Protein Kinase from Guard Cells of Fava Bean.

    PubMed Central

    Li, J.; Assmann, S. M.

    1996-01-01

    Abscisic acid (ABA) regulation of stomatal aperture is known to involve both Ca2+-dependent and Ca2+-independent signal transduction pathways. Electrophysiological studies suggest that protein phosphorylation is involved in ABA action in guard cells. Using biochemical approaches, we identified an ABA-activated and Ca2+- independent protein kinase (AAPK) from guard cell protoplasts of fava bean. Autophosphorylation of AAPK was rapidly (~1 min) activated by ABA in a Ca2+- independent manner. ABA-activated autophosphorylation of AAPK occurred on serine but not on tyrosine residues and appeared to be guard cell specific. AAPK phosphorylated histone type III-S on serine and threonine residues, and its activity toward histone type III-S was markedly stimulated in ABA-treated guard cell protoplasts. Our results suggest that AAPK may play an important role in the Ca2+-independent ABA signaling pathways of guard cells. PMID:12239380

  8. GABA shunt and polyamine degradation pathway on γ-aminobutyric acid accumulation in germinating fava bean (Vicia faba L.) under hypoxia.

    PubMed

    Yang, Runqiang; Guo, Qianghui; Gu, Zhenxin

    2013-01-01

    GABA shunt and polyamine degradation pathway on γ-aminobutyric acid (GABA) accumulation in germinating fava bean under hypoxia was investigated. GABA content, GAD and DAO activity were significantly increased under hypoxia treatment. Glu and polyamine contents enhanced largely and thus supplied as sufficient substrates for GABA formation. In contrast, GABA content decreased, mainly in the embryo, after removing the hypoxia stress. DAO activity, Glu and polyamines contents decreased, while an increment of GAD activity was observed. This indicated that GAD activity can be not only regulated by hypoxia, but by the rapid growth of embryo after the recovery from hypoxia stress. When treated with AG, DAO activity was almost inhibited completely, and the GABA content decreased by 32.96% and 32.07% after treated for 3 and 5 days, respectively. Hence, it can be inferred that about 30% of GABA formed in germinating fava bean under hypoxia was supplied by polyamine degradation pathway. PMID:23017406

  9. GABA shunt and polyamine degradation pathway on γ-aminobutyric acid accumulation in germinating fava bean (Vicia faba L.) under hypoxia.

    PubMed

    Yang, Runqiang; Guo, Qianghui; Gu, Zhenxin

    2013-01-01

    GABA shunt and polyamine degradation pathway on γ-aminobutyric acid (GABA) accumulation in germinating fava bean under hypoxia was investigated. GABA content, GAD and DAO activity were significantly increased under hypoxia treatment. Glu and polyamine contents enhanced largely and thus supplied as sufficient substrates for GABA formation. In contrast, GABA content decreased, mainly in the embryo, after removing the hypoxia stress. DAO activity, Glu and polyamines contents decreased, while an increment of GAD activity was observed. This indicated that GAD activity can be not only regulated by hypoxia, but by the rapid growth of embryo after the recovery from hypoxia stress. When treated with AG, DAO activity was almost inhibited completely, and the GABA content decreased by 32.96% and 32.07% after treated for 3 and 5 days, respectively. Hence, it can be inferred that about 30% of GABA formed in germinating fava bean under hypoxia was supplied by polyamine degradation pathway.

  10. Resistance of glucose-6-phosphate dehydrogenase deficiency to malaria: effects of fava bean hydroxypyrimidine glucosides on Plasmodium falciparum growth in culture and on the phagocytosis of infected cells.

    PubMed

    Ginsburg, H; Atamna, H; Shalmiev, G; Kanaani, J; Krugliak, M

    1996-07-01

    The balanced polymorphism of glucose-6-phosphate dehydrogenase deficiency (G6PD-) is believed to have evolved through the selective pressure of malarial combined with consumption of fava beans. The implicated fava bean constituents are the hydroxypyrimidine glucosides vicine and convicine, which upon hydrolysis of their beta-O-glucosidic bond, became protein pro-oxidants. In this work we show that the glucosides inhibit the growth of Plasmodium falciparum, increase the hexose-monophosphate shunt activity and the phagocytosis of malaria-infected erythrocytes. These activities are exacerbated in the presence of beta-glucosidase, implicating their pro-oxidant aglycones in the toxic effect, and are more pronounced in infected G6PD- erythrocytes. These results suggest that G6PD- infected erythrocytes are more susceptible to phagocytic cells, and that fava bean pro-oxidants are more efficiently suppressing parasite propagation in G6PD- erythrocytes, either by directly affecting parasite growth, or by means of enhanced phagocytic elimination of infected cells. The present findings could account for the relative resistance of G6PD- bearers to falciparum malaria, and establish a link between dietary habits and malaria in the selection of the G6PD- genotype.

  11. Comparative study of the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours as affected by pH

    PubMed Central

    Raikos, Vassilios; Neacsu, Madalina; Russell, Wendy; Duthie, Garry

    2014-01-01

    The demand for products of high nutritional value from sustainable sources is growing rapidly in the global food market. In this study, the effect of pH on the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours was investigated and compared with wheat flour. Functional properties included solubility, emulsifying and foaming properties, gelling ability, and water holding capacity (WHC). All flours had minimal solubility at pH 4 and their corresponding values increased with increasing pH. Emulsifying properties were improved at pH 10 for all samples and emulsion stability showed a similar trend. Increasing pH in the range 4–10 enhanced the foaming properties of the flours, particularly buckwheat and hemp. Wheat, green pea, buckwheat, and fava bean were more capable of forming firm gels compared with lupin and hemp, as indicated by least gelling concentrations (LGCs). The ranking of the water binding properties of the different types of flours were lupin>hemp>fava bean>buckwheat>green pea>wheat. Results indicate that underutilized flours from sustainable plant sources could be exploited by the food industry as functional food ingredients or as replacements of wheat flour for various food applications. Depending on the application, flour functionality may be effectively tailored by pH adjustment. PMID:25493199

  12. Inhibitory effect of a fava bean component on the in vitro development of Plasmodium falciparum in normal and glucose-6-phosphate dehydrogenase deficient erythrocytes.

    PubMed

    Golenser, J; Miller, J; Spira, D T; Navok, T; Chevion, M

    1983-03-01

    We examined the hypothesis that G-6-PD deficiency associated with fava bean ingestion confers resistance to malaria by studying the in vitro interactions between malaria parasites (Plasmodium falciparum), human erythrocytes with varying degrees of G-6-PD deficiency, and isouramil (IU), a fava bean extract that is known to cause oxidant stress and hemolysis of G-6-PD-deficient erythrocytes. Untreated G-6-PD-deficient and normal erythrocytes supported the in vitro growth of P. falciparum equally well. However, after pretreatment with IU, G-6-PD-deficient erythrocytes did not support parasite growth in vitro, whereas growth remained high in normal erythrocytes. Parasite growth was proportional to the G-6-PD activity of the IU-treated erythrocytes. In contrast, when parasitized erythrocytes were exposed to IU, parasites even in normal erythrocytes were destroyed. Ring forms were much less sensitive than late trophozoites and schizonts. The results suggest that there are two modes by which IU affects the development of P. falciparum and demonstrate in vitro that G-6-PD deficiency confers resistance against malaria under conditions of fava-bean-associated oxidant stress.

  13. Resistance of glucose-6-phosphate dehydrogenase deficiency to malaria: effects of fava bean hydroxypyrimidine glucosides on Plasmodium falciparum growth in culture and on the phagocytosis of infected cells.

    PubMed

    Ginsburg, H; Atamna, H; Shalmiev, G; Kanaani, J; Krugliak, M

    1996-07-01

    The balanced polymorphism of glucose-6-phosphate dehydrogenase deficiency (G6PD-) is believed to have evolved through the selective pressure of malarial combined with consumption of fava beans. The implicated fava bean constituents are the hydroxypyrimidine glucosides vicine and convicine, which upon hydrolysis of their beta-O-glucosidic bond, became protein pro-oxidants. In this work we show that the glucosides inhibit the growth of Plasmodium falciparum, increase the hexose-monophosphate shunt activity and the phagocytosis of malaria-infected erythrocytes. These activities are exacerbated in the presence of beta-glucosidase, implicating their pro-oxidant aglycones in the toxic effect, and are more pronounced in infected G6PD- erythrocytes. These results suggest that G6PD- infected erythrocytes are more susceptible to phagocytic cells, and that fava bean pro-oxidants are more efficiently suppressing parasite propagation in G6PD- erythrocytes, either by directly affecting parasite growth, or by means of enhanced phagocytic elimination of infected cells. The present findings could account for the relative resistance of G6PD- bearers to falciparum malaria, and establish a link between dietary habits and malaria in the selection of the G6PD- genotype. PMID:8710417

  14. Comparative study of the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours as affected by pH.

    PubMed

    Raikos, Vassilios; Neacsu, Madalina; Russell, Wendy; Duthie, Garry

    2014-11-01

    The demand for products of high nutritional value from sustainable sources is growing rapidly in the global food market. In this study, the effect of pH on the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours was investigated and compared with wheat flour. Functional properties included solubility, emulsifying and foaming properties, gelling ability, and water holding capacity (WHC). All flours had minimal solubility at pH 4 and their corresponding values increased with increasing pH. Emulsifying properties were improved at pH 10 for all samples and emulsion stability showed a similar trend. Increasing pH in the range 4-10 enhanced the foaming properties of the flours, particularly buckwheat and hemp. Wheat, green pea, buckwheat, and fava bean were more capable of forming firm gels compared with lupin and hemp, as indicated by least gelling concentrations (LGCs). The ranking of the water binding properties of the different types of flours were lupin>hemp>fava bean>buckwheat>green pea>wheat. Results indicate that underutilized flours from sustainable plant sources could be exploited by the food industry as functional food ingredients or as replacements of wheat flour for various food applications. Depending on the application, flour functionality may be effectively tailored by pH adjustment. PMID:25493199

  15. Comparative study of the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours as affected by pH.

    PubMed

    Raikos, Vassilios; Neacsu, Madalina; Russell, Wendy; Duthie, Garry

    2014-11-01

    The demand for products of high nutritional value from sustainable sources is growing rapidly in the global food market. In this study, the effect of pH on the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours was investigated and compared with wheat flour. Functional properties included solubility, emulsifying and foaming properties, gelling ability, and water holding capacity (WHC). All flours had minimal solubility at pH 4 and their corresponding values increased with increasing pH. Emulsifying properties were improved at pH 10 for all samples and emulsion stability showed a similar trend. Increasing pH in the range 4-10 enhanced the foaming properties of the flours, particularly buckwheat and hemp. Wheat, green pea, buckwheat, and fava bean were more capable of forming firm gels compared with lupin and hemp, as indicated by least gelling concentrations (LGCs). The ranking of the water binding properties of the different types of flours were lupin>hemp>fava bean>buckwheat>green pea>wheat. Results indicate that underutilized flours from sustainable plant sources could be exploited by the food industry as functional food ingredients or as replacements of wheat flour for various food applications. Depending on the application, flour functionality may be effectively tailored by pH adjustment.

  16. Factors influencing diamine oxidase activity and γ-aminobutyric acid content of fava bean (Vicia faba L.) during germination.

    PubMed

    Yang, Runqiang; Chen, Hui; Gu, Zhenxin

    2011-11-01

    Factors (germination time, spectra, temperature, pH, and chemical inhibitors) influencing diamine oxidase (DAO, EC 1.4.3.6) activity and γ-aminobutyric acid (GABA) content of fava bean (Vicia faba L.) during germination were investigated in this study. DAO activity significantly increased in germinating seeds but varied with different organs. The enzyme activity was higher in shoot than that in cotyledon, hypocotyl, and radicle. When seeds were germinated in the dark, DAO activity was 2.35-, 2.00-, 2.36-, 4.40-, and 1.67-fold of that under white, red, blue, green, and yellow spectra, respectively. The optimum germination temperature and pH value for increasing DAO activity were 30 °C and 3.0, respectively. The DAO activity was inhibited significantly by aminoguanidine and sodium ethylenediamine tetracetate, while it was activated by CuCl(2) and CaCl(2). Germinating at an appropriate temperature and pH, 30% of GABA formation was supplied by DAO. Calcium was related to the regulation of DAO activity and GABA accumulation. PMID:21942768

  17. Factors influencing diamine oxidase activity and γ-aminobutyric acid content of fava bean (Vicia faba L.) during germination.

    PubMed

    Yang, Runqiang; Chen, Hui; Gu, Zhenxin

    2011-11-01

    Factors (germination time, spectra, temperature, pH, and chemical inhibitors) influencing diamine oxidase (DAO, EC 1.4.3.6) activity and γ-aminobutyric acid (GABA) content of fava bean (Vicia faba L.) during germination were investigated in this study. DAO activity significantly increased in germinating seeds but varied with different organs. The enzyme activity was higher in shoot than that in cotyledon, hypocotyl, and radicle. When seeds were germinated in the dark, DAO activity was 2.35-, 2.00-, 2.36-, 4.40-, and 1.67-fold of that under white, red, blue, green, and yellow spectra, respectively. The optimum germination temperature and pH value for increasing DAO activity were 30 °C and 3.0, respectively. The DAO activity was inhibited significantly by aminoguanidine and sodium ethylenediamine tetracetate, while it was activated by CuCl(2) and CaCl(2). Germinating at an appropriate temperature and pH, 30% of GABA formation was supplied by DAO. Calcium was related to the regulation of DAO activity and GABA accumulation.

  18. Unsuspected glucose-6-phosphate dehydrogenase deficiency presenting as symptomatic methemoglobinemia with severe hemolysis after fava bean ingestion in a 6-year-old boy.

    PubMed

    Odièvre, Marie-Hélène; Danékova, Névéna; Mesples, Bettina; Chemouny, Myriam; Couque, Nathalie; Parez, Nathalie; Ducrocq, Rolande; Elion, Jacques

    2011-05-01

    We report the occurrence of symptomatic methemoglobinemia in a previously healthy boy, who presented with severe acute hemolysis after fava bean ingestion. The methemoglobinemia revealed a previously unrecognized glucose-6-phosphate dehydrogenase (G6PD) deficiency. We discuss the pathophysiology of severe methemoglobinemia when associated with acute hemolysis, favism, and the common African G6PD A-variant [G6PD, VAL68MET, ASN126ASP]. In conclusion, screening for G6PD deficiency must be considered in symptomatic methemoglobinemia, especially in young boys, when associated with intravascular hemolysis.

  19. Unsuspected glucose-6-phosphate dehydrogenase deficiency presenting as symptomatic methemoglobinemia with severe hemolysis after fava bean ingestion in a 6-year-old boy.

    PubMed

    Odièvre, Marie-Hélène; Danékova, Névéna; Mesples, Bettina; Chemouny, Myriam; Couque, Nathalie; Parez, Nathalie; Ducrocq, Rolande; Elion, Jacques

    2011-05-01

    We report the occurrence of symptomatic methemoglobinemia in a previously healthy boy, who presented with severe acute hemolysis after fava bean ingestion. The methemoglobinemia revealed a previously unrecognized glucose-6-phosphate dehydrogenase (G6PD) deficiency. We discuss the pathophysiology of severe methemoglobinemia when associated with acute hemolysis, favism, and the common African G6PD A-variant [G6PD, VAL68MET, ASN126ASP]. In conclusion, screening for G6PD deficiency must be considered in symptomatic methemoglobinemia, especially in young boys, when associated with intravascular hemolysis. PMID:21479984

  20. Magnesium Sensitizes Slow Vacuolar Channels to Physiological Cytosolic Calcium and Inhibits Fast Vacuolar Channels in Fava Bean Guard Cell Vacuoles.

    PubMed

    Pei; Ward; Schroeder

    1999-11-01

    Vacuolar ion channels in guard cells play important roles during stomatal movement and are regulated by many factors including Ca(2+), calmodulin, protein kinases, and phosphatases. We report that physiological cytosolic and luminal Mg(2+) levels strongly regulate vacuolar ion channels in fava bean (Vicia faba) guard cells. Luminal Mg(2+) inhibited fast vacuolar (FV) currents with a K(i) of approximately 0.23 mM in a voltage-dependent manner at positive potentials on the cytoplasmic side. Cytosolic Mg(2+) at 1 mM also inhibited FV currents. Furthermore, in the absence of cytosolic Mg(2+), cytosolic Ca(2+) at less than 10 µM did not activate slow vacuolar (SV) currents. However, when cytosolic Mg(2+) was present, submicromolar concentrations of cytosolic Ca(2+) activated SV currents with a K(d) of approximately 227 nM, suggesting a synergistic Mg(2+)-Ca(2+) effect. The activation potential of SV currents was shifted toward physiological potentials in the presence of cytosolic Mg(2+) concentrations. The direction of SV currents could also be changed from outward to both outward and inward currents. Our data predict a model for SV channel regulation, including a cytosolic binding site for Ca(2+) with an affinity in the submicromolar range and a cytosolic low-affinity Mg(2+)-Ca(2+) binding site. SV channels are predicted to contain a third binding site on the vacuolar luminal side, which binds Ca(2+) and is inhibitory. In conclusion, cytosolic Mg(2+) sensitizes SV channels to physiological cytosolic Ca(2+) elevations. Furthermore, we propose that cytosolic and vacuolar Mg(2+) concentrations ensure that FV channels do not function as a continuous vacuolar K(+) leak, which would prohibit stomatal opening.

  1. Evidence for G-Protein Regulation of Inward K+ Channel Current in Guard Cells of Fava Bean.

    PubMed

    Fairley-Grenot, K.; Assmann, S. M.

    1991-09-01

    Recent reports have shown that GTP-binding proteins (G-proteins) are present in plants but have given limited indication as to their site of action. G-proteins in animal cells transduce extracellular signals into intracellular or membrane-mediated events, including the regulation of ion channels. Using whole-cell patch clamp, we provide evidence that a G-protein in guard cells of fava bean regulates the magnitude (and not the kinetics) of inward current through K+-selective ion channels in the plasma membrane. GDP[beta]S (100 to 500 [mu]M) increases inward K+ current, whereas GTP[gamma]S (500 [mu]M) has the opposite effect. The control nucleotides ADP[beta]S and ATP[gamma]S (500 [mu]M) do not affect K+ current. Reduction of inward current by GTP[gamma]S is eliminated in the presence of the Ca2+ chelator, BAPTA (1,2-bis(2-aminophenoxy)ethane-N,N,N[prime],N[prime],-tetraacetic acid) (5 mM). When applied intracellularly, the G-protein regulators, cholera toxin and pertussis toxin, both decrease inward K+ current. The entry of K+ (and anions) into guard cells increases their turgor, opening stomatal pores in the leaf epidermis that allow gas exchange with the environment. Our data suggest the involvement of a G-protein in the inhibition of K+ uptake and stomatal opening. Changes in stomatal aperture, vital to both photosynthesis and plant water status, reflect guard-cell responsiveness to a variety of known environmental signals. The results presented here indicate that, in plants as well as animals, ion channel regulation by environmental stimuli may be mediated by G-proteins.

  2. Evidence for G-Protein Regulation of Inward K+ Channel Current in Guard Cells of Fava Bean.

    PubMed

    Fairley-Grenot, K.; Assmann, S. M.

    1991-09-01

    Recent reports have shown that GTP-binding proteins (G-proteins) are present in plants but have given limited indication as to their site of action. G-proteins in animal cells transduce extracellular signals into intracellular or membrane-mediated events, including the regulation of ion channels. Using whole-cell patch clamp, we provide evidence that a G-protein in guard cells of fava bean regulates the magnitude (and not the kinetics) of inward current through K+-selective ion channels in the plasma membrane. GDP[beta]S (100 to 500 [mu]M) increases inward K+ current, whereas GTP[gamma]S (500 [mu]M) has the opposite effect. The control nucleotides ADP[beta]S and ATP[gamma]S (500 [mu]M) do not affect K+ current. Reduction of inward current by GTP[gamma]S is eliminated in the presence of the Ca2+ chelator, BAPTA (1,2-bis(2-aminophenoxy)ethane-N,N,N[prime],N[prime],-tetraacetic acid) (5 mM). When applied intracellularly, the G-protein regulators, cholera toxin and pertussis toxin, both decrease inward K+ current. The entry of K+ (and anions) into guard cells increases their turgor, opening stomatal pores in the leaf epidermis that allow gas exchange with the environment. Our data suggest the involvement of a G-protein in the inhibition of K+ uptake and stomatal opening. Changes in stomatal aperture, vital to both photosynthesis and plant water status, reflect guard-cell responsiveness to a variety of known environmental signals. The results presented here indicate that, in plants as well as animals, ion channel regulation by environmental stimuli may be mediated by G-proteins. PMID:12324626

  3. Magnesium Sensitizes Slow Vacuolar Channels to Physiological Cytosolic Calcium and Inhibits Fast Vacuolar Channels in Fava Bean Guard Cell Vacuoles.

    PubMed

    Pei; Ward; Schroeder

    1999-11-01

    Vacuolar ion channels in guard cells play important roles during stomatal movement and are regulated by many factors including Ca(2+), calmodulin, protein kinases, and phosphatases. We report that physiological cytosolic and luminal Mg(2+) levels strongly regulate vacuolar ion channels in fava bean (Vicia faba) guard cells. Luminal Mg(2+) inhibited fast vacuolar (FV) currents with a K(i) of approximately 0.23 mM in a voltage-dependent manner at positive potentials on the cytoplasmic side. Cytosolic Mg(2+) at 1 mM also inhibited FV currents. Furthermore, in the absence of cytosolic Mg(2+), cytosolic Ca(2+) at less than 10 µM did not activate slow vacuolar (SV) currents. However, when cytosolic Mg(2+) was present, submicromolar concentrations of cytosolic Ca(2+) activated SV currents with a K(d) of approximately 227 nM, suggesting a synergistic Mg(2+)-Ca(2+) effect. The activation potential of SV currents was shifted toward physiological potentials in the presence of cytosolic Mg(2+) concentrations. The direction of SV currents could also be changed from outward to both outward and inward currents. Our data predict a model for SV channel regulation, including a cytosolic binding site for Ca(2+) with an affinity in the submicromolar range and a cytosolic low-affinity Mg(2+)-Ca(2+) binding site. SV channels are predicted to contain a third binding site on the vacuolar luminal side, which binds Ca(2+) and is inhibitory. In conclusion, cytosolic Mg(2+) sensitizes SV channels to physiological cytosolic Ca(2+) elevations. Furthermore, we propose that cytosolic and vacuolar Mg(2+) concentrations ensure that FV channels do not function as a continuous vacuolar K(+) leak, which would prohibit stomatal opening. PMID:10557247

  4. Affinophoresis of pea lectin and fava bean lectin with an anionic affinophore, bearing rho-aminophenyl-alpha-D-mannoside as an affinity ligand.

    PubMed

    Shimura, K; Kasai, K

    1987-07-29

    Affinophoresis is an electrophoretic separation technique for biological polymers with the aid of an affinophore, which is a macromolecular polyelectrolyte bearing affinity ligands. The affinophore migrates rapidly in an electric field, and consequently the electrophoretic mobility of molecules having an affinity for the ligand is specifically changed. An anionic affinophore-bearing mannosyl residue was synthesized for the affinophoresis of lectins. rho-Aminophenyl-alpha-D-mannopyranoside and aminomethanesulphonic acid were coupled to about one-tenth and one-fifth, respectively, of the carboxyl groups of succinyl-poly-L-lysine with an average degree of polymerization of 120 by the use of a water-soluble carbodiimide. Extracts of seeds of pea (Pisum sativum) or fava bean (Vicia fava) were subjected to two-dimensional agarose gel electrophoresis, in which the first dimension was ordinary agarose gel electrophoresis and the second dimension was affinophoresis with the affinophore. The separated proteins were stained with Coomassie Blue R250. The lectins in both seed extracts were separated from a diagonal line formed by other proteins in the extracts. About 10 ng of the separated pea lectin was detected on a nitrocellulose blot by immunostaining with a horseradish peroxidase-conjugated second antibody.

  5. Data fusion for food authentication. Combining rare earth elements and trace metals to discriminate "Fava Santorinis" from other yellow split peas using chemometric tools.

    PubMed

    Drivelos, Spiros A; Higgins, Kevin; Kalivas, John H; Haroutounian, Serkos A; Georgiou, Constantinos A

    2014-12-15

    "Fava Santorinis", is a protected designation of origin (PDO) yellow split pea species growing only in the island of Santorini in Greece. Due to its nutritional quality and taste, it has gained a high monetary value. Thus, it is prone to adulteration with other yellow split peas. In order to discriminate "Fava Santorinis" from other yellow split peas, four classification methods utilising rare earth elements (REEs) measured through inductively coupled plasma-mass spectrometry (ICP-MS) are studied. The four classification processes are orthogonal projection analysis (OPA), Mahalanobis distance (MD), partial least squares discriminant analysis (PLS-DA) and k nearest neighbours (KNN). Since it is known that trace elements are often useful to determine geographical origin of food products, we further quantitated for trace elements using ICP-MS. Presented in this paper are results using the four classification processes based on the fusion of the REEs data with the trace element data. Overall, the OPA method was found to perform best with up to 100% accuracy using the fused data.

  6. Affinophoresis of pea lectin and fava bean lectin with an anionic affinophore, bearing rho-aminophenyl-alpha-D-mannoside as an affinity ligand.

    PubMed

    Shimura, K; Kasai, K

    1987-07-29

    Affinophoresis is an electrophoretic separation technique for biological polymers with the aid of an affinophore, which is a macromolecular polyelectrolyte bearing affinity ligands. The affinophore migrates rapidly in an electric field, and consequently the electrophoretic mobility of molecules having an affinity for the ligand is specifically changed. An anionic affinophore-bearing mannosyl residue was synthesized for the affinophoresis of lectins. rho-Aminophenyl-alpha-D-mannopyranoside and aminomethanesulphonic acid were coupled to about one-tenth and one-fifth, respectively, of the carboxyl groups of succinyl-poly-L-lysine with an average degree of polymerization of 120 by the use of a water-soluble carbodiimide. Extracts of seeds of pea (Pisum sativum) or fava bean (Vicia fava) were subjected to two-dimensional agarose gel electrophoresis, in which the first dimension was ordinary agarose gel electrophoresis and the second dimension was affinophoresis with the affinophore. The separated proteins were stained with Coomassie Blue R250. The lectins in both seed extracts were separated from a diagonal line formed by other proteins in the extracts. About 10 ng of the separated pea lectin was detected on a nitrocellulose blot by immunostaining with a horseradish peroxidase-conjugated second antibody. PMID:3667759

  7. Biodegradable PELA block copolymers: in vitro degradation and tissue reaction.

    PubMed

    Younes, H; Nataf, P R; Cohn, D; Appelbaum, Y J; Pizov, G; Uretzky, G

    1988-01-01

    Degradation of, and tissue reaction elicited by a series of polyethylene oxide (PEO)/polylactic acid (PLA) PELA block copolymers were studied in vitro and in vivo. In particular, the effect of pH, temperature and enzymatic activity was addressed. The mass loss was faster, the more basic the media, while, expectedly, PELA copolymers degraded faster with the higher temperature. The addition of an enzyme (carboxylic ester hydrolase) had no effect. The degradation process strongly affected the mechanical properties of the materials under investigation, the elongation at break dropping drastically after two days of degradation. After seven days, only gross observation of the extensively degraded samples was possible. The in vivo studies compared the tissue reaction elicited by various PELA copolymers to that evoked by PLA. Evaluation of tissue reaction observed with a PELA sample after sterilization with gamma radiation showed acute inflammation with considerable dispersion of the material, 12 days after implantation. The granulomatous reaction observed with PELA copolymers after ethylene oxide sterilization was identical to the reaction observed with PLA. PMID:3064826

  8. Nutritional value, performance, carcass quality, visceral organ size, and blood clinical chemistry of broiler chicks fed 30% tannin-free fava bean diets.

    PubMed

    Usayran, N N; Sha'ar, H; Barbour, G W; Yau, S K; Maalouf, F; Farran, M T

    2014-08-01

    Two experiments were conducted to evaluate the chemical and nutritional values of 5 tannin-free fava bean (FB) cultivars (FB9, FB10, FB13, FB17, and FB24) on growth, visceral organ size, and blood clinical chemistry of broiler chicks fed a corn-soybean meal 48 (SBM48) diet containing 30% tannin-free FB. In the first experiment, 49 Hy-line roosters, 55 wk of age, were individually precision-fed 30 g of each FB cultivar and soybean meal 44 (SBM44). Protein, methionine, and lysine contents of the FB seeds (0.005% tannin) were 27.7, 0.23, and 1.98% of DM, respectively. The AMEn of all FB cultivars was 2,839 kcal/kg and higher (P < 0.05) than SBM44. The true lysine digestibility of FB10 (94.1) was higher (P < 0.05) than FB9 (89.0%) and FB24 (89.2%), but comparable with the other fava beans. The FB cultivar's true methionine digestibilities were similar among each other and to SBM44. In a battery feeding trial, 6 corn-SBM48 diets containing 0 (control) or 30% of FB9, FB10, FB13, FB17, or FB24 seeds were each fed to Ross 308 1-wk-old male broiler chicks for 14 d. The determined FB nutrient values were used in formulating FB-containing diets. Birds fed FB-containing diets had better (P < 0.05) weight gain and feed conversion than those of the control. When compared with the control birds, relative weights of abdominal fat pad and liver were reduced (P < 0.05) by 30% inclusion of all dietary FB varieties, except for FB17 and FB13, respectively. Broiler chicks fed the FB13 diet had plasma thrombocyte and white blood cell (WBC) differential counts higher (P < 0.05) than those fed the FB10 diet and WBC count higher (P < 0.05) than the birds fed the FB17 diet. In conclusion, tannin-free FB was lower in protein, methionine, and lysine, but higher in AMEn, compared with SBM44. Moreover, FB seeds, especially FB10, can be included in a broiler chick diet with no adverse effects on performance, but FB13 increased WBC count.

  9. Nutritional value, performance, carcass quality, visceral organ size, and blood clinical chemistry of broiler chicks fed 30% tannin-free fava bean diets.

    PubMed

    Usayran, N N; Sha'ar, H; Barbour, G W; Yau, S K; Maalouf, F; Farran, M T

    2014-08-01

    Two experiments were conducted to evaluate the chemical and nutritional values of 5 tannin-free fava bean (FB) cultivars (FB9, FB10, FB13, FB17, and FB24) on growth, visceral organ size, and blood clinical chemistry of broiler chicks fed a corn-soybean meal 48 (SBM48) diet containing 30% tannin-free FB. In the first experiment, 49 Hy-line roosters, 55 wk of age, were individually precision-fed 30 g of each FB cultivar and soybean meal 44 (SBM44). Protein, methionine, and lysine contents of the FB seeds (0.005% tannin) were 27.7, 0.23, and 1.98% of DM, respectively. The AMEn of all FB cultivars was 2,839 kcal/kg and higher (P < 0.05) than SBM44. The true lysine digestibility of FB10 (94.1) was higher (P < 0.05) than FB9 (89.0%) and FB24 (89.2%), but comparable with the other fava beans. The FB cultivar's true methionine digestibilities were similar among each other and to SBM44. In a battery feeding trial, 6 corn-SBM48 diets containing 0 (control) or 30% of FB9, FB10, FB13, FB17, or FB24 seeds were each fed to Ross 308 1-wk-old male broiler chicks for 14 d. The determined FB nutrient values were used in formulating FB-containing diets. Birds fed FB-containing diets had better (P < 0.05) weight gain and feed conversion than those of the control. When compared with the control birds, relative weights of abdominal fat pad and liver were reduced (P < 0.05) by 30% inclusion of all dietary FB varieties, except for FB17 and FB13, respectively. Broiler chicks fed the FB13 diet had plasma thrombocyte and white blood cell (WBC) differential counts higher (P < 0.05) than those fed the FB10 diet and WBC count higher (P < 0.05) than the birds fed the FB17 diet. In conclusion, tannin-free FB was lower in protein, methionine, and lysine, but higher in AMEn, compared with SBM44. Moreover, FB seeds, especially FB10, can be included in a broiler chick diet with no adverse effects on performance, but FB13 increased WBC count. PMID:24894523

  10. A role for sugar transporters during seed development: molecular characterization of a hexose and a sucrose carrier in fava bean seeds.

    PubMed

    Weber, H; Borisjuk, L; Heim, U; Sauer, N; Wobus, U

    1997-06-01

    To analyze sugar transport processes during seed development of fava bean, we cloned cDNAs encoding one sucrose and one hexose transporter, designated VfSUT1 and VfSTP1, respectively. sugar uptake activity was confirmed after heterologous expression in yeast. Gene expression was studied in relation to seed development. Transcripts were detected in both vegetative and seed tissues. In the embryo, VfSUT1 and VfSTP1 mRNAs were detected only in epidermal cells, but in a different temporal and spatial pattern. VfSTP1 mRNA accumulates during the midcotyledon stage in epidermal cells covering the mitotically active parenchyma, whereas the VfSUT1 transcript was specific to outer epidermal cells showing transfer cell morphology and covering the storage parenchyma. Transfer cells developed at the contact area of the cotyledonary epidermis and the seed coat, starting first at the early cotyledon stage and subsequently spreading to the abaxial region at the late cotyledon stage. Feeding high concentrations of sugars suppressed both VfSUT1 expression and transfer cell differentiation in vitro, suggesting a control by carbohydrate availability.

  11. Increased red cell calcium, decreased calcium adenosine triphosphatase, and altered membrane proteins during fava bean hemolysis in glucose-6-phosphate dehydrogenase-deficient (Mediterranean variant) individuals.

    PubMed

    Turrini, F; Naitana, A; Mannuzzu, L; Pescarmona, G; Arese, P

    1985-08-01

    RBCs from four glucose-6-phosphate dehydrogenase (G6PD)-deficient (Mediterranean variant) subjects were studied during fava bean hemolysis. In the density-fractionated RBC calcium level, Ca2+-ATPase activity, reduced glutathione level, and ghost protein pattern were studied. In the bottom fraction, containing most heavily damaged RBCs, calcium level ranged from 143 to 244 mumol/L RBCs (healthy G6PD-deficient controls: 17 +/- 5 mumol/L RBCs). The Ca2+-ATPase activity ranged from 0.87 to 1.84 mumol ATP consumed/g Hb/min (healthy G6PD-deficient controls: 2.27 +/- 0.4). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of ghosts showed: (1) the presence of high mol wt aggregates (in three cases they were reduced by dithioerythritol; in one case, only partial reduction was possible); (2) the presence of multiple, scattered new bands; and (3) the reduction of band 3. Oxidant-mediated damage to active calcium extrusion, hypothetically associated with increased calcium permeability, may explain the large increase in calcium levels. They, in turn, could activate calcium-dependent protease activity, giving rise to the profound changes in the ghost protein pattern.

  12. A role for sugar transporters during seed development: molecular characterization of a hexose and a sucrose carrier in fava bean seeds.

    PubMed

    Weber, H; Borisjuk, L; Heim, U; Sauer, N; Wobus, U

    1997-06-01

    To analyze sugar transport processes during seed development of fava bean, we cloned cDNAs encoding one sucrose and one hexose transporter, designated VfSUT1 and VfSTP1, respectively. sugar uptake activity was confirmed after heterologous expression in yeast. Gene expression was studied in relation to seed development. Transcripts were detected in both vegetative and seed tissues. In the embryo, VfSUT1 and VfSTP1 mRNAs were detected only in epidermal cells, but in a different temporal and spatial pattern. VfSTP1 mRNA accumulates during the midcotyledon stage in epidermal cells covering the mitotically active parenchyma, whereas the VfSUT1 transcript was specific to outer epidermal cells showing transfer cell morphology and covering the storage parenchyma. Transfer cells developed at the contact area of the cotyledonary epidermis and the seed coat, starting first at the early cotyledon stage and subsequently spreading to the abaxial region at the late cotyledon stage. Feeding high concentrations of sugars suppressed both VfSUT1 expression and transfer cell differentiation in vitro, suggesting a control by carbohydrate availability. PMID:9212465

  13. Seed coat-associated invertases of fava bean control both unloading and storage functions: cloning of cDNAs and cell type-specific expression.

    PubMed

    Weber, H; Borisjuk, L; Heim, U; Buchner, P; Wobus, U

    1995-11-01

    We have studied the molecular physiology of photosynthate unloading and partitioning during seed development of fava bean (Vicia faba). During the prestorage phase, high levels of hexoses in the cotyledons and the apoplastic endospermal space are correlated with activity of cell wall-bound invertase in the seed coat. Three cDNAs were cloned. Sequence comparison revealed genes putatively encoding one soluble and two cell wall-bound isoforms of invertase. Expression was studied in different organs and tissues of developing seeds by RNA gel analysis, in situ hybridization, enzyme assay, and enzyme activity staining. One extracellular invertase gene is expressed during the prestorage phase in the thin-walled parenchyma of the seed coat, a region known to be the site of photoassimilate unloading. We propose a model for an invertase-mediated unloading process during early seed development and the regulation of cotyledonary sucrose metabolism. After unloading from the seed coat, sucrose is hydrolyzed by cell wall-bound invertases. Thus, invertase contributes to establish sink strength in young seeds. The resultant hexoses are loaded into the cotyledons and control carbohydrate partitioning via an influence on the sucrose synthase/sucrose-phosphate synthase pathway. The developmentally regulated degradation of the thin-walled parenchyma expressing the invertase apparently initiates the storage phase. This is characterized by a switch to a low sucrose/hexoses ratio. Feeding hexoses to storage-phase cotyledons in vitro increases the sucrose-phosphate synthase/sucrose synthase ratio and changes carbohydrate partitioning in favor of sucrose. Concomitantly, the transcript level of the major storage product legumin B is downregulated.

  14. Synthesis of high-affinity, hydrophobic monosaccharide derivatives and study of their interaction with concanavalin A, the pea, the lentil, and fava bean lectins.

    PubMed

    Loganathan, D; Osborne, S E; Glick, G D; Goldstein, I J

    1992-12-01

    Concanavalin A (Con A) and agglutinins from the pea (PSA), lentil (LCH), and fava bean (VFA) constitute a group of D-mannose/D-glucose binding legume lectins. In addition to their sugar binding specificity, these lectins also contain sites that bind hydrophobic ligands. The present study explores a class of nonpolar binding sites reportedly present adjacent to the carbohydrate binding site in PSA, LCH, and VFA. A series of 2-O- and 3-O-substituted nitrobenzoyl and nitrobenzyl derivatives of methyl alpha-D-glucopyranoside and methyl alpha-D-mannopyranoside were synthesized. Evaluation of their binding to Con A, PSA, LCH, and VFA was carried out by the technique of hapten inhibition of precipitation reaction. The hapten inhibition assay results reveal that the presence of a methyl or methylene group at the O-2 or O-3 position of the sugar is essential for hydrophobic interaction with PSA, LCH, and VFA. The substitution of methyl by nitrobenzyl leads to enhanced binding (1.7-16.7 times for the 2-O-substituted compounds and 7.9-40.5 times for the 3-O-substituted compounds) with the m-nitrobenzyl group contributing to maximum binding. A hydrophobic interaction is also involved between Con A and 2-O-nitrobenzyl derivatives, resulting in enhanced binding, but the corresponding 3-O-isomers bind poorly due probably to steric reasons. These results may be rationalized on the basis of the recently published X-ray data of Con A and VFA. The nitrobenzyl derivatives, after transformation to their azido analogs, have potential applications in the photoaffinity labeling of these lectins.

  15. Analysis of a soluble calmodulin binding protein from fava bean roots: identification of glutamate decarboxylase as a calmodulin-activated enzyme.

    PubMed

    Ling, V; Snedden, W A; Shelp, B J; Assmann, S M

    1994-08-01

    The identity of a soluble 62-kD Ca(2+)-dependent calmodulin binding protein (CaM-BP) from fava bean seedlings was determined. Using 125I-CaM overlay assays, a class of soluble CaM-BPs was detected in extracts of tissues comprising the axis of 1.5-week-old seedlings, excluding the root tip and emergent leaves. The size of these CaM-BPs was not uniform within all parts of the plant; the apparent molecular masses were 62 kD in roots, 60 kD in stems, and 64 kD in nodules. The root 62-kD CaM-BP was purified, and internal microsequence analysis was performed on the protein. A tryptic peptide derived from the CaM-BP consisted of a 13-residue sequence corresponding to a highly conserved region of glutamate decarboxylase (GAD), an enzyme that catalyzes the alpha-decarboxylation of glutamate to form the stress-related metabolite gamma-aminobutyrate. Activity assays of partially purified, desalted, root GAD revealed a 50% stimulation by the addition of 100 microM Ca2+, a 100% stimulation by the addition of 100 microM Ca2+ plus 100 nM CaM, and no appreciable stimulation by CaM in the absence of added Ca2+. The demonstration that plant GAD is a Ca(2+)-CaM-stimulated enzyme provides a model in which stress-linked metabolism is modulated by a Ca(2+)-mediated signal transduction pathway.

  16. Synthesis of high-affinity, hydrophobic monosaccharide derivatives and study of their interaction with concanavalin A, the pea, the lentil, and fava bean lectins.

    PubMed

    Loganathan, D; Osborne, S E; Glick, G D; Goldstein, I J

    1992-12-01

    Concanavalin A (Con A) and agglutinins from the pea (PSA), lentil (LCH), and fava bean (VFA) constitute a group of D-mannose/D-glucose binding legume lectins. In addition to their sugar binding specificity, these lectins also contain sites that bind hydrophobic ligands. The present study explores a class of nonpolar binding sites reportedly present adjacent to the carbohydrate binding site in PSA, LCH, and VFA. A series of 2-O- and 3-O-substituted nitrobenzoyl and nitrobenzyl derivatives of methyl alpha-D-glucopyranoside and methyl alpha-D-mannopyranoside were synthesized. Evaluation of their binding to Con A, PSA, LCH, and VFA was carried out by the technique of hapten inhibition of precipitation reaction. The hapten inhibition assay results reveal that the presence of a methyl or methylene group at the O-2 or O-3 position of the sugar is essential for hydrophobic interaction with PSA, LCH, and VFA. The substitution of methyl by nitrobenzyl leads to enhanced binding (1.7-16.7 times for the 2-O-substituted compounds and 7.9-40.5 times for the 3-O-substituted compounds) with the m-nitrobenzyl group contributing to maximum binding. A hydrophobic interaction is also involved between Con A and 2-O-nitrobenzyl derivatives, resulting in enhanced binding, but the corresponding 3-O-isomers bind poorly due probably to steric reasons. These results may be rationalized on the basis of the recently published X-ray data of Con A and VFA. The nitrobenzyl derivatives, after transformation to their azido analogs, have potential applications in the photoaffinity labeling of these lectins. PMID:1444465

  17. Analysis of a soluble calmodulin binding protein from fava bean roots: identification of glutamate decarboxylase as a calmodulin-activated enzyme.

    PubMed

    Ling, V; Snedden, W A; Shelp, B J; Assmann, S M

    1994-08-01

    The identity of a soluble 62-kD Ca(2+)-dependent calmodulin binding protein (CaM-BP) from fava bean seedlings was determined. Using 125I-CaM overlay assays, a class of soluble CaM-BPs was detected in extracts of tissues comprising the axis of 1.5-week-old seedlings, excluding the root tip and emergent leaves. The size of these CaM-BPs was not uniform within all parts of the plant; the apparent molecular masses were 62 kD in roots, 60 kD in stems, and 64 kD in nodules. The root 62-kD CaM-BP was purified, and internal microsequence analysis was performed on the protein. A tryptic peptide derived from the CaM-BP consisted of a 13-residue sequence corresponding to a highly conserved region of glutamate decarboxylase (GAD), an enzyme that catalyzes the alpha-decarboxylation of glutamate to form the stress-related metabolite gamma-aminobutyrate. Activity assays of partially purified, desalted, root GAD revealed a 50% stimulation by the addition of 100 microM Ca2+, a 100% stimulation by the addition of 100 microM Ca2+ plus 100 nM CaM, and no appreciable stimulation by CaM in the absence of added Ca2+. The demonstration that plant GAD is a Ca(2+)-CaM-stimulated enzyme provides a model in which stress-linked metabolism is modulated by a Ca(2+)-mediated signal transduction pathway. PMID:7919983

  18. Analysis of a soluble calmodulin binding protein from fava bean roots: identification of glutamate decarboxylase as a calmodulin-activated enzyme.

    PubMed Central

    Ling, V; Snedden, W A; Shelp, B J; Assmann, S M

    1994-01-01

    The identity of a soluble 62-kD Ca(2+)-dependent calmodulin binding protein (CaM-BP) from fava bean seedlings was determined. Using 125I-CaM overlay assays, a class of soluble CaM-BPs was detected in extracts of tissues comprising the axis of 1.5-week-old seedlings, excluding the root tip and emergent leaves. The size of these CaM-BPs was not uniform within all parts of the plant; the apparent molecular masses were 62 kD in roots, 60 kD in stems, and 64 kD in nodules. The root 62-kD CaM-BP was purified, and internal microsequence analysis was performed on the protein. A tryptic peptide derived from the CaM-BP consisted of a 13-residue sequence corresponding to a highly conserved region of glutamate decarboxylase (GAD), an enzyme that catalyzes the alpha-decarboxylation of glutamate to form the stress-related metabolite gamma-aminobutyrate. Activity assays of partially purified, desalted, root GAD revealed a 50% stimulation by the addition of 100 microM Ca2+, a 100% stimulation by the addition of 100 microM Ca2+ plus 100 nM CaM, and no appreciable stimulation by CaM in the absence of added Ca2+. The demonstration that plant GAD is a Ca(2+)-CaM-stimulated enzyme provides a model in which stress-linked metabolism is modulated by a Ca(2+)-mediated signal transduction pathway. PMID:7919983

  19. Seed coat-associated invertases of fava bean control both unloading and storage functions: cloning of cDNAs and cell type-specific expression.

    PubMed Central

    Weber, H; Borisjuk, L; Heim, U; Buchner, P; Wobus, U

    1995-01-01

    We have studied the molecular physiology of photosynthate unloading and partitioning during seed development of fava bean (Vicia faba). During the prestorage phase, high levels of hexoses in the cotyledons and the apoplastic endospermal space are correlated with activity of cell wall-bound invertase in the seed coat. Three cDNAs were cloned. Sequence comparison revealed genes putatively encoding one soluble and two cell wall-bound isoforms of invertase. Expression was studied in different organs and tissues of developing seeds by RNA gel analysis, in situ hybridization, enzyme assay, and enzyme activity staining. One extracellular invertase gene is expressed during the prestorage phase in the thin-walled parenchyma of the seed coat, a region known to be the site of photoassimilate unloading. We propose a model for an invertase-mediated unloading process during early seed development and the regulation of cotyledonary sucrose metabolism. After unloading from the seed coat, sucrose is hydrolyzed by cell wall-bound invertases. Thus, invertase contributes to establish sink strength in young seeds. The resultant hexoses are loaded into the cotyledons and control carbohydrate partitioning via an influence on the sucrose synthase/sucrose-phosphate synthase pathway. The developmentally regulated degradation of the thin-walled parenchyma expressing the invertase apparently initiates the storage phase. This is characterized by a switch to a low sucrose/hexoses ratio. Feeding hexoses to storage-phase cotyledons in vitro increases the sucrose-phosphate synthase/sucrose synthase ratio and changes carbohydrate partitioning in favor of sucrose. Concomitantly, the transcript level of the major storage product legumin B is downregulated. PMID:8535137

  20. Seed coat-associated invertases of fava bean control both unloading and storage functions: cloning of cDNAs and cell type-specific expression.

    PubMed

    Weber, H; Borisjuk, L; Heim, U; Buchner, P; Wobus, U

    1995-11-01

    We have studied the molecular physiology of photosynthate unloading and partitioning during seed development of fava bean (Vicia faba). During the prestorage phase, high levels of hexoses in the cotyledons and the apoplastic endospermal space are correlated with activity of cell wall-bound invertase in the seed coat. Three cDNAs were cloned. Sequence comparison revealed genes putatively encoding one soluble and two cell wall-bound isoforms of invertase. Expression was studied in different organs and tissues of developing seeds by RNA gel analysis, in situ hybridization, enzyme assay, and enzyme activity staining. One extracellular invertase gene is expressed during the prestorage phase in the thin-walled parenchyma of the seed coat, a region known to be the site of photoassimilate unloading. We propose a model for an invertase-mediated unloading process during early seed development and the regulation of cotyledonary sucrose metabolism. After unloading from the seed coat, sucrose is hydrolyzed by cell wall-bound invertases. Thus, invertase contributes to establish sink strength in young seeds. The resultant hexoses are loaded into the cotyledons and control carbohydrate partitioning via an influence on the sucrose synthase/sucrose-phosphate synthase pathway. The developmentally regulated degradation of the thin-walled parenchyma expressing the invertase apparently initiates the storage phase. This is characterized by a switch to a low sucrose/hexoses ratio. Feeding hexoses to storage-phase cotyledons in vitro increases the sucrose-phosphate synthase/sucrose synthase ratio and changes carbohydrate partitioning in favor of sucrose. Concomitantly, the transcript level of the major storage product legumin B is downregulated. PMID:8535137

  1. 4-Chloro-6-methoxyindole is the precursor of a potent mutagen (4-chloro-6-methoxy-2-hydroxy-1-nitroso-indolin-3-one oxime) that forms during nitrosation of the fava bean (Vicia faba).

    PubMed

    Yang, D; Tannenbaum, S R; Büchi, G; Lee, G C

    1984-10-01

    Fava beans (Vicia faba) upon treatment with nitrite under simulated gastric conditions, form a direct-acting bacterial mutagen, comparable in specific activity to the most potent known mutagens for several strains of Salmonella typhimurium. The precursor of the mutagen was isolated and identified as 4-chloro-6-methoxyindole by u.v., i.r., m.s. and n.m.r. The precursor was dechlorinated with NaBH4 and PdCl2 as the catalyst and the product obtained from this reaction was identified as 6-methoxyindole. Since synthetic 4-chloro-6-methoxyindole was not available, structure activity studies were conducted on substituted indoles. Nitrosation of 4-chloroindole closely follows the results for nitrosation of 4-chloro-6-methoxyindole. The major product of nitrosation of 4-chloroindole is 4-chloro-2-hydroxy-N1-nitroso-indolin-3-one oxime. Thus, it appears that the major nitrosation product of 4-chloroindole and of 4-chloro-6-methoxyindole is a stable alpha-hydroxy N-nitroso compound. This is the first reported case of stable alpha-hydroxy N-nitroso compounds. In the presence of N-(1-naphthyl)ethylenediamine dihydrochloride (NEDD), the alpha-hydroxy N-nitroso compound rearranges to an aromatic diazonium ion which couples with the diamine to form an azo dye. Studies on nitrosation kinetics indicate that the nitrosation of indoles are relatively fast reactions. Both the structural and rate studies give strong support to the hypothesis that intragastric nitrosation of fava beans yield the putative gastric carcinogen in the high-risk area in Colombia.

  2. 4-Chloro-6-methoxyindole is the precursor of a potent mutagen (4-chloro-6-methoxy-2-hydroxy-1-nitroso-indolin-3-one oxime) that forms during nitrosation of the fava bean (Vicia faba).

    PubMed

    Yang, D; Tannenbaum, S R; Büchi, G; Lee, G C

    1984-10-01

    Fava beans (Vicia faba) upon treatment with nitrite under simulated gastric conditions, form a direct-acting bacterial mutagen, comparable in specific activity to the most potent known mutagens for several strains of Salmonella typhimurium. The precursor of the mutagen was isolated and identified as 4-chloro-6-methoxyindole by u.v., i.r., m.s. and n.m.r. The precursor was dechlorinated with NaBH4 and PdCl2 as the catalyst and the product obtained from this reaction was identified as 6-methoxyindole. Since synthetic 4-chloro-6-methoxyindole was not available, structure activity studies were conducted on substituted indoles. Nitrosation of 4-chloroindole closely follows the results for nitrosation of 4-chloro-6-methoxyindole. The major product of nitrosation of 4-chloroindole is 4-chloro-2-hydroxy-N1-nitroso-indolin-3-one oxime. Thus, it appears that the major nitrosation product of 4-chloroindole and of 4-chloro-6-methoxyindole is a stable alpha-hydroxy N-nitroso compound. This is the first reported case of stable alpha-hydroxy N-nitroso compounds. In the presence of N-(1-naphthyl)ethylenediamine dihydrochloride (NEDD), the alpha-hydroxy N-nitroso compound rearranges to an aromatic diazonium ion which couples with the diamine to form an azo dye. Studies on nitrosation kinetics indicate that the nitrosation of indoles are relatively fast reactions. Both the structural and rate studies give strong support to the hypothesis that intragastric nitrosation of fava beans yield the putative gastric carcinogen in the high-risk area in Colombia. PMID:6548421

  3. PelA Deacetylase Activity Is Required for Pel Polysaccharide Synthesis in Pseudomonas aeruginosa

    PubMed Central

    Colvin, Kelly M.; Alnabelseya, Noor; Baker, Perrin; Whitney, John C.

    2013-01-01

    The Pel polysaccharide serves as an intercellular adhesin for the formation and maintenance of biofilms in the opportunistic pathogen Pseudomonas aeruginosa. Pel biosynthesis requires the products of a seven-gene operon, pelA-pelG, all of which are necessary for Pel-dependent biofilm formation and Pel-related phenotypes. One of the genes, pelA, encodes a protein with a predicted polysaccharide deacetylase domain. In this work, the role of the putative deacetylase domain in Pel production was examined. We first established that purified recombinant PelA hydrolyzed the pseudosubstrate p-nitrophenyl acetate in vitro, and site-specific mutations of predicted deacetylase active-site residues reduced activity greater than 10-fold. Additionally, these mutants were deficient in Pel-dependent biofilm formation and wrinkly colony morphology in vivo. Subcellular fractionation experiments demonstrate that PelA localizes to both the membrane and periplasmic fractions. Finally, antiserum against the Pel polysaccharide was generated, and PelA deacetylase mutants do not produce Pel-reactive material. Taken together, these results suggest that the deacetylase activity of PelA is important for the production of the Pel polysaccharide. PMID:23504011

  4. Comparison of physicochemical properties of 7S and 11S globulins from pea, fava bean, cowpea, and French bean with those of soybean--French bean 7S globulin exhibits excellent properties.

    PubMed

    Kimura, Aiko; Fukuda, Takako; Zhang, Meili; Motoyama, Shiori; Maruyama, Nobuyuki; Utsumi, Shigeru

    2008-11-12

    Legume seeds contain 7S and/or 11S globulins as major storage proteins. The amino acid sequences of them from many legumes are similar to each other in the species but different from each other, meaning that some of these proteins from some crops exhibit excellent functional properties. To demonstrate this, we compared protein chemical and functional properties (thermal stability, surface hydrophobicity, solubility as a function of pH, and emulsifying properties) of these proteins from pea, fava bean, cowpea, and French bean with those of soybean as a control at the same conditions. The comparison clearly indicated that the 7S globulin of French bean exhibited excellent solubility (100%) at pH 4.2-7.0 even at a low ionic strength condition (mu = 0.08) and excellent emulsion stability (a little phase separation after 3 days) at pH 7.6 and mu = 0.08, although the emulsions from most of the other proteins separated in 1 h. These results indicate that our assumption is correct.

  5. Comparison of physicochemical properties of 7S and 11S globulins from pea, fava bean, cowpea, and French bean with those of soybean--French bean 7S globulin exhibits excellent properties.

    PubMed

    Kimura, Aiko; Fukuda, Takako; Zhang, Meili; Motoyama, Shiori; Maruyama, Nobuyuki; Utsumi, Shigeru

    2008-11-12

    Legume seeds contain 7S and/or 11S globulins as major storage proteins. The amino acid sequences of them from many legumes are similar to each other in the species but different from each other, meaning that some of these proteins from some crops exhibit excellent functional properties. To demonstrate this, we compared protein chemical and functional properties (thermal stability, surface hydrophobicity, solubility as a function of pH, and emulsifying properties) of these proteins from pea, fava bean, cowpea, and French bean with those of soybean as a control at the same conditions. The comparison clearly indicated that the 7S globulin of French bean exhibited excellent solubility (100%) at pH 4.2-7.0 even at a low ionic strength condition (mu = 0.08) and excellent emulsion stability (a little phase separation after 3 days) at pH 7.6 and mu = 0.08, although the emulsions from most of the other proteins separated in 1 h. These results indicate that our assumption is correct. PMID:18828597

  6. Regulation of the Aspergillus nidulans pectate lyase gene (pelA).

    PubMed Central

    Dean, R A; Timberlake, W E

    1989-01-01

    Aspergillus nidulans pectate lyase was purified from culture filtrates. The enzyme catalyzed a random eliminative cleavage reaction, had an apparent molecular weight of 40,000, and a pl of 4.2. Pectate lyase antisera were produced and used to identify pectate lyase clones in a cDNA expression library. Thirteen of 14 clones identified immunologically cross-hybridized. The identity of the single-copy pectate lyase gene, which we designated pelA, was confirmed in two ways. First, several cDNA clones expressed pectate lyase activity in Escherichia coli. Second, targeted mutation of the gene in A. nidulans resulted in complete loss of enzyme activity. pelA encodes a 1,300-nucleotide mRNA that was present in cells grown with polygalacturonic acid as carbon source but absent from cells grown with glucose or acetate as carbon source. Thus, pectate lyase expression is regulated at the level of mRNA accumulation. PMID:2535502

  7. Preparation of 4-arm star PELA and its encapsulation of rotavirus for drug delivery.

    PubMed

    Qingcong, Li; Xiaoxia, Pan; Hongli, Li; Minglong, Yuan

    2015-08-01

    A relatively high molecular weight of 4-arm star PELA was obtained by ring-opening polymerization of l-lactic acid O-carboxyanhydride with 4-arm-PEG in the presence of DMAP as an initiator. The results via(1)H NMR and (13)C NMR show that the end of the star PELA chain is a hydroxyl group and the central core is a PEG group. Rotavirus (strain SA11) was incorporated into 4-arm star PELA microspheres formulated by the water in oil in water emulsification solvent extraction method. The microspheres produced were spherical, and the mean diameter was 1.34 μm with a narrow size distribution. The drug release profile displayed a low burst release effect of 1.8% on the first day and a sustained release of antigen over 100 days. After the immunization of mice, the microsphere-entrapped RV elicited improved and long-lasting IgA and IgG antibody response in serum detected by ELISA in comparison to the free RV antigen. This study shows that 4-arm-PEG is an effective initiator for the ring-opening polymerization of Lac-OCA by DMAP as an initiator and that the resulting polymer is useful as a delivery system for the rotavirus vaccine.

  8. Effects of sequentially released BMP-2 and BMP-7 from PELA microcapsule-based scaffolds on the bone regeneration

    PubMed Central

    Li, Xialin; Yi, Weihong; Jin, Anmin; Duan, Yang; Min, Shaoxiong

    2015-01-01

    Osteoinductive biomaterials are helpful for the therapy of large bone defects and provide an alternative to autogenous bone and allografts. Recently, multiple growth factors are delivered to mimic the natural process of bone healing in the bone tissue engineering. Herein, we investigated the effects of sequential released bone morphogenetic protein-2 (BMP-2) and bone morphogenetic protein-7 (BMP-7) from polylactide-poly (ethylene glycol)-polylactide (PELA) microcapsule-based scaffolds on the bone regeneration. Through improving the double emulsion/solvent evaporation technique, BMP-7 was encapsulated in PELA microcapsules, to the surface of which BMP-2 was attached. Then, the scaffold (BMP-2/PELA/BMP-7) was fused by these microcapsules with dichloromethane vapor method. In vitro, it sequentially delivered bioactive BMP-2 and BMP-7 and partially imitated the profile of BMPs expression during the fracture healing. To determine the bioactivity of released BMP-2 and BMP-7, alkaline phosphatase (AKP) activity was analyzed in MC3T3-E1 cells. When compared with simple BMP-2 plus BMP-7group and pure PELA group, the AKP activity in BMP-2/PELA/BMP-7 group significantly increased. MTT assay indicated the BMP-loaded PELA scaffold had no adverse effects on cell activity. In addition, the effects of BMP-loaded scaffolds were also investigated in a rat femoral defect model by micro-computed tomographic (mCT) and histological examination. At 4 and 8 weeks post-implantation, BMP-2/PELA/BMP-7 significantly promoted osteogenesis as compared to other groups. The scaffold underwent gradual degradation and replacement by new bones at 8 weeks. Our findings suggest that the sequential release of BMP-2 and BMP-7from PELA microcapsule-based scaffolds is promising for the therapy of bone defects. PMID:26396672

  9. Clp and RpfF up-regulate transcription of pelA1 gene encoding the major pectate lyase in Xanthomonas campestris pv. campestris.

    PubMed

    Hsiao, Yi-Min; Fang, Mei-Chiung; Sun, Pei-Fang; Tseng, Yi-Hsiung

    2009-07-22

    Exopolysaccharide and several extracellular enzymes of Xanthomonas campestris pv. campestris (Xcc), the causative agent of black rot in crucifers, are virulence determinants. In this study, two Xcc annotated extracellular pectate lyase genes, pelA1 and pelA2, belonging to family 1 of the polysaccharide lyase, were characterized. Sequence and mutational analyses have demonstrated that pelA1 encodes the major pectate lyase, whereas pelA2 is not transcribed. Using the 5' RACE method, the pelA1 transcription initiation site was mapped at nucleotide G, 103 nt upstream of the pelA1 start codon. Promoter analysis demonstrated that polygalacturonic acid and CaCl(2) induce the expression of pelA1. Transcriptional fusion assays also indicated that Clp (cAMP receptor protein-like protein) and RpfF (an enoyl-CoA hydratase homologue that is required for the synthesis of cis-11-methyl-2-dodecenoic acid, a low molecular weight diffusible signal factor, DSF) positively regulate pelA1 transcription. Gel retardation assays showed that Clp exerts a positive control over expression of pelA1 by direct binding to the upstream Clp-binding site. In conclusion, the present research demonstrated that pelA1 codes for the major pectate lyase in Xcc strain Xc17 and that its expression is up-regulated by Clp and RpfF. This is the first study to characterize pectate lyase gene expression in Xcc.

  10. Genetic diversity and variability in populations of the white wax insect Ericerus pela, assessed by AFLP analysis.

    PubMed

    Chen, H; He, R; Wang, Z L; Wang, S Y; Chen, Y; Zhu, Z C; Chen, X M

    2015-12-22

    The white wax insect Ericerus pela Chavannes (Hemiptera: Coccoidea) is an economically valuable insect species that has been used for over a thousand years in China. The present study focuses on assessing the genetic variability in different populations of E. pela collected from seven Chinese provinces. The amplified fragment length polymorphism technique was used to generate DNA fingerprints of individuals from each population using nine primer combinations (EcoRI-MseI). A total of 435 polymorphic loci were generated; fragment sizes ranged from 200 to 1000 bp. The percentage of polymorphic loci was 85.29%. Nei's genetic diversity and Shannon index indicated consistency in the results, which showed that the Sichuan population had the highest diversity, followed by Yunnan and Zhejiang populations. Dendrogram analysis showed the shortest genetic distance between the Sichuan and Yunnan populations, suggesting that they probably form sister groups. High genetic differentiation between population values among all sampled populations indicated a low degree of genetic variability within each population (40.85%) and higher variation among populations (59.15%). Gene flow estimate values were low in all samples, suggesting low gene flow from events such as interbreeding and migration. Low gene flow values also suggested that populations among species of E. pela might become genetically heterogeneous, due to counteracting forces such as strong differential selection. Our data support the probability that E. pela will remain localized, and has a low potential to spread beyond current habitats.

  11. Experimental Pi.

    ERIC Educational Resources Information Center

    Corris, G.

    1990-01-01

    Discusses the calculation of pi by means of experimental methods. Polygon circle ratios, Archimedes' method, Buffon's needles, a Monte Carlo method, and prime number approaches are used. Presents three BASIC programs for the calculations. (YP)

  12. Convenience experimentation.

    PubMed

    Krohs, Ulrich

    2012-03-01

    Systems biology aims at explaining life processes by means of detailed models of molecular networks, mainly on the whole-cell scale. The whole cell perspective distinguishes the new field of systems biology from earlier approaches within molecular cell biology. The shift was made possible by the high throughput methods that were developed for gathering 'omic' (genomic, proteomic, etc.) data. These new techniques are made commercially available as semi-automatic analytic equipment, ready-made analytic kits and probe arrays. There is a whole industry of supplies for what may be called convenience experimentation. My paper inquires some epistemic consequences of strong reliance on convenience experimentation in systems biology. In times when experimentation was automated to a lesser degree, modeling and in part even experimentation could be understood fairly well as either being driven by hypotheses, and thus proceed by the testing of hypothesis, or as being performed in an exploratory mode, intended to sharpen concepts or initially vague phenomena. In systems biology, the situation is dramatically different. Data collection became so easy (though not cheap) that experimentation is, to a high degree, driven by convenience equipment, and model building is driven by the vast amount of data that is produced by convenience experimentation. This results in a shift in the mode of science. The paper shows that convenience driven science is not primarily hypothesis-testing, nor is it in an exploratory mode. It rather proceeds in a gathering mode. This shift demands another shift in the mode of evaluation, which now becomes an exploratory endeavor, in response to the superabundance of gathered data.

  13. Experimental errors?

    NASA Astrophysics Data System (ADS)

    Downie, Neil; Turner, Jez

    2014-07-01

    In reply to Matin Durrani's article “Experimental mistake” (May p15, see also http://ow.ly/vDYlM) criticizing plans to base A-level science exams in England entirely on written tests, with practical skills noted as a separate grade.

  14. Experimental colitis.

    PubMed

    MacPherson, B; Pfeiffer, C J

    1976-01-01

    Ulcerative colitis and Crohn's disease are complex, problematic diseases of unknown etiology in man, and appropriate experimental models would be useful in elucidating their pathogenesis and treatment. Although there have been numerous attempts to produce inflammatory ulcerative colonic disease in laboratory animals resembling those human disease forms, none has been entirely successful. Investigators have conducted experiments involving almost every etiological factor suggested for initiation of these diseases. The methods reviewed in this paper include production of experimental colitis by vascular impairment, and immunological methods such as bacterial infection, allergic reactions, direct and indirect hypersensitivity reactions, as well as autoimmune mechanisms. The results of carrageenan-induced colitis, irradiation, dietary, and drug-induced techniques are also discussed and the frequency and nature of spontaneous colonic lesions in animals is summarized.

  15. Animal experimentation.

    PubMed

    Kolar, Roman

    2006-01-01

    Millions of animals are used every year in often times extremely painful and distressing scientific procedures. Legislation of animal experimentation in modern societies is based on the supposition that this is ethically acceptable when certain more or less defined formal (e.g. logistical, technical) demands and ethical principles are met. The main parameters in this context correspond to the "3Rs" concept as defined by Russel and Burch in 1959, i.e. that all efforts to replace, reduce and refine experiments must be undertaken. The licensing of animal experiments normally requires an ethical evaluation process, often times undertaken by ethics committees. The serious problems in putting this idea into practice include inter alia unclear conditions and standards for ethical decisions, insufficient management of experiments undertaken for specific (e.g. regulatory) purposes, and conflicts of interest of ethics committees' members. There is an ongoing societal debate about ethical issues of animal use in science. Existing EU legislation on animal experimentation for cosmetics testing is an example of both the public will for setting clear limits to animal experiments and the need to further critically examine other fields and aspects of animal experimentation.

  16. Experimental macroevolution†

    PubMed Central

    Bell, Graham

    2016-01-01

    The convergence of several disparate research programmes raises the possibility that the long-term evolutionary processes of innovation and radiation may become amenable to laboratory experimentation. Ancestors might be resurrected directly from naturally stored propagules or tissues, or indirectly from the expression of ancestral genes in contemporary genomes. New kinds of organisms might be evolved through artificial selection of major developmental genes. Adaptive radiation can be studied by mimicking major ecological transitions in the laboratory. All of these possibilities are subject to severe quantitative and qualitative limitations. In some cases, however, laboratory experiments may be capable of illuminating the processes responsible for the evolution of new kinds of organisms. PMID:26763705

  17. Experimental macroevolution.

    PubMed

    Bell, Graham

    2016-01-13

    The convergence of several disparate research programmes raises the possibility that the long-term evolutionary processes of innovation and radiation may become amenable to laboratory experimentation. Ancestors might be resurrected directly from naturally stored propagules or tissues, or indirectly from the expression of ancestral genes in contemporary genomes. New kinds of organisms might be evolved through artificial selection of major developmental genes. Adaptive radiation can be studied by mimicking major ecological transitions in the laboratory. All of these possibilities are subject to severe quantitative and qualitative limitations. In some cases, however, laboratory experiments may be capable of illuminating the processes responsible for the evolution of new kinds of organisms. PMID:26763705

  18. Shape Memory Performance of Thermoplastic Amphiphilic Triblock Copolymer poly(D,L-lactic acid-co-ethylene glycol-co-D,L-lactic acid) (PELA)/Hydroxyapatite Composites

    PubMed Central

    Kutikov, Artem B.; Reyer, Kevin A.

    2015-01-01

    Biodegradable polymer/hydroxyapatite (HA) composites are desired for skeletal tissue engineering. When engineered with thermal-responsive shape memory properties, they may be delivered in a minimally invasive temporary shape and subsequently triggered to conform to a tissue defect. Here we report the shape memory properties of thermoplastic amphiphilic poly(D,L-lactic acid-co-ethylene glycol-co-D,L-lactic acid) (PELA, 120 kDa) and HA-PELA composites. These materials can be cold-deformed and stably fixed into temporary shapes at room temperature and undergo rapid shape recovery (< 3 s) at 50 °C. Stable fixation (>99% fixing ratio) of large deformations is achieved at −20 °C. While the shape recovery from tensile deformations slows with higher HA contents, all composites (up to 20 wt% HA) achieve high shape recovery (>90%) upon 10-min equilibration at 50 °C. The permanent shapes of HA-PELA can be reprogramed at 50 °C, and macroporous shape memory scaffolds can be fabricated by rapid prototyping. PMID:26457046

  19. EXPERIMENTAL THYROIDISM

    PubMed Central

    Cunningham, R. H.

    1898-01-01

    From the results of the various experiments already detailed I feel justified in drawing the following conclusions: (1) Absolutely fresh thyroid gland is not poisonous, in the usual sense of the term, when absorbed through the alimentary canal. (2) The symptoms of induced thyroidism are manifestations of an intoxication resulting from the ingestion of decomposed thyroid material, a conclusion that agrees in part with the previously related observations of Lanz. (3) The so-called experimental thyroidism is not specific for the thyroid only, for the ingestion of many substances derived from animal tissues other than the thyroid gland may produce an intoxication strikingly similar in every respect to that of experimental thyroidism. (4) Most, if not all, animal tissues yield substances which, if injected in large quantities directly into the circulation or beneath the skin, will produce an intoxication often very similar to that produced by injections of various substances derived from the fresh thyroid tissue. (5) The effects resulting from the intravascular or subcutaneous injections of aqueous extracts, decoctions and the concentrated extractives of the thyroid tissue, of the thymus, of muscle, etc., are by no means necessarily indicative of the function and the action of the hypothetical internal secretions of the same tissues during life. (6) The utilization of the fact that ingestion of decomposed thyroid material produces on certain occasions an intoxication with certain symptoms similar to some of those of G-raves' disease is not justifiable for the furtherance of the theory that the symptoms of exophthalmic goitre result from an over-production of the thyroid secretion. (7) Our results lead us to conclude with Drechsel that the fresh thyroid tissue yields at least probably two substances that are capable of palliating the symptoms of the acute cachexia in totally thyroidless dogs. (8) The thymus tissue also yields one and probably two substances that are as

  20. Experimental radioimmunotherapy.

    PubMed

    Buchsbaum, D J; Langmuir, V K; Wessels, B W

    1993-01-01

    Radiolabeled monoclonal antibodies have been used for radioimmunotherapy studies with human tumor spheroids and murine and human tumor xenografts in experimental animals. This paper reviews the work that has been performed in these models with different types of cancer, and highlights those papers that have presented dosimetry estimates and attempts to correlate the findings. Radioimmunotherapy studies in multicell spheroids, as a model for micrometastases, have been performed in human neuroblastoma, colon cancer, and melanoma cell lines using 131I-, 125I-, 186Re-, and 212Bi-labeled antibodies. The uniform geometry of the spheroid has allowed radiation dose estimates to be made. Up to three logs of cell kill have been achieved with 131I- and 186Re-specific antibody with minimal toxicity from labeled nonspecific antibody, but 212Bi-antibody had little effect because of its short half-life as shown by Langmuir. It appears that the two most important factors for therapeutic efficacy in this model are good penetration of the radiolabeled antibody and an adequate radionuclide half-life to allow penetration of the immunoconjugate prior to significant radionuclide decay. Radioimmunotherapy studies in animals bearing transplants of colon cancer, leukemia, lymphoma, hepatoma, renal cell carcinoma, neuroblastoma, glioma, mammary carcinoma, small cell lung carcinoma, cervical carcinoma, ovarian carcinoma, and bladder cancer have been performed with 131I, 90Y, 186Re, 153Sm, and 177Lu beta emitting, and 212Bi alpha emitting radionuclides conjugated to monoclonal antibodies. A few studies compared different radionuclides in the same model system. The approaches that have been used in these studies to estimate tumor dosimetry include the MIRD approach, thermoluminescent dosimetry, autoradiography, and comparison to external irradiation. The majority of investigators have estimated the dose to tumor and normal organs using MIRD-based calculations (time-activity curve and

  1. Sex differences in piercing-sucking sites on leaves of Ligustrum lucidum (Oleaceae) infested by the Chinese white wax scale insect, Ericerus pela (Chavannes) (Hemiptera: Coccidae).

    PubMed

    Zhao, J J; Wang, Z L; Chen, X M; Chen, Y

    2013-04-01

    The type of host tissues and cells ingested by piercing and sucking insects greatly affects their nutrient intake, which may subsequently affect insect fitness. This study describes the sex differences in feeding site selection between male and female nymphs of the Chinese white wax scale insect (CWWS), Ericerus pela (Chavannes), feeding on leaves of the Chinese privet, Ligustrum lucidum. Our data showed that the stylet tips of female nymphs terminated in the phloem sieve elements of main or lateral veins, while those of male nymphs terminated in the palisade parenchyma. We concluded that female nymphs fed from sieve elements and males fed from parenchyma cells. The potential impact of these feeding patterns was discussed in relation to the selection of a site for attachment, nutrient acquisition, and mouthpart stretching mechanism. Among these factors, selection of a site for attachment and mouthpart stretching mechanism may be the main cause of sex differences in feeding sites between female and male nymphs of CWWS. PMID:23949749

  2. Experimental Summary and Outlook

    SciTech Connect

    Peter Bosted

    2005-02-01

    A brief experimental overview of the workshop is given, with emphasis on polarized targets from the experimental equipment perspective, and kinematic coverage, precision, and newly investigated channels from the experimental results perspective.

  3. Microexperiencia Educativa (Microeducational Experimentation).

    ERIC Educational Resources Information Center

    Burton Meis, Roberto

    1970-01-01

    Experimentation for educational reform in Argentina is limited to specifically designated schools which are to be in a permanent state of experimentation. This article presents the official statements designating the experimental schools and includes remarks covering administration, evaluation, and supervision. (VM)

  4. The Experimental Hydrology Wiki

    NASA Astrophysics Data System (ADS)

    Blume, T.; Tromp-van Meerveld, I.

    2009-04-01

    The „Experimental Hydrology Wiki" is a forum for experimental hydrologists, which allows us to learn about, recommend, question and discuss methods and equipment of experimental hydrology. As a database of "lessons learned" it does not only contain short descriptions of specific experimental equipment but also information on encountered errors and problems and recommendations on how to deal with them. This makes valuable personal field experience accessible to a wider audience and thus helps us in not making the same mistakes others have made before us. The general idea and layout of the Experimental Hydrology Wiki is presented here along with an invitation to all experimental hydrologists to contribute with their knowledge and experience! http://www.experimental-hydrology.net/

  5. Is animal experimentation fundamental?

    PubMed

    d'Acampora, Armando José; Rossi, Lucas Félix; Ely, Jorge Bins; de Vasconcellos, Zulmar Acciolli

    2009-01-01

    The understanding about the utilization of experimental animals in scientific research and in teaching is many times a complex issue. Special attention needs to be paid to attain the understanding by the general public of the importance of animal experimentation in experimental research and in undergraduate medical teaching. Experimental teaching and research based on the availability of animals for experimentation is important and necessary for the personal and scientific development of the physician-to-be. The technological arsenal which intends to mimic experimentation animals and thus fully replace their use many times does not prove to be compatible with the reality of the living animal. The purpose of this paper is to discuss aspects concerning this topic, bringing up an issue which is complex and likely to arouse in-depth reflections.

  6. 7. VIEW WEST, FERNOW EXPERIMENTAL FOREST WELL HOUSE, FERNOW EXPERIMENTAL ...

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

    7. VIEW WEST, FERNOW EXPERIMENTAL FOREST WELL HOUSE, FERNOW EXPERIMENTAL FOREST BUNKHOUSE, FERNOW EXPERIMENTAL FOREST GARAGE, AND FERNOW EXPERIMENTAL FOREST RESIDENCE. - Parsons Nursery, South side of U.S. Route 219, Parsons, Tucker County, WV

  7. The Experimental Hydrology Wiki

    NASA Astrophysics Data System (ADS)

    Blume, Theresa; van Meerveld, Ilja; Graeff, Thomas

    2013-04-01

    The "Experimental Hydrology Wiki" is a forum for hydrologists to learn about, recommend, question and discuss new and established, basic and advanced methods and equipment for hydrological research. As a database of "lessons learned" it does not only contain short descriptions of specific experimental equipment but also information on encountered errors and problems and recommendations on how to deal with them. This makes valuable personal field experience accessible to a wider audience. The Wiki allows experimentalists to share and find solutions for common problems and thus helps us in not making the same mistakes others have made before us. At the same time modellers can use this platform to find information on sources of error and uncertainty in the data they use for model validation and calibration. The general idea and layout of the Experimental Hydrology Wiki is presented here along with an invitation to all experimental hydrologists to contribute their knowledge and experiences! http://www.experimental- hydrology.net/

  8. Experimental Semiotics: A Review

    PubMed Central

    Galantucci, Bruno; Garrod, Simon

    2010-01-01

    In the last few years a new line of research has appeared in the literature. This line of research, which may be referred to as experimental semiotics (ES; Galantucci, 2009; Galantucci and Garrod, 2010), focuses on the experimental investigation of novel forms of human communication. In this review we will (a) situate ES in its conceptual context, (b) illustrate the main varieties of studies thus far conducted by experimental semioticians, (c) illustrate three main themes of investigation which have emerged within this line of research, and (d) consider implications of this work for cognitive neuroscience. PMID:21369364

  9. Experimental semiotics: a review.

    PubMed

    Galantucci, Bruno; Garrod, Simon

    2011-01-01

    In the last few years a new line of research has appeared in the literature. This line of research, which may be referred to as experimental semiotics (ES; Galantucci, 2009; Galantucci and Garrod, 2010), focuses on the experimental investigation of novel forms of human communication. In this review we will (a) situate ES in its conceptual context, (b) illustrate the main varieties of studies thus far conducted by experimental semioticians, (c) illustrate three main themes of investigation which have emerged within this line of research, and (d) consider implications of this work for cognitive neuroscience.

  10. Designing an Experimental "Accident"

    ERIC Educational Resources Information Center

    Picker, Lester

    1974-01-01

    Describes an experimental "accident" that resulted in much student learning, seeks help in the identification of nematodes, and suggests biology teachers introduce similar accidents into their teaching to stimulate student interest. (PEB)

  11. Nuclear test experimental science

    SciTech Connect

    Struble, G.L.; Middleton, C.; Bucciarelli, G.; Carter, J.; Cherniak, J.; Donohue, M.L.; Kirvel, R.D.; MacGregor, P.; Reid, S.

    1989-01-01

    This report discusses research being conducted at Lawrence Livermore Laboratory under the following topics: prompt diagnostics; experimental modeling, design, and analysis; detector development; streak-camera data systems; weapons supporting research.

  12. Summary of experimental talks

    SciTech Connect

    Derrick, M.

    1999-12-08

    This final talk of the meeting briefly discussed a number of experimental topics that the author found particularly interesting in the area of High Energy Physics. It also includes some critical comments about the future direction of their discipline.

  13. Integrated Bayesian Experimental Design

    NASA Astrophysics Data System (ADS)

    Fischer, R.; Dreier, H.; Dinklage, A.; Kurzan, B.; Pasch, E.

    2005-11-01

    Any scientist planning experiments wants to optimize the design of a future experiment with respect to best performance within the scheduled experimental scenarios. Bayesian Experimental Design (BED) aims in finding optimal experimental settings based on an information theoretic utility function. Optimal design parameters are found by maximizing an expected utility function where the future data and the parameters of physical scenarios of interest are marginalized. The goal of the Integrated Bayesian Experimental Design (IBED) concept is to combine experiments as early as on the design phase to mutually exploit the benefits of the other experiments. The Bayesian Integrated Data Analysis (IDA) concept of linking interdependent measurements to provide a validated data base and to exploit synergetic effects will be used to design meta-diagnostics. An example is given by the Thomson scattering (TS) and the interferometry (IF) diagnostics individually, and a set of both. In finding the optimal experimental design for the meta-diagnostic, TS and IF, the strengths of both experiments can be combined to synergistically increase the reliability of results.

  14. Experimental scattershot boson sampling

    PubMed Central

    Bentivegna, Marco; Spagnolo, Nicolò; Vitelli, Chiara; Flamini, Fulvio; Viggianiello, Niko; Latmiral, Ludovico; Mataloni, Paolo; Brod, Daniel J.; Galvão, Ernesto F.; Crespi, Andrea; Ramponi, Roberta; Osellame, Roberto; Sciarrino, Fabio

    2015-01-01

    Boson sampling is a computational task strongly believed to be hard for classical computers, but efficiently solvable by orchestrated bosonic interference in a specialized quantum computer. Current experimental schemes, however, are still insufficient for a convincing demonstration of the advantage of quantum over classical computation. A new variation of this task, scattershot boson sampling, leads to an exponential increase in speed of the quantum device, using a larger number of photon sources based on parametric down-conversion. This is achieved by having multiple heralded single photons being sent, shot by shot, into different random input ports of the interferometer. We report the first scattershot boson sampling experiments, where six different photon-pair sources are coupled to integrated photonic circuits. We use recently proposed statistical tools to analyze our experimental data, providing strong evidence that our photonic quantum simulator works as expected. This approach represents an important leap toward a convincing experimental demonstration of the quantum computational supremacy. PMID:26601164

  15. Experimental scattershot boson sampling.

    PubMed

    Bentivegna, Marco; Spagnolo, Nicolò; Vitelli, Chiara; Flamini, Fulvio; Viggianiello, Niko; Latmiral, Ludovico; Mataloni, Paolo; Brod, Daniel J; Galvão, Ernesto F; Crespi, Andrea; Ramponi, Roberta; Osellame, Roberto; Sciarrino, Fabio

    2015-04-01

    Boson sampling is a computational task strongly believed to be hard for classical computers, but efficiently solvable by orchestrated bosonic interference in a specialized quantum computer. Current experimental schemes, however, are still insufficient for a convincing demonstration of the advantage of quantum over classical computation. A new variation of this task, scattershot boson sampling, leads to an exponential increase in speed of the quantum device, using a larger number of photon sources based on parametric down-conversion. This is achieved by having multiple heralded single photons being sent, shot by shot, into different random input ports of the interferometer. We report the first scattershot boson sampling experiments, where six different photon-pair sources are coupled to integrated photonic circuits. We use recently proposed statistical tools to analyze our experimental data, providing strong evidence that our photonic quantum simulator works as expected. This approach represents an important leap toward a convincing experimental demonstration of the quantum computational supremacy.

  16. SPHINX experimenters information package

    SciTech Connect

    Zarick, T.A.

    1996-08-01

    This information package was prepared for both new and experienced users of the SPHINX (Short Pulse High Intensity Nanosecond X-radiator) flash X-Ray facility. It was compiled to help facilitate experiment design and preparation for both the experimenter(s) and the SPHINX operational staff. The major areas covered include: Recording Systems Capabilities,Recording System Cable Plant, Physical Dimensions of SPHINX and the SPHINX Test cell, SPHINX Operating Parameters and Modes, Dose Rate Map, Experiment Safety Approval Form, and a Feedback Questionnaire. This package will be updated as the SPHINX facilities and capabilities are enhanced.

  17. Experimental probes of axions

    SciTech Connect

    Chou, Aaron S.; /Fermilab

    2009-10-01

    Experimental searches for axions or axion-like particles rely on semiclassical phenomena resulting from the postulated coupling of the axion to two photons. Sensitive probes of the extremely small coupling constant can be made by exploiting familiar, coherent electromagnetic laboratory techniques, including resonant enhancement of transitions using microwave and optical cavities, Bragg scattering, and coherent photon-axion oscillations. The axion beam may either be astrophysical in origin as in the case of dark matter axion searches and solar axion searches, or created in the laboratory from laser interactions with magnetic fields. This note is meant to be a sampling of recent experimental results.

  18. Experimentation: the next step

    PubMed Central

    Marinker, Marshall

    1987-01-01

    General practice has entered a period of accelerating change, and those responsible for planning its development now put forward a variety of promising proposals. Unless provision is made for large scale experimentation and scientific evaluation, the direction of future change will be determined not by evidence but by rhetoric. A framework for creating and evaluating a substantial programme of experimentation is suggested. The programme is the logical next step in the process of change which was given impetus by the publication of the government green paper. It should be seen as a professional, moral and political priority. PMID:3681850

  19. EXPERIMENTAL ANIMAL MAINTENANCE

    DOEpatents

    Finkel, M.P.

    1962-01-22

    A method of housing experimental animals such as mice in individual tube- like plastic enclosures is described. Contrary to experience, when this was tried with metal the mice did not become panicky. Group housing, with its attendant difficulties, may thus be dispensed with. (AEC)

  20. Communicating Uncertain Experimental Evidence

    ERIC Educational Resources Information Center

    Davis, Alexander L.; Fischhoff, Baruch

    2014-01-01

    Four experiments examined when laypeople attribute unexpected experimental outcomes to error, in foresight and in hindsight, along with their judgments of whether the data should be published. Participants read vignettes describing hypothetical experiments, along with the result of the initial observation, considered as either a possibility…

  1. Experimental Trends in Videoprogramming.

    ERIC Educational Resources Information Center

    Kalba, Kas

    A review of experimental activities in educational broadcasting shows that mass television and instructional television, as we think of them today, are likely to constitute two points on a greatly expanded spectrum of television concepts in the future. Television will become much more like the publishing industry, with its mix of pamphlets, art…

  2. Experimental fluvial geomorphology

    SciTech Connect

    Schumm, S.A.; Mosley, M.P.; Weaver, W.

    1987-01-01

    The authors bring together the results of several years of experimental work in drainage basin evolution, hydrology, river-channel morphology, and sedimentology. These investigations are related to real-world applications, particularly geological exploration and mapping. This text shows how awareness of natural phenomena can improve management of the natural environment, such as the control of rivers and eroding gullies.

  3. Administrative Aspects of Human Experimentation.

    ERIC Educational Resources Information Center

    Irvine, George W.

    1992-01-01

    The following administrative aspects of scientific experimentation with human subjects are discussed: the definition of human experimentation; the distinction between experimentation and treatment; investigator responsibility; documentation; the elements and principles of informed consent; and the administrator's role in establishing and…

  4. Teaching experimental design.

    PubMed

    Fry, Derek J

    2014-01-01

    Awareness of poor design and published concerns over study quality stimulated the development of courses on experimental design intended to improve matters. This article describes some of the thinking behind these courses and how the topics can be presented in a variety of formats. The premises are that education in experimental design should be undertaken with an awareness of educational principles, of how adults learn, and of the particular topics in the subject that need emphasis. For those using laboratory animals, it should include ethical considerations, particularly severity issues, and accommodate learners not confident with mathematics. Basic principles, explanation of fully randomized, randomized block, and factorial designs, and discussion of how to size an experiment form the minimum set of topics. A problem-solving approach can help develop the skills of deciding what are correct experimental units and suitable controls in different experimental scenarios, identifying when an experiment has not been properly randomized or blinded, and selecting the most efficient design for particular experimental situations. Content, pace, and presentation should suit the audience and time available, and variety both within a presentation and in ways of interacting with those being taught is likely to be effective. Details are given of a three-day course based on these ideas, which has been rated informative, educational, and enjoyable, and can form a postgraduate module. It has oral presentations reinforced by group exercises and discussions based on realistic problems, and computer exercises which include some analysis. Other case studies consider a half-day format and a module for animal technicians. PMID:25541547

  5. Teaching experimental design.

    PubMed

    Fry, Derek J

    2014-01-01

    Awareness of poor design and published concerns over study quality stimulated the development of courses on experimental design intended to improve matters. This article describes some of the thinking behind these courses and how the topics can be presented in a variety of formats. The premises are that education in experimental design should be undertaken with an awareness of educational principles, of how adults learn, and of the particular topics in the subject that need emphasis. For those using laboratory animals, it should include ethical considerations, particularly severity issues, and accommodate learners not confident with mathematics. Basic principles, explanation of fully randomized, randomized block, and factorial designs, and discussion of how to size an experiment form the minimum set of topics. A problem-solving approach can help develop the skills of deciding what are correct experimental units and suitable controls in different experimental scenarios, identifying when an experiment has not been properly randomized or blinded, and selecting the most efficient design for particular experimental situations. Content, pace, and presentation should suit the audience and time available, and variety both within a presentation and in ways of interacting with those being taught is likely to be effective. Details are given of a three-day course based on these ideas, which has been rated informative, educational, and enjoyable, and can form a postgraduate module. It has oral presentations reinforced by group exercises and discussions based on realistic problems, and computer exercises which include some analysis. Other case studies consider a half-day format and a module for animal technicians.

  6. Two Challenges for Experimenters

    NASA Astrophysics Data System (ADS)

    Berry, R. Stephen

    2013-10-01

    In recent years, several theoretical studies have indicated potentially interesting, even perhaps surprising phenomena that could be observed by experiment-but have not yet been studied in the laboratory. Here we give the background and motivation for two of these, with the admitted goal of stimulating those experimental studies. The two topics: (1) the production and study of amorphous alkali metal halide clusters; (2) Penning detachment, the analogue of the well-studied Penning ionization, but in which an electron is detached from a negative ion, rather than from a neutral atom, by energy transfer in collision with an excited atom. The latter phenomenon could be particularly relevant for stellar atmospheres where negative ions are abundant. In each case, we indicate the implications and potential of having substantive experimental information about each, in effect explaining the motivation to carry out the experiments.

  7. Geoengineering as Collective Experimentation.

    PubMed

    Stilgoe, Jack

    2016-06-01

    Geoengineering is defined as the 'deliberate and large-scale intervention in the Earth's climatic system with the aim of reducing global warming'. The technological proposals for doing this are highly speculative. Research is at an early stage, but there is a strong consensus that technologies would, if realisable, have profound and surprising ramifications. Geoengineering would seem to be an archetype of technology as social experiment, blurring lines that separate research from deployment and scientific knowledge from technological artefacts. Looking into the experimental systems of geoengineering, we can see the negotiation of what is known and unknown. The paper argues that, in renegotiating such systems, we can approach a new mode of governance-collective experimentation. This has important ramifications not just for how we imagine future geoengineering technologies, but also for how we govern geoengineering experiments currently under discussion.

  8. Geoengineering as Collective Experimentation.

    PubMed

    Stilgoe, Jack

    2016-06-01

    Geoengineering is defined as the 'deliberate and large-scale intervention in the Earth's climatic system with the aim of reducing global warming'. The technological proposals for doing this are highly speculative. Research is at an early stage, but there is a strong consensus that technologies would, if realisable, have profound and surprising ramifications. Geoengineering would seem to be an archetype of technology as social experiment, blurring lines that separate research from deployment and scientific knowledge from technological artefacts. Looking into the experimental systems of geoengineering, we can see the negotiation of what is known and unknown. The paper argues that, in renegotiating such systems, we can approach a new mode of governance-collective experimentation. This has important ramifications not just for how we imagine future geoengineering technologies, but also for how we govern geoengineering experiments currently under discussion. PMID:25862639

  9. Experimental adaptive Bayesian tomography

    NASA Astrophysics Data System (ADS)

    Kravtsov, K. S.; Straupe, S. S.; Radchenko, I. V.; Houlsby, N. M. T.; Huszár, F.; Kulik, S. P.

    2013-06-01

    We report an experimental realization of an adaptive quantum state tomography protocol. Our method takes advantage of a Bayesian approach to statistical inference and is naturally tailored for adaptive strategies. For pure states, we observe close to N-1 scaling of infidelity with overall number of registered events, while the best nonadaptive protocols allow for N-1/2 scaling only. Experiments are performed for polarization qubits, but the approach is readily adapted to any dimension.

  10. Experimental Neutrino Physics

    ScienceCinema

    Walter, Chris [Duke University, Durham, North Carolina, United States

    2016-07-12

    In this talk, I will review how a set of experiments in the last decade has given us our current understanding of neutrino properties.  I will show how experiments in the last year or two have clarified this picture, and will discuss how new experiments about to start will address remaining questions.  I will particularly emphasize the relationship between various experimental techniques.

  11. Blois V: Experimental summary

    SciTech Connect

    Albrow, M.G.

    1993-09-01

    The author gives a summary talk of the best experimental data given at the Vth Blois Workshop on Elastic and Diffractive Scattering. He addresses the following eight areas in his talk: total and elastic cross sections; single diffractive excitation; electron-proton scattering; di-jets and rapidity gaps; areas of future study; spins and asymmetries; high-transverse momentum and masses at the Tevatron; and disoriented chiral condensates and cosmic radiation.

  12. Experimental Models of Cryptococcosis

    PubMed Central

    Sabiiti, Wilber; May, Robin C.; Pursall, E. Rhiannon

    2012-01-01

    Cryptococcosis is a life-threatening fungal disease that infects around one million people each year. Establishment and progression of disease involves a complex interplay between the fungus and a diverse range of host cell types. Over recent years, numerous cellular, tissue, and animal models have been exploited to probe this host-pathogen interaction. Here we review the range of experimental models that are available for cryptococcosis research and compare the relative advantages and limitations of the different systems. PMID:22007224

  13. MSFC Skylab experimenter's reference

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The methods and techniques for experiment development and integration that evolved during the Skylab Program are described to facilitate transferring this experience to experimenters in future manned space programs. Management responsibilities and the sequential process of experiment evolution from initial concept through definition, development, integration, operation and postflight analysis are outlined in the main text and amplified, as appropriate, in appendixes. Emphasis is placed on specific lessons learned on Skylab that are worthy of consideration by future programs.

  14. EXPERIMENTAL ANIMAL WATERING DEVICE

    DOEpatents

    Finkel, M.P.

    1964-04-01

    A device for watering experimental animals confined in a battery of individual plastic enclosures is described. It consists of a rectangular plastic enclosure having a plurality of fluid-tight compartments, each with a drinking hole near the bottom and a filling hole on the top. The enclosure is immersed in water until filled, its drinking holes sealed with a strip of tape, and it is then placed in the battery. The tape sealing prevents the flow of water from the device, but permits animals to drink by licking the drinking holes. (AEC)

  15. Electrodeless Experimental Thruster

    SciTech Connect

    Brainerd, Jerome J.; Reisz, Al

    2009-03-16

    An electrodeless experimental electric thruster has been built and tested at the NASA Marshall Space Flight Center (MSFC). The plasma is formed by Electron-Cyclotron Resonance (ECR) absorption of RF waves (microwaves). The RF source operates in the 1 to 2 kW range. The plasma is overdense and is confined radially by an applied axial dc magnetic field. The field is shaped by a strong magnetic mirror on the upstream end and a magnetic nozzle on the downstream end. Argon is used as the propellant. The velocity profile in the exhaust plume has been measured with Laser Induced Fluorescence (LIF). An unusual bimodal velocity profile has been measured.

  16. Outsourcing of experimental work.

    PubMed

    Nielsen, Henrik

    2011-01-01

    With the development of new technologies for simultaneous analysis of many genes, transcripts, or proteins (the "omics" revolution), it has become common to outsource parts of the experimental work. In order to maintain the integrity of the research projects, it is important that the interphase between the researcher and the service is further developed. This involves robust protocols for sample preparation, an informed choice of analytical tool, development of standards for individual technologies, and transparent data analysis. This chapter introduces some of the problems related to analysis of RNA samples in the "omics" context and gives a few hints and key references related to sample preparation for the non-specialist.

  17. [Animal experimentation in Israel].

    PubMed

    Epstein, Yoram; Leshem, Micah

    2002-04-01

    In 1994 the Israeli parliament (Knesset) amended the Cruelty to Animals Act to regulate the use of experimental animals. Accordingly, animal experiments can only be carried out for the purposes of promoting health and medical science, reducing suffering, advancing scientific research, testing or production of materials and products (excluding cosmetics and cleaning products) and education. Animal experiments are only permitted if alternative methods are not possible. The National Board for Animal Experimentation was established to implement the law. Its members are drawn from government ministries, representatives of doctors, veterinarians, and industry organizations, animal rights groups, and academia. In order to carry out an animal experiment, the institution, researchers involved, and the specific experiment, all require approval by the Board. To date the Board has approved some 35 institutions, about half are public institutions (universities, hospitals and colleges) and the rest industrial firms in biotechnology and pharmaceutics. In 2000, 250,000 animals were used in research, 85% were rodents, 11% fowls, 1,000 other farm animals, 350 dogs and cats, and 39 monkeys. Academic institutions used 74% of the animals and industry the remainder. We also present summarized data on the use of animals in research in other countries.

  18. Experimental Quantum Coin Tossing

    NASA Astrophysics Data System (ADS)

    Molina-Terriza, G.; Vaziri, A.; Ursin, R.; Zeilinger, A.

    2005-01-01

    In this Letter we present the first implementation of a quantum coin-tossing protocol. This protocol belongs to a class of “two-party” cryptographic problems, where the communication partners distrust each other. As with a number of such two-party protocols, the best implementation of the quantum coin tossing requires qutrits, resulting in a higher security than using qubits. In this way, we have also performed the first complete quantum communication protocol with qutrits. In our experiment the two partners succeeded to remotely toss a row of coins using photons entangled in the orbital angular momentum. We also show the experimental bounds of a possible cheater and the ways of detecting him.

  19. Experimental traumatic brain injury

    PubMed Central

    2010-01-01

    Traumatic brain injury, a leading cause of death and disability, is a result of an outside force causing mechanical disruption of brain tissue and delayed pathogenic events which collectively exacerbate the injury. These pathogenic injury processes are poorly understood and accordingly no effective neuroprotective treatment is available so far. Experimental models are essential for further clarification of the highly complex pathology of traumatic brain injury towards the development of novel treatments. Among the rodent models of traumatic brain injury the most commonly used are the weight-drop, the fluid percussion, and the cortical contusion injury models. As the entire spectrum of events that might occur in traumatic brain injury cannot be covered by one single rodent model, the design and choice of a specific model represents a major challenge for neuroscientists. This review summarizes and evaluates the strengths and weaknesses of the currently available rodent models for traumatic brain injury. PMID:20707892

  20. Experimental evolution gone wild.

    PubMed

    Scheinin, M; Riebesell, U; Rynearson, T A; Lohbeck, K T; Collins, S

    2015-05-01

    Because of their large population sizes and rapid cell division rates, marine microbes have, or can generate, ample variation to fuel evolution over a few weeks or months, and subsequently have the potential to evolve in response to global change. Here we measure evolution in the marine diatom Skeletonema marinoi evolved in a natural plankton community in CO2-enriched mesocosms deployed in situ. Mesocosm enclosures are typically used to study how the species composition and biogeochemistry of marine communities respond to environmental shifts, but have not been used for experimental evolution to date. Using this approach, we detect a large evolutionary response to CO2 enrichment in a focal marine diatom, where population growth rate increased by 1.3-fold in high CO2-evolved lineages. This study opens an exciting new possibility of carrying out in situ evolution experiments to understand how marine microbial communities evolve in response to environmental change.

  1. [Experimental stab wound].

    PubMed

    Hirt, Miroslav; Vorel, František; Zelený, Michal

    2015-01-01

    Stab wounds caused by knives and daggers are usually of different appearances. The knife wound has one edge sharp while the second one is blunt. The wound caused by blow of dagger has both edges sharp. The forensic expert must very often decide whether the knife or dagger was used. The aim of this experimental work was to show how a single-edged knife penetrates the skin and causes the wound typical for the double-edged dagger. The fact was verified. The wound typical for dagger can be found if the knife is used only according to the scheme. The forensic expert can say that a one cutting edge knife was used if the one edge of wound is squared and the other one is sharp. If the both of them are sharp, forensic expert must be very careful in his decision.Key words: stab wounds - knife - dagger - forensic expertise. PMID:25671417

  2. Experimental Quantum Error Detection

    PubMed Central

    Jin, Xian-Min; Yi, Zhen-Huan; Yang, Bin; Zhou, Fei; Yang, Tao; Peng, Cheng-Zhi

    2012-01-01

    Faithful transmission of quantum information is a crucial ingredient in quantum communication networks. To overcome the unavoidable decoherence in a noisy channel, to date, many efforts have been made to transmit one state by consuming large numbers of time-synchronized ancilla states. However, such huge demands of quantum resources are hard to meet with current technology and this restricts practical applications. Here we experimentally demonstrate quantum error detection, an economical approach to reliably protecting a qubit against bit-flip errors. Arbitrary unknown polarization states of single photons and entangled photons are converted into time bins deterministically via a modified Franson interferometer. Noise arising in both 10 m and 0.8 km fiber, which induces associated errors on the reference frame of time bins, is filtered when photons are detected. The demonstrated resource efficiency and state independence make this protocol a promising candidate for implementing a real-world quantum communication network. PMID:22953047

  3. Experimental Economics in the Classroom.

    ERIC Educational Resources Information Center

    Walker, Joe

    1987-01-01

    Discusses and describes several studies regarding experimental economics. Recommends that economics teachers and textbook authors incorporate more of these projects into their work. Presents a consumer demand exercise that incorporates experimental economics into the classroom. (RKM)

  4. Antecedents and analogues - Experimental aircraft

    NASA Technical Reports Server (NTRS)

    Smith, R. H.

    1978-01-01

    The paper reviews the development of experimental aircraft from 1953 to the present. Consideration is given to the X-series experimental aircraft, to X-15 (the first aerospace plane), to the transition of experimental aircraft to high-speed flight, to XB-70 research, to lifting body research aircraft, and to current high-speed flight research.

  5. Experimental Particle Physics

    SciTech Connect

    Rosenfeld, Carl; Mishra, Sanjib R.; Petti, Roberto; Purohit, Milind V.

    2014-08-31

    The high energy physics group at the University of South Carolina, under the leadership of Profs. S.R. Mishra, R. Petti, M.V. Purohit, J.R. Wilson (co-PI's), and C. Rosenfeld (PI), engaged in studies in "Experimental Particle Physics." The group collaborated with similar groups at other universities and at national laboratories to conduct experimental studies of elementary particle properties. We utilized the particle accelerators at the Fermi National Accelerator Laboratory (Fermilab) in Illinois, the Stanford Linear Accelerator Center (SLAC) in California, and the European Center for Nuclear Research (CERN) in Switzerland. Mishra, Rosenfeld, and Petti worked predominantly on neutrino experiments. Experiments conducted in the last fifteen years that used cosmic rays and the core of the sun as a source of neutrinos showed conclusively that, contrary to the former conventional wisdom, the "flavor" of a neutrino is not immutable. A neutrino of flavor "e," "mu," or "tau," as determined from its provenance, may swap its identity with one of the other flavors -- in our jargon, they "oscillate." The oscillation phenomenon is extraordinarily difficult to study because neutrino interactions with our instruments are exceedingly rare -- they travel through the earth mostly unimpeded -- and because they must travel great distances before a substantial proportion have made the identity swap. Three of the experiments that we worked on, MINOS, NOvA, and LBNE utilize a beam of neutrinos from an accelerator at Fermilab to determine the parameters governing the oscillation. Two other experiments that we worked on, NOMAD and MIPP, provide measurements supportive of the oscillation experiments. Good measurements of the neutrino oscillation parameters may constitute a "low energy window" on related phenomena that are otherwise unobservable because they would occur only at energies way above the reach of conceivable accelerators. Purohit and Wilson participated in the BaBar experiment

  6. Experimental quantum data locking

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Cao, Zhu; Wu, Cheng; Fukuda, Daiji; You, Lixing; Zhong, Jiaqiang; Numata, Takayuki; Chen, Sijing; Zhang, Weijun; Shi, Sheng-Cai; Lu, Chao-Yang; Wang, Zhen; Ma, Xiongfeng; Fan, Jingyun; Zhang, Qiang; Pan, Jian-Wei

    2016-08-01

    Classical correlation can be locked via quantum means: quantum data locking. With a short secret key, one can lock an exponentially large amount of information in order to make it inaccessible to unauthorized users without the key. Quantum data locking presents a resource-efficient alternative to one-time pad encryption which requires a key no shorter than the message. We report experimental demonstrations of a quantum data locking scheme originally proposed by D. P. DiVincenzo et al. [Phys. Rev. Lett. 92, 067902 (2004), 10.1103/PhysRevLett.92.067902] and a loss-tolerant scheme developed by O. Fawzi et al. [J. ACM 60, 44 (2013), 10.1145/2518131]. We observe that the unlocked amount of information is larger than the key size in both experiments, exhibiting strong violation of the incremental proportionality property of classical information theory. As an application example, we show the successful transmission of a photo over a lossy channel with quantum data (un)locking and error correction.

  7. Experimental chloroquine retinopathy.

    PubMed

    Matsumura, M; Ohkuma, M; Tsukahara, I

    1986-01-01

    Chloroquine retinopathy was produced experimentally in the eye of the albino corydoras (one of the tropical fish) by daily administration of chloroquine (0.1 mg per os). The enucleated eyes were examined from the 14th day to 3 months after the beginning of drug administration under light and electron microscopy. The first change of retina was the appearance of membraneous cytoplasmic body (MCB) in the cytoplasm of ganglion, amacrine, bipolar and horizontal cells. MCB might be degenerated lysosome. They showed lamellar figures or crystalline lattice-like structures. Secondarily, these MCB appeared in the inner segments of photoreceptor cells. The outer segments of rod cells disappeared, and then those of cone cells. Although photoreceptor cells were diminished in number in advanced degeneration, the cells of inner nuclear layer and ganglion cells were maintained in number. The presence of MCB dose not mean death of cells. The retinal pigment epithelial cells contained MCB in its cytoplasm only in severe degenerative cases, and did not show other remarkable changes. MCB also appeared in the cytoplasm of pericytes of retinal vessels. Chloroquine is considered to damage directly photoreceptor cells most severely. PMID:3018650

  8. Thrombocytopenia in Experimental Trypanosomiasis

    PubMed Central

    Davis, Charles E.; Robbins, Robert S.; Weller, Richard D.; Braude, Abraham I.

    1974-01-01

    The effect of experimental trypanosomiasis on coagulation was studied because a patient in this hospital with Rhodesian trypanosomiasis developed thrombocytopenia with disseminated intravascular coagulation. Rats injected intraperitoneally with this strain of Trypanosoma rhodesiense consistently developed trypanosomiasis and severe thrombocytopenia without changes in hematocrit or concentration of fibrinogen or fibrin split products. At the time of 50% mortality (4-5 days) mean platelet counts per cubic millimeter of infected rats were 18,000±9,000 (±2 SEM) compared to 1,091,000±128,000 in uninfected controls. In vitro, concentrated trypanosomes and trypanosomefree supernates of disrupted organisms added to normal rat, rabbit, or human blood produced platelet aggregation within 30 min. This platelet aggregation was not blocked by inhibitors of ADP, kinins, or early or late components of complement. In vivo thrombocytopenia also occurred in infected rabbits congenitally deficient in C6 and in infected, splenectomized rats. Although the aggregating substance obtained from disrupted trypanosomes is heat-labile, it is active in the presence of complement inhibitors, suggesting that this trypanosomal product may be a protein enzyme or toxin. Since the phenomenon is independent of immune complexes, complement, ADP, and kinins, it appears to represent a new mechanism of microbial injury of platelets and the induction of thrombocytopenia. Images PMID:4207622

  9. Experimental optical diabolos.

    PubMed

    Egorov, Roman I; Soskin, Marat S; Freund, Isaac

    2006-07-01

    The canonical point singularity of elliptically polarized light is an isolated point of circular polarization, a C point. As one recedes from such a point the surrounding polarization figures evolve into ellipses characterized by a major axis of length a, a minor axis of length b, and an azimuthal orientational angle alpha: at the C point itself, alpha is singular (undefined) and a and b are degenerate. The profound effects of the singularity in alpha on the orientation of the ellipses surrounding the C point have been extensively studied both theoretically and experimentally for over two decades. The equally profound effects of the degeneracy of a and b on the evolving shapes of the surrounding ellipses have only been described theoretically. As one recedes from a C point, a and b generate a surface that locally takes the form of a double cone (i.e., a diabolo). Contour lines of constant a and b are the classic conic sections, ellipses or hyperbolas depending on the shape of the diabolo and its orientation relative to the direction of propagation. We present measured contour maps, surfaces, cones, and diabolos of a and b for a random ellipse field (speckle pattern).

  10. Particle physics---Experimental

    SciTech Connect

    Lord, J.J.; Boynton, P.E.; Burnett, T.H.; Wilkes, R.J.

    1991-08-21

    We are continuing a research program in particle astrophysics and high energy experimental particle physics. We have joined the DUMAND Collaboration, which is constructing a deep undersea astrophysical neutrino detector near Hawaii. Studies of high energy hadronic interactions using emulsion chamber techniques were also continued, using balloon flight exposures to ultra-high cosmic ray nuclei (JACEE) and accelerator beams. As members of the DUMAND Collaboration, we have responsibility for development a construction of critical components for the deep undersea neutrino detector facility. We have designed and developed the acoustical positioning system required to permit reconstruction of muon tracks with sufficient precision to meet the astrophysical goals of the experiment. In addition, we are making significant contributions to the design of the database and triggering system to be used. Work has been continuing in other aspects of the study of multiparticle production processes in nuclei. We are participants in a joint US/Japan program to study nuclear interactions at energies two orders of magnitude greater than those of existing accelerators, using balloon-borne emulsion chambers. On one of the flights we found two nuclear interactions of multiplicity over 1000 -- one with a multiplicity of over 2000 and pseudorapidity density {approximately} 800 in the central region. At the statistical level of the JACEE experiment, the frequency of occurrence of such events is orders of magnitude too large. We have continued our ongoing program to study hadronic interactions in emulsions exposed to high energy accelerator beams.

  11. X-38 Experimental Aerothermodynamics

    NASA Technical Reports Server (NTRS)

    Horvath, Thomas J.; Berry, Scott A.; Merski, N. Ronald; Fitzgerald, Steve M.

    2000-01-01

    The X-38 program seeks to demonstrate an autonomously returned orbital test flight vehicle to support the development of an operational Crew Return Vehicle for the International Space Station. The test flight, anticipated in 2002, is intended to demonstrate the entire mission profile of returning Space Station crew members safely back to earth in the event of medical or mechanical emergency. Integral to the formulation of the X-38 flight data book and the design of the thermal protection system, the aerothermodynamic environment is being defined through a synergistic combination of ground based testing and computational fluid dynamics. This report provides an overview of the hypersonic aerothermodynamic wind tunnel program conducted at the NASA Langley Research Center in support of the X-38 development. Global and discrete surface heat transfer force and moment, surface streamline patterns, and shock shapes were measured on scaled models of the proposed X-38 configuration in different test gases at Mach 6, 10 and 20. The test parametrics include angle of attack from 0 to 50 degs, unit Reynolds numbers from 0.3 x 10 (exp 6) to 16 x 10 (exp 6)/ ft, rudder deflections of 0, 2, and 5 deg. and body flap deflections from 0 to 30 deg. Results from hypersonic aerodynamic screening studies that were conducted as the configuration evolved to the present shape at, presented. Heavy gas simulation tests have indicated that the primary real gas effects on X-38 aerodynamics at trim conditions are expected to favorably influence flap effectiveness. Comparisons of the experimental heating and force and moment data to prediction and the current aerodynamic data book are highlighted. The effects of discrete roughness elements on boundary layer transition were investigated at Mach 6 and the development of a transition correlation for the X-38 vehicle is described. Extrapolation of ground based heating measurements to flight radiation equilibrium wall temperatures at Mach 6 and 10 were

  12. Experimental Volcanology: 2010 and 2020

    NASA Astrophysics Data System (ADS)

    Dingwell, D. B.

    2010-12-01

    The advent of an experimental approach to volcanology has its roots in decades-old laboratory based approaches to characterising the properties of magmas and analog materials, together with the attempts at simulating volcanic processes in the lab. A little over ten years ago many new thrusts of experimental advance led to a new dawn for experimental science applied to volcanic eruptions. Along with that, new expectations, new goals and new strategies emerged about ten years ago. Ten years later, in 2010, many fruits have been born of this labour, and new frontiers are being unfolded as we meet here. Here are some of the youngest captivating themes being explored in experimental programs today: 1) interfacing volcanic monitoring systems to experimentally generated eruptions. 2) elucidating the physicochemical behavior of experimentally generated volcanic ash as an agent in the earth system. 3) blending experimental rock deformation and magmatology studies to understand the strength and stability of volcanic materials and volcanic structures 4) exploiting the kinematics of experimentally-generated versus natural volcanic products to understand flow style and strain history. The past ten years of experimental developments in volcanology have prepared us for great advances in the future, most of which were not perceived as likely avenues of investigation as little as ten years ago! The situation is likely to repeat itself in 2020.

  13. Experimental Design and Some Threats to Experimental Validity: A Primer

    ERIC Educational Resources Information Center

    Skidmore, Susan

    2008-01-01

    Experimental designs are distinguished as the best method to respond to questions involving causality. The purpose of the present paper is to explicate the logic of experimental design and why it is so vital to questions that demand causal conclusions. In addition, types of internal and external validity threats are discussed. To emphasize the…

  14. [Broad beans (Vicia fava, L.) as an alternative source of protein in chick diets].

    PubMed

    Bezares, A; Cuca, M; Avila, E; Velásquez, C

    1980-03-01

    Three experiments were conducted to study the possibility of improving the nutritive value of broad beans (Vicia faba, L.) in poultry diets. In the first experiment, raw and autoclaved (1.0 kg/cm2/15 min) beans, with and without antibiotic supplementation, were studied. The results after 21 days showed no significant differences among treatments in regard to body weight. In feed conversion, however, a significant difference was observed when diets prepared with raw beans were supplemented with 20 ppm of flavomycin. In the second experiment raw and autoclaved beans were supplemented with 0, 10, and 20 ppm of virginiamycin and 200 and 400 ppm of flavomycin to study the effect of these two antibiotics. After 28 days, the results indicated no significant differences with antibiotic supplementation in either raw or autoclaved beans. However, a significant difference (P < 0.05) in body weight was found when beans were autoclaved. In the third experiment, two levels, 31 and 76% of raw and autoclaved beans, were included in the chick diets. The results in body weight, after 28 days, did not show any significant differences between raw and autoclaved beans fed at a 31% level. With the 76% level the autoclaved treatment, however, induced a significantly higher body weight than the diets containing raw beans. PMID:7447590

  15. Assessing Pupils' Skills in Experimentation

    ERIC Educational Resources Information Center

    Hammann, Marcus; Phan, Thi Thanh Hoi; Ehmer, Maike; Grimm, Tobias

    2008-01-01

    This study is concerned with different forms of assessment of pupils' skills in experimentation. The findings of three studies are reported. Study 1 investigates whether it is possible to develop reliable multiple-choice tests for the skills of forming hypotheses, designing experiments and analysing experimental data. Study 2 compares scores from…

  16. MEASUREMENT AND PRECISION, EXPERIMENTAL VERSION.

    ERIC Educational Resources Information Center

    Harvard Univ., Cambridge, MA. Harvard Project Physics.

    THIS DOCUMENT IS AN EXPERIMENTAL VERSION OF A PROGRAMED TEXT ON MEASUREMENT AND PRECISION. PART I CONTAINS 24 FRAMES DEALING WITH PRECISION AND SIGNIFICANT FIGURES ENCOUNTERED IN VARIOUS MATHEMATICAL COMPUTATIONS AND MEASUREMENTS. PART II BEGINS WITH A BRIEF SECTION ON EXPERIMENTAL DATA, COVERING SUCH POINTS AS (1) ESTABLISHING THE ZERO POINT, (2)…

  17. Majorana Thermosyphon Prototype Experimental Setup

    SciTech Connect

    Reid, Douglas J.; Guzman, Anthony D.; Munley, John T.

    2011-08-01

    This report presents the experimental setup of Pacific Northwest National Laboratory’s MAJORANA DEMONSTRATOR thermosyphon prototype cooling system. A nitrogen thermosyphon prototype of such a system has been built and tested at PNNL. This document presents the experimental setup of the prototype that successfully demonstrated the heat transfer performance of the system.

  18. Experimental Mathematics and Computational Statistics

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.

    2009-04-30

    The field of statistics has long been noted for techniques to detect patterns and regularities in numerical data. In this article we explore connections between statistics and the emerging field of 'experimental mathematics'. These includes both applications of experimental mathematics in statistics, as well as statistical methods applied to computational mathematics.

  19. Preclinical electrogastrography in experimental pigs

    PubMed Central

    Květina, Jaroslav; Varayil, Jithinraj Edakkanambeth; Ali, Shahzad Marghoob; Kuneš, Martin; Bureš, Jan; Tachecí, Ilja; Rejchrt, Stanislav; Kopáčová, Marcela

    2010-01-01

    Surface electrogastrography (EGG) is a non-invasive means of recording gastric myoelectric activity or slow waves from cutaneous leads placed over the stomach. This paper provides a comprehensive review of preclinical EGG. Our group recently set up and worked out the methods for EGG in experimental pigs. We gained our initial experience in the use of EGG in assessment of porcine gastric myoelectric activity after volume challenge and after intragastric administration of itopride and erythromycin. The mean dominant frequency in pigs is comparable with that found in humans. EGG in experimental pigs is feasible. Experimental EGG is an important basis for further preclinical projects in pharmacology and toxicology. PMID:21217873

  20. The Beginnings of Experimental Petrology

    ERIC Educational Resources Information Center

    Eugster, Hans P.

    1971-01-01

    An account of Van't Hoff's change from theoretical chemistry to petrology provides data on the European intellectual climate of the early 1900's and shows how his work laid the foundation for experimental petrology of hard rocks." (AL)

  1. Animal Experimentation in High Schools

    ERIC Educational Resources Information Center

    Ansevin, Kystyna D.

    1970-01-01

    Recommends that teacher and student be provided with the broadest possible spectrum of meaningful and feasible experiments in which the comfort of the experimental animal is protected by the design of the experiment. (BR)

  2. [Experimental studies of micromotor headpieces].

    PubMed

    Kanaev, V F; Repin, V A

    1982-01-01

    Experimental studies of handpieces for micromotors have been performed to make more precise their operating parameters. The special stand has been used for the measurements of the following data: head temperature, power losses in handpieces at no-load, and operating power required for machining by means of spherical burrs. The experimental results made it possible to specify more exactly the range of handpiece rotational speeds and to select optimum loads under reliability testing. PMID:7050601

  3. The experimental status of |Vub|

    NASA Astrophysics Data System (ADS)

    Won, Eunil

    2009-12-01

    In this presentation, we review the current experimental status in the measurements of |Vcb| from semileptonic B??? decays to DX ℓv???. Over 10 years of impressive progress in both theoretical and experimental approaches, now less than 2% precision is achieved. In order to further improve these measurements to test standard model, one expects to have better understanding of theoretical uncertainties and to have much more data from future higher luminosity B-factories and LHCb experiment.

  4. [The ethics of animal experimentation].

    PubMed

    Goffi, Jean-Yves

    2013-01-01

    The paper starts with a short definition of animal experimentation, then three main approaches to the practice are considered: unconditional approval (as advocated by Claude Bernard), conditional and restricted approval (as advocated by Peter Singer) and strict prohibition (as advocated by Tom Regan and Gary Francione). It is argued that what is actually approved or condemned in animal experimentation is the value of the scientific enterprise.

  5. Experimental Models for Neurotrauma Research.

    PubMed

    Davidsson, Johan; Risling, Mårten

    2016-01-01

    Physical trauma in the central nervous system (CNS) is usually the result of a number of forces in different directions and dimensions. A large number of experimental models have been developed to improve the possibilities to understand the outcome of CNS trauma. In this chapter, we will describe the need for a variety of experimental models for research on traumatic brain injury (TBI) and spinal cord injury (SCI). Models can serve different needs, such as: to test new treatments for injuries, to reveal thresholds for injuries, to provide a better understanding of injury mechanisms, or to test tools and methods for translation between experiments and clinical data. In this chapter, we will discuss on the validation of models and translation between experimental and clinical studies. PMID:27604724

  6. Experimental verification of quantum computation

    NASA Astrophysics Data System (ADS)

    Barz, Stefanie; Fitzsimons, Joseph F.; Kashefi, Elham; Walther, Philip

    2013-11-01

    Quantum computers are expected to offer substantial speed-ups over their classical counterparts and to solve problems intractable for classical computers. Beyond such practical significance, the concept of quantum computation opens up fundamental questions, among them the issue of whether quantum computations can be certified by entities that are inherently unable to compute the results themselves. Here we present the first experimental verification of quantum computation. We show, in theory and experiment, how a verifier with minimal quantum resources can test a significantly more powerful quantum computer. The new verification protocol introduced here uses the framework of blind quantum computing and is independent of the experimental quantum-computation platform used. In our scheme, the verifier is required only to generate single qubits and transmit them to the quantum computer. We experimentally demonstrate this protocol using four photonic qubits and show how the verifier can test the computer's ability to perform quantum computation.

  7. Experimentation on humans and nonhumans.

    PubMed

    Pluhar, Evelyn B

    2006-01-01

    In this article, I argue that it is wrong to conduct any experiment on a nonhuman which we would regard as immoral were it to be conducted on a human, because such experimentation violates the basic moral rights of sentient beings. After distinguishing the rights approach from the utilitarian approach, I delineate basic concepts. I then raise the classic "argument from marginal cases" against those who support experimentation on nonhumans but not on humans. After next replying to six important objections against that argument, I contend that moral agents are logically required to accord basic moral rights to every sentient being. I conclude by providing criteria for distinguishing ethical from unethical experimentation. PMID:16988895

  8. Animal experimentation ethics from an experimenter's point of view.

    PubMed

    Ehinger, B E

    1986-01-01

    The experimental biologist faces two kinds of ethical problems: practical and philosophical. The practical problems comprise increased costs of experimental animals, and the risk of being harassed or even raided by animal activists. There is also today a growing bureaucratic ethics overhead that has to be paid for, one way or another. The philosophical problems are the true ethical problems. Most laws and regulations emphasize that pain and agony should be minimized, but it is shown that this is neither always necessary nor always adequate. Scientists expect logical reasoning and opinions based on facts, but it is easy to find examples that the public opinion is quite illogical concerning pain and agony. For instance, you may under certain circumstances very well torture and kill animals just for pleasure. Our present legislation should be amended so as to concur better with current public views on how animals should be treated. The Swedish Committees on Animal Experimentation Ethics were intended to help scientists understand the demands of the public opinion. It is doubtful if they have been successful. The ethics of animal experimentation are perforce centered on the experimenter. He alone, at the final moment, makes the decision whether or not to use and, eventually, to kill the animal. When he kills, he obviously has a reason for doing so, and has decided that the purpose justifies the action. With the very large increase in the number of animal experiments in the last few decades, society has justifiably become increasingly concerned about the ethical considerations involved.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Experimental Approach to Teaching Fluids

    NASA Astrophysics Data System (ADS)

    Stern, Catalina

    2015-11-01

    For the last 15 years we have promoted experimental work even in the theoretical courses. Fluids appear in the Physics curriculum of the National University of Mexico in two courses: Collective Phenomena in their sophomore year and Continuum Mechanics in their senior year. In both, students are asked for a final project. Surprisingly, at least 85% choose an experimental subject even though this means working extra hours every week. Some of the experiments were shown in this congress two years ago. This time we present some new results and the methodology we use in the classroom. I acknowledge support from the Physics Department, Facultad de Ciencias, UNAM.

  10. Graphical Models for Quasi-Experimental Designs

    ERIC Educational Resources Information Center

    Kim, Yongnam; Steiner, Peter M.; Hall, Courtney E.; Su, Dan

    2016-01-01

    Experimental and quasi-experimental designs play a central role in estimating cause-effect relationships in education, psychology, and many other fields of the social and behavioral sciences. This paper presents and discusses the causal graphs of experimental and quasi-experimental designs. For quasi-experimental designs the authors demonstrate…

  11. Big Explosives Experimental Facility - BEEF

    SciTech Connect

    2014-10-31

    The Big Explosives Experimental Facility or BEEF is a ten acre fenced high explosive testing facility that provides data to support stockpile stewardship and other national security programs. At BEEF conventional high explosives experiments are safely conducted providing sophisticated diagnostics such as high speed optics and x-ray radiography.

  12. Experimental investigations of ICRF effects

    SciTech Connect

    Not Available

    1991-01-01

    The goal of the Phaedrus program is to establish the relative efficiency of helicity and momentum current drive for rf near and below omega{sub ci} and compare to theory. This paper discusses major accomplishments in the rf program; extension of operating parameters; facility improvements; and additional experimental activities. (LSP)

  13. Experimental medicine 1000 years ago

    PubMed Central

    Abdel-Halim, Rabie E.

    2011-01-01

    Little is known about the state of experimentation in the field of medicine during the Medieval Islamic era. With few exceptions, most of the contemporary sources on history of medicine propagate the idea that the roots of experimental medicine in its modern form, including clinical trials and drug-potency studies, first started during the European Renaissance in the 16th to the 18th centuries. This study is part of an ongoing multidisciplinary primary-source investigation of the original Arabic works of 11 Islamic medical scholars who lived and practiced between the 9th and the 13th centuries. The study critically evaluated and documented their contributions to the development of the scientific method and experimental medicine during that medieval Islamic era in several areas including critical appraisal of previous knowledge, clinical observations and case reports, clinical therapeutic trials, drug potency trials, experimentation on animals, dissection and dissection experiments as well as postmortem examinations. In each of the above-mentioned areas, significant contributions were made during the Medieval Islamic era from as early as the ninth century AD. PMID:21747591

  14. The drawing of experimental curves

    NASA Technical Reports Server (NTRS)

    Norton, F H

    1921-01-01

    This report presents a discussion of how to determine the location of a line or surface from experimental data. What we desire to know practically is the number of ordinates required to obtain a certain probable precision in drawing a line or surface.

  15. Experimental Neutrino Physics: Final Report

    SciTech Connect

    Lane, Charles E.; Maricic, Jelena

    2012-09-05

    Experimental studies of neutrino properties, with particular emphasis on neutrino oscillation, mass and mixing parameters. This research was pursued by means of underground detectors for reactor anti-neutrinos, measuring the flux and energy spectra of the neutrinos. More recent investigations have been aimed and developing detector technologies for a long-baseline neutrino experiment (LBNE) using a neutrino beam from Fermilab.

  16. Big Explosives Experimental Facility - BEEF

    ScienceCinema

    None

    2016-07-12

    The Big Explosives Experimental Facility or BEEF is a ten acre fenced high explosive testing facility that provides data to support stockpile stewardship and other national security programs. At BEEF conventional high explosives experiments are safely conducted providing sophisticated diagnostics such as high speed optics and x-ray radiography.

  17. Evaluating E-Labs' Experimentation

    ERIC Educational Resources Information Center

    Plaisent, Michel; Maguiraga, Lassana; Bernard, Prosper; Larhrib, Samir

    2004-01-01

    This communication discusses preliminary results on an experimentation of e-Learning with MIS students, mainly in order to cope with the logistics of lab organization. A learning management software was installed which changed completely the learning process, from content to logistics. Students have expressed their satisfaction with the e-Learning…

  18. An experimenter and his methodology

    NASA Astrophysics Data System (ADS)

    Filonovich, S. R.

    1990-12-01

    A review of experimental works by Ernst Mach has been given. The works reffer to optics and acoustics. The author is representing Ernst Mach as a physicist rather than a phylosopher, which contradicts the point of view obviously accepted in Soviet history of sciences and philosophy.

  19. Interpreting physicochemical experimental data sets.

    PubMed

    Colclough, Nicola; Wenlock, Mark C

    2015-09-01

    With the wealth of experimental physicochemical data available to chemoinformaticians from the literature, commercial, and company databases an increasing challenge is the interpretation of such datasets. Subtle differences in experimental methodology used to generate these datasets can give rise to variations in physicochemical property values. Such methodology nuances will be apparent to an expert experimentalist but not necessarily to the data analyst and modeller. This paper describes the differences between common methodologies for measuring the four most important physicochemical properties namely aqueous solubility, octan-1-ol/water distribution coefficient, pK(a) and plasma protein binding highlighting key factors that can lead to systematic differences. Insight is given into how to identify datasets suitable for combining. PMID:26054297

  20. Experimental multiparty sequential state discrimination

    NASA Astrophysics Data System (ADS)

    Solís-Prosser, M. A.; González, P.; Fuenzalida, J.; Gómez, S.; Xavier, G. B.; Delgado, A.; Lima, G.

    2016-10-01

    Recently, a protocol for quantum state discrimination (QSD) in a multiparty scenario has been introduced [Phys. Rev. Lett. 111, 100501 (2013), 10.1103/PhysRevLett.111.100501]. In this protocol, Alice generates a quantum system in one of two predefined nonorthogonal qubit states, and the goal is to send the generated state information to different parties without classical communication exchanged between them during the protocol's session. The interesting feature is that, by resorting to sequential generalized measurements onto this single system, there is a nonvanishing probability that all observers identify the state prepared by Alice. Here, we present the experimental implementation of this protocol based on polarization single-photon states. Our scheme works over an optical network, and since QSD lies in the core of many protocols, it represents a step towards experimental multiparty quantum information processing.

  1. Experimental research on air propellers

    NASA Technical Reports Server (NTRS)

    Durand, William F

    1918-01-01

    The purposes of the experimental investigation on the performance of air propellers described in this report are as follows: (1) the development of a series of design factors and coefficients drawn from model forms distributed with some regularity over the field of air-propeller design and intended to furnish a basis of check with similar work done in other aerodynamic laboratories, and as a point of departure for the further study of special or individual types and forms; (2) the establishment of a series of experimental values derived from models and intended for later use as a basis for comparison with similar results drawn from certain selected full-sized forms and tested in free flight.

  2. Experimental lithium system. Final report

    SciTech Connect

    Kolowith, R.; Berg, J.D.; Miller, W.C.

    1985-04-01

    A full-scale mockup of the Fusion Materials Irradiation Test (FMIT) Facility lithium system was built at the Hanford Engineering Development Laboratory (HEDL). This isothermal mockup, called the Experimental Lithium System (ELS), was prototypic of FMIT, excluding the accelerator and dump heat exchanger. This 3.8 m/sup 3/ lithium test loop achieved over 16,000 hours of safe and reliable operation. An extensive test program demonstrated satisfactory performance of the system components, including the HEDL-supplied electromagnetic lithium pump, the lithium jet target, the purification and characterization hardware, as well as the auxiliary argon and vacuum systems. Experience with the test loop provided important information on system operation, performance, and reliability. This report presents a complete overview of the entire Experimental Lithium System test program and also includes a summary of such areas as instrumentation, coolant chemistry, vapor/aerosol transport, and corrosion.

  3. Experimental unconditionally secure bit commitment.

    PubMed

    Liu, Yang; Cao, Yuan; Curty, Marcos; Liao, Sheng-Kai; Wang, Jian; Cui, Ke; Li, Yu-Huai; Lin, Ze-Hong; Sun, Qi-Chao; Li, Dong-Dong; Zhang, Hong-Fei; Zhao, Yong; Chen, Teng-Yun; Peng, Cheng-Zhi; Zhang, Qiang; Cabello, Adán; Pan, Jian-Wei

    2014-01-10

    Quantum physics allows for unconditionally secure communication between parties that trust each other. However, when the parties do not trust each other such as in the bit commitment scenario, quantum physics is not enough to guarantee security unless extra assumptions are made. Unconditionally secure bit commitment only becomes feasible when quantum physics is combined with relativistic causality constraints. Here we experimentally implement a quantum bit commitment protocol with relativistic constraints that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via free-space optical communication to two agents separated with more than 20 km. The security of the protocol relies on the properties of quantum information and relativity theory. In each run of the experiment, a bit is successfully committed with less than 5.68×10(-2) cheating probability. This demonstrates the experimental feasibility of quantum communication with relativistic constraints.

  4. Experimental Unconditionally Secure Bit Commitment

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Cao, Yuan; Curty, Marcos; Liao, Sheng-Kai; Wang, Jian; Cui, Ke; Li, Yu-Huai; Lin, Ze-Hong; Sun, Qi-Chao; Li, Dong-Dong; Zhang, Hong-Fei; Zhao, Yong; Chen, Teng-Yun; Peng, Cheng-Zhi; Zhang, Qiang; Cabello, Adán; Pan, Jian-Wei

    2014-01-01

    Quantum physics allows for unconditionally secure communication between parties that trust each other. However, when the parties do not trust each other such as in the bit commitment scenario, quantum physics is not enough to guarantee security unless extra assumptions are made. Unconditionally secure bit commitment only becomes feasible when quantum physics is combined with relativistic causality constraints. Here we experimentally implement a quantum bit commitment protocol with relativistic constraints that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via free-space optical communication to two agents separated with more than 20 km. The security of the protocol relies on the properties of quantum information and relativity theory. In each run of the experiment, a bit is successfully committed with less than 5.68×10-2 cheating probability. This demonstrates the experimental feasibility of quantum communication with relativistic constraints.

  5. Experimental unconditionally secure bit commitment

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Cao, Yuan; Curty, Marcos; Liao, Sheng-Kai; Wang, Jian; Cui, Ke; Li, Yu-Huai; Lin, Ze-Hong; Sun, Qi-Chao; Li, Dong-Dong; Zhang, Hong-Fei; Zhao, Yong; Chen, Teng-Yun; Peng, Cheng-Zhi; Zhang, Qiang; Cabello, Adan; Pan, Jian-Wei

    2014-03-01

    Quantum physics allows unconditionally secure communication between parties that trust each other. However, when they do not trust each other such as in the bit commitment, quantum physics is not enough to guarantee security. Only when relativistic causality constraints combined, the unconditional secure bit commitment becomes feasible. Here we experimentally implement a quantum bit commitment with relativistic constraints that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via free-space optical communication to two agents separated with more than 20 km. Bits are successfully committed with less than 5 . 68 ×10-2 cheating probability. This provides an experimental proof of unconditional secure bit commitment and demonstrates the feasibility of relativistic quantum communication.

  6. KRITZ-2 Experimental Benchmark Analysis

    SciTech Connect

    Pavlovichev, A.M.

    2001-09-28

    The KRITZ-2 experiment has been adopted by the OECD/NEA Task Force on Reactor-Based Plutonium Disposition for use as a benchmark exercise. The KRITZ-2 experiment consists of three different core configurations (one with near-weapons-grade MOX) with critical conditions a 20 C and 245 C. The KRITZ-2 experiment has calculated the MCU-REA code, which is a continuous energy Monte Carlo code system developed at the Russian Research Center--Kurchatov Institute and is used extensively in the Fissile Materials Disposition Program. The calculated results for k{sub eff} and fission rate distributions are compared with the experimental data and results of other codes. The results are in good agreement with the experimental values.

  7. Experimental unconditionally secure bit commitment.

    PubMed

    Liu, Yang; Cao, Yuan; Curty, Marcos; Liao, Sheng-Kai; Wang, Jian; Cui, Ke; Li, Yu-Huai; Lin, Ze-Hong; Sun, Qi-Chao; Li, Dong-Dong; Zhang, Hong-Fei; Zhao, Yong; Chen, Teng-Yun; Peng, Cheng-Zhi; Zhang, Qiang; Cabello, Adán; Pan, Jian-Wei

    2014-01-10

    Quantum physics allows for unconditionally secure communication between parties that trust each other. However, when the parties do not trust each other such as in the bit commitment scenario, quantum physics is not enough to guarantee security unless extra assumptions are made. Unconditionally secure bit commitment only becomes feasible when quantum physics is combined with relativistic causality constraints. Here we experimentally implement a quantum bit commitment protocol with relativistic constraints that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via free-space optical communication to two agents separated with more than 20 km. The security of the protocol relies on the properties of quantum information and relativity theory. In each run of the experiment, a bit is successfully committed with less than 5.68×10(-2) cheating probability. This demonstrates the experimental feasibility of quantum communication with relativistic constraints. PMID:24483878

  8. Does experimental research support psychoanalysis?

    PubMed

    Cohen, David

    2011-12-01

    The question of whether a psychodynamic view is compatible with experimental research is still a challenging issue-especially for child and adolescent psychopathology-despite the influence of psychoanalytic theory in this field until the 1980s. In this article, is explored the relationship between psychodynamic theory and experimental research using examples of evidence-based studies in the fields of (i) psychotherapeutic intervention assessment, (ii) placebo response in children and adolescents, (iii) unconscious lasting traumatic effects in children and adolescents, (iv) psychodynamic-oriented psychological testing. There are now a sufficient number of evidence-based studies to support the use of psychodynamic therapy in mental disorders, particularly in personality disorder and anxious/depressive disorder. In addition, placebo responses in children and adolescents with internalizing disorders are significantly higher in major depression compared to obsessive-compulsive disorder or other anxiety disorders, which highlights differential psychopathologies regarding the experience of loss. Also, using an experimental task, psychoanalysts are able to identify, without explicit knowledge and above the level of chance, healthy adults whose siblings had experienced cancer during childhood. This experiment suggests that implicit information regarding a participant's history is conveyed in interpersonal exchanges that can be intuitively perceived by judges experienced in listening to free associations from a psychodynamic perspective. Finally, psychodynamic-oriented psychological testing may predict the transition to schizophrenia in adolescents with a history of manic/mixed episodes. It can be concluded that there are no discrepancies between psychodynamic views and experimental data, whether one tests psychotherapeutic approaches, discusses data from other fields such as psychopharmacology, or designs experiments based on psychodynamic theory. PMID:21963530

  9. Elements of Bayesian experimental design

    SciTech Connect

    Sivia, D.S.

    1997-09-01

    We consider some elements of the Bayesian approach that are important for optimal experimental design. While the underlying principles used are very general, and are explained in detail in a recent tutorial text, they are applied here to the specific case of characterising the inferential value of different resolution peakshapes. This particular issue was considered earlier by Silver, Sivia and Pynn (1989, 1990a, 1990b), and the following presentation confirms and extends the conclusions of their analysis.

  10. Experimental tests of quantum chromodynamics

    SciTech Connect

    Dorfan, J.

    1987-04-01

    Experimental tests of quantum chromodynamics are discussed in the e/sup +/e/sup -/ continuum, in pp and anti p p collisions, in measurements of ..cap alpha../sub s/ from UPSILON decays, in deep inelastic lepton scattering, and in the measurement of the photon structure function. A large body of data relating to the testing of quantum chromodynamics is reviewed, showing qualitative agreement between the data from a wide range of processes and QCD. 66 refs., 79 figs. (LEW)

  11. Experimental observation of fractional echoes

    NASA Astrophysics Data System (ADS)

    Karras, G.; Hertz, E.; Billard, F.; Lavorel, B.; Siour, G.; Hartmann, J.-M.; Faucher, O.; Gershnabel, Erez; Prior, Yehiam; Averbukh, Ilya Sh.

    2016-09-01

    We report the observation of fractional echoes in a double-pulse excited nonlinear system. Unlike standard echoes, which appear periodically at delays which are integer multiples of the delay between the two exciting pulses, the fractional echoes appear at rational fractions of this delay. We discuss the mechanism leading to this phenomenon, and provide experimental demonstration of fractional echoes by measuring third harmonic generation in a thermal gas of CO2 molecules excited by a pair of femtosecond laser pulses.

  12. Experimental realization of invisibility cloaking

    NASA Astrophysics Data System (ADS)

    Shchelokova, A. V.; Melchakova, I. V.; Slobozhanyuk, A. P.; Yankovskaya, E. A.; Simovski, C. R.; Belov, P. A.

    2015-02-01

    Advances in the studies of metamaterials have pushed the development of invisibility cloaks, which suppress scattering by objects within certain frequency ranges. During recent years, there has been a transition from a purely theoretical consideration of the cloaking effect to its practical implementation. This paper is an overview of the current state of the art in the area of invisibility cloaks. Special emphasis is put on experimental realizations of such devices.

  13. Experimental data confronts nuclear structure

    SciTech Connect

    Garrett, J.D.

    1988-01-01

    The physical content of experimental data for a variety of excitation energies and angular momenta is summarized. The specific nuclear structure questions which these data address are considered. The specific regions discussed are: low-spin data near the particle separation thresholds; low-spin data at intermediate excitation energies; high-spin, near-yrast data and high-spin data at larger excitation energies. 63 refs., 14 figs., 1 tab.

  14. Experimental Crystallization of Yamato 980459

    NASA Technical Reports Server (NTRS)

    Jones, John H.; Galenas, M. G.; Danielson, L. R.

    2009-01-01

    Currently, only two martian meteorites QUE 94201 (QUE) and Yamato 980459 (Y98) have been experimentally shown to me true melt compositions. Most martian meteorites are instead, cumulates or partial cumulates. We have performed experiments on a Y98 composition to assess whether QUE could be related to Y98 by some fractionation process [1]. Y98 is a basaltic shergottite from the SNC (Shergotty, Nakhla, Chassigny) meteorite group. Y98 is composed of 26% olivine, 48% pyroxene, 25% mesostasis, and no plagioclase [2]. The large size of the olivine megacrysts and absence of plagioclase suggest that the parental melt which formed this meteorite had begun cooling slowly until some mechanism, such as magma ascent, caused rapid cooling [3]. Y98 s olivines have the highest Mg content of all the shergottites suggesting that it is the most primitive [4]. Y98 has been determined to be a melt composition by comparing the composition of experimental liquidus olivines with the composition of the cores of Y98 olivines [4]. The liquidus of Y98 is predicted by MELTS [5] and by experimentation [6] to be 1450 C. Analyses of Y98 show it to be very depleted in LREEs and it has similar depleted patterns as other shergottites such as QUE [7].

  15. National Ignition Facility: Experimental plan

    SciTech Connect

    Not Available

    1994-05-01

    As part of the Conceptual Design Report (CDR) for the National Ignition Facility (NIF), scientists from Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Sandia National Laboratory (SNL), the University of Rochester`s Laboratory for Laser Energetics (UR/LLE), and EG&G formed an NIF Target Diagnostics Working Group. The purpose of the Target Diagnostics Working Group is to prepare conceptual designs of target diagnostics for inclusion in the facility CDR and to determine how these specifications impact the CDR. To accomplish this, a subgroup has directed its efforts at constructing an approximate experimental plan for the ignition campaign of the NIF CDR. The results of this effort are contained in this document, the Experimental Plan for achieving fusion ignition in the NIF. This group initially concentrated on the flow-down requirements of the experimental campaign leading to ignition, which will dominate the initial efforts of the NIF. It is envisaged, however, that before ignition, there will be parallel campaigns supporting weapons physics, weapons effects, and other research. This plan was developed by analyzing the sequence of activities required to finally fire the laser at the level of power and precision necessary to achieve the conditions of an ignition hohlraum target, and to then use our experience in activating and running Nova experiments to estimate the rate of completing these activities.

  16. 47 CFR 73.1510 - Experimental authorizations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the degree required for the particular type of station. (3) The experimental operations may be... for the class and type of station must be met. AM stations also may conduct experimental operations... experimental transmissions. (d) The FCC may request a report of the research, experimentation and results...

  17. The philosophy of scientific experimentation: a review

    PubMed Central

    2009-01-01

    Practicing and studying automated experimentation may benefit from philosophical reflection on experimental science in general. This paper reviews the relevant literature and discusses central issues in the philosophy of scientific experimentation. The first two sections present brief accounts of the rise of experimental science and of its philosophical study. The next sections discuss three central issues of scientific experimentation: the scientific and philosophical significance of intervention and production, the relationship between experimental science and technology, and the interactions between experimental and theoretical work. The concluding section identifies three issues for further research: the role of computing and, more specifically, automating, in experimental research, the nature of experimentation in the social and human sciences, and the significance of normative, including ethical, problems in experimental science. PMID:20098589

  18. Watershed Allied Telemetry Experimental Research

    NASA Astrophysics Data System (ADS)

    Li, Xin; Li, Xiaowen; Li, Zengyuan; Ma, Mingguo; Wang, Jian; Xiao, Qing; Liu, Qiang; Che, Tao; Chen, Erxue; Yan, Guangjian; Hu, Zeyong; Zhang, Lixin; Chu, Rongzhong; Su, Peixi; Liu, Qinhuo; Liu, Shaomin; Wang, Jindi; Niu, Zheng; Chen, Yan; Jin, Rui; Wang, Weizhen; Ran, Youhua; Xin, Xiaozhou; Ren, Huazhong

    2009-11-01

    The Watershed Allied Telemetry Experimental Research (WATER) is a simultaneous airborne, satellite-borne, and ground-based remote sensing experiment aiming to improve the observability, understanding, and predictability of hydrological and related ecological processes at a catchment scale. WATER consists of the cold region, forest, and arid region hydrological experiments as well as a hydrometeorology experiment and took place in the Heihe River Basin, a typical inland river basin in the northwest of China. The field campaigns have been completed, with an intensive observation period lasting from 7 March to 12 April, from 15 May to 22 July, and from 23 August to 5 September 2008: in total, 120 days. Twenty-five airborne missions were flown. Airborne sensors including microwave radiometers at L, K, and Ka bands, imaging spectrometer, thermal imager, CCD, and lidar were used. Various satellite data were collected. Ground measurements were carried out at four scales, that is, key experimental area, foci experimental area, experiment site, and elementary sampling plot, using ground-based remote sensing instruments, densified network of automatic meteorological stations, flux towers, and hydrological stations. On the basis of these measurements, the remote sensing retrieval models and algorithms of water cycle variables are to be developed or improved, and a catchment-scale land/hydrological data assimilation system is being developed. This paper reviews the background, scientific objectives, experiment design, filed campaign implementation, and current status of WATER. The analysis of the data will continue over the next 2 years, and limited revisits to the field are anticipated.

  19. EXPERIMENTAL MODELLING OF AORTIC ANEURYSMS

    PubMed Central

    Doyle, Barry J; Corbett, Timothy J; Cloonan, Aidan J; O’Donnell, Michael R; Walsh, Michael T; Vorp, David A; McGloughlin, Timothy M

    2009-01-01

    A range of silicone rubbers were created based on existing commercially available materials. These silicones were designed to be visually different from one another and have distinct material properties, in particular, ultimate tensile strengths and tear strengths. In total, eleven silicone rubbers were manufactured, with the materials designed to have a range of increasing tensile strengths from approximately 2-4MPa, and increasing tear strengths from approximately 0.45-0.7N/mm. The variations in silicones were detected using a standard colour analysis technique. Calibration curves were then created relating colour intensity to individual material properties. All eleven materials were characterised and a 1st order Ogden strain energy function applied. Material coefficients were determined and examined for effectiveness. Six idealised abdominal aortic aneurysm models were also created using the two base materials of the study, with a further model created using a new mixing technique to create a rubber model with randomly assigned material properties. These models were then examined using videoextensometry and compared to numerical results. Colour analysis revealed a statistically significant linear relationship (p<0.0009) with both tensile strength and tear strength, allowing material strength to be determined using a non-destructive experimental technique. The effectiveness of this technique was assessed by comparing predicted material properties to experimentally measured methods, with good agreement in the results. Videoextensometry and numerical modelling revealed minor percentage differences, with all results achieving significance (p<0.0009). This study has successfully designed and developed a range of silicone rubbers that have unique colour intensities and material strengths. Strengths can be readily determined using a non-destructive analysis technique with proven effectiveness. These silicones may further aid towards an improved understanding of the

  20. Engine Combustion Network Experimental Data

    DOE Data Explorer

    Maintained by the Engine Combustion Department of Sandia National Laboratories, data currently available on the website includes reacting and non-reacting sprays in a constant-volume chamber at conditions typical of diesel combustion. The data are useful for model development and validation because of the well-defined boundary conditions and the wide range of conditions employed. A search utility displays data based on experimental conditions such as ambient temperature, ambient density, injection pressure, nozzle size, fuel, etc. Experiment-related visualizations are also available. (Specialized Interface)

  1. Thinnest optical waveguide: experimental test.

    PubMed

    Sumetsky, M; Dulashko, Y; Domachuk, P; Eggleton, B J

    2007-04-01

    A thin dielectric waveguide with a subwavelength diameter can exhibit very small transmission loss only if its diameter is greater than a threshold value, while for smaller diameters, waveguide loss grows dramatically. The threshold diameter of transition between these waveguiding and nonwaveguiding regimes is primarily determined by the wavelength of propagating light and, to a much lesser degree, by the characteristic length of the waveguide's long-range nonuniformity. For this reason, the transmission spectrum of a thin waveguide allows immediate and quite accurate determination of its thickness. An experimental test of these facts is performed for a tapered microfiber. Good agreement with the recently developed theory of adiabatic microfiber tapers is demonstrated.

  2. The updated experimental proteinoid model

    NASA Technical Reports Server (NTRS)

    Fox, S. W.; Nakashima, T.; Przybylski, A.; Syren, R. M.

    1982-01-01

    The experimental proteinoid model includes new results indicating that polymers sufficiently rich in basic amino acid catalyze the synthesis of peptides from ATP and amino acids and of oligonucleotides from ATP. The need for simulation syntheses of amino acids yielding significant proportions of basic amino acids is now in focus. The modeled simultaneous protocellular synthesis of peptides and polynucleotides is part of a more comprehensive proposal for the origin of the coded genetic mechanism. The finding of membrane and action potentials in proteinoid microspheres, with or without added lecithin, is reported. The crucial nature of a nonrandom matrix for protocells is developed.

  3. CDF experimental results on diffraction

    SciTech Connect

    Gallinaro, Michele; /Rockefeller U.

    2009-04-01

    Experimental results on diffraction from the Fermilab Tevatron collider obtained by the CDF experiment are reviewed and compared. We report on the diffractive structure function obtained from dijet production in the range 0 < Q{sup 2} < 10,000 GeV{sup 2}, and on the |t| distribution in the region 0 < |t| < 1 GeV{sup 2} for both soft and hard diffractive events up to Q{sup 2} {approx} 4,500 GeV{sup 2}. Results on single diffractive W/Z production, forward jets, and central exclusive production of both dijets and diphotons are also presented.

  4. Experimental test accelerator (ETA) II

    SciTech Connect

    Fessenden, T.J.; Atchison, W.L.; Birx, D.L.

    1981-03-06

    The Experimental Test Accelerator (ETA) is designed to produce a 10 kAmp electron beam at an energy of 4.5 MeV in 40 nsec pulses at an average rate of 2 pps. The accelerator also operates in bursts of 5 pulses spaced by as little as one millisec at an average rate of 5 pps. The machine is currently operating near 80% of its design values and has accumulated over 2.5 million pulses - mostly at a rate of one pps. The plasma cathode electron source, the remainder of the accelerator, and the operating characteristics of the machine are discussed.

  5. Experimental studies of glass refining

    NASA Technical Reports Server (NTRS)

    Subramanian, R. S.; Cole, R.; Kondos, P.

    1984-01-01

    The basic components of the experimental apparatus were selected and acquired. Techniques were developed for the fabrication of the special crucibles necessary for the experiments. Arrangements were made for the analysis of glass and gas bubble samples for composition information. Donations of major equipment were received for this project from Owens, Illinois where a similar study had been conducted a few year ago. Decisions were made regarding the actual glass composition to be used, the gas to be used in the first experiments, and the temperatures at which the experiments should be conducted. A microcomputer was acquired, and work was begun on interfacing the video analyzer to it.

  6. Experimental Parallel-Processing Computer

    NASA Technical Reports Server (NTRS)

    Mcgregor, J. W.; Salama, M. A.

    1986-01-01

    Master processor supervises slave processors, each with its own memory. Computer with parallel processing serves as inexpensive tool for experimentation with parallel mathematical algorithms. Speed enhancement obtained depends on both nature of problem and structure of algorithm used. In parallel-processing architecture, "bank select" and control signals determine which one, if any, of N slave processor memories accessible to master processor at any given moment. When so selected, slave memory operates as part of master computer memory. When not selected, slave memory operates independently of main memory. Slave processors communicate with each other via input/output bus.

  7. Experimental Plasma Research project summaries

    SciTech Connect

    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.

  8. Experimental study of vortex diffusers

    SciTech Connect

    Shakerin, S.; Miller, P.L.

    1995-11-01

    This report documents experimental research performed on vortex diffusers used in ventilation and air-conditioning systems. The main objectives of the research were (1) to study the flow characteristics of isothermal jets issuing from vortex diffusers, (2) to compare the vortex diffuser`s performance with that of a conventional diffuser, and (3) to prepare a report that disseminates the results to the designers of ventilation and air-conditioning systems. The researchers considered three diffusers: a conventional round ceiling diffuser and two different styles of vortex diffusers. Overall, the vortex diffusers create slightly more induction of ambient air in comparison to the conventional diffuser.

  9. A simple Cavendish experimental apparatus

    NASA Astrophysics Data System (ADS)

    Kossler, W. J.; Klein, Susann; Morrow, Dominick; Juliao, Andre

    2016-03-01

    A simple Cavendish apparatus is described that allows measurement of the gravitational constant G and makes observable the gravitational attraction between commonplace objects. The apparatus consists of a torsion balance constructed from readily available materials, including lead bricks and fishing weights ("sinkers"). A computer program is used to determine the gravitational field at the location of the small mass due to a nearby lead brick, which allows students to gain experience with numerical methods. Experimental results obtained are compatible with the accepted value of G.

  10. Experimental Modeling of Proliferative Vitreoretinopathy. An Experimental Morphological Study.

    PubMed

    Khoroshilova-Maslova, I P; Leparskaya, N L; Nabieva, M M; Andreeva, L D

    2015-05-01

    A model of proliferative vitreoretinopathy induced by simultaneous intravitreal injection of recombinant IL-1β and platelet concentrate is created and its main morphological manifestations are studied on Chinchilla rabbits. The model reflects pathogenesis of proliferative vitreoretinopathy: epiretinal membrane with the formation of retinal plication, traction detachment of the retina; moderate inflammatory reaction in the uveal tract, in the optic nerve infundibulum, in the vitreous body; intact structural elements of the retina, dissociation of the retinal pigmented epithelium cells with their subsequent migration. The model is adequate to the clinical picture of proliferative vitreoretinopathy in humans, which recommends it for experimental studies of the efficiency of drug therapy and prevention of this disease. PMID:26033599

  11. Experimental Anomalies in Neutrino Physics

    NASA Astrophysics Data System (ADS)

    Palamara, Ornella

    2014-03-01

    In recent years, experimental anomalies ranging in significance (2.8-3.8 σ) have been reported from a variety of experiments studying neutrinos over baselines less than 1 km. Results from the LSND and MiniBooNE short-baseline νe /νe appearance experiments show anomalies which cannot be described by oscillations between the three standard model neutrinos (the ``LSND anomaly''). In addition, a re-analysis of the anti-neutrino flux produced by nuclear power reactors has led to an apparent deficit in νe event rates in a number of reactor experiments (the ``reactor anomaly''). Similarly, calibration runs using 51Cr and 37Ar radioactive sources in the Gallium solar neutrino experiments GALLEX and SAGE have shown an unexplained deficit in the electron neutrino event rate over very short distances (the ``Gallium anomaly''). The puzzling results from these experiments, which together may suggest the existence of physics beyond the Standard Model and hint at exciting new physics, including the possibility of additional low-mass sterile neutrino states, have raised the interest in the community for new experimental efforts that could eventually solve this puzzle. Definitive evidence for sterile neutrinos would be a revolutionary discovery, with implications for particle physics as well as cosmology. Proposals to address these signals by employing accelerator, reactor and radioactive source experiments are in the planning stages or underway worldwide. In this talk some of these will be reviewed, with emphasis on the accelerator programs.

  12. Experimental evolution in biofilm populations

    PubMed Central

    Steenackers, Hans P.; Parijs, Ilse; Foster, Kevin R.; Vanderleyden, Jozef

    2016-01-01

    Biofilms are a major form of microbial life in which cells form dense surface associated communities that can persist for many generations. The long-life of biofilm communities means that they can be strongly shaped by evolutionary processes. Here, we review the experimental study of evolution in biofilm communities. We first provide an overview of the different experimental models used to study biofilm evolution and their associated advantages and disadvantages. We then illustrate the vast amount of diversification observed during biofilm evolution, and we discuss (i) potential ecological and evolutionary processes behind the observed diversification, (ii) recent insights into the genetics of adaptive diversification, (iii) the striking degree of parallelism between evolution experiments and real-life biofilms and (iv) potential consequences of diversification. In the second part, we discuss the insights provided by evolution experiments in how biofilm growth and structure can promote cooperative phenotypes. Overall, our analysis points to an important role of biofilm diversification and cooperation in bacterial survival and productivity. Deeper understanding of both processes is of key importance to design improved antimicrobial strategies and diagnostic techniques. PMID:26895713

  13. X-38 Experimental Controls Laws

    NASA Technical Reports Server (NTRS)

    Munday, Steve; Estes, Jay; Bordano, Aldo J.

    2000-01-01

    X-38 Experimental Control Laws X-38 is a NASA JSC/DFRC experimental flight test program developing a series of prototypes for an International Space Station (ISS) Crew Return Vehicle, often called an ISS "lifeboat." X- 38 Vehicle 132 Free Flight 3, currently scheduled for the end of this month, will be the first flight test of a modem FCS architecture called Multi-Application Control-Honeywell (MACH), originally developed by the Honeywell Technology Center. MACH wraps classical P&I outer attitude loops around a modem dynamic inversion attitude rate loop. The dynamic inversion process requires that the flight computer have an onboard aircraft model of expected vehicle dynamics based upon the aerodynamic database. Dynamic inversion is computationally intensive, so some timing modifications were made to implement MACH on the slower flight computers of the subsonic test vehicles. In addition to linear stability margin analyses and high fidelity 6-DOF simulation, hardware-in-the-loop testing is used to verify the implementation of MACH and its robustness to aerodynamic and environmental uncertainties and disturbances.

  14. Experimental evolution in biofilm populations.

    PubMed

    Steenackers, Hans P; Parijs, Ilse; Foster, Kevin R; Vanderleyden, Jozef

    2016-05-01

    Biofilms are a major form of microbial life in which cells form dense surface associated communities that can persist for many generations. The long-life of biofilm communities means that they can be strongly shaped by evolutionary processes. Here, we review the experimental study of evolution in biofilm communities. We first provide an overview of the different experimental models used to study biofilm evolution and their associated advantages and disadvantages. We then illustrate the vast amount of diversification observed during biofilm evolution, and we discuss (i) potential ecological and evolutionary processes behind the observed diversification, (ii) recent insights into the genetics of adaptive diversification, (iii) the striking degree of parallelism between evolution experiments and real-life biofilms and (iv) potential consequences of diversification. In the second part, we discuss the insights provided by evolution experiments in how biofilm growth and structure can promote cooperative phenotypes. Overall, our analysis points to an important role of biofilm diversification and cooperation in bacterial survival and productivity. Deeper understanding of both processes is of key importance to design improved antimicrobial strategies and diagnostic techniques. PMID:26895713

  15. Experimental signatures of quantum annealing

    NASA Astrophysics Data System (ADS)

    Boixo, Sergio

    2013-03-01

    Quantum annealing is a general strategy for solving optimization problems with the aid of quantum adiabatic evolution. How effective is rapid decoherence in precluding quantum effects in a quantum annealing experiment, and will engineered quantum annealing devices effectively perform classical thermalization when coupled to a decohering thermal environment? Using the D-Wave machine, we report experimental results for a simple problem which takes advantage of the fact that for quantum annealing the measurement statistics are determined by the energy spectrum along the quantum evolution, while in classical thermalization they are determined by the spectrum of the final Hamiltonian only. We establish an experimental signature which is consistent with quantum annealing, and at the same time inconsistent with classical thermalization, in spite of a decoherence timescale which is orders of magnitude shorter than the adiabatic evolution time. For larger and more difficult problems, we compare the measurements statistics of the D-Wave machine to large-scale numerical simulations of simulated annealing and simulated quantum annealing, implemented through classical and quantum Monte Carlo simulations. For our test cases the statistics of the machine are - within calibration uncertainties - indistinguishable from a simulated quantum annealer with suitably chosen parameters, but significantly different from a classical annealer. Work in collaboration with T. Albash, N. Chancellor, S. Isakov, D. Lidar, T. Roennow, F. Spedalieri, M. Troyer and Z. Wang.

  16. Experimental approach to neutron stars

    SciTech Connect

    Leifels, Yvonne

    2014-05-09

    The equation of state (EOS) of nuclear matter is of fundamental importance in many areas of nuclear physics and astrophysics In the laboratory, there are different means to study the nuclearmatter equation of state and its density dependence in particular: nuclear masses, neutron skins, pygmy resonance, and nuclear structure at the drip line give access to nuclear matter properties at densities lower than and at saturation density ρ0. Heavy ion reactions at energies above 0.1 AGeV are the only means to study nuclear matter at densities larger than normal nuclear matter density ρ0. In the beamenergy range of 0.1 to 2A GeV nuclear matter is compressed upto three times ρ0. Access to nuclear matter properties is achieved by simulating nuclear collisions by means of microscopic transport codes, or statistical or hydrodynamicalmodels. Characteristics of heavy-ion collisions are discussed, and experimental observables which allow to constrain nuclear matter properties by comparing experimental results with those of transport codes are presented. Special emphasis will be given to the density dependence of the symmetry energy which is the most relevant connection between neutron stars and heavy ion collisions.

  17. Animal husbandry and experimental design.

    PubMed

    Nevalainen, Timo

    2014-01-01

    If the scientist needs to contact the animal facility after any study to inquire about husbandry details, this represents a lost opportunity, which can ultimately interfere with the study results and their interpretation. There is a clear tendency for authors to describe methodological procedures down to the smallest detail, but at the same time to provide minimal information on animals and their husbandry. Controlling all major variables as far as possible is the key issue when establishing an experimental design. The other common mechanism affecting study results is a change in the variation. Factors causing bias or variation changes are also detectable within husbandry. Our lives and the lives of animals are governed by cycles: the seasons, the reproductive cycle, the weekend-working days, the cage change/room sanitation cycle, and the diurnal rhythm. Some of these may be attributable to routine husbandry, and the rest are cycles, which may be affected by husbandry procedures. Other issues to be considered are consequences of in-house transport, restrictions caused by caging, randomization of cage location, the physical environment inside the cage, the acoustic environment audible to animals, olfactory environment, materials in the cage, cage complexity, feeding regimens, kinship, and humans. Laboratory animal husbandry issues are an integral but underappreciated part of investigators' experimental design, which if ignored can cause major interference with the results. All researchers should familiarize themselves with the current routine animal care of the facility serving them, including their capabilities for the monitoring of biological and physicochemical environment.

  18. Experimental approach to neutron stars

    NASA Astrophysics Data System (ADS)

    Leifels, Yvonne

    2014-05-01

    The equation of state (EOS) of nuclear matter is of fundamental importance in many areas of nuclear physics and astrophysics In the laboratory, there are different means to study the nuclearmatter equation of state and its density dependence in particular: nuclear masses, neutron skins, pygmy resonance, and nuclear structure at the drip line give access to nuclear matter properties at densities lower than and at saturation density ρ0. Heavy ion reactions at energies above 0.1 AGeV are the only means to study nuclear matter at densities larger than normal nuclear matter density ρ0. In the beamenergy range of 0.1 to 2A GeV nuclear matter is compressed upto three times ρ0. Access to nuclear matter properties is achieved by simulating nuclear collisions by means of microscopic transport codes, or statistical or hydrodynamicalmodels. Characteristics of heavy-ion collisions are discussed, and experimental observables which allow to constrain nuclear matter properties by comparing experimental results with those of transport codes are presented. Special emphasis will be given to the density dependence of the symmetry energy which is the most relevant connection between neutron stars and heavy ion collisions.

  19. Experimental studies on pump limiters

    NASA Astrophysics Data System (ADS)

    Mioduszewski, P.

    1982-12-01

    Pump limiters are mechanical devices for He-ash removal, fuel particle control, and possibly impurity control. Different designs have been suggested by various authors over the past decade. However, the magnetic divertor concepts seemed to be more promising, mainly because of their remote plasma-material interactions. All of the characteristics of magnetic divertors have been proven experimentally, but the overall performance and complexity cause concern about their application to tokamak reactors. Consequently, it is now time to explore the potential of mechanical particle control devices, i.e. pump limiters. Because of the high recycling at the limiter, it is sufficient to exhaust only a small fraction, about 1-10%, of the limiter particle flux to remove e.g. He at its rate of production. Pump limiter experiments have been conducted so far on Alcator, PDX, Macrotor, and ISX. Depending on the experimental design, a pressure build-up of between 1 mTorr and 50 mTorr has been reported. The closed configuration pump limiters provide high collection efficiencies, but have to accomodate high power fluxes at the leading edge. An open configuration, on the other hand, avoids leading edges but provides only fairly low collection efficiencies. The pump limiter development program now calls for a full pump limiter to be implemented in a major tokamak device. Presently, full-size pump limiter experiments on PDX, ISX, and TEXTOR are in preparation.

  20. Experimental studies on pump limiters

    SciTech Connect

    Mioduszewski, P.

    1982-01-01

    Pump limiters are mechanical devices for He-ash removal, fuel particle control, and possibly impurity control. Different designs have been suggested by various authors over the past decade. However, the magnetic divertor concepts seemed to be more promising, mainly because of their remote plasma-material interactions. All of the characteristics of magnetic divertors have been proven experimentally, but the overall performance and complexity cause concern about their application to tokamak reactors. Consequently, it is time now to explore the potential of mechanical particle control devices, i.e. pump limiters. Because of the high recycling at the limiter, it is sufficient to exhaust only a small fraction, about 1 to 10%, of the limiter particle flux to remove e.g. He at its rate of production. Pump limiter experiments have been conducted so far on Alcator, PDX, Macrotor, and ISX. Depending on the experimental design, a pressure build-up of between 1 mTorr and 50 mTorr has been reported.

  1. Experimental evolution in biofilm populations.

    PubMed

    Steenackers, Hans P; Parijs, Ilse; Foster, Kevin R; Vanderleyden, Jozef

    2016-05-01

    Biofilms are a major form of microbial life in which cells form dense surface associated communities that can persist for many generations. The long-life of biofilm communities means that they can be strongly shaped by evolutionary processes. Here, we review the experimental study of evolution in biofilm communities. We first provide an overview of the different experimental models used to study biofilm evolution and their associated advantages and disadvantages. We then illustrate the vast amount of diversification observed during biofilm evolution, and we discuss (i) potential ecological and evolutionary processes behind the observed diversification, (ii) recent insights into the genetics of adaptive diversification, (iii) the striking degree of parallelism between evolution experiments and real-life biofilms and (iv) potential consequences of diversification. In the second part, we discuss the insights provided by evolution experiments in how biofilm growth and structure can promote cooperative phenotypes. Overall, our analysis points to an important role of biofilm diversification and cooperation in bacterial survival and productivity. Deeper understanding of both processes is of key importance to design improved antimicrobial strategies and diagnostic techniques.

  2. The beginnings of experimental petrology.

    PubMed

    Eugster, H P

    1971-08-01

    Van't Hoff's work constitutes the first systematic contribution to experimental petrology. At all times, the problem was perceived as geologic in nature and the laboratory results were checked against natural assemblages whenever possible. The phase rule was not used, nor, for that matter, was chemical thermodynamics, except for the Van't Hoff equation. However, the work of Van't Hoff and Van Deventer was indirectly involved in the evolution of phase theory by Roozeboom, Van Rijn van Alkemade, and Schreinemakers. Meyerhoffer himself wrote the first text explicitly devoted to the phase rule. The impact of Van't Hoff's study was enormous, but it was restricted to those geologists willing and able to cope with chemistry. Foremost among them were igneous petrologists who had long since accepted chemical arguments for classification purposes. I consider the Geophysical Laboratory program to be the most direct heir of the Van't Hoff approach. Although the shape of that program was formulated independently by Van Hise, Becker, Day, and others, the inspiration they derived from Van't Hoff's successes is clearly acknowledged. The study of the fusion of plagioclases by Day and Allen (41), which directly led to the authorization for the Geophysical Laboratory, was the igneous counterpart of Van't Hoff's low-temperature experimental petrology. On metamorphic petrology, too, Van't Hoff left his mark, with V. M. Goldschmidt acting as his disciple. The interpretation of the Kristiania contact rocks was explicitly based on Van't Hoff's double salt law in preference to the phase rule. Sedimentologists remained unaffected and continued their preoccupation with description and classification. Chemical arguments remained subordinate in their work and of an elementary nature, underscoring the chasm between "hard" rocks and "soft" rocks. This gulf is only now beginning to close as a result of the blossoming of experimental petrology and geochemistry since World War II. At last the

  3. Characterization of experimental equine glanders.

    PubMed

    Lopez, Jose; Copps, John; Wilhelmsen, Catherine; Moore, Richard; Kubay, Julie; St-Jacques, Marcel; Halayko, Stacey; Kranendonk, Christiaan; Toback, Shannon; DeShazer, David; Fritz, David L; Tom, Marina; Woods, Donald E

    2003-10-01

    Considerable advances in understanding of the disease caused by Burkholderia mallei have been made employing a combination of tools including genetic techniques and animal infection models. The development of small animal models has allowed us to assess the role of a number of putative virulence determinants in the pathogenesis of disease due to B. mallei. Due to the difficulties in performing active immunization studies in small animals, and due to the fact that the horse is the target mammalian species for glanders, we have initiated experimental studies on glanders in horses. Intratracheal deposition of B. mallei produced clinical glanders with organisms being recovered from tissues of infected horses. The model should prove to be of considerable value in our ongoing studies on the pathogenesis and vaccine development for glanders.

  4. ``Impulsar'': Experimental and Theoretical Investigations

    NASA Astrophysics Data System (ADS)

    Apollonov, V. V.

    2008-04-01

    The Objective of the "Impulsar" project is to accomplish a circle of experimental, engineering and technological works on creation of a high efficiency laser rocket engine. The project includes many organizations of the rocket industry and Academy of Sciences of Russia. High repetition rate pulse-periodic CO2 laser system project for launching will be presented. Optical system for 15 MW laser energy delivery and optical matrix of laser engine receiver will by discussed as well. Basic characteristics of the laser-based engine will be compared with theoretical predictions and important stages of further technology implementation (low frequency resonance). Relying on a wide cooperation of different branches of science and industry organizations it is very possible to use the accumulated potential for launching of nano-vehicles during the upcoming 4-5 years.

  5. Experimental activation of bound entanglement.

    PubMed

    Kaneda, Fumihiro; Shimizu, Ryosuke; Ishizaka, Satoshi; Mitsumori, Yasuyoshi; Kosaka, Hideo; Edamatsu, Keiichi

    2012-07-27

    Entanglement is one of the essential resources in quantum information and communication technology (QICT). The entanglement thus far explored and applied to QICT has been pure and distillable entanglement. Yet, there is another type of entanglement, called "bound entanglement," which is not distillable by local operations and classical communication. We demonstrate the experimental "activation" of the bound entanglement held in the four-qubit Smolin state, unleashing its immanent entanglement in distillable form, with the help of auxiliary two-qubit entanglement and local operations and classical communication. We anticipate that it opens the way to a new class of QICT applications that utilize more general classes of entanglement than ever, including bound entanglement.

  6. Experimental Internet Environment Software Development

    NASA Technical Reports Server (NTRS)

    Maddux, Gary A.

    1998-01-01

    Geographically distributed project teams need an Internet based collaborative work environment or "Intranet." The Virtual Research Center (VRC) is an experimental Intranet server that combines several services such as desktop conferencing, file archives, on-line publishing, and security. Using the World Wide Web (WWW) as a shared space paradigm, the Graphical User Interface (GUI) presents users with images of a lunar colony. Each project has a wing of the colony and each wing has a conference room, library, laboratory, and mail station. In FY95, the VRC development team proved the feasibility of this shared space concept by building a prototype using a Netscape commerce server and several public domain programs. Successful demonstrations of the prototype resulted in approval for a second phase. Phase 2, documented by this report, will produce a seamlessly integrated environment by introducing new technologies such as Java and Adobe Web Links to replace less efficient interface software.

  7. Sexually antagonistic genes: experimental evidence.

    PubMed

    Rice, W R

    1992-06-01

    When selection differs between the sexes, a mutation beneficial to one sex may be harmful to the other (sexually antagonistic). Because the sexes share a common gene pool, selection in one sex can interfere with the other's adaptive evolution. Theory predicts that sexually antagonistic mutations should accumulate in tight linkage with a new sex-determining gene, even when the harm to benefit ratio is high. Genetic markers and artificial selection were used to make a pair of autosomal genes segregate like a new pair of sex-determining genes in a Drosophila melanogaster model system. A 29-generation study provides experimental evidence that sexually antagonistic genes may be common in nature and will accumulate in response to a new sex-determining gene. PMID:1604317

  8. Collider Physics an Experimental Introduction

    NASA Astrophysics Data System (ADS)

    Elvezio Pagliarone, Carmine

    2011-04-01

    This paper reviews shortly a small part of the contents of a set of lectures, presented at the XIV International School of Particles and Fields in Morelia, state of Michoacán, Mexico, during November 2010. The main goal of those lectures was to introduce students to some of the basic ideas and tools required for experimental and phenomenological analysis of collider data. In particular, after an introduction to the scientific motivations, that drives the construction of powerful accelerator complexes, and the need of reaching high center of mass energies and luminosities, some basic concept about collider particle detectors will be discussed. A status about the present running colliders and collider experiments as well as future plans and research and development is also given.

  9. Extinction times in experimental populations.

    PubMed

    Drake, John M

    2006-09-01

    Predicting population extinctions is a key element of quantitative conservation biology and population ecology. Although stochastic population theories have long been used to obtain theoretical distributions of population extinction times, model-based predictions have rarely been tested. Here I report results from a quantitative analysis of extinction time in 281 experimental populations of water fleas (Daphnia magna) in variable environments. To my knowledge, this is the first quantitative estimate of the shape of the distribution of population extinction times based on extinction data for any species. The finding that the distribution of population extinction times was extraordinarily peaked is consistent with theoretical predictions for density-independent populations, but inconsistent with predictions for density-dependent populations. The tail of the extinction time distribution was not exponential. These results imply that our current theories of extinction are inadequate. Future work should focus on how demographic stochasticity scales with population size and effects of nonrandom variable environments on population growth and decline.

  10. α-Synuclein: Experimental Pathology.

    PubMed

    Hasegawa, Masato; Nonaka, Takashi; Masuda-Suzukake, Masami

    2016-01-01

    α-Synuclein, which is present as a small, soluble, cytosolic protein in healthy subjects, is converted to amyloid-like fibrils in diseases such as Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). Bulk synthesis of purified α-synuclein has made it more convenient to study the nature of the normal protein and the mechanism of its conversion to an abnormal form in vitro and in vivo. Synthetic α-synuclein fibrils and pathological α-synuclein from diseased brains can act as triggers to convert normal α-synuclein to an abnormal form via prion-like mechanisms. In this article, we describe the experimental pathologies of α-synuclein both in vitro and in vivo in human and animal models. Prion-like spreading of abnormal α-synuclein from cell to cell can account for the progression of these α-synucleinopathies. PMID:27481772

  11. Experimental subjects are not different

    PubMed Central

    Exadaktylos, Filippos; Espín, Antonio M.; Brañas-Garza, Pablo

    2013-01-01

    Experiments using economic games are becoming a major source for the study of human social behavior. These experiments are usually conducted with university students who voluntarily choose to participate. Across the natural and social sciences, there is some concern about how this “particular” subject pool may systematically produce biased results. Focusing on social preferences, this study employs data from a survey-experiment conducted with a representative sample of a city's population (N = 765). We report behavioral data from five experimental decisions in three canonical games: dictator, ultimatum and trust games. The dataset includes students and non-students as well as volunteers and non-volunteers. We separately examine the effects of being a student and being a volunteer on behavior, which allows a ceteris paribus comparison between self-selected students (students*volunteers) and the representative population. Our results suggest that self-selected students are an appropriate subject pool for the study of social behavior. PMID:23429162

  12. Experimental Gamma-Ray Astronomy

    NASA Astrophysics Data System (ADS)

    Paneque, David

    2012-07-01

    Our knowledge of the γ-ray sky has dramatically changed due to the advent of the new ground-based Imaging Atmospheric Cherenkov Telescopes (H.E.S.S., MAGIC and VEPJTAS) and the satellite-borne instruments (AGILE and Fermi). These facilities boosted the number of γ-ray sources by one order of magnitude in the last 6 years, providing us with about 2000 sources detected above 100 MeV (from space) and about 100 sources detected above 100 GeV (from the ground). The combination of this large leap in experimental capabilities together with the fact that the Universe is still quite unexplored at these extreme energies is evidence of a large scientific discovery potential that will surely make the decade 2010-2020 a golden age for γ-ray astronomy. In this manuscript I provide a subjective review of some of the most exciting observations from this rapidly evolving field during the last two years.

  13. 'Impulsar': Experimental and Theoretical Investigations

    SciTech Connect

    Apollonov, V. V.

    2008-04-28

    The Objective of the 'Impulsar' project is to accomplish a circle of experimental, engineering and technological works on creation of a high efficiency laser rocket engine. The project includes many organizations of the rocket industry and Academy of Sciences of Russia. High repetition rate pulse-periodic CO{sub 2} laser system project for launching will be presented. Optical system for 15 MW laser energy delivery and optical matrix of laser engine receiver will by discussed as well. Basic characteristics of the laser-based engine will be compared with theoretical predictions and important stages of further technology implementation (low frequency resonance). Relying on a wide cooperation of different branches of science and industry organizations it is very possible to use the accumulated potential for launching of nano-vehicles during the upcoming 4-5 years.

  14. Experimental computation with oscillatory integrals

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.

    2009-06-26

    A previous study by one of the present authors, together with D. Borwein and I. Leonard [8], studied the asymptotic behavior of the p-norm of the sinc function: sinc(x) = (sin x)/x and along the way looked at closed forms for integer values of p. In this study we address these integrals with the tools of experimental mathematics, namely by computing their numerical values to high precision, both as a challenge in itself, and also in an attempt to recognize the numerical values as closed-form constants. With this approach, we are able to reproduce several of the results of [8] and to find new results, both numeric and analytic, that go beyond the previous study.

  15. Interactive robots in experimental biology.

    PubMed

    Krause, Jens; Winfield, Alan F T; Deneubourg, Jean-Louis

    2011-07-01

    Interactive robots have the potential to revolutionise the study of social behaviour because they provide several methodological advances. In interactions with live animals, the behaviour of robots can be standardised, morphology and behaviour can be decoupled (so that different morphologies and behavioural strategies can be combined), behaviour can be manipulated in complex interaction sequences and models of behaviour can be embodied by the robot and thereby be tested. Furthermore, robots can be used as demonstrators in experiments on social learning. As we discuss here, the opportunities that robots create for new experimental approaches have far-reaching consequences for research in fields such as mate choice, cooperation, social learning, personality studies and collective behaviour.

  16. Experimental tomographic scanning (TOSCA) imagers

    NASA Astrophysics Data System (ADS)

    Hovland, H.

    2014-06-01

    The tomographic scanner (TOSCA) detects signals using line detectors scanning a scene at regularly distributed angles. These line scan signals are then processed to reconstruct 2-dimensional images. In the simplest form, a 1-axis rotating conical scan optics scans across a simple patterned reticle, the signal collection being done with a single pixel detector. Experimental mono- and multispectral cameras using this approach are demonstrated under varying illumination conditions. Of particular interest is the TOSCA system's ability to handle and compensate for light sources modulated with a frequency higher than that of the frame rate. We also demonstrate for the first time a TOSCA imager operating in the infrared region. The device is put together using 3D-printed key parts and low cost optical components, leading to a very economical infrared camera.

  17. An experimental superconducting helical undulator

    SciTech Connect

    Caspi, S.; Taylor, C.

    1995-12-31

    Improvements in the technology of superconducting magnets for high energy physics and recent advancements in SC materials with the artificial pinning centers (APC){sup 2}, have made a bifilar helical SC device an attractive candidate for a single-pass free electron laser (FEL){sup 3}. Initial studies have suggested that a 6.5 mm inner diameter helical device, with a 27 mm period, can generate a central field of 2-2.5 Tesla. Additional studies have also suggested that with a stored energy of 300 J/m, such a device can be made self-protecting in the event of a quench. However, since the most critical area associated with high current density SC magnets is connected with quenching and training, a short experimental device will have to be built and tested. In this paper we discuss technical issues relevant to the construction of such a device, including a conceptual design, fields, and forces.

  18. Experimental Tests of Special Relativity

    SciTech Connect

    Roberts, Tom

    2006-12-13

    Over the past century Special Relativity has become a cornerstone of modern physics, and its Lorentz invariance is a foundation of every current fundamental theory of physics. So it is crucial that it be thoroughly tested experimentally. The many tests of SR will be discussed, including several modern high-precision measurements. Several experiments that appear to be in conflict with SR will also be discussed, such as claims that the famous measurements of Michelson and Morley actually have a non-null result, and the similar but far more extensive measurements of Dayton Miller that 'determined the absolute motion of the earth'. But the errorbars for these old experiments are huge, and are larger than their purported signals. In short, SR has been tested extremely well and stands un-refuted today, but current thoughts about quantum gravity suggest that it might not truly be a symmetry of nature.

  19. Overview of Experimental Capabilities - Supersonics

    NASA Technical Reports Server (NTRS)

    Banks, Daniel W.

    2007-01-01

    This viewgraph presentation gives an overview of experimental capabilities applicable to the area of supersonic research. The contents include: 1) EC Objectives; 2) SUP.11: Elements; 3) NRA; 4) Advanced Flight Simulator Flexible Aircraft Simulation Studies; 5) Advanced Flight Simulator Flying Qualities Guideline Development for Flexible Supersonic Transport Aircraft; 6) Advanced Flight Simulator Rigid/Flex Flight Control; 7) Advanced Flight Simulator Rapid Sim Model Exchange; 8) Flight Test Capabilities Advanced In-Flight Infrared (IR) Thermography; 9) Flight Test Capabilities In-Flight Schlieren; 10) Flight Test Capabilities CLIP Flow Calibration; 11) Flight Test Capabilities PFTF Flowfield Survey; 12) Ground Test Capabilities Laser-Induced Thermal Acoustics (LITA); 13) Ground Test Capabilities Doppler Global Velocimetry (DGV); 14) Ground Test Capabilities Doppler Global Velocimetry (DGV); and 15) Ground Test Capabilities EDL Optical Measurement Capability (PIV) for Rigid/Flexible Decelerator Models.

  20. Summary: experimental gerontology in Austria.

    PubMed

    Wick, G

    2000-08-01

    Austria has a long and successful tradition in geriatric medicine, nursing and sociology. In contrast, research in experimental gerontology has only come into focus more recently. Gerontological research is performed in various laboratories and clinics of the Medical Schools of the Universities of Vienna, Graz and Innsbruck, respectively, as well as in the School of Veterinary Medicine in Vienna, the Institute for Applied Microbiology of the Vienna University for Agricultural Sciences, the Faculty of Natural Sciences of the University of Salzburg, and in extra-universitary institutions such as the Ludwig-Boltzmann-Institute for Aging Research in Vienna and the Institute for Biomedical Aging Research of the Austrian Academy of Sciences in Innsbruck. Therefore, the following brief reflections will be organized in a topographic fashion.

  1. Experimental quantum computing without entanglement.

    PubMed

    Lanyon, B P; Barbieri, M; Almeida, M P; White, A G

    2008-11-14

    Deterministic quantum computation with one pure qubit (DQC1) is an efficient model of computation that uses highly mixed states. Unlike pure-state models, its power is not derived from the generation of a large amount of entanglement. Instead it has been proposed that other nonclassical correlations are responsible for the computational speedup, and that these can be captured by the quantum discord. In this Letter we implement DQC1 in an all-optical architecture, and experimentally observe the generated correlations. We find no entanglement, but large amounts of quantum discord-except in three cases where an efficient classical simulation is always possible. Our results show that even fully separable, highly mixed, states can contain intrinsically quantum mechanical correlations and that these could offer a valuable resource for quantum information technologies.

  2. Experimental Tests of Special Relativity

    ScienceCinema

    Roberts, Tom [Illinois Institute of Technology, Chicago, Illinois, United States

    2016-07-12

    Over the past century Special Relativity has become a cornerstone of modern physics, and its Lorentz invariance is a foundation of every current fundamental theory of physics. So it is crucial that it be thoroughly tested experimentally. The many tests of SR will be discussed, including several modern high-precision measurements. Several experiments that appear to be in conflict with SR will also be discussed, such as claims that the famous measurements of Michelson and Morley actually have a non-null result, and the similar but far more extensive measurements of Dayton Miller that 'determined the absolute motion of the earth'. But the errorbars for these old experiments are huge, and are larger than their purported signals. In short, SR has been tested extremely well and stands un-refuted today, but current thoughts about quantum gravity suggest that it might not truly be a symmetry of nature.

  3. The UA9 experimental layout

    SciTech Connect

    Scandale, W.; Robert-Demolaize, G.; Arduini, G.; Assmann, R.; Bracco, C.; et al

    2011-10-13

    The UA9 experimental equipment was installed in the CERN-SPS in March '09 with the aim of investigating crystal assisted collimation in coasting mode. Its basic layout comprises silicon bent crystals acting as primary collimators mounted inside two vacuum vessels. A movable 60 cm long block of tungsten located downstream at about 90 degrees phase advance intercepts the deflected beam. Scintillators, Gas Electron Multiplier chambers and other beam loss monitors measure nuclear loss rates induced by the interaction of the beam halo in the crystal. Two Roman pots installed in the path of the deflected particles are equipped with a Medipix detector to reconstruct the transverse distribution of the impinging beam. Finally UA9 takes advantage of an LHC-collimator prototype installed close to the first Roman pot to help in setting the beam conditions and to analyze the efficiency to deflect the beam. This paper describes in details the hardware installed to study the crystal collimation during 2010.

  4. Experimental studies with palygorskite dusts.

    PubMed

    Wagner, J C; Griffiths, D M; Munday, D E

    1987-11-01

    As the preliminary results of experimental studies on dust from the palygorskite group have led to some confusion a detailed description of the completed investigation is given for clarification. As in other experiments the biological effects have been shown to be associated with the physical characteristics of the fibres in these specimens. Samples of sepiolite and attapulgite from Spain and a single sample of palygorskite from the United Kingdom have been studied. Serious abnormalities were produced only by the palygorskite and one of the attapulgite dusts. The palygorskite is of no commercial interest and the attapulgite was from one small deposit and was used only in the preparation of drilling mud in the exploration of oil deposits. PMID:2961365

  5. Communications satellites - The experimental years

    NASA Technical Reports Server (NTRS)

    Edelson, B. I.

    1983-01-01

    Only eight years after the launc of Sputnik-1 by the Soviet Union, the first commercial satellite, 'Early Bird', entered service. In just twelve years commercial satellite service extended around the earth and became profitable. The reasons for the successful development of the communications satellite services in a comparatively short time are considered. These reasons are related to the presence of three ingredients, taking into account technology to create the system, communications requirements to form a market, and a management structure to implement the system. The formation of the concept of using earth orbiting satellites for telecommunications is discussed. It is pointed out that the years from 1958 to 1964 were the true 'experimental years' for satellite communications. The rapid development of technology during this crucial period is described, giving attention to passive satellites, active systems, and development satellites.

  6. Ten Problems in Experimental Mathematics

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.; Kapoor, Vishaal; Weisstein, Eric

    2004-09-30

    This article was stimulated by the recent SIAM ''100 DigitChallenge'' of Nick Trefethen, beautifully described in a recent book. Indeed, these ten numeric challenge problems are also listed in a recent book by two of present authors, where they are followed by the ten symbolic/numeric challenge problems that are discussed in this article. Our intent was to present ten problems that are characteristic of the sorts of problems that commonly arise in ''experimental mathematics''. The challenge in each case is to obtain a high precision numeric evaluation of the quantity, and then, if possible, to obtain a symbolic answer, ideally one with proof. Our goal in this article is to provide solutions to these ten problems, and in the process present a concise account of how one combines symbolic and numeric computation, which may be termed ''hybrid computation'', in the process of mathematical discovery.

  7. Communications satellites - The experimental years

    NASA Astrophysics Data System (ADS)

    Edelson, B. I.

    1983-10-01

    Only eight years after the launc of Sputnik-1 by the Soviet Union, the first commercial satellite, 'Early Bird', entered service. In just twelve years commercial satellite service extended around the earth and became profitable. The reasons for the successful development of the communications satellite services in a comparatively short time are considered. These reasons are related to the presence of three ingredients, taking into account technology to create the system, communications requirements to form a market, and a management structure to implement the system. The formation of the concept of using earth orbiting satellites for telecommunications is discussed. It is pointed out that the years from 1958 to 1964 were the true 'experimental years' for satellite communications. The rapid development of technology during this crucial period is described, giving attention to passive satellites, active systems, and development satellites.

  8. VENUS-2 Experimental Benchmark Analysis

    SciTech Connect

    Pavlovichev, A.M.

    2001-09-28

    The VENUS critical facility is a zero power reactor located at SCK-CEN, Mol, Belgium, which for the VENUS-2 experiment utilized a mixed-oxide core with near-weapons-grade plutonium. In addition to the VENUS-2 Core, additional computational variants based on each type of fuel cycle VENUS-2 core (3.3 wt. % UO{sub 2}, 4.0 wt. % UO{sub 2}, and 2.0/2.7 wt.% MOX) were also calculated. The VENUS-2 critical configuration and cell variants have been calculated with MCU-REA, which is a continuous energy Monte Carlo code system developed at Russian Research Center ''Kurchatov Institute'' and is used extensively in the Fissile Materials Disposition Program. The calculations resulted in a k{sub eff} of 0.99652 {+-} 0.00025 and relative pin powers within 2% for UO{sub 2} pins and 3% for MOX pins of the experimental values.

  9. Experimental models of liver fibrosis

    PubMed Central

    Willebrords, Joost; Maes, Michaël; Colle, Isabelle; van den Bossche, Bert; de Oliveira, Claudia Pinto Marques Souza; Andraus, Wellington; Alves, Venâncio Avancini Ferreira; Leclercq, Isabelle; Vinken, Mathieu

    2015-01-01

    Hepatic fibrosis is a wound healing response to insults and as such affects the entire world population. In industrialized countries, the main causes of liver fibrosis include alcohol abuse, chronic hepatitis virus infection and non-alcoholic steatohepatitis. A central event in liver fibrosis is the activation of hepatic stellate cells, which is triggered by a plethora of signaling pathways. Liver fibrosis can progress into more severe stages, known as cirrhosis, when liver acini are substituted by nodules, and further to hepatocellular carcinoma. Considerable efforts are currently devoted to liver fibrosis research, not only with the goal of further elucidating the molecular mechanisms that drive this disease, but equally in view of establishing effective diagnostic and therapeutic strategies. The present paper provides a state-of-the-art overview of in vivo and in vitro models used in the field of experimental liver fibrosis research. PMID:26047667

  10. Microbial Communities as Experimental Units.

    PubMed

    Day, Mitch D; Beck, Daniel; Foster, James A

    2011-05-01

    Artificial ecosystem selection is an experimental technique that treats microbial communities as though they were discrete units by applying selection on community-level properties. Highly diverse microbial communities associated with humans and other organisms can have significant impacts on the health of the host. It is difficult to find correlations between microbial community composition and community-associated diseases, in part because it may be impossible to define a universal and robust species concept for microbes. Microbial communities are composed of potentially thousands of unique populations that evolved in intimate contact, so it is appropriate in many situations to view the community as the unit of analysis. This perspective is supported by recent discoveries using metagenomics and pangenomics. Artificial ecosystem selection experiments can be costly, but they bring the logical rigor of biological model systems to the emerging field of microbial community analysis.

  11. Experimental models of hepatocellular carcinoma☆

    PubMed Central

    Newell, Philippa; Villanueva, Augusto; Friedman, Scott L.; Koike, Kazuhiko; Llovet, Josep M.

    2010-01-01

    Hepatocellular carcinoma (HCC) is a common and deadly cancer whose pathogenesis is incompletely understood. Comparative genomic studies from human HCC samples have classified HCCs into different molecular subgroups; yet, the unifying feature of this tumor is its propensity to arise upon a background of inflammation and fibrosis. This review seeks to analyze the available experimental models in HCC research and to correlate data from human populations with them in order to consolidate our efforts to date, as it is increasingly clear that different models will be required to mimic different subclasses of the neoplasm. These models will be instrumental in the evaluation of compounds targeting specific molecular pathways in future preclinical studies. PMID:18314222

  12. Experimental subjects are not different.

    PubMed

    Exadaktylos, Filippos; Espín, Antonio M; Brañas-Garza, Pablo

    2013-01-01

    Experiments using economic games are becoming a major source for the study of human social behavior. These experiments are usually conducted with university students who voluntarily choose to participate. Across the natural and social sciences, there is some concern about how this "particular" subject pool may systematically produce biased results. Focusing on social preferences, this study employs data from a survey-experiment conducted with a representative sample of a city's population (N = 765). We report behavioral data from five experimental decisions in three canonical games: dictator, ultimatum and trust games. The dataset includes students and non-students as well as volunteers and non-volunteers. We separately examine the effects of being a student and being a volunteer on behavior, which allows a ceteris paribus comparison between self-selected students (students*volunteers) and the representative population. Our results suggest that self-selected students are an appropriate subject pool for the study of social behavior. PMID:23429162

  13. The ethics of animal experimentation.

    PubMed Central

    Lane-Petter, W.

    1976-01-01

    Animal experimentation arouses great emotion in many people, perhaps more especially in Britain, and this has increased as more sophisticated medical and non-medical animal experiments are demanded by modern research. The Cruelty to Animals Act of 1876 is the only legal regulation of experiments in animals, and many of its clauses are ambiguous. So in 1963 a committee of enquiry - the Littlewood Committee - was set up. Dr Lane-Petter examines the emotional and factual background to the enquiry, and discusses in an ethical context the usefulness and positive advantages of animal experiments compared with those of possible substitutes and in some detail three of the questions left unanswered by the Littlewood Committee. PMID:966259

  14. Compound chondrules: an experimental investigation

    NASA Astrophysics Data System (ADS)

    Connolly, H. C., Jr.; Hewins, R. H.; Atre, N.; Lofgren, G. E.

    1994-07-01

    Compound chondrules are considered to be the product of collisions between molten chondrules during chondrule formation Wasson, J. T. et al. (1994) have argued that some compound chondrules are formed when a chondrule with an accretional rim experienced a flash-melting event similar to a chondrule-forming event. We have designed experiments to investigate the formation of compound chondrules by both methods. Experiments were performed on a Deltech vertical muffle tube furnace to form synthetic chondrules to use as accretion rim material. For our experimental conditions, it is clear that compound chondrules can only be made by a collisional event. Our changes maintain their spherical shape and produce distinct boundaries between charges that are similar to natural compound chondrules. Furthermore, collision event(s) between chondrules will cause nucleation if they are molten and undercooled, thus producing chondrule textures. Flash melting chondrules with accretionary rims will not produce compound chondrules but will produce new chondrules with new textures.

  15. Remote experimental site concept development

    NASA Astrophysics Data System (ADS)

    Casper, Thomas A.; Meyer, William; Butner, David

    1995-01-01

    Scientific research is now often conducted on large and expensive experiments that utilize collaborative efforts on a national or international scale to explore physics and engineering issues. This is particularly true for the current US magnetic fusion energy program where collaboration on existing facilities has increased in importance and will form the basis for future efforts. As fusion energy research approaches reactor conditions, the trend is towards fewer large and expensive experimental facilities, leaving many major institutions without local experiments. Since the expertise of various groups is a valuable resource, it is important to integrate these teams into an overall scientific program. To sustain continued involvement in experiments, scientists are now often required to travel frequently, or to move their families, to the new large facilities. This problem is common to many other different fields of scientific research. The next-generation tokamaks, such as the Tokamak Physics Experiment (TPX) or the International Thermonuclear Experimental Reactor (ITER), will operate in steady-state or long pulse mode and produce fluxes of fusion reaction products sufficient to activate the surrounding structures. As a direct consequence, remote operation requiring robotics and video monitoring will become necessary, with only brief and limited access to the vessel area allowed. Even the on-site control room, data acquisition facilities, and work areas will be remotely located from the experiment, isolated by large biological barriers, and connected with fiber-optics. Current planning for the ITER experiment includes a network of control room facilities to be located in the countries of the four major international partners; USA, Russian Federation, Japan, and the European Community.

  16. Epithelial Ovarian Cancer Experimental Models

    PubMed Central

    Lengyel, E; Burdette, JE; Kenny, HA; Matei, D; Pilrose, J; Haluska, P.; Nephew, KP; Hales, DB; Stack, MS

    2014-01-01

    Epithelial ovarian cancer (OvCa) is associated with high mortality and, as the majority (>75%) of women with OvCa have metastatic disease at the time of diagnosis, rates of survival have not changed appreciably over 30 years. A mechanistic understanding of OvCa initiation and progression is hindered by the complexity of genetic and/or environmental initiating events and lack of clarity regarding the cell(s) or tissue(s) of origin. Metastasis of OvCa involves direct extension or exfoliation of cells and cellular aggregates into the peritoneal cavity, survival of matrix-detached cells in a complex ascites fluid phase, and subsequent adhesion to the mesothelium lining covering abdominal organs to establish secondary lesions containing host stromal and inflammatory components. Development of experimental models to recapitulate this unique mechanism of metastasis presents a remarkable scientific challenge and many approaches used to study other solid tumors (lung, colon, and breast, for example) are not transferable to OvCa research given the distinct metastasis pattern and unique tumor microenvironment. This review will discuss recent progress in the development and refinement of experimental models to study OvCa. Novel cellular, three-dimensional organotypic, and ex vivo models are considered and the current in vivo models summarized. The review critically evaluates currently available genetic mouse models of OvCa, the emergence of xenopatients, and the utility of the hen model to study OvCa prevention, tumorigenesis, metastasis, and chemoresistance. As these new approaches more accurately recapitulate the complex tumor microenvironment, it is predicted that new opportunities for enhanced understanding of disease progression, metastasis and therapeutic response will emerge. PMID:23934194

  17. Disposal phase experimental program plan

    SciTech Connect

    1997-01-31

    The Waste Isolation Pilot Plant (WIPP) facility comprises surface and subsurface facilities, including a repository mined in a bedded salt formation at a depth of 2,150 feet. It has been developed to safely and permanently isolate transuranic (TRU) radioactive wastes in a deep geological disposal site. On April 12, 1996, the DOE submitted a revised Resource Conservation and Recovery Act (RCRA) Part B permit application to the New Mexico Environment Department (NMED). The DOE anticipates receiving an operating permit from the NMED; this permit is required prior to the start of disposal operations. On October 29, 1996, the DOE submitted a Compliance Certification Application (CCA) to the US Environmental Protection Agency (EPA) in accordance with the WIPP land Withdrawal Act (LWA) of 1992 (Public Law 102-579) as amended, and the requirements of Title 40 of the Code of Federal Regulations (40 CFR) Parts 191 and 194. The DOE plans to begin disposal operations at the WIPP in November 1997 following receipt of certification by the EPA. The disposal phase is expected to last for 35 years, and will include recertification activities no less than once every five years. This Disposal Phase Experimental Program (DPEP) Plan outlines the experimental program to be conducted during the first 5-year recertification period. It also forms the basis for longer-term activities to be carried out throughout the 35-year disposal phase. Once the WIPP has been shown to be in compliance with regulatory requirements, the disposal phase gives an opportunity to affirm the compliance status of the WIPP, enhance the operations of the WIPP and the national TRU system, and contribute to the resolution of national and international nuclear waste management technical needs. The WIPP is the first facility of its kind in the world. As such, it provides a unique opportunity to advance the technical state of the art for permanent disposal of long-lived radioactive wastes.

  18. Experimental Constraints on Ureilite Petrogenesis

    NASA Technical Reports Server (NTRS)

    Singletary, Steven; Grove, Timothy L.

    2006-01-01

    This experimental study explores the petrogenesis of ureilites by a partial melting/smelting process. Experiments have been performed over temperature (1150-1280 C), pressure (5-12.5 MPa), and low oxygen fugacity (graphite-CO gas) conditions appropriate for a hypothetical ureilite parent body approximately 200 km in size. Experimental and modeling results indicate that a partial melting/smelting model of ureilite petrogenesis can explain many of the unique characteristics displayed by this meteorite group. Compositional information preserved in the pigeonite-olivine ureilites was used to estimate the composition of melts in equilibrium with the ureilites. The results of 20 experiments saturated with olivine, pyroxene, metal, and liquid with appropriate ureilite compositions are used to calibrate the phase coefficients and pressure-temperature dependence of the smelting reaction. The calibrated coefficients are used to model the behavior of a hypothetical residue that is experiencing fractional smelting. The residue is initially olivine-rich and smelting progressively depletes the olivine content and enriches the pyroxene and metal contents of the residues. The modeled residue composition at 1260 C best reproduces the trend of ureilite bulk compositions. The model results also indicate that as a ureilite residue undergoes isothermal decompression smelting over a range of temperatures, Ca/Al values and Cr203 contents are enriched at lower temperatures (below about 1240 C) and tend to decrease at higher temperatures. Therefore, fractional smelting can account for the high Ca/A1 and Cr203 wt% values observed in ureilites. We propose that ureilites were generated from an olivine-rich, cpx-bearing residue. Smelting began when the residue was partially melted and contained liquid, olivine, and carbon. These residues experienced varying degrees of fractional smelting to produce the compositional variability observed within the pigeonite-bearing ureilites. Variations in

  19. The 1986 Get Away Special Experimenter's Symposium

    NASA Technical Reports Server (NTRS)

    Thomas, Lawrence R. (Editor); Mosier, Frances L. (Editor)

    1987-01-01

    The 1986 Get Away Special (GAS) Experimenter's Symposium will provide a formal opportunity for GAS Experimenter's to share the results of their projects. The focus of this symposium is on payloads that will be flown in the future.

  20. Experimental "evolutional machines": mathematical and experimental modeling of biological evolution

    NASA Astrophysics Data System (ADS)

    Brilkov, A. V.; Loginov, I. A.; Morozova, E. V.; Shuvaev, A. N.; Pechurkin, N. S.

    Experimentalists possess model systems of two major types for study of evolution continuous cultivation in the chemostat and long-term development in closed laboratory microecosystems with several trophic structure If evolutionary changes or transfer from one steady state to another in the result of changing qualitative properties of the system take place in such systems the main characteristics of these evolution steps can be measured By now this has not been realized from the point of view of methodology though a lot of data on the work of both types of evolutionary machines has been collected In our experiments with long-term continuous cultivation we used the bacterial strains containing in plasmids the cloned genes of bioluminescence and green fluorescent protein which expression level can be easily changed and controlled In spite of the apparent kinetic diversity of evolutionary transfers in two types of systems the general mechanisms characterizing the increase of used energy flow by populations of primer producent can be revealed at their study According to the energy approach at spontaneous transfer from one steady state to another e g in the process of microevolution competition or selection heat dissipation characterizing the rate of entropy growth should increase rather then decrease or maintain steady as usually believed The results of our observations of experimental evolution require further development of thermodynamic theory of open and closed biological systems and further study of general mechanisms of biological

  1. Control design for the SERC experimental testbeds

    NASA Technical Reports Server (NTRS)

    Jacques, Robert; Blackwood, Gary; Macmartin, Douglas G.; How, Jonathan; Anderson, Eric

    1992-01-01

    Viewgraphs on control design for the Space Engineering Research Center experimental testbeds are presented. Topics covered include: SISO control design and results; sensor and actuator location; model identification; control design; experimental results; preliminary LAC experimental results; active vibration isolation problem statement; base flexibility coupling into isolation feedback loop; cantilever beam testbed; and closed loop results.

  2. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Experimental wine. 24.77... Experimental wine. (a) General. Any scientific university, college of learning, or institution of scientific research may, without payment of tax, produce, receive, blend, treat, and store wine for experimental...

  3. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Experimental wine. 24.77... Experimental wine. (a) General. Any scientific university, college of learning, or institution of scientific research may, without payment of tax, produce, receive, blend, treat, and store wine for experimental...

  4. 14 CFR 21.275 - Experimental certificates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Experimental certificates. 21.275 Section... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Delegation Option Authorization Procedures § 21.275 Experimental certificates. (a) The manufacturer shall, before issuing an experimental certificate, obtain from...

  5. 14 CFR 21.275 - Experimental certificates.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Experimental certificates. 21.275 Section... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Delegation Option Authorization Procedures § 21.275 Experimental certificates. (a) The manufacturer shall, before issuing an experimental certificate, obtain from...

  6. The '3Is' of animal experimentation.

    PubMed

    2012-05-29

    Animal experimentation in scientific research is a good thing: important, increasing and often irreplaceable. Careful experimental design and reporting are at least as important as attention to welfare in ensuring that the knowledge we gain justifies using live animals as experimental tools.

  7. Micas in experimentally shocked gneiss

    NASA Technical Reports Server (NTRS)

    Lambert, P.; Mackinnon, I. D. R.

    1984-01-01

    Powder-propellant guns are used to shock biotites and muscovites from a gneiss at pressures between 18 and 70 GPa. It is shown that shock in biotite and muscovite can produce homogeneous and devolatilized glasses within microseconds. Shock-deformed micas are found to exhibit fracturing, kinking, and complex extinction patterns over the entire pressure range investigated. Localized melting of micas commences at 33 GPa and reaches completion at 70 GPa. Even though melted biotite and muscovite are opaque optically, they exhibit extensive microvesiculation and flow when observed with the SEM. It is confirmed through electron diffraction that biotite and muscovite have transformed to a glass. The distribution of vesicles in shock-vitrified mica reveals escape of volatiles within the short duration of the shock experiment. It is noted that experimentally shocked biotite and muscovite undergo congruent melting. It is noted that the compositions of the glasses are similar to the unshocked micas except for volatiles (H2O loss and and K loss). These unusual glasses produced from mica can be quenched by rapid cooling conditions during the shock experiment. On the basis of the results, it is pointed out that the extremely low H2O content of tektites can be reconciled with a terrestrial origin by impact.

  8. Experimental investigations of elastohydrodynamic lubrication

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Dowson, D.

    1983-01-01

    Various experimental studies of elastohydrodynamic lubrication have been reviewed. The various types of machines used in these investigations, such as the disc, two and four ball, crossed-cylinders, and crossed-axes rolling disc machine, are described. The measurement of the most important parameters, such as film shape, film thickness, pressure, temperature, and traction, is considered. Determination of the film thickness is generally the most important of these effects since it dictates the extent to which the asperities on opposing surfaces can come into contact and thus has a direct bearing on wear and fatigue failure of the contacting surfaces. Several different techniques for measuring film thickness have been described, including electrical resistance, capacitance, X-ray, optical interferometry, laser beam diffraction, strain gage, and spring dynamometer methods. An attempt has been made to describe the basic concepts and limitations of each of these techniques. These various methods have been used by individual researchers, but there is no universally acceptable technique for measuring elastohydrodynamic film thickness. Capacitance methods have provided most of the reliable data for nominal line or rectangular conjunctions, but optical interferometry has proved to be the most effective procedure for elliptical contacts. Optical interferometry has the great advantage that it reveals not only the film thickness, but also details of the film shape over the complete area of the conjunction.

  9. Novel/experimental bariatric techniques.

    PubMed

    Thorell, Anders

    2014-01-01

    Due to the documented effects regarding durable and pronounced weight loss as well as improvement/resolution of obesity-associated morbidity, the number of bariatric surgical procedures performed has increased in an 'epidemiologic' fashion during the last decade. Most common/established procedures used today have well-documented effects but are all associated with technique-specific advantages as well as shortcomings. In particular, complications in the short as well as long term constitute a drive for continuous development of new techniques. A common feature of such new techniques is to reduce the degree of surgical trauma by being less invasive. Some of the new techniques used for bariatric treatment have been in clinical practice for a long time. However, due to the lack of controlled data with documentation of their efficacy and risk of complications, these are still to be considered as experimental. Other techniques are newly being introduced, and therefore data on their potential use for treatment of morbidly obese patients are limited. In this article, an overview of some of the most important of such new techniques is given. Some recently presented methodologies in which very sparse documentation is present, but which have been appreciated for being innovative and sometimes controversial, are also mentioned. PMID:24819498

  10. Majorana Thermosyphon Prototype Experimental Results

    SciTech Connect

    Fast, James E.; Reid, Douglas J.; Aguayo Navarrete, Estanislao

    2010-12-17

    Objective The Majorana demonstrator will operate at liquid Nitrogen temperatures to ensure optimal spectrometric performance of its High Purity Germanium (HPGe) detector modules. In order to transfer the heat load of the detector module, the Majorana demonstrator requires a cooling system that will maintain a stable liquid nitrogen temperature. This cooling system is required to transport the heat from the detector chamber outside the shield. One approach is to use the two phase liquid-gas equilibrium to ensure constant temperature. This cooling technique is used in a thermosyphon. The thermosyphon can be designed so the vaporization/condensing process transfers heat through the shield while maintaining a stable operating temperature. A prototype of such system has been built at PNNL. This document presents the experimental results of the prototype and evaluates the heat transfer performance of the system. The cool down time, temperature gradient in the thermosyphon, and heat transfer analysis are studied in this document with different heat load applied to the prototype.

  11. Escalation of aggression: experimental studies.

    PubMed

    Goldstein, J H; Davis, R W; Herman, D

    1975-01-01

    A finding commonly obtained in research using the Buss "aggression machine" is a main effect for trail blocks, indicating an escalation in shock intensity over trails. Theoretical explanations for this effect were tested in a modified verbal operant-conditioning situation. In Experiment 1, subjects could administer any of 10 levels of positive reinforcement to a "learner" for correct verbal responses or any of 10 levels of negative reinforcement to a learner for incorrect responses. Half of the subjects were required to begin with weak, half with strong, reinforcements. Results indicated that, regardless of condition, subjects gave more intense reinforcements as the learning trails progressed. Those who administered negative reinforcements devalued the learner relative to those who administered positive reinforcements. In Experiment 2, a role-playing procedure was used in which subjects administered either positive or negative reinforcements to a learner whose performance either did or did not improve over trials. Again, in all experimental groups, subjects administered increasingly intense reinforcements over trials. The results are interpreted as supporting a disinhibition theory of anti- and prosocial behavior.

  12. The Experimental MJO Prediction Project

    NASA Technical Reports Server (NTRS)

    Waliser, Duane; Weickmann, Klaus; Dole, Randall; Schubert, Siegfried; Alves, Oscar; Jones, Charles; Newman, Matthew; Pan, Hua-Lu; Roubicek, Andres; Saha, Suranjana; Smith, Cathy; VanDenDool, Huug; Vitart, Frederic; Wheeler, Matthew; Whitaker, Jeffrey

    2006-01-01

    Weather prediction is typically concerned with lead times of hours to days, while seasonal-to-interannual climate prediction is concerned with lead times of months to seasons. Recently, there has been growing interest in 'subseasonal' forecasts---those that have lead times on the order of weeks (e.g., Schubert et al. 2002; Waliser et al. 2003; Waliser et al. 2005). The basis for developing and exploiting subseasonal predictions largely resides with phenomena such as the Pacific North American (PNA) pattern, the North Atlantic oscillation (NAO), the Madden-Julian Oscillation (MJO), mid-latitude blocking, and the memory associated with soil moisture, as well as modeling techniques that rely on both initial conditions and slowly varying boundary conditions (e.g., tropical Pacific SST). An outgrowth of this interest has been the development of an Experimental MJO Prediction Project (EMPP). Th project provides real-time weather and climate information and predictions for a variety of applications, broadly encompassing the subseasonal weather-climate connection. Th focus is on the MJO because it represents a repeatable, low-frequency phenomenon. MJO's importance among the subseasonal phenomena is very similar to that of El Nino-Southern Oscillation(ENSO) among the interannual phenomena. This note describes the history and objectives of EMPP, its status,capabilities, and plans.

  13. Characterisation of some experimental silicones.

    PubMed

    Parker, S; Meththananda, I; Braden, M; Pearson, G J

    2006-12-01

    Release of antimicrobials/antibacterials like chlorhexidine diacetate (CHD) has proved successful in inhibiting Candidal colonisation of silicone-based biomaterials. However, their addition will increase water uptake and may compromise the mechanical integrity. Two experimental silicones (S1 and S2) differing only in the surface treatment of the filler, were investigated. Ultimate tensile strength (UTS), % elongation at break (Eb), Shore A hardness and, when doped with 1% CHD, water uptake and CHD release were measured. Elastic modulus (E) was calculated from the hardness measurements. There was no significant difference in UTS and Eb between the two materials. However S1 had a higher hardness (30.6 +/- 0.97) and thus E (0.76 MPa) than S2 (hardness = 23.8 +/- 0.48, E = 0.45 MPa). Water uptake for S2 (0.6%) was higher than for S2 (0.1) and addition of CHD dramatically increased the uptake of both (S1 = 3.1%, S2 = 4.0%). Release of CHD was higher for S2 (30%) than S1 (27%). Equating osmotic pressure within the droplets with elastic restraining force gave an extension ratio of 1.95 for S1 and 5.39 for S2. Thus, addition of a hydrophilic agent can compromise the mechanical integrity of low modulus silicones.

  14. Inverted annular flow experimental study

    SciTech Connect

    De Jarlais, G.; Ishii, M.

    1985-04-01

    Steady-state inverted annular flow of Freon 113 in up flow was established in a transparent test section. Using a special inlet configuration consisting of long aspect-ratio liquid nozzles coaxially centered within a heated quartz tube, idealized inverted annular flow initial geometry (cylindrical liquid core surrounded by coaxial annulus of gas) could be established. Inlet liquid and gas flowrates, liquid subcooling, and gas density (using various gas species) were measured and varied systematically. The hydrodynamic behavior of the liquid core, and the subsequent downstream break-up of this core into slugs, ligaments and/or droplets of various sizes, was observed. In general, for low inlet liquid velocities it was observed that after the initial formation of roll waves on the liquid core surface, an agitated region of high surface area, with attendant high momentum and energy transfers, occurs. This agitated region appears to propagate downsteam in a quasi-periodic pattern. Increased inlet liquid flow rates, and high gas annulus flow rates tend to diminish the significance of this agitated region. Observed inverted annular flow (and subsequent downstream flow pattern) hydrodynamic behavior is reported, and comparisons are drawn to data generated by previous experimenters studying post-CHF flow.

  15. Experimental Evolution of Species Recognition.

    PubMed

    Rogers, David W; Denton, Jai A; McConnell, Ellen; Greig, Duncan

    2015-06-29

    Sex with another species can be disastrous, especially for organisms that mate only once, like yeast. Courtship signals, including pheromones, often differ between species and can provide a basis for distinguishing between reproductively compatible and incompatible partners. Remarkably, we show that the baker's yeast Saccharomyces cerevisiae does not reject mates engineered to produce pheromones from highly diverged species, including species that have been reproductively isolated for up to 100 million years. To determine whether effective discrimination against mates producing pheromones from other species is possible, we experimentally evolved pheromone receptors under conditions that imposed high fitness costs on mating with cells producing diverged pheromones. Evolved receptors allowed both efficient mating with cells producing the S. cerevisiae pheromone and near-perfect discrimination against cells producing diverged pheromones. Sequencing evolved receptors revealed that each contained multiple mutations that altered the amino acid sequence. By isolating individual mutations, we identified specific amino acid changes that dramatically improved discrimination. However, the improved discrimination conferred by these individual mutations came at the cost of reduced mating efficiency with cells producing the S. cerevisiae pheromone, resulting in low fitness. This tradeoff could be overcome by simultaneous introduction of separate mutations that improved mating efficiency alongside those that improved discrimination. Thus, if mutations occur sequentially, the shape of the fitness landscape may prevent evolution of the optimal phenotype--offering a possible explanation for the poor discrimination of receptors found in nature.

  16. Experimental evolution meets marine phytoplankton.

    PubMed

    Reusch, Thorsten B H; Boyd, Philip W

    2013-07-01

    Our perspective highlights potentially important links between disparate fields-biological oceanography, climate change research, and experimental evolutionary biology. We focus on one important functional group-photoautotrophic microbes (phytoplankton), which are responsible for ∼50% of global primary productivity. Global climate change currently results in the simultaneous change of several conditions such as warming, acidification, and nutrient supply. It thus has the potential to dramatically change phytoplankton physiology, community composition, and may result in adaptive evolution. Although their large population sizes, standing genetic variation, and rapid turnover time should promote swift evolutionary change, oceanographers have focussed on describing patterns of present day physiological differentiation rather than measure potential adaptation in evolution experiments, the only direct way to address whether and at which rate phytoplankton species will adapt to environmental change. Important open questions are (1) is adaptation limited by existing genetic variation or fundamental constraints? (2) Will complex ecological settings such as gradual versus abrupt environmental change influence adaptation processes? (3) How will increasing environmental variability affect the evolution of phenotypic plasticity patterns? Because marine phytoplankton species display rapid acclimation capacity (phenotypic buffering), a systematic study of reaction norms renders them particularly interesting to the evolutionary biology research community.

  17. Experimental Tests Of Paleoclassical Transport

    SciTech Connect

    Callen, J D; Anderson, J K; Arlen, T C; Bateman, G; Budny, R V; Fujita, T; Greenfield, C M; Greenwald, M; Groebner, R J; Hill, D N; Hogeweij, G D; Kaye, S M; Kritz, A H; Lazarus, E A; Leonard, A C; Mahdavi, M A; McLean, H S; Osborne, T H; Pankin, A Y; Petty, C C; Sarff, J S; St. John, H E; Stacey, W M; Stutman, D; Synakowski, E J; Tritz, K

    2006-09-12

    Predictions of the recently developed paleoclassical transport model are compared with data from many toroidal plasma experiments: electron heat diffusivity in DIII-D, C-Mod and NSTX ohmic and near-ohmic plasmas; transport modeling of DIII-D ohmic-level discharges and of the RTP ECH 'stair-step' experiments with eITBs at low order rational surfaces; investigation of a strong eITB in JT-60U; H-mode Te edge pedestal properties in DIII-D; and electron heat diffusivities in non-tokamak experiments (NSTX/ST, MST/RFP, SSPX/spheromak). The radial electron heat transport predicted by the paleoclassical model is found to agree with a wide variety of ohmic-level experimental results and to set the lower limit (within a factor {approx} 2) for the radial electron heat transport in most resistive, current-carrying toroidal plasmas -- unless it is exceeded by fluctuation-induced transport, which often occurs in the edge of L-mode plasmas and when the electron temperature is high ({approx}>T{sub e}{sup crit} {approx}B{sup 2/3}{bar {alpha}}{sup 1/2} keV) because then paleoclassical transport becomes less than gyro-Bohm-level anomalous transport.

  18. Experimental overview of axion searches

    SciTech Connect

    van Bibber, K.

    1995-06-28

    Experimental methods to search for the ``invisible axion`` (f{sub a} {much_gt} 250 GeV) are reviewed. The report focuses on the axion-photon coupling, both for laboratory experiments as well as those looking for stellar or cosmologically produced axions. The conclusion is that while the axion-photon mixing in principle would permit laboratory axion searches which are broadband in mass, in fact no such experiment could have the sensitivity to the axion, where m{sub afa} {approx} m{sub {pi}f{pi}}. The only experiments which promise to have any chance to find the axion are the microwave cavity experiments, which presume axions to constitute our galactic halo dark matter. The conversion of axions into a monochromatic microwave signal in a resonant circuit affords the experiment the extraordinary sensitivity required to see the axion, at the expense of being narrow-band in mass, i.e. a tuning experiment. Two such efforts are underway in the world.

  19. Experimental Calcification of the Myocardium

    PubMed Central

    Bonucci, Ermanno; Sadun, Raffaele

    1973-01-01

    Focal areas of calcification are frequent in rat myocardium 30 and 60 days after administration of dihydrotachysterol. These areas are PAS-positive, stain deeply with alcian blue and show high affinity for colloidal iron. Calcification is almost completely confined to intracellular structures. Small clusters of needle-shaped crystals are first found in apparently undamaged mitochondria in undamaged myocardial cells. When all the mitochondria are calcified, the cell degenerates, and inorganic crystals are laid down in relationship with its myofilaments. In other myocardial cells, clusters of amorphous or finely granular inorganic substance are found in both mitochondria and myofibrils. Both structures show signs of advanced degeneration. Inorganic substance has only occasionally been found within the structures of the sarcoplasmic reticulum. These structures do not seem to be involved in myocardial calcification under the present experimental conditions. Calcification of myocardial cells gives rise to a cellular reaction. Many macrophagic cells surround the calcified areas, which are rapidly reabsorbed. The present results show that myocardial mitochondria are actively engaged in controlling the intracellular concentration and movement of calcium ions. Their role in the myocardial contraction-relaxation cycle and the possible mechanism of myocardial calcification are discussed. ImagesFig 14Fig 1Fig 2Fig 3Fig 4Fig 5Fig 6Fig 7Fig 8Fig 9Fig 10Fig 11Fig 12Fig 13 PMID:4197422

  20. AN EXPERIMENTAL STUDY OF DIATHERMY

    PubMed Central

    Christie, Ronald V.; Ehrich, Wilhelm; Binger, Carl A. L.

    1928-01-01

    1. An experimental pneumonia with more or less lobar distribution has been produced in dogs by the method of intrabronchial insufflation of B. friedlænderi, Type B, and Pneumococcus, Type I. 2. Such dogs as showed evidences of a pulmonary lesion when photographed by x-ray were selected for lung temperature measurements. 3. Measurements of lung temperature were made by means of thermocouples before and during diathermy. 4. The thermocouples which recorded the temperature in the consolidated lobes showed in most instances a more rapid rate of heating during diathermy than those in the normal lobes. The final increase in temperature in the pathological lobes over the normal lobes amounted to slightly more than 1°C. 5. When local heating occurred during diathermy it was of the order of magnitude found in a lung in which the branch of the pulmonary artery supplying it had been clamped. 6. Histological examination of the lungs showed the pathological reaction to consist of intraalveolar exudate composed of polymorphonuclear leucocytes and desquamated alveolar epithelium. In some sections the exudate was sufficient to cause compression and emptying of the alveolar capillaries. 7. The local heating, we believe, depends upon this ischemic state of the smaller vessels. 8. Further evidence for an imparied circulation in the pneumonic lung is furnished by injection preparations in which the uninjected area corresponded exactly to the gross pathological lesion. PMID:19869441

  1. Experimental research control software system

    NASA Astrophysics Data System (ADS)

    Cohn, I. A.; Kovalenko, A. G.; Vystavkin, A. N.

    2014-05-01

    A software system, intended for automation of a small scale research, has been developed. The software allows one to control equipment, acquire and process data by means of simple scripts. The main purpose of that development is to increase experiment automation easiness, thus significantly reducing experimental setup automation efforts. In particular, minimal programming skills are required and supervisors have no reviewing troubles. Interactions between scripts and equipment are managed automatically, thus allowing to run multiple scripts simultaneously. Unlike well-known data acquisition commercial software systems, the control is performed by an imperative scripting language. This approach eases complex control and data acquisition algorithms implementation. A modular interface library performs interaction with external interfaces. While most widely used interfaces are already implemented, a simple framework is developed for fast implementations of new software and hardware interfaces. While the software is in continuous development with new features being implemented, it is already used in our laboratory for automation of a helium-3 cryostat control and data acquisition. The software is open source and distributed under Gnu Public License.

  2. [HERNIOPLASTIC MORFOLOGICAL FEATURES (EXPERIMENTAL STADY)].

    PubMed

    Gogoladze, M; Kiladze, M; Chkhikvadze, T; Tsivtsivadze, L; Jiqia, D

    2016-05-01

    Despite many years of experience in the field of hernia surgical treatment there still exist many unsolved problems such as a safe and non infected closure of defects of abdominal cavity wall. The aim of the study was to improve the result of treatment of abdominal wall hernias with the use of new antiseptic polymer, bio-composite protective mesh membrane covered with coladerm+chlorhexidine. Experimental study involved 21 rabbits. Meshes were fixed on anterior abdominal wall according to the following schewe: Option I: mesh size 10-20mm was put into both the groin area of the rabbits. Option II: A light standart mesh grid size 10-20mm covered with coladerm was placed on both sides of abdominal wall of the rabbits. Option III: A light mesh, covered with oladerm+Chlorhexidine was placed in to the abdominal wall of the rabbits. Removal dates of taking the animals from experiments were 14th, 30th, 45th, 90th and 180th days for further histomorpological and bacteriological research. The best result from these options was when implants we covered with coladerm+Chlorhexidine, which was shown on follow up period. In third control group experessed strong connective tissue formatting stromis picture,wich is the main task of modern hernia plastic. It is expected that new bio-composite meshes, covered with coladerm+Chlorhexidine, may be succesfuly used in clinical practice, which will reduce infectious complications of meshes and problems associated with them. PMID:27348172

  3. Angiogenesis and experimental hepatic fibrosis.

    PubMed

    Lemos, Queli Teixeira; Andrade, Zilton A

    2010-08-01

    Angiogenesis is a basic change occurring during repair by granulation tissue. This process seems to precede fibrosis formation in most types of chronic liver disease. To examine its presence and significance in different types of hepatic insults, this paper sought to identify the presence, evolution and peculiarities of angiogenesis in the most common experimental models of hepatic fibrosis. The characterization of cells, vessels and extracellular matrix and the identification of factors associated with endothelium (factor VIII RA), vascular basement membrane, other components of the vascular walls (actin, elastin) and the presence of the vascular-endothelial growth factor were investigated. The models examined included Capillaria hepatica septal fibrosis, whole pig serum injections, carbon tetrachloride administration, main bile duct ligation and Schistosoma mansoni infection. The first four models were performed in rats, while the last used mice. All models studied exhibited prominent angiogenesis. The most evident relationship between angiogenesis and fibrosis occurred with the C. hepatica model due to circumstances to be discussed. Special attention was paid to the presence of pericytes and to their tendency to become detached from the vascular wall and be transformed into myofibroblasts, which is a sequence of events that explains the decisive role angiogenesis plays in fibrosis.

  4. Compendium of Experimental Cetane Numbers

    SciTech Connect

    Yanowitz, J.; Ratcliff, M. A.; McCormick, R. L.; Taylor, J. D.; Murphy, M. J.

    2014-08-01

    This report is an updated version of the 2004 Compendium of Experimental Cetane Number Data and presents a compilation of measured cetane numbers for pure chemical compounds. It includes all available single compound cetane number data found in the scientific literature up until March 2014 as well as a number of unpublished values, most measured over the past decade at the National Renewable Energy Laboratory. This Compendium contains cetane values for 389 pure compounds, including 189 hydrocarbons and 201 oxygenates. More than 250 individual measurements are new to this version of the Compendium. For many compounds, numerous measurements are included, often collected by different researchers using different methods. Cetane number is a relative ranking of a fuel's autoignition characteristics for use in compression ignition engines; it is based on the amount of time between fuel injection and ignition, also known as ignition delay. The cetane number is typically measured either in a single-cylinder engine or a constant volume combustion chamber. Values in the previous Compendium derived from octane numbers have been removed, and replaced with a brief analysis of the correlation between cetane numbers and octane numbers. The discussion on the accuracy and precision of the most commonly used methods for measuring cetane has been expanded and the data has been annotated extensively to provide additional information that will help the reader judge the relative reliability of individual results.

  5. Experimental investigation of plasmofluidic waveguides

    SciTech Connect

    Ku, Bonwoo; Kwon, Min-Suk; Shin, Jin-Soo

    2015-11-16

    Plasmofluidic waveguides are based on guiding light which is strongly confined in fluid with the assistance of a surface plasmon polariton. To realize plasmofluidic waveguides, metal-insulator-silicon-insulator-metal (MISIM) waveguides, which are hybrid plasmonic waveguides fabricated using standard complementary metal-oxide-semiconductor technology, are employed. The insulator of the MISIM waveguide is removed to form 30-nm-wide channels, and they are filled with fluid. The plasmofluidic waveguide has a subwavelength-scale mode area since its mode is strongly confined in the fluid. The waveguides are experimentally characterized for different fluids. When the refractive index of the fluid is 1.440, the plasmofluidic waveguide with 190-nm-wide silicon has propagation loss of 0.46 dB/μm; the coupling loss between it and an ordinary silicon photonic waveguide is 1.79 dB. The propagation and coupling losses may be reduced if a few fabrication-induced imperfections are removed. The plasmofluidic waveguide may pave the way to a dynamically phase-tunable ultracompact device.

  6. On Experimental Thermal Analysis of Solid Materials

    NASA Astrophysics Data System (ADS)

    Koštial, Pavel; Špička, Ivo; Jančikova, Zora; Valiček, Jan; Harničarova, Marta; Hlinka, Josef

    2014-12-01

    The paper is devoted to the presentation of a method for measurement of thermal conductivity k, specific heat capacity cp, and thermal diffusivity applying the lumped capacitance model (LCM) as a special case of Newton's model of cooling. At the specific experimental conditions resulting from the theoretical analysis of the used model, we present a method for experimental determination of all three above mentioned thermal parameters for materials with different thermal transport properties. The input experimental data provide a cooling curve of the tested material. The evaluation of experimental data is realized by software, the fundamental features of which are presented here. The statistical analysis of experimental data was performed.

  7. Experimental Studies in Ice Nucleation

    NASA Astrophysics Data System (ADS)

    Wright, Timothy Peter

    Ice nuclei play a critical role in the formation of precipitation in mixed phase clouds. Modification of IN concentrations can lead to changes in cloud lifetimes and precipitation size. Presented in this study are experimental investigations into ice nuclei in an ongoing effort to reduce the uncertainties that ice nuclei have on cloud processes and climate. This research presents a new version of the cold stage drop freezing assay to investigate the time-dependence of heterogeneous nucleation. The temperature range for the instrument spans from the melting point of water to the homogeneous freezing limit of ˜-38 deg C. Temperature stability for the instrument allowed for experimental operation for up to four days while interrogating the same sample. Up to a one hundred fold increase in the number of analyzed drops was accomplished through an in-house written automated drop freezing detection software package. Combined instrument design improvements allow for the analysis of IN concentrations down to ˜10-8 ice nuclei per picoliter of sample water. A new variant of the multiple-component stochastic model for heterogeneous ice nucleation was used to investigate the time dependence of heterogeneous freezing processes. This was accomplished by analyzing how the changes in the cooling rate can impact the observed nucleation rate. The model employed four material-dependent parameters to accurately capture the observed freezing of water drops containing Arizona Test Dust. The parameters were then used to accurately predict the freezing behavior of the drops in time dependent experiments. The time dependence freezing of a wide range of materials was then investigated. These materials included the minerals montmorillonite and kaolinite, the biological proxy ice nuclei contained within the product Icemax, and flame soot generated from the incomplete combustion of ethylene gas. The time dependence for ice nuclei collected from rainwater samples was also investigated. The

  8. Magnetic Launch Assist Experimental Track

    NASA Technical Reports Server (NTRS)

    1999-01-01

    In this photograph, a futuristic spacecraft model sits atop a carrier on the Magnetic Launch Assist System, formerly known as the Magnetic Levitation (MagLev) System, experimental track at the Marshall Space Flight Center (MSFC). Engineers at MSFC have developed and tested Magnetic Launch Assist technologies that would use magnetic fields to levitate and accelerate a vehicle along a track at very high speeds. Similar to high-speed trains and roller coasters that use high-strength magnets to lift and propel a vehicle a couple of inches above a guideway, a Magnetic Launch Assist system would electromagnetically drive a space vehicle along the track. A full-scale, operational track would be about 1.5-miles long and capable of accelerating a vehicle to 600 mph in 9.5 seconds. This track is an advanced linear induction motor. Induction motors are common in fans, power drills, and sewing machines. Instead of spinning in a circular motion to turn a shaft or gears, a linear induction motor produces thrust in a straight line. Mounted on concrete pedestals, the track is 100-feet long, about 2-feet wide, and about 1.5-feet high. The major advantages of launch assist for NASA launch vehicles is that it reduces the weight of the take-off, the landing gear, the wing size, and less propellant resulting in significant cost savings. The US Navy and the British MOD (Ministry of Defense) are planning to use magnetic launch assist for their next generation aircraft carriers as the aircraft launch system. The US Army is considering using this technology for launching target drones for anti-aircraft training.

  9. [Regeneration of planarians: experimental object].

    PubMed

    Sheĭman, I M; Kreshchenko, I D

    2015-01-01

    We discuss the expediency of using invertebrates, such as flatworms and planarians, as experimental objects. Free-living planarian flatworms (phylum Platyhelminthes, class Turbellaria) are invertebrate animals in which a bilateral symmetry appears for the first time in evolution and organs and tissues form. As the highest ecological link of the food chain--predators--these animals are characterized by a set of behavioral reactions controlled by a differentiated central nervous system. Planarians have unsurpassed ability to regenerate lost or damaged body parts. Owing to the ease of their breeding and their convenience for manipulations, these animals are used to study the influence of chemical and physical factors on the processes of life, growth, and reproduction. Currently, planarians are recognized as a model for biological research in the field of regeneration, stem cell biology, study of their proliferation and differentiation, as well as the regulatory mechanisms of morphogenetic processes. The genome of the planarian Schmidtea mediterranea was fully sequenced, which opened up the opportunity to work with this object at the molecular biological level. Furthermore, planarians are used in neurobiological and toxicological studies, in studying the evolutionary aspects of centralization of the nervous system, mechanisms of muscle contraction, and in the development of new antiparasitic drugs. This review aims to demonstrate the relevance and diversity of research conducted on simple biological objects--planarians--to awider audience to show the historical continuity of these studies and their wide geographical distribution and to focus on the studies carried out in Russia, which, as a rule, are not included in the foreign reviews on planarian regeneration.

  10. Experimental Infrasound Studies in Nevada

    NASA Astrophysics Data System (ADS)

    Herrin, E. T.; Negraru, P. T.; Golden, P.; Williams, A.

    2009-12-01

    An experimental propagation study was carried out in Nevada in June 2009 on Julian days 173-177. During this field experiment we deployed 16 single channel digital infrasound recorders to monitor the munitions disposal activities near Hawthorne, NV. The sensors were deployed in a single line and placed approximately 12 km apart at distances ranging from 2 to 177 km. A four element semi-permanent infrasound array named FNIAR was installed approximately 154 km north of the detonation site in line with the individual temporary recorders. Tropospheric arrivals were observed during all days of the experiment, but during day 176 the observed arrivals had very large amplitudes. A large signal was observed at 58 km from the detonation site with amplitude as large as 4 Pascals, while at 94 km no signal was observed. At FNIAR the amplitude of the tropospheric arrival was 1 Pascal. During this day meteorological data acquired in the propagation path showed a strong jet stream to the north. On day 177 we were not able to identify tropospheric arrivals beyond 34 km, but at stations beyond 152 km we observed stratospheric arrivals. Continuous monitoring of these signals at FNIAR shows that stratospheric arrivals are the most numerous. In a two month period, from 06/15/2009 to 08/15/2009 there were 35 operational days at the Hawthorne disposal facility resulting in 212 explosions with known origin times. Based on the celerity values there were 115 explosions that have only stratospheric arrivals (celerities of 300-275 m/s), 72 explosions with both tropospheric (celerities above 330 m/s) and stratospheric arrivals, 20 explosions that were not detected and five explosions that have only tropospheric arrivals.

  11. Epistemological Dizziness in the Psychology Laboratory: Lively Subjects, Anxious Experimenters, and Experimental Relations, 1950-1970.

    PubMed

    Morawski, Jill

    2015-09-01

    Since the demise of introspective techniques in the early twentieth century, experimental psychology has largely assumed an administrative arrangement between experimenters and subjects wherein subjects respond to experimenters' instructions and experimenters meticulously constrain that relationship through experimental controls. During the postwar era this standard arrangement came to be questioned, initiating reflections that resonated with Cold War anxieties about the nature of the subjects and the experimenters alike. Albeit relatively short lived, these interrogations of laboratory relationships gave rise to unconventional testimonies and critiques of experimental method and epistemology. Researchers voiced serious concerns about the honesty and normality of subjects, the politics of the laboratory, and their own experimental conduct. Their reflective commentaries record the intimacy of subject and experimenter relations and the plentiful cultural materials that constituted the experimental situation, revealing the permeable boundaries between laboratory and everyday life. PMID:26685518

  12. [Experimental antitriatomic program in Santiago].

    PubMed

    Neghme, A; Schenone, H; Villarroel, F; Rojas, A

    1991-01-01

    The rural migration to urban centers occurred since the 40s in many Latin American countries, including Santiago the capital city of Chile, originated a growing belt of premises built with light poor material (the rests of previous rural habitations, mud, pieces of timber, plastic and cardboard for walls, and cane stalks and artificial clinkstones for roofs) giving raise to many types of slums. This situation facilitated the passive transport of the different instars, including eggs, of triatomine bugs. Due to the fact that in the 1959-1960 warm seasons, the Santiago province health institutions had received an increasing reported number of triatomine bugs (Triatoma infestans) in dwellings from different periurban, even urban and rural sections of the province, the central local health authorities with the advise of the University of Chile, Department of Parasitology decided to carry out an experimental program against these vectors of Chagas' disease. The program consisted basically in an spray and thorough application of liquid forms (emulsion, suspension, solution) of 1% lindane (average > or = 500 mg per 1 m2), depending on the material of the constructions, to all the surfaces of walls, ceilings, attics and peridomiciliary structures of all the infested dwellings in a sector and those located less than 100 m around. In order to reach triatomine bugs not affected, for different reasons, in the first spraying, a second application, identical to the first was performed to the total number of premises between 30 and 120 days later. Periodical evaluations were made, and positive dwellings found and neighboring ones were sprayed again. During insecticide applications adequate protection measures for spraying workers, inhabitants, domestic animals, household goods and food were adopted. All the steps of the program were accompanied by health education activities directed to individuals, families, school teachers and community institutions, tending to motivate the

  13. Experimental reproduction of tsunami deposit

    NASA Astrophysics Data System (ADS)

    Yoshii, T.; Matsuyama, M.; Tanaka, S.

    2015-12-01

    in reproducing tsunami deposit and would show typical pattern of topography change and deposition caused by the tsunami incursion. The experimental method used in this study and the obtained deposition patterns will help understanding the relationship between hydraulic condition and resulting tsunami deposition.

  14. Mars Radiator Characterization Experimental Program

    NASA Technical Reports Server (NTRS)

    Witte, Larry C.; Hollingsworth, D. Keith

    2004-01-01

    Radiators are an enabling technology for the human exploration and development of the moon and Mars. As standard components of the heat rejection subsystem of space vehicles, radiators are used to reject waste heat to space and/or a planetary environment. They are typically large components of the thermal control system for a space vehicle or human habitation facility, and in some cases safety factors are used to oversize them when the operating environment cannot be fully characterized. Over-sizing can impose significant weight and size penalties that might be prohibitive for future missions. Radiator performance depends on the size of the radiator surface, its emittance and absorptance, the radiator temperature, the effective sky temperature surrounding the radiator, solar radiation and atmospheric irradiation levels, convection to or from the atmosphere (on Mars), and other conditions that could affect the nature of the radiator surface, such as dust accumulation. Most particularly, dust is expected to be a major contributor to the local environmental conditions on either the lunar or Martian surface. This conclusion regarding Mars is supported by measurements of dust accumulation on the Mars Sojourner Rover solar array during the Pathfinder mission. This Final Report describes a study of the effect of Martian dust accumulation on radiator performance. It is comprised of quantitative measurements of effective emittance for a range of dust accumulation levels on surfaces of known emittance under clean conditions. The test radiator coatings were Z-93P, NS-43G, and Silver Teflon (10 mil) film. The Martian dust simulant was Carbondale Red Clay. Results were obtained under vacuum conditions sufficient to reduce convection effects virtually to zero. The experiments required the development of a calorimetric apparatus that allows simultaneous measurements of the effective emittance for all the coatings at each set of experimental conditions. A method of adding dust to

  15. Experimental generation of volcanic lightning

    NASA Astrophysics Data System (ADS)

    Cimarelli, Corrado; Alatorre-Ibargüengoitia, Miguel; Kueppers, Ulrich; Scheu, Bettina; Dingwell, Donald B.

    2014-05-01

    the plume that emerge as the key variables in volcanic lightning generation. A proportionality between fine ash content of the jet and number of lightning strikes is also evident in our experiments. This first recorded experimental generation of volcanic lightning means that rapid progress can now be expected (under controlled laboratory conditions) in understanding electrical phenomena produced during explosive volcanic eruptions. This in turn may aid the development of lightning monitoring systems for the forecasting of volcanic ash emissions into the atmosphere. Furthermore, our experiments are significant for the investigation of self-charging mechanism of particles that are relevant for atmospheric phenomena (such as dust storms) on Earth and other planetary bodies.

  16. Experimental Aerobraking with Venus Express

    NASA Astrophysics Data System (ADS)

    Svedhem, Hakan

    2013-10-01

    Venus Express has successfully orbited Venus in its polar 24 hour, 250km by 66000 km, orbit since April 2006 and has provided a wealth of new data from our sister planet. Approaching the end of the mission we are now planning an experimental campaign dedicated to aerobraking at altitudes down to as low as about 130km. These low pericentre passes will provide direct measurements of density, temperature, magnetic field and energetic particles in a region not accessible by other methods. Experience of operations and studies of spacecraft responses will be valuable knowledge for possible future missions that might need this techniques as a part of its nominal operations. Aerobraking was considered in the early design phase of the mission but it was fairly soon realised that the nominal mission would not need this. However, a few important design features were maintained in order to allow for this in case it should be needed at a later stage. The inherently stable geometry of the spacecraft configuration and the inclusion of a software mode for aerobraking are the two most important elements from this early design phase. An recent study by industry has determined the constraints for the spacecraft and identified several potential scenarios. The present highly elliptical orbit has as one of its inherent features a downward drift of the pericentre altitude of between 1 and 4 km/day. However, at certain times, when the Sun is in the orbital plane, this drift disappears for a period of up to two weeks. This is a very well suited time to carry out these initial experiments as it is makes operations safer and it reduces the heat input on the spacecraft as the solar panels will be edge-on towards the sun during the aerobraking. Already a number of low altitude operations have been carried out during the so called atmospheric drag campaigns. The spacecraft has then dipped down to altitudes as low as 165 km and a good characterisation of this region has been performed. This

  17. Charge of the containerless experimentation in microgravity

    NASA Technical Reports Server (NTRS)

    Lee, Mark C.

    1990-01-01

    The experimentation was undertaken to study the elimination or reduction of surface contamination for which there is adequate Earth-based technology along with the reduction of dynamic nucleation for which there a paucity of reliable data. One objective is to delineate scientific justification of the U.S. Containerless Experimentation Program in Microgravity for the next decade and beyond. Another objective is for the guidance of NASA to define the next generation of containerless experimentation instruments in microgravity.

  18. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    .... Experimental certificates are issued for the following purposes: (a) Research and development. Testing new... from racing events. (f) Market surveys. Use of aircraft for purposes of conducting market...

  19. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... Experimental certificates are issued for the following purposes: (a) Research and development. Testing new... from racing events. (f) Market surveys. Use of aircraft for purposes of conducting market...

  20. Experimental methods for identifying failure mechanisms

    NASA Technical Reports Server (NTRS)

    Daniel, I. M.

    1983-01-01

    Experimental methods for identifying failure mechanisms in fibrous composites are studied. Methods to identify failure in composite materials includes interferometry, holography, fractography and ultrasonics.

  1. ISABELLE. Volume 3. Experimental areas, large detectors

    SciTech Connect

    Not Available

    1981-01-01

    This section presents the papers which resulted from work in the Experimental Areas portion of the Workshop. The immediate task of the group was to address three topics. The topics were dictated by the present state of ISABELLE experimental areas construction, the possibility of a phased ISABELLE and trends in physics and detectors.

  2. Experimental methodologies to support aircraft icing analysis

    NASA Technical Reports Server (NTRS)

    Hansman, R. John, Jr.; Kirby, Mark S.

    1987-01-01

    The experimental methodologies are illustrated by graphs, charts and line drawings. Typical ultrasonic echo signals for dry and wet ice growth, ice accretion rates for various tunnel configurations, the experimental configuration for flight tests of the ultrasonic measuring system and heat balance models used to predict ice growth are among the topics that are illustrated and briefly discussed.

  3. Valuable lessons-learned in transcriptomics experimentation

    PubMed Central

    Bruning, Oskar; Rauwerda, Han; Dekker, Rob J; de Leeuw, Wim C; Wackers, Paul F K; Ensink, Wim A; Jonker, Martijs J; Breit, Timo M

    2015-01-01

    We have collected several valuable lessons that will help improve transcriptomics experimentation. These lessons relate to experiment design, execution, and analysis. The cautions, but also the pointers, may help biologists avoid common pitfalls in transcriptomics experimentation and achieve better results with their transcriptome studies. PMID:26098945

  4. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Experimental wine. 24.77 Section 24.77 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Administrative and Miscellaneous Provisions Tax Exempt Wine § 24.77 Experimental wine. (a) General. Any...

  5. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Experimental wine. 24.77 Section 24.77 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL WINE Administrative and Miscellaneous Provisions Tax Exempt Wine § 24.77 Experimental wine. (a) General. Any...

  6. Quasi-Experimental Designs for Causal Inference

    ERIC Educational Resources Information Center

    Kim, Yongnam; Steiner, Peter

    2016-01-01

    When randomized experiments are infeasible, quasi-experimental designs can be exploited to evaluate causal treatment effects. The strongest quasi-experimental designs for causal inference are regression discontinuity designs, instrumental variable designs, matching and propensity score designs, and comparative interrupted time series designs. This…

  7. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Experimental wine. 24.77... OF THE TREASURY LIQUORS WINE Administrative and Miscellaneous Provisions Tax Exempt Wine § 24.77 Experimental wine. (a) General. Any scientific university, college of learning, or institution of...

  8. The Experimental Design Ability Test (EDAT)

    ERIC Educational Resources Information Center

    Sirum, Karen; Humburg, Jennifer

    2011-01-01

    Higher education goals include helping students develop evidence based reasoning skills; therefore, scientific thinking skills such as those required to understand the design of a basic experiment are important. The Experimental Design Ability Test (EDAT) measures students' understanding of the criteria for good experimental design through their…

  9. Experimental Influence Coefficients and Vibration Modes

    NASA Technical Reports Server (NTRS)

    Weidman, Deene J.; Kordes, Eldon E.

    1959-01-01

    Test results are presented for both symmetrical and antisymmetrical static loading of a wing model mounted on a three-point support system. The first six free-free vibration modes were determined experimentally. A comparison is made of the symmetrical nodal patterns and frequencies with the symmetrical nodal patterns and frequencies calculated from the experimental influence coefficients.

  10. Optimizing Experimental Designs: Finding Hidden Treasure.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Classical experimental design theory, the predominant treatment in most textbooks, promotes the use of blocking designs for control of spatial variability in field studies and other situations in which there is significant variation among heterogeneity among experimental units. Many blocking design...

  11. The 1985 Get Away Special Experimenter's Symposium

    NASA Technical Reports Server (NTRS)

    Thomas, L. R. (Editor); Mosier, F. L. (Editor)

    1986-01-01

    The 1985 Get Away Special (GAS) Experimenter's Symposium provided a formal opportunity for GAS experimenters to share the results of their projects. The focus is on payloads that have been flown on Shuttle missions, and on GAS payloads that will be flown in the near future.

  12. Assessing Students' Experimentation Processes in Guided Inquiry

    ERIC Educational Resources Information Center

    Emden, Markus; Sumfleth, Elke

    2016-01-01

    In recent science education, experimentation features ever more strongly as a method of inquiry in science classes rather than as a means to illustrate phenomena. Ideas and materials to teach inquiry abound. Yet, tools for assessing students' achievement in their processes of experimentation are lacking. The present study assumes a basal,…

  13. New model systems for experimental evolution.

    PubMed

    Collins, Sinéad

    2013-07-01

    Microbial experimental evolution uses a few well-characterized model systems to answer fundamental questions about how evolution works. This special section highlights novel model systems for experimental evolution, with a focus on marine model systems that can be used to understand evolutionary responses to global change in the oceans.

  14. Experimental Mathematics for the First Year Student

    ERIC Educational Resources Information Center

    Brown, David

    2014-01-01

    We describe a course that highlights mathematical experimentation as an introductory course for first year mathematics majors. We discuss the benefits of an experimental approach as an alternate pathway into the mathematics major. We also explain how this course serves as a gentle lead-in to later research experiences.

  15. The Hunterian Laboratory of Experimental Medicine.

    PubMed

    Ro, Kevin; Cameron, John L; Yeh, Michael W

    2011-05-01

    The Hunterian Laboratory of Experimental Medicine, established at the Johns Hopkins Hospital in 1905, played a central role in the early history of American surgery. Created primarily by William Halsted with the help of Harvey Cushing, the Laboratory was a cornerstone of experimental surgical research as well as surgical education. This article examines the conception and early years of the Laboratory. PMID:21451394

  16. Valuable lessons-learned in transcriptomics experimentation.

    PubMed

    Bruning, Oskar; Rauwerda, Han; Dekker, Rob J; de Leeuw, Wim C; Wackers, Paul F K; Ensink, Wim A; Jonker, Martijs J; Breit, Timo M

    2015-01-01

    We have collected several valuable lessons that will help improve transcriptomics experimentation. These lessons relate to experiment design, execution, and analysis. The cautions, but also the pointers, may help biologists avoid common pitfalls in transcriptomics experimentation and achieve better results with their transcriptome studies.

  17. The 1988 Get Away Special Experimenter's Symposium

    NASA Technical Reports Server (NTRS)

    Thomas, Lawrence R. (Editor); Mosier, Frances L. (Editor)

    1988-01-01

    The Get Away Special (GAS) Experimenter's Symposium was held to provide a formal opportunity for GAS experimenters to share the results of their projects. The focus of this symposium is on payloads that have been flown on shuttle missions and on GAS payloads that will be flown in the future. Experiment design and payload integration issues are also examined.

  18. A new dimension in space experimentation

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Space experimentation, cosmic origins, the long-term effects of the space environment on living things, the long-term effects of space environment on materials and hardware, seeds in space, power generation in space, experimentation with crystals, and thermal control are discussed.

  19. The 1987 Get Away Special Experimenter's Symposium

    NASA Technical Reports Server (NTRS)

    Barthelme, Neal (Editor); Mosier, Frances L. (Editor)

    1988-01-01

    The 1987 Get Away Special (GAS) Experimenter's symposium provides a formal opportunity for GAS Experimenter's to share the results of their projects. The focus of this symposium was on payloads that were flown on Shuttle missions, and on GAS payloads that will be flown in the future.

  20. An Artificial Experimenter for Enzymatic Response Characterisation

    NASA Astrophysics Data System (ADS)

    Lovell, Chris; Jones, Gareth; Gunn, Steve R.; Zauner, Klaus-Peter

    Identifying the characteristics of biological systems through physical experimentation, is restricted by the resources available, which are limited in comparison to the size of the parameter spaces being investigated. New tools are required to assist scientists in the effective characterisation of such behaviours. By combining artificial intelligence techniques for active experiment selection, with a microfluidic experimentation platform that reduces the volumes of reactants required per experiment, a fully autonomous experimentation machine is in development to assist biological response characterisation. Part of this machine, an artificial experimenter, has been designed that automatically proposes hypotheses, then determines experiments to test those hypotheses and explore the parameter space. Using a multiple hypotheses approach that allows for representative models of response behaviours to be produced with few observations, the artificial experimenter has been employed in a laboratory setting, where it selected experiments for a human scientist to perform, to investigate the optical absorbance properties of NADH.

  1. Experimental chaos detection in the Duffing oscillator

    NASA Astrophysics Data System (ADS)

    Eyebe Fouda, J. S. Armand; Bodo, Bertrand; Djeufa, Guy M. D.; Sabat, Samrat L.

    2016-04-01

    This paper presents a comparative study of four algorithms namely the maximal Lyapunov exponent (MLE), 0-1 test, conditional entropy of ordinal patterns (CPE) and recently developed permutation largest slope entropy (PLSE) algorithm for experimental chaos detection in the Duffing oscillator. We consider an electrical model of the Duffing oscillator and its equivalent electronic circuit for generating the data to validate the effectiveness of the algorithms. The performance of the PLSE is compared with the 0-1 test and the CPE algorithms on the data set obtained from the simulated circuit; and with the MLE for the data collected from the experimental circuit. The experimental data are acquired using a digital oscilloscope with 1 MHz sampling frequency. From the comparison of the experimental spectra of the four methods with the analog phase portraits of the real system, it appears that the PLSE is the more reliable algorithm for chaos detection from experimental data.

  2. Experimental Monte Carlo Quantum Process Certification

    NASA Astrophysics Data System (ADS)

    Steffen, L.; da Silva, M. P.; Fedorov, A.; Baur, M.; Wallraff, A.

    2012-06-01

    Experimental implementations of quantum information processing have now reached a level of sophistication where quantum process tomography is impractical. The number of experimental settings as well as the computational cost of the data postprocessing now translates to days of effort to characterize even experiments with as few as 8 qubits. Recently a more practical approach to determine the fidelity of an experimental quantum process has been proposed, where the experimental data are compared directly with an ideal process using Monte Carlo sampling. Here, we present an experimental implementation of this scheme in a circuit quantum electrodynamics setup to determine the fidelity of 2-qubit gates, such as the CPHASE and the CNOT gate, and 3-qubit gates, such as the Toffoli gate and two sequential CPHASE gates.

  3. Mainstreaming Caenorhabditis elegans in experimental evolution.

    PubMed

    Gray, Jeremy C; Cutter, Asher D

    2014-03-01

    Experimental evolution provides a powerful manipulative tool for probing evolutionary process and mechanism. As this approach to hypothesis testing has taken purchase in biology, so too has the number of experimental systems that use it, each with its own unique strengths and weaknesses. The depth of biological knowledge about Caenorhabditis nematodes, combined with their laboratory tractability, positions them well for exploiting experimental evolution in animal systems to understand deep questions in evolution and ecology, as well as in molecular genetics and systems biology. To date, Caenorhabditis elegans and related species have proved themselves in experimental evolution studies of the process of mutation, host-pathogen coevolution, mating system evolution and life-history theory. Yet these organisms are not broadly recognized for their utility for evolution experiments and remain underexploited. Here, we outline this experimental evolution work undertaken so far in Caenorhabditis, detail simple methodological tricks that can be exploited and identify research areas that are ripe for future discovery.

  4. Gaseous Sulfate Solubility in Glass: Experimental Method

    SciTech Connect

    Bliss, Mary

    2013-11-30

    Sulfate solubility in glass is a key parameter in many commercial glasses and nuclear waste glasses. This report summarizes key publications specific to sulfate solubility experimental methods and the underlying physical chemistry calculations. The published methods and experimental data are used to verify the calculations in this report and are expanded to a range of current technical interest. The calculations and experimental methods described in this report will guide several experiments on sulfate solubility and saturation for the Hanford Waste Treatment Plant Enhanced Waste Glass Models effort. There are several tables of sulfate gas equilibrium values at high temperature to guide experimental gas mixing and to achieve desired SO3 levels. This report also describes the necessary equipment and best practices to perform sulfate saturation experiments for molten glasses. Results and findings will be published when experimental work is finished and this report is validated from the data obtained.

  5. Experimental model updating using frequency response functions

    NASA Astrophysics Data System (ADS)

    Hong, Yu; Liu, Xi; Dong, Xinjun; Wang, Yang; Pu, Qianhui

    2016-04-01

    In order to obtain a finite element (FE) model that can more accurately describe structural behaviors, experimental data measured from the actual structure can be used to update the FE model. The process is known as FE model updating. In this paper, a frequency response function (FRF)-based model updating approach is presented. The approach attempts to minimize the difference between analytical and experimental FRFs, while the experimental FRFs are calculated using simultaneously measured dynamic excitation and corresponding structural responses. In this study, the FRF-based model updating method is validated through laboratory experiments on a four-story shear-frame structure. To obtain the experimental FRFs, shake table tests and impact hammer tests are performed. The FRF-based model updating method is shown to successfully update the stiffness, mass and damping parameters of the four-story structure, so that the analytical and experimental FRFs match well with each other.

  6. CO(2)-triggered chloride release from guard cells in intact fava bean leaves. Kinetics of the onset of stomatal closure.

    PubMed

    Hanstein, Stefan M; Felle, Hubert H

    2002-10-01

    The influence of CO(2) on Cl(-) release from guard cells was investigated within the intact leaf by monitoring the Cl(-) activity in the apoplastic fluid of guard cells with a Cl(-)-sensitive microelectrode. In illuminated leaves adapted to a CO(2) concentration within the cuvette of 350 microL L(-1), an increase of 250 microL L(-1) CO(2) triggered a transient rise in the apoplastic Cl(-) activity from 3 to 14 mM within 10 min. This Cl(-) response was similar to the Cl(-) efflux evoked by turning off the light, when the substomatal CO(2) was kept constant (CO(2) clamp). Without CO(2) clamp, substomatal CO(2) increased by 120 microL L(-1) upon "light off." The response to an increase in CO(2) within the cuvette from 250 to 500 microL L(-1) in dark-adapted leaves was equivalent to the response to an increase from 350 to 600 microL L(-1) in the light. No Cl(-) efflux was triggered by 2-min CO(2) pulses (150-800 microL L(-1)). After a switch from 350 microL L(-1) to CO(2)-free cuvette air, the guard cells were less sensitive to a rise in CO(2) and to light off, but the sensitivity to both stimuli partially recovered. Changes in CO(2) also caused changes of the guard cell apoplastic voltage, which were generally faster than the observed Cl(-) responses, and which also promptly occurred when CO(2) did not initiate Cl(-) efflux. The comparatively slow activation of Cl(-) efflux by CO(2) indicates that an intermediate effector derived from CO(2) has to accumulate to fully activate plasma membrane anion channels of guard cells.

  7. A histochemical study of protein-bound SH and SS in chromosomes of hyacinth and fava bean root tips.

    PubMed

    Wiese, D A

    1980-01-01

    Root tips were fixed in ethanol-acetic acid and in neutral formalin containing a mercaptide-forming agent to protect thiols from autoxidation. Serial paraffin sections 2 micrometers thick were labelled for thiols, disulfides and both together with the azogenic maleimide 'APM'. Nuclei were stained somewhat lighter for thiols, and nucleoli much darker, than was the surrounding cytoplasm; disulfide staining was paler and more evenly distributed. However, regardless of the fixative employed, mitotic chromosomes (precisely localized by fluorescent Feulgen counterstaining) contained negligible amounts of either thiols or disulfides. Although published biochemical studies also have indicated low concentrations of cyst(e)inyl residues in chromosomal proteins, the present findings contradict most previous histochemical reports.

  8. pCyP B: a chloroplast-localized, heat shock-responsive cyclophilin from fava bean.

    PubMed

    Luan, S; Lane, W S; Schreiber, S L

    1994-06-01

    When the immunosuppressants cyclosporin A (CsA) and FK506 bind to their intracellular receptors (immunophillins), they form complexes that bind to calcineurin and block calcineurin-dependent signaling pathways in immune cells. Previously, we reported that higher plants also express immunophilins and have a Ca(2+)-dependent signaling pathway sensitive to immunophilin-ligand complexes. Based on an N-terminal peptide sequence of a chloroplast-localized cyclophilin (pCyP B), we isolated a cDNA clone encoding the preprotein of the cyclophilin. The deduced amino acid sequence of this cDNA starts with a putative transit sequence for chloroplast targeting. The mature pCyP B protein has rotamase activity with low-substrate specificity. Enzyme activity was inhibited by CsA with an inhibition constant of 3.9 nM. Similar to other CyPs from mammalian cells, pCyP B, when complexed with CsA, inhibited the phosphatase activity of bovine calcineurin. The mRNA level of pCyP B was high in leaf tissue but was not detectable in roots. Expression of the transcript in the leaf tissues was regulated by light and induced by heat shock. These findings illustrate the conserved nature of cyclophilin proteins among all of the eukaryotes and suggest that cyclophilins have a unique mode of regulation in higher plants.

  9. A histochemical study of protein-bound SH and SS in chromosomes of hyacinth and fava bean root tips.

    PubMed

    Wiese, D A

    1980-01-01

    Root tips were fixed in ethanol-acetic acid and in neutral formalin containing a mercaptide-forming agent to protect thiols from autoxidation. Serial paraffin sections 2 micrometers thick were labelled for thiols, disulfides and both together with the azogenic maleimide 'APM'. Nuclei were stained somewhat lighter for thiols, and nucleoli much darker, than was the surrounding cytoplasm; disulfide staining was paler and more evenly distributed. However, regardless of the fixative employed, mitotic chromosomes (precisely localized by fluorescent Feulgen counterstaining) contained negligible amounts of either thiols or disulfides. Although published biochemical studies also have indicated low concentrations of cyst(e)inyl residues in chromosomal proteins, the present findings contradict most previous histochemical reports. PMID:7462011

  10. pCyP B: a chloroplast-localized, heat shock-responsive cyclophilin from fava bean.

    PubMed

    Luan, S; Lane, W S; Schreiber, S L

    1994-06-01

    When the immunosuppressants cyclosporin A (CsA) and FK506 bind to their intracellular receptors (immunophillins), they form complexes that bind to calcineurin and block calcineurin-dependent signaling pathways in immune cells. Previously, we reported that higher plants also express immunophilins and have a Ca(2+)-dependent signaling pathway sensitive to immunophilin-ligand complexes. Based on an N-terminal peptide sequence of a chloroplast-localized cyclophilin (pCyP B), we isolated a cDNA clone encoding the preprotein of the cyclophilin. The deduced amino acid sequence of this cDNA starts with a putative transit sequence for chloroplast targeting. The mature pCyP B protein has rotamase activity with low-substrate specificity. Enzyme activity was inhibited by CsA with an inhibition constant of 3.9 nM. Similar to other CyPs from mammalian cells, pCyP B, when complexed with CsA, inhibited the phosphatase activity of bovine calcineurin. The mRNA level of pCyP B was high in leaf tissue but was not detectable in roots. Expression of the transcript in the leaf tissues was regulated by light and induced by heat shock. These findings illustrate the conserved nature of cyclophilin proteins among all of the eukaryotes and suggest that cyclophilins have a unique mode of regulation in higher plants. PMID:8061522

  11. CO(2)-triggered chloride release from guard cells in intact fava bean leaves. Kinetics of the onset of stomatal closure.

    PubMed

    Hanstein, Stefan M; Felle, Hubert H

    2002-10-01

    The influence of CO(2) on Cl(-) release from guard cells was investigated within the intact leaf by monitoring the Cl(-) activity in the apoplastic fluid of guard cells with a Cl(-)-sensitive microelectrode. In illuminated leaves adapted to a CO(2) concentration within the cuvette of 350 microL L(-1), an increase of 250 microL L(-1) CO(2) triggered a transient rise in the apoplastic Cl(-) activity from 3 to 14 mM within 10 min. This Cl(-) response was similar to the Cl(-) efflux evoked by turning off the light, when the substomatal CO(2) was kept constant (CO(2) clamp). Without CO(2) clamp, substomatal CO(2) increased by 120 microL L(-1) upon "light off." The response to an increase in CO(2) within the cuvette from 250 to 500 microL L(-1) in dark-adapted leaves was equivalent to the response to an increase from 350 to 600 microL L(-1) in the light. No Cl(-) efflux was triggered by 2-min CO(2) pulses (150-800 microL L(-1)). After a switch from 350 microL L(-1) to CO(2)-free cuvette air, the guard cells were less sensitive to a rise in CO(2) and to light off, but the sensitivity to both stimuli partially recovered. Changes in CO(2) also caused changes of the guard cell apoplastic voltage, which were generally faster than the observed Cl(-) responses, and which also promptly occurred when CO(2) did not initiate Cl(-) efflux. The comparatively slow activation of Cl(-) efflux by CO(2) indicates that an intermediate effector derived from CO(2) has to accumulate to fully activate plasma membrane anion channels of guard cells. PMID:12376658

  12. Physical and Mathematical Modeling in Experimental Papers.

    PubMed

    Möbius, Wolfram; Laan, Liedewij

    2015-12-17

    An increasing number of publications include modeling. Often, such studies help us to gain a deeper insight into the phenomena studied and break down barriers between experimental and theoretical communities. However, combining experimental and theoretical work is challenging for authors, reviewers, and readers. To help maximize the usefulness and impact of combined theoretical and experimental research, this Primer describes the purpose, usefulness, and different types of models and addresses the practical aspect of integrated publications by outlining characteristics of good modeling, presentation, and fruitful collaborations.

  13. EXFOR Library of Experimental Nuclear Reaction Data

    DOE Data Explorer

    The EXFOR library contains an extensive compilation of experimental nuclear reaction data up to 1 GeV. Neutron reactions have been compiled systematically since the discovery of the neutron, while charged particle(up to carbon) and photon reactions have been covered less extensively. Files contain nuclear reaction data such as cross sections, spectra, angular distributions, polarizations, etc, along with information on experimental technique, error analysis, and applied standards. Numerous search parameters include: target, beam, product, experimental method, and even author and publication names. The library contains data from more than 20,000 experiments. (Specialized Interface)

  14. Drought Adaptation Mechanisms Should Guide Experimental Design.

    PubMed

    Gilbert, Matthew E; Medina, Viviana

    2016-08-01

    The mechanism, or hypothesis, of how a plant might be adapted to drought should strongly influence experimental design. For instance, an experiment testing for water conservation should be distinct from a damage-tolerance evaluation. We define here four new, general mechanisms for plant adaptation to drought such that experiments can be more easily designed based upon the definitions. A series of experimental methods are suggested together with appropriate physiological measurements related to the drought adaptation mechanisms. The suggestion is made that the experimental manipulation should match the rate, length, and severity of soil water deficit (SWD) necessary to test the hypothesized type of drought adaptation mechanism. PMID:27090148

  15. Experimental economics' inconsistent ban on deception.

    PubMed

    Hersch, Gil

    2015-08-01

    According to what I call the 'argument from public bads', if a researcher deceived subjects in the past, there is a chance that subjects will discount the information that a subsequent researcher provides, thus compromising the validity of the subsequent researcher's experiment. While this argument is taken to justify an existing informal ban on explicit deception in experimental economics, it can also apply to implicit deception, yet implicit deception is not banned and is sometimes used in experimental economics. Thus, experimental economists are being inconsistent when they appeal to the argument from public bads to justify banning explicit deception but not implicit deception.

  16. An experimental analysis of human straight walking

    NASA Astrophysics Data System (ADS)

    Li, Tao; Ceccarelli, Marco

    2013-03-01

    In this paper, an experimental analysis of human straight walking has been presented. Experiments on human walking were carried out by using Cassino tracking system which is a passive cable-based measuring system. This system is adopted because it is capable of both pose and wrench measurements with fairly simple monitoring of operation. By using experimental results, trajectories of a human limb extremity and its posture have been analyzed; forces that are exerted against cables by the limb of a person under test have been measured by force sensors as well. Furthermore, by using experimental tests, modeling and characterization of the human straight walking gait have been proposed.

  17. Physical and Mathematical Modeling in Experimental Papers.

    PubMed

    Möbius, Wolfram; Laan, Liedewij

    2015-12-17

    An increasing number of publications include modeling. Often, such studies help us to gain a deeper insight into the phenomena studied and break down barriers between experimental and theoretical communities. However, combining experimental and theoretical work is challenging for authors, reviewers, and readers. To help maximize the usefulness and impact of combined theoretical and experimental research, this Primer describes the purpose, usefulness, and different types of models and addresses the practical aspect of integrated publications by outlining characteristics of good modeling, presentation, and fruitful collaborations. PMID:26687351

  18. Depressed mood and smoking experimentation among preteens.

    PubMed

    Polen, Michael R; Curry, Susan J; Grothaus, Louis C; Bush, Terry M; Hollis, Jack F; Ludman, Evette J; McAfee, Timothy A

    2004-06-01

    The authors examined children's depressed mood, parental depressed mood, and parental smoking in relation to children's smoking susceptibility and experimentation over 20 months in a cohort of 418 preteens (ages 10-12 at baseline) and their parents. Depressed mood in preteens was strongly related to experimentation but not to susceptibility. In cross-sectional analyses parental depressed mood was related to children's experimentation, but in longitudinal analyses parental depressed mood at baseline did not differentiate children who experimented from those who did not. Although parental smoking was strongly related to experimentation, it was not related to susceptibility either cross-sectionally or longitudinally. Depressed mood among preteens and parents appeared to be more strongly related to children's smoking behaviors than to their intentions to smoke. PMID:15238063

  19. Experimental evidence of the compressibility of arteries.

    PubMed

    Yosibash, Zohar; Manor, Itay; Gilad, Ilan; Willentz, Udi

    2014-11-01

    A definitive answer to the question whether artery walls are incompressible is to our opinion not yet categorically provided. Experimental-based evidence on the level of compressibility in artery walls is not easily achieved because of the difficulties associated with the measurement of very small differences in volumes under physiological pressure in these biological tissues. Past experiments aimed at addressing the question considered different species, different arteries, the experimental devices were not accurate enough and a statistical analysis of the results was missing. A precise experimental device together with a thorough testing protocol, a careful selection of arteries and a statistical analysis is presented for a definitive evaluation of the artery wall compressibility. We provide experimental evidence that in saphenous and femoral porcine arteries under physiological pressure range a relative compressibility of 2-6% is observed. The pre-assumption of incompressibility in many phenomenological constitutive models of artery walls should probably be re-evaluated.

  20. A Simple Approach to Experimental Errors

    ERIC Educational Resources Information Center

    Phillips, M. D.

    1972-01-01

    Classifies experimental error into two main groups: systematic error (instrument, personal, inherent, and variational errors) and random errors (reading and setting errors) and presents mathematical treatments for the determination of random errors. (PR)

  1. Joint Actinide Shock Physics Experimental Research - JASPER

    ScienceCinema

    None

    2016-07-12

    Commonly known as JASPER the Joint Actinide Shock Physics Experimental Research facility is a two stage light gas gun used to study the behavior of plutonium and other materials under high pressures, temperatures, and strain rates.

  2. Physics at hadron colliders: Experimental view

    SciTech Connect

    Siegrist, J.L.

    1987-08-01

    The physics of the hadron-hadron collider experiment is considered from an experimental point of view. The problems encountered in determination of how well the standard model describes collider results are discussed. 53 refs., 58 figs.

  3. Evapotranspiration studies for protective barriers: Experimental plans

    SciTech Connect

    Link, S.O.; Waugh, W.J.

    1989-11-01

    This document describes a general theory and experimental plans for predicting evapotranspiration in support of the Protective Barrier Program. Evapotranspiration is the combined loss of water from plants and soil surfaces to the atmosphere. 45 refs., 1 fig., 4 tabs.

  4. 50 CFR 665.17 - Experimental fishing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... EFP will be governed by 15 CFR part 904 subpart D. Other sanctions available under the statute will be... experimental fishing for crustacean MUS may be conducted unless a NMFS observer is aboard the vessel....

  5. 50 CFR 665.17 - Experimental fishing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... EFP will be governed by 15 CFR part 904 subpart D. Other sanctions available under the statute will be... experimental fishing for crustacean MUS may be conducted unless a NMFS observer is aboard the vessel....

  6. 50 CFR 665.17 - Experimental fishing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... EFP will be governed by 15 CFR part 904 subpart D. Other sanctions available under the statute will be... experimental fishing for crustacean MUS may be conducted unless a NMFS observer is aboard the vessel....

  7. 50 CFR 665.17 - Experimental fishing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... EFP will be governed by 15 CFR part 904 subpart D. Other sanctions available under the statute will be... experimental fishing for crustacean MUS may be conducted unless a NMFS observer is aboard the vessel....

  8. 50 CFR 665.17 - Experimental fishing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... EFP will be governed by 15 CFR part 904 subpart D. Other sanctions available under the statute will be... experimental fishing for crustacean MUS may be conducted unless a NMFS observer is aboard the vessel....

  9. Multiple sclerosis: Experimental and clinical aspects

    SciTech Connect

    Scheinberg, L.; Raine, C.S.

    1984-01-01

    This book discusses the experimental and clinical aspects of multiple sclerosis. Specifically discussed are - Association of Epstein Barr Virus with pathology of central nervous system; immunology of viruses; and immunosuppression.

  10. A Cognitive Approach to Experimental Amnesia

    ERIC Educational Resources Information Center

    Lewis, Donald J.

    1976-01-01

    A review of selected experiments indicates that not all examples of experimental amnesia are due to the failure of a memory to fixate. In sum, the empirical retrograde amnesia gradient does not necessarily support traditional consolidation theory. (Editor)

  11. Depressed mood and smoking experimentation among preteens.

    PubMed

    Polen, Michael R; Curry, Susan J; Grothaus, Louis C; Bush, Terry M; Hollis, Jack F; Ludman, Evette J; McAfee, Timothy A

    2004-06-01

    The authors examined children's depressed mood, parental depressed mood, and parental smoking in relation to children's smoking susceptibility and experimentation over 20 months in a cohort of 418 preteens (ages 10-12 at baseline) and their parents. Depressed mood in preteens was strongly related to experimentation but not to susceptibility. In cross-sectional analyses parental depressed mood was related to children's experimentation, but in longitudinal analyses parental depressed mood at baseline did not differentiate children who experimented from those who did not. Although parental smoking was strongly related to experimentation, it was not related to susceptibility either cross-sectionally or longitudinally. Depressed mood among preteens and parents appeared to be more strongly related to children's smoking behaviors than to their intentions to smoke.

  12. Joint Actinide Shock Physics Experimental Research - JASPER

    SciTech Connect

    2014-10-31

    Commonly known as JASPER the Joint Actinide Shock Physics Experimental Research facility is a two stage light gas gun used to study the behavior of plutonium and other materials under high pressures, temperatures, and strain rates.

  13. Yakima Hatchery Experimental Design : Annual Progress Report.

    SciTech Connect

    Busack, Craig; Knudsen, Curtis; Marshall, Anne

    1991-08-01

    This progress report details the results and status of Washington Department of Fisheries' (WDF) pre-facility monitoring, research, and evaluation efforts, through May 1991, designed to support the development of an Experimental Design Plan (EDP) for the Yakima/Klickitat Fisheries Project (YKFP), previously termed the Yakima/Klickitat Production Project (YKPP or Y/KPP). This pre- facility work has been guided by planning efforts of various research and quality control teams of the project that are annually captured as revisions to the experimental design and pre-facility work plans. The current objective are as follows: to develop genetic monitoring and evaluation approach for the Y/KPP; to evaluate stock identification monitoring tools, approaches, and opportunities available to meet specific objectives of the experimental plan; and to evaluate adult and juvenile enumeration and sampling/collection capabilities in the Y/KPP necessary to measure experimental response variables.

  14. Experimental Evidence of Chaos from Memristors

    NASA Astrophysics Data System (ADS)

    Gambuzza, Lucia Valentina; Fortuna, Luigi; Frasca, Mattia; Gale, Ella

    Until now, most memristor-based chaotic circuits proposed in the literature are based on mathematical models which assume ideal characteristics such as piecewise-linear or cubic nonlinearities. The idea, illustrated here and originating from the experimental approach for device characterization, is to realize a chaotic system exploiting the nonlinearity of only one memristor with a very simple experimental set-up using feedback. In this way, a simple circuit is obtained and chaos is experimentally observed and is confirmed by the calculation of the largest Lyapunov exponent. Numerical results using the Strukov model support the existence of robust chaos in our circuit. To our knowledge, this is the first experimental demonstration of chaos in a real memristor circuit and suggests that memristors are well placed for hardware encryption.

  15. Experimental design of a waste glass study

    SciTech Connect

    Piepel, G.F.; Redgate, P.E.; Hrma, P.

    1995-04-01

    A Composition Variation Study (CVS) is being performed to support a future high-level waste glass plant at Hanford. A total of 147 glasses, covering a broad region of compositions melting at approximately 1150{degrees}C, were tested in five statistically designed experimental phases. This paper focuses on the goals, strategies, and techniques used in designing the five phases. The overall strategy was to investigate glass compositions on the boundary and interior of an experimental region defined by single- component, multiple-component, and property constraints. Statistical optimal experimental design techniques were used to cover various subregions of the experimental region in each phase. Empirical mixture models for glass properties (as functions of glass composition) from previous phases wee used in designing subsequent CVS phases.

  16. Experimental study and evaluation of radioprotective drugs

    NASA Technical Reports Server (NTRS)

    Smith, D. E.; Thomson, J. F.

    1968-01-01

    Experimental study evaluates radioprotective drugs administered before exposure either orally or intravenously. Specifically studied are the sources of radiation, choice of radiation dose, choice of animals, administration of drugs, the toxicity of protective agents and types of protective drug.

  17. Experimental studies of weakly coupled superconductors (Review)

    NASA Astrophysics Data System (ADS)

    Dmitrenko, I. M.

    2004-07-01

    A review is given of the main experimental results obtained in research on weakly coupled superconductors after 1964 at the Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine, Kharkov (ILTPE).

  18. Experimental Garden Plots for Botany Lessons

    ERIC Educational Resources Information Center

    Gorodnicheva, V. V.; Vasil'eva, E. I.

    1976-01-01

    Discussion of the botany lessons used at two schools points out the need for fifth and sixth grade students to be taught the principles of plant life through observations made at an experimental garden plot at the school. (ND)

  19. Experimental Investigations of Flow past Spinning Cylinders

    NASA Astrophysics Data System (ADS)

    Carlucci, Pasquale; Buckley, Liam; Mehmedagic, Igbal; Carlucci, Donald; Thangam, Siva

    2015-11-01

    Experimental investigations of flow past spinning cylinders is presented in the context of their application and relevance to flow past projectiles. A subsonic wind tunnel is used to perform experiments on flow past spinning cylinders that are sting-mounted and oriented such that their axis of rotation is aligned with the mean flow. The experiments cover a Reynolds number range of up to 300000 and rotation numbers of up to 2 (based on cylinder diameter). The experimental validation of the tunnel characteristics and the benchmarking of the flow field in the tunnel are described. The experimental results for spinning cylinders with both rear-mounted and fore-mounted stings are presented along with available computational and experimental findings. This work was funded in part by U. S. Army ARDEC.

  20. Experimental design methods for bioengineering applications.

    PubMed

    Keskin Gündoğdu, Tuğba; Deniz, İrem; Çalışkan, Gülizar; Şahin, Erdem Sefa; Azbar, Nuri

    2016-01-01

    Experimental design is a form of process analysis in which certain factors are selected to obtain the desired responses of interest. It may also be used for the determination of the effects of various independent factors on a dependent factor. The bioengineering discipline includes many different areas of scientific interest, and each study area is affected and governed by many different factors. Briefly analyzing the important factors and selecting an experimental design for optimization are very effective tools for the design of any bioprocess under question. This review summarizes experimental design methods that can be used to investigate various factors relating to bioengineering processes. The experimental methods generally used in bioengineering are as follows: full factorial design, fractional factorial design, Plackett-Burman design, Taguchi design, Box-Behnken design and central composite design. These design methods are briefly introduced, and then the application of these design methods to study different bioengineering processes is analyzed.

  1. Efficiency wages in an experimental labor market.

    PubMed

    Rigdon, Mary L

    2002-10-01

    There has been recent experimental support for efficiency wage theories of the labor market. This short paper initiates the larger process of evaluating the boundary conditions of the gift- exchange phenomenon. In particular, we will see whether behavior consistent with the fair wage-effort hypothesis can emerge and be sustained under conditions in which there is (i) a nontrivial marginal cost to providing effort and (ii) increased social distance between subject and experimenter. PMID:16578880

  2. An experimental study on microwave electron gun

    SciTech Connect

    Wang, G.; Wu, J.; Wang, Y.

    1995-12-31

    We report both the simulation and experimental results of using a ring cathode instead of the solid cathode to reduce the back bombardment effect of a thermionic cathode microwave electron gun. The result shows that the back bombardment power is decreased about 2/3 without changing the beam quality apparently which allows operation at higher repetition rate. Experimental results are compared with the simulation with good agreement.

  3. New experimental techniques for solar cells

    NASA Technical Reports Server (NTRS)

    Lenk, R.

    1993-01-01

    Solar cell capacitance has special importance for an array controlled by shunting. Experimental measurements of solar cell capacitance in the past have shown disagreements of orders of magnitude. Correct measurement technique depends on maintaining the excitation voltage less than the thermal voltage. Two different experimental methods are shown to match theory well, and two effective capacitances are defined for quantifying the effect of the solar cell capacitance on the shunting system.

  4. Flutter Calculations for an Experimental Fan

    NASA Technical Reports Server (NTRS)

    Bakhle, Milind A.; Srivastava, Rakesh; Panovsky, Josef; Keith, Theo G., Jr.; Stefko, George L.

    2003-01-01

    During testing, an experimental forward-swept fan encountered flutter at part-speed conditions. A three-dimensional propulsion aeroelasticity code, based on a computational fluid dynamics (CFD) approach, was used to model the aeroelastic behavior of this fan. This paper describes the flutter calculations and compares the results to the experimental measurements. Results of sensitivity studies are also presented that show the relative importance of different aspects of aeroelastic modeling.

  5. An Experimental Analysis of Another Privacy

    ERIC Educational Resources Information Center

    Okouchi, Hiroto

    2006-01-01

    The present article discusses how events outside a subject's skin and not accessible to another subject but to an experimenter may contribute to experimental analyses of private events. Of 16 undergraduates, 8, referred to as instructors, first learned conditional discriminations (i.e., B1C1, B2C2, B3C3, and B4C4) in a standard matching-to-sample…

  6. Experimental verification of Cerenkov line radiation

    SciTech Connect

    Xu, K.; Bing-xin Yang; Fu-yun Xi; Wei-ming Wu; Lu-yan Hao

    1988-04-15

    An experimental study of Cerenkov line radiation is reviewed. The Cerenkov line radiation is emitted in a gas by electrons from a /sup 90/Sr ..beta.. source and measured by a coincidence technique. Its major characteristics were studied experimentally. It is discovered that the radiation has a line spectrum, its angular distribution is obviously anisotropic, it is plane polarized, and it has a short emitting time.

  7. Relation between experimental and non-experimental study designs. HB vaccines: a case study

    PubMed Central

    Jefferson, T.; Demicheli, V.

    1999-01-01

    STUDY OBJECTIVE: To examine the relation between experimental and non- experimental study design in vaccinology. DESIGN: Assessment of each study design's capability of testing four aspects of vaccine performance, namely immunogenicity (the capacity to stimulate the immune system), duration of immunity conferred, incidence and seriousness of side effects, and number of infections prevented by vaccination. SETTING: Experimental and non-experimental studies on hepatitis B (HB) vaccines in the Cochrane Vaccines Field Database. RESULTS: Experimental and non-experimental vaccine study designs are frequently complementary but some aspects of vaccine quality can only be assessed by one of the types of study. More work needs to be done on the relation between study quality and its significance in terms of effect size.   PMID:10326054

  8. Using experimental design to define boundary manikins.

    PubMed

    Bertilsson, Erik; Högberg, Dan; Hanson, Lars

    2012-01-01

    When evaluating human-machine interaction it is central to consider anthropometric diversity to ensure intended accommodation levels. A well-known method is the use of boundary cases where manikins with extreme but likely measurement combinations are derived by mathematical treatment of anthropometric data. The supposition by that method is that the use of these manikins will facilitate accommodation of the expected part of the total, less extreme, population. In literature sources there are differences in how many and in what way these manikins should be defined. A similar field to the boundary case method is the use of experimental design in where relationships between affecting factors of a process is studied by a systematic approach. This paper examines the possibilities to adopt methodology used in experimental design to define a group of manikins. Different experimental designs were adopted to be used together with a confidence region and its axes. The result from the study shows that it is possible to adapt the methodology of experimental design when creating groups of manikins. The size of these groups of manikins depends heavily on the number of key measurements but also on the type of chosen experimental design. PMID:22317428

  9. Evaluation of an experimental dental porcelain.

    PubMed

    Hamouda, Ibrahim M; El-Waseffy, Noha A; Hasan, Ahmed M; El-Falal, Abeer A

    2010-11-01

    The aim of this study was to evaluate fracture toughness, hardness, ceramic/metal bond strength and microstructure of experimental dental porcelain and compare it with commercial type. Specimens of specific dimensions were prepared. Fracture toughness was assessed by a three-point bending test. The Vickers hardness was measured using a microhardness tester. The ceramometal bond strength was measured using a universal testing machine. The load was applied at the porcelain/metal interface via a chisel edged blade with a crosshead speed of 2.0 mm/min until fracture. The polished specimens of dental porcelain were chemically etched and the microstructure was analyzed with a scanning electron microscope. The results showed comparable fracture toughness and bond strength for both materials, while the experimental porcelain exhibited higher hardness. The experimental porcelain showed uniform cohesive failure while the commercial type showed mixed mode of failure. The microstructure of the experimental porcelain was tetragonal leucite crystals dispersed randomly in a glass matrix. The leucite crystals exist in two forms, acicular and rod like structures. It was concluded that the experimental porcelain has adequate fracture toughness and ceramic/metal bond strength that can resist the rapid crack propagation and its consequent catastrophic failure, which indicates a material serviceability in the oral cavity.

  10. [Experimentation with women: science fiction or reality?].

    PubMed

    Villar Amigó, Vicente M

    2008-01-01

    Many people will not have heard about the experimentation that has been, and continues to be, carried out on women, because much of the media makes no mention of the matter. Just a few examples that could be mentioned are experimentation with the contraceptive pill, forced sterilization, egg donation, surrogate motherhood, kidney and other organ donation, and unnecessary therapy and surgery. In a few cases such experimentation could well be termed exploitation of women, with all kinds of excuses or humanitarian reasons, and sometimes communitarian purposes and even reasons concerning possible benefits for the whole of society, being mentioned. The present work aims to stimulate reflection about some types of research which can only be regarded as exploitation of women.

  11. Optimal Experimental Design for Model Discrimination

    PubMed Central

    Myung, Jay I.; Pitt, Mark A.

    2009-01-01

    Models of a psychological process can be difficult to discriminate experimentally because it is not easy to determine the values of the critical design variables (e.g., presentation schedule, stimulus structure) that will be most informative in differentiating them. Recent developments in sampling-based search methods in statistics make it possible to determine these values, and thereby identify an optimal experimental design. After describing the method, it is demonstrated in two content areas in cognitive psychology in which models are highly competitive: retention (i.e., forgetting) and categorization. The optimal design is compared with the quality of designs used in the literature. The findings demonstrate that design optimization has the potential to increase the informativeness of the experimental method. PMID:19618983

  12. Combustion experimentation aboard the space transportation system

    NASA Technical Reports Server (NTRS)

    Dewitt, R. L.

    1981-01-01

    A description is presented of the preliminary concept, specifications, and general requirements of a proposed Combustion Facility (CF) for the Spacelab payload of the Space Transportation System. The CF will permit an experimenter to use suitably contained liquid, gas, or solid fuels. He can specify and establish the composition and pressure level of the atmosphere in which the combustion will take place. It will be possible to characterize the experiment with common types of instrumentation as well as selected specialized equipment, to study the combustion process visually by direct observation and by motion picture coverage, and to obtain time histories of pertinent experimental parameters. During an experimental period, the CF will depend on Spacelab resources for power, heat rejection, and vacuum. Activating the CF and preparing it for the various experiments, performing the experiments, and shutting down the facility will be largely manual operations performed by flight personnel.

  13. An experimental aluminum-fueled power plant

    NASA Astrophysics Data System (ADS)

    Vlaskin, M. S.; Shkolnikov, E. I.; Bersh, A. V.; Zhuk, A. Z.; Lisicyn, A. V.; Sorokovikov, A. I.; Pankina, Yu. V.

    2011-10-01

    An experimental co-generation power plant (CGPP-10) using aluminum micron powder (with average particle size up to 70 μm) as primary fuel and water as primary oxidant was developed and tested. Power plant can work in autonomous (unconnected from industrial network) nonstop regime producing hydrogen, electrical energy and heat. One of the key components of experimental plant is aluminum-water high-pressure reactor projected for hydrogen production rate of ∼10 nm3 h-1. Hydrogen from the reactor goes through condenser and dehumidifier and with -25 °C dew-point temperature enters into the air-hydrogen fuel cell 16 kW-battery. From 1 kg of aluminum the experimental plant produces 1 kWh of electrical energy and 5-7 kWh of heat. Power consumer gets about 10 kW of electrical power. Plant electrical and total efficiencies are 12% and 72%, respectively.

  14. Modern Experimental Techniques in Turbine Engine Testing

    NASA Technical Reports Server (NTRS)

    Lepicovsky, J.; Bruckner, R. J.; Bencic, T. J.; Braunscheidel, E. P.

    1996-01-01

    The paper describes application of two modern experimental techniques, thin-film thermocouples and pressure sensitive paint, to measurement in turbine engine components. A growing trend of using computational codes in turbomachinery design and development requires experimental techniques to refocus from overall performance testing to acquisition of detailed data on flow and heat transfer physics to validate these codes for design applications. The discussed experimental techniques satisfy this shift in focus. Both techniques are nonintrusive in practical terms. The thin-film thermocouple technique improves accuracy of surface temperature and heat transfer measurements. The pressure sensitive paint technique supplies areal surface pressure data rather than discrete point values only. The paper summarizes our experience with these techniques and suggests improvements to ease the application of these techniques for future turbomachinery research and code verifications.

  15. Experimental bound entanglement through a Pauli channel

    PubMed Central

    Amselem, Elias; Sadiq, Muhammad; Bourennane, Mohamed

    2013-01-01

    Understanding the characteristics of a quantum systems when affected by noise is one of the biggest challenges for quantum technologies. The general Pauli error channel is an important lossless channel for quantum communication. In this work we consider the effects of a Pauli channel on a pure four-qubit state and simulate the Pauli channel experimentally by studying the action on polarization encoded entangled photons. When the noise channel acting on the photons is correlated, a set spanned by four orthogonal bound entangled states can be generated. We study this interesting case experimentally and demonstrate that products of Bell states can be brought into a bound entangled regime. We find states in the set of bound entangled states which experimentally violate the CHSH inequality while still possessing a positive partial transpose. PMID:23752651

  16. Modeling biomedical experimental processes with OBI

    PubMed Central

    2010-01-01

    Background Experimental descriptions are typically stored as free text without using standardized terminology, creating challenges in comparison, reproduction and analysis. These difficulties impose limitations on data exchange and information retrieval. Results The Ontology for Biomedical Investigations (OBI), developed as a global, cross-community effort, provides a resource that represents biomedical investigations in an explicit and integrative framework. Here we detail three real-world applications of OBI, provide detailed modeling information and explain how to use OBI. Conclusion We demonstrate how OBI can be applied to different biomedical investigations to both facilitate interpretation of the experimental process and increase the computational processing and integration within the Semantic Web. The logical definitions of the entities involved allow computers to unambiguously understand and integrate different biological experimental processes and their relevant components. Availability OBI is available at http://purl.obolibrary.org/obo/obi/2009-11-02/obi.owl PMID:20626927

  17. Experimental demonstration of spinor slow light

    NASA Astrophysics Data System (ADS)

    Lee, Meng-Jung; Ruseckas, Julius; Lee, Chin-Yuan; Kudriašov, Viačeslav; Chang, Kao-Fang; Cho, Hung-Wen; JuzeliÅ«nas, Gediminas; Yu, Ite A.

    2016-03-01

    Over the last decade there has been a continuing interest in slow and stored light based on the electromagnetically induced transparency (EIT) effect, because of their potential applications in quantum information manipulation. However, previous experimental works all dealt with the single-component slow light which cannot be employed as a qubit. In this work, we report the first experimental demonstration of two-component or spinor slow light (SSL) using a double tripod (DT) atom-light coupling scheme. The oscillations between the two components, similar to the Rabi oscillation of a two-level system or a qubit, were observed. Single-photon SSL can be considered as two-color qubits. We experimentally demonstrated a possible application of the DT scheme as quantum memory and quantum rotator for the two-color qubits. This work opens up a new direction in the slow light research.

  18. Achieving optimal SERS through enhanced experimental design

    PubMed Central

    Fisk, Heidi; Westley, Chloe; Turner, Nicholas J.

    2016-01-01

    One of the current limitations surrounding surface‐enhanced Raman scattering (SERS) is the perceived lack of reproducibility. SERS is indeed challenging, and for analyte detection, it is vital that the analyte interacts with the metal surface. However, as this is analyte dependent, there is not a single set of SERS conditions that are universal. This means that experimental optimisation for optimum SERS response is vital. Most researchers optimise one factor at a time, where a single parameter is altered first before going onto optimise the next. This is a very inefficient way of searching the experimental landscape. In this review, we explore the use of more powerful multivariate approaches to SERS experimental optimisation based on design of experiments and evolutionary computational methods. We particularly focus on colloidal‐based SERS rather than thin film preparations as a result of their popularity. © 2015 The Authors. Journal of Raman Spectroscopy published by John Wiley & Sons, Ltd. PMID:27587905

  19. Experimental quantum fingerprinting with weak coherent pulses.

    PubMed

    Xu, Feihu; Arrazola, Juan Miguel; Wei, Kejin; Wang, Wenyuan; Palacios-Avila, Pablo; Feng, Chen; Sajeed, Shihan; Lütkenhaus, Norbert; Lo, Hoi-Kwong

    2015-10-30

    Quantum communication holds the promise of creating disruptive technologies that will play an essential role in future communication networks. For example, the study of quantum communication complexity has shown that quantum communication allows exponential reductions in the information that must be transmitted to solve distributed computational tasks. Recently, protocols that realize this advantage using optical implementations have been proposed. Here we report a proof-of-concept experimental demonstration of a quantum fingerprinting system that is capable of transmitting less information than the best-known classical protocol. Our implementation is based on a modified version of a commercial quantum key distribution system using off-the-shelf optical components over telecom wavelengths, and is practical for messages as large as 100 Mbits, even in the presence of experimental imperfections. Our results provide a first step in the development of experimental quantum communication complexity.

  20. Experimental quantum fingerprinting with weak coherent pulses

    PubMed Central

    Xu, Feihu; Arrazola, Juan Miguel; Wei, Kejin; Wang, Wenyuan; Palacios-Avila, Pablo; Feng, Chen; Sajeed, Shihan; Lütkenhaus, Norbert; Lo, Hoi-Kwong

    2015-01-01

    Quantum communication holds the promise of creating disruptive technologies that will play an essential role in future communication networks. For example, the study of quantum communication complexity has shown that quantum communication allows exponential reductions in the information that must be transmitted to solve distributed computational tasks. Recently, protocols that realize this advantage using optical implementations have been proposed. Here we report a proof-of-concept experimental demonstration of a quantum fingerprinting system that is capable of transmitting less information than the best-known classical protocol. Our implementation is based on a modified version of a commercial quantum key distribution system using off-the-shelf optical components over telecom wavelengths, and is practical for messages as large as 100 Mbits, even in the presence of experimental imperfections. Our results provide a first step in the development of experimental quantum communication complexity. PMID:26515586

  1. Immune reactions and allergy in experimental anisakiasis

    PubMed Central

    Lee, Haneul Nari

    2006-01-01

    The third-stage larvae (L3) of the parasitic nematode, Anisakis simplex, have been implicated in the induction of hyperimmune allergic reactions in orally infected humans. In this work, we have conducted a review of an investigation into immune reactions occurring in animals experimentally infected with A. simplex L3. The patterns of serum antibody productions in the experimental animals against excretory-secretory products (ESP) of A. simplex L3 contributed to our current knowledge regarding specific humoral immune reactions in humans. In our review, we were able to determine that L3 infection of experimental animals may constitute a good model system for further exploration of immune mechanisms and allergy in anisakiasis of humans. PMID:17170569

  2. Experimental characterization of composites. [load test methods

    NASA Technical Reports Server (NTRS)

    Bert, C. W.

    1975-01-01

    The experimental characterization for composite materials is generally more complicated than for ordinary homogeneous, isotropic materials because composites behave in a much more complex fashion, due to macroscopic anisotropic effects and lamination effects. Problems concerning the static uniaxial tension test for composite materials are considered along with approaches for conducting static uniaxial compression tests and static uniaxial bending tests. Studies of static shear properties are discussed, taking into account in-plane shear, twisting shear, and thickness shear. Attention is given to static multiaxial loading, systematized experimental programs for the complete characterization of static properties, and dynamic properties.

  3. Computatonal and experimental study of laminar flames

    SciTech Connect

    Smooke, M.D.; Long, M.B.

    1993-12-01

    This research has centered on an investigation of the effects of complex chemistry and detailed transport on the structure and extinction of hydrocarbon flames in counterflow, cylindrical and coflowing axisymmetric configurations. The authors have pursued both computational and experimental aspects of the research in parallel. The computational work has focused on the application of accurate and efficient numerical methods for the solution of the one and two-dimensional nonlinear boundary value problems describing the various reacting systems. Detailed experimental measurements were performed on axisymmetric coflow flames using two-dimensional imaging techniques. In particular, spontaneous Raman scattering and laser induced fluorescence were used to measure the temperature, major and minor species profiles.

  4. Experimental evidence for Abraham pressure of light

    NASA Astrophysics Data System (ADS)

    Zhang, Li; She, Weilong; Peng, Nan; Leonhardt, Ulf

    2015-05-01

    The question of how much momentum light carries in media has been debated for over a century. Two rivalling theories, one from 1908 by Hermann Minkowski and the other from 1909 by Max Abraham, predict the exact opposite when light enters an optical material: a pulling force in Minkowski's case and a pushing force in Abraham's. Most experimental tests have agreed with Minkowski's theory, but here we report the first quantitative experimental evidence for Abraham's pushing pressure of light. Our results matter in optofluidics and optomechanics, and wherever light exerts mechanical pressure.

  5. Conceptual design of Fusion Experimental Reactor

    NASA Astrophysics Data System (ADS)

    Seki, Yasushi; Takatsu, Hideyuki; Iida, Hiromasa

    1991-08-01

    Safety analysis and evaluation have been made for the FER (Fusion Experimental Reactor) as well as for the ITER (International Thermonuclear Experimental Reactor) which are basically the same in terms of safety. This report describes the results obtained in fiscal years 1988 - 1990, in addition to a summary of the results obtained prior to 1988. The report shows the philosophy of the safety design, safety analysis and evaluation for each of the operation conditions, namely, normal operation, repair and maintenance, and accident. Considerations for safety regulations and standards are also added.

  6. Experimental and Modeling Studies of Massif Anorthosites

    NASA Technical Reports Server (NTRS)

    Longhi, John

    1999-01-01

    This termination report covers the latter part of a single research effort spanning several grant cycles. During this time there was a single title, "Experimental and Modeling Studies of Massif Anorthosites", but there were several contract numbers as the mode and location of NASA contract administration changed. Initially, the project was funded as an increment to the PI's other grant, "Early Differentiation of the Moon: Experimental and Modeling Studies", but subsequently it became an independent grant. Table 1 contains a brief summary of the dates and contract numbers.

  7. Experimental validation of VESTA 2.1

    NASA Astrophysics Data System (ADS)

    Haeck, W.; Cochet, B.; Bernard, F.; Tymen, A.

    2014-06-01

    Depletion codes such as VESTA are used to calculate the evolution of a material subjected to radiation (be it neutrons or another type of particle) for a wide variety of applications in the fields of nuclear safety, radiation protection and environmental health safety. For these applications, experimental validation is paramount. In this paper we will describe the experimental validation of the latest version of VESTA using a set of 76 samples consisting of radiochemical assay data and decay heat measurements. We will describe the general calculation procedure that has been applied to determine the uncertainty on each individual nuclide measurement as well as the general tendencies and detailed results.

  8. First Experimental Realization of the Dirac Oscillator

    NASA Astrophysics Data System (ADS)

    Franco-Villafañe, J. A.; Sadurní, E.; Barkhofen, S.; Kuhl, U.; Mortessagne, F.; Seligman, T. H.

    2013-10-01

    We present the first experimental microwave realization of the one-dimensional Dirac oscillator, a paradigm in exactly solvable relativistic systems. The experiment relies on a relation of the Dirac oscillator to a corresponding tight-binding system. This tight-binding system is implemented as a microwave system by a chain of coupled dielectric disks, where the coupling is evanescent and can be adjusted appropriately. The resonances of the finite microwave system yield the spectrum of the one-dimensional Dirac oscillator with and without a mass term. The flexibility of the experimental setup allows the implementation of other one-dimensional Dirac-type equations.

  9. Experimental measurement-device-independent entanglement detection.

    PubMed

    Nawareg, Mohamed; Muhammad, Sadiq; Amselem, Elias; Bourennane, Mohamed

    2015-01-01

    Entanglement is one of the most puzzling features of quantum theory and of great importance for the new field of quantum information. The determination whether a given state is entangled or not is one of the most challenging open problems of the field. Here we report on the experimental demonstration of measurement-device-independent (MDI) entanglement detection using witness method for general two qubits photon polarization systems. In the MDI settings, there is no requirement to assume perfect implementations or neither to trust the measurement devices. This experimental demonstration can be generalized for the investigation of properties of quantum systems and for the realization of cryptography and communication protocols. PMID:25649664

  10. Tandem mirror thermal barrier experimental program plan

    SciTech Connect

    Coensgen, F.H.; Drake, R.P.; Simonen, T.C.

    1980-01-02

    This report describes an experimental plan for the development of the Tandem Mirror Thermal Barrier. Included is: (1) a description of thermal barrier related physics experiments; (2) thermal barrier related experiments in the existing TMX and Phaedrus experiments; (3) a thermal barrier TMX upgrade; and (4) initiation of investigations of axisymmetric magnetic geometry. Experimental studies of the first two items are presently underway. Results are expected from the TMX upgrade by the close of 1981 and from axisymmetric tandem mirror experiments at the end of 1983. Plans for Phaedrus upgrades are developing for the same period.

  11. Experimental study of uncentralized squeeze film dampers

    NASA Technical Reports Server (NTRS)

    Quinn, R. D.

    1983-01-01

    The vibration response of a rotor system supported by a squeeze film damper (SFD) was experimentally investigated in order to provide experimental data in support of the Rotor/Stator Interactive Finite Element theoretical development. Part of the investigation required the designing and building of a rotor/SFD system that could operate with or without end seals in order to accommodate different SFD lengths. SFD variables investigated included clearance, eccentricity mass, fluid pressure, and viscosity and temperature. The results show inlet pressure, viscosity and clearance have significant influence on the damper performance and accompanying rotor response.

  12. Macrophages and Uveitis in Experimental Animal Models

    PubMed Central

    Mérida, Salvador; Palacios, Elena; Bosch-Morell, Francisco

    2015-01-01

    Resident and infiltrated macrophages play relevant roles in uveitis as effectors of innate immunity and inductors of acquired immunity. They are major effectors of tissue damage in uveitis and are also considered to be potent antigen-presenting cells. In the last few years, experimental animal models of uveitis have enabled us to enhance our understanding of the leading role of macrophages in eye inflammation processes, including macrophage polarization in experimental autoimmune uveoretinitis and the major role of Toll-like receptor 4 in endotoxin-induced uveitis. This improved knowledge should guide advantageous iterative research to establish mechanisms and possible therapeutic targets for human uveitis resolution. PMID:26078494

  13. Modelling from the experimental developmental biologists viewpoint.

    PubMed

    Economou, Andrew D; Green, Jeremy B A

    2014-11-01

    In this review we consider Reaction-Diffusion as the archetype of a model in developmental biology. We consider its history in relation to experimental work since it was first proposed in 1952 by Turing and revived in the 1970s by Meinhardt. We then discuss the most recent examples of experiments that address this model, including the challenges that remain in capturing the physico-chemical manifestation of the model mechanism in a real developmental system. Finally we discuss the model's current status and use in the experimental community. PMID:25026465

  14. Therapeutic effects of sofalcone on experimental gastritis.

    PubMed

    Kishimoto, S; Okamoto, K; Kambara, A; Kajiyama, G; Miyoshi, A; Suwa, T

    1987-08-01

    A study was made on the therapeutic effects of sofalcone (SU-88), an antiulcer agent, on erosive and atrophic gastritis induced experimentally by 6-month administration of 5 mmol/l of sodium taurocholate (TCA) in rats. A standard meal including sofalcone of 0.25% and 1.0% shortened the total length of erosions, normalized the mucosal thickness, and reduced collagenous fibers in the gastric mucosa in one month. The doses administered were 116.3 mg and 486.1 mg/kg/week for one month. Sofalcone, thus, had a good therapeutic effect on experimental erosive and atrophic gastritis in rats. PMID:3675690

  15. Conceptual design report, CEBAF basic experimental equipment

    SciTech Connect

    1990-04-13

    The Continuous Electron Beam Accelerator Facility (CEBAF) will be dedicated to basic research in Nuclear Physics using electrons and photons as projectiles. The accelerator configuration allows three nearly continuous beams to be delivered simultaneously in three experimental halls, which will be equipped with complementary sets of instruments: Hall A--two high resolution magnetic spectrometers; Hall B--a large acceptance magnetic spectrometer; Hall C--a high-momentum, moderate resolution, magnetic spectrometer and a variety of more dedicated instruments. This report contains a short description of the initial complement of experimental equipment to be installed in each of the three halls.

  16. Didactic Objects for Development of Young Children's Combinatorial Experimentation and Causal-Experimental Thought

    ERIC Educational Resources Information Center

    Poddiakov, Alexander

    2011-01-01

    Combinatorial abilities are fundamental to experimental thinking. The aim of this work was to design didactic objects that will stimulate preschoolers' experimental thinking and to study young children's thinking in relation to these objects. Six heuristic rules for the design of didactic objects are specified, and the responses of 623 children…

  17. Experimental Methodology in English Teaching and Learning: Method Features, Validity Issues, and Embedded Experimental Design

    ERIC Educational Resources Information Center

    Lee, Jang Ho

    2012-01-01

    Experimental methods have played a significant role in the growth of English teaching and learning studies. The paper presented here outlines basic features of experimental design, including the manipulation of independent variables, the role and practicality of randomised controlled trials (RCTs) in educational research, and alternative methods…

  18. Students' Epistemologies about Experimental Physics: Validating the Colorado Learning Attitudes about Science Survey for Experimental Physics

    ERIC Educational Resources Information Center

    Wilcox, Bethany R.; Lewandowski, H. J.

    2016-01-01

    Student learning in instructional physics labs represents a growing area of research that includes investigations of students' beliefs and expectations about the nature of experimental physics. To directly probe students' epistemologies about experimental physics and support broader lab transformation efforts at the University of Colorado Boulder…

  19. Reconciling Experimental and Quasi-Experimental Evidence on the Impact of Full-Day Kindergarten

    ERIC Educational Resources Information Center

    Gibbs, Chloe

    2013-01-01

    This paper addresses the question of how to interpret evidence on the impact of full-day kindergarten resulting from different study designs, and provides guidance on how this evidence taken in tandem may inform the design and implementation of full-day kindergarten policies. Incorporating both experimental and quasi-experimental estimates on…

  20. Children's Understanding of Experimental Contrast and Experimental Control: An Inventory for Primary School

    ERIC Educational Resources Information Center

    Osterhaus, Christopher; Koerber, Susanne; Sodian, Beate

    2015-01-01

    Experimentation skills are a central component of scientific thinking, and many studies have investigated whether and when primary-school children develop adequate experimentation strategies. However, the answers to these questions vary substantially depending on the type of task that is used: while discovery tasks, which require children to…

  1. Experimental Evolution of Antibiotic Resistance in Bacteria

    ERIC Educational Resources Information Center

    Krist, Amy C.; Showsh, Sasha A.

    2007-01-01

    Evolution is typically measured as a change in allele or genotype frequencies over one or more generations. Consequently, evolution is difficult to show experimentally in a semester-long lab course because most organisms have longer generation times than 15 weeks. In this article, the authors present an experiment to demonstrate and study…

  2. Modeling and experimental investigating loop heat pipes

    SciTech Connect

    Kiseev, V.M.; Pogorelov, N.P.; Nouroutdinov, V.A.

    1995-12-31

    Design variants of two-phase systems of thermal control with heat flux inversion and experimental data are presented. Simplified functional dependence of heat flux for loop heat pipes with heat flux inversion versus effective pore radius of capillary structures under various external conditions are obtained.

  3. Essays on Experimental Economics and Education

    ERIC Educational Resources Information Center

    Ogawa, Scott Richard

    2013-01-01

    In Chapter 1 I consider three separate explanations for how price affects the usage rate of a purchased product: Screening, signaling, and sunk-cost bias. I propose an experimental design that disentangles the three effects. Furthermore, in order to quantify and compare these effects I introduce a simple structural model and show that the…

  4. Drosophila Melanogaster as an Experimental Organism.

    ERIC Educational Resources Information Center

    Rubin, Gerald M.

    1988-01-01

    Discusses the role of the fruit fly in genetics research requiring a multidisciplinary approach. Describes embryological and genetic methods used in the experimental analysis of this organism. Outlines the use of Drosophila in the study of the development and function of the nervous system. (RT)

  5. Growing Plants Without Soil for Experimental Use.

    ERIC Educational Resources Information Center

    Blankendaal, M.; And Others

    Much of the current research in experimental plant biology requires highly uniform plants. To achieve this, many plants are grown under conditions in which the environment is carefully manipulated. This pamphlet has been prepared, therefore, to present and describe growth procedures which will produce vigorous, healthy, uniform plant material in…

  6. Experimental Stream Facility: Design and Research

    EPA Science Inventory

    The Experimental Stream Facility (ESF) is a valuable research tool for the U.S. Environmental Protection Agency’s (EPA) Office of Research and Development’s (ORD) laboratories in Cincinnati, Ohio. This brochure describes the ESF, which is one of only a handful of research facilit...

  7. Experimental interstellar organic chemistry - Preliminary findings

    NASA Technical Reports Server (NTRS)

    Khare, B. N.; Sagan, C.

    1973-01-01

    Review of the results of some explicit experimental simulation of interstellar organic chemistry consisting in low-temperature high-vacuum UV irradiation of condensed simple gases known or suspected to be present in the interstellar medium. The results include the finding that acetonitrile may be present in the interstellar medium. The implication of this and other findings are discussed.

  8. Experimental Demonstrations in Teaching Chemical Reactions.

    ERIC Educational Resources Information Center

    Hugerat, Muhamad; Basheer, Sobhi

    2001-01-01

    Presents demonstrations of chemical reactions by employing different features of various compounds that can be altered after a chemical change occurs. Experimental activities include para- and dia-magnetism in chemical reactions, aluminum reaction with base, reaction of acid with carbonates, use of electrochemical cells for demonstrating chemical…

  9. Simulation as an Aid to Experimental Design.

    ERIC Educational Resources Information Center

    Frazer, Jack W.; And Others

    1983-01-01

    Discusses simulation program to aid in the design of enzyme kinetic experimentation (includes sample runs). Concentration versus time profiles of any subset or all nine states of reactions can be displayed with/without simulated instrumental noise, allowing the user to estimate the practicality of any proposed experiment given known instrument…

  10. Comparing fluid mechanics models with experimental data.

    PubMed Central

    Spedding, G R

    2003-01-01

    The art of modelling the physical world lies in the appropriate simplification and abstraction of the complete problem. In fluid mechanics, the Navier-Stokes equations provide a model that is valid under most circumstances germane to animal locomotion, but the complexity of solutions provides strong incentive for the development of further, more simplified practical models. When the flow organizes itself so that all shearing motions are collected into localized patches, then various mathematical vortex models have been very successful in predicting and furthering the physical understanding of many flows, particularly in aerodynamics. Experimental models have the significant added convenience that the fluid mechanics can be generated by a real fluid, not a model, provided the appropriate dimensionless groups have similar values. Then, analogous problems can be encountered in making intelligible but independent descriptions of the experimental results. Finally, model predictions and experimental results may be compared if, and only if, numerical estimates of the likely variations in the tested quantities are provided. Examples from recent experimental measurements of wakes behind a fixed wing and behind a bird in free flight are used to illustrate these principles. PMID:14561348

  11. Experimentally Evoking Nonbelieved Memories for Childhood Events

    ERIC Educational Resources Information Center

    Otgaar, Henry; Scoboria, Alan; Smeets, Tom

    2013-01-01

    We report on the 1st experimental elicitation of nonbelieved memories for childhood events in adults (Study 1) and children (Study 2) using a modified false memory implantation paradigm. Participants received true (trip to a theme park) and false (hot air balloon ride) narratives and recalled these events during 2 interviews. After debriefing, 13%…

  12. Using Experimental Methods in Higher Education Research

    ERIC Educational Resources Information Center

    Ross, Steven M.; Morrison, Gary R.; Lowther, Deborah L.

    2005-01-01

    Experimental methods have been used extensively for many years to conduct research in education and psychology. However, applications of experiments to investigate technology and other instructional innovations in higher education settings have been relatively limited. The present paper examines ways in which experiments can be used productively…

  13. GCFR shielding design and supporting experimental programs

    SciTech Connect

    Perkins, R.G.; Hamilton, C.J.; Bartine, D.

    1980-05-01

    The shielding for the conceptual design of the gas-cooled fast breeder reactor (GCFR) is described, and the component exposure design criteria which determine the shield design are presented. The experimental programs for validating the GCFR shielding design methods and data (which have been in existence since 1976) are also discussed.

  14. Yeast: An Experimental Organism for Modern Biology.

    ERIC Educational Resources Information Center

    Botstein, David; Fink, Gerald R.

    1988-01-01

    Discusses the applicability and advantages of using yeasts as popular and ideal model systems for studying and understanding eukaryotic biology at the cellular and molecular levels. Cites experimental tractability and the cooperative tradition of the research community of yeast biologists as reasons for this success. (RT)

  15. An Experimental Program in Leadership Preparation.

    ERIC Educational Resources Information Center

    Glasman, Naftaly S.

    1997-01-01

    Describes an experimental program in educational administration offered at the University of Judaism in Los Angeles, focusing on program implementation and evaluation. Provides a set of changes in a small leadership-training program. The program and its changes serve as models for adjustment in small leadership-preparation programs, particularly…

  16. The National Ignition Facility: Experimental Capability

    SciTech Connect

    Miller, G H

    2003-09-22

    The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory is a stadium-sized facility containing a 192-beam, 1.8-Megajoule, 500-Terawatt, ultraviolet laser system together with a 10-meter diameter target chamber with room for nearly 100 experimental diagnostics. NIF will be the world's largest and most energetic laser experimental system, providing a scientific center to study inertial confinement fusion and matter at extreme energy densities and pressures. NIF's energetic laser beams will compress fusion targets to conditions required for thermonuclear burn, liberating more energy than required to initiate the fusion reactions. Other NIF experiments will study physical processes at temperatures approaching 10{sup 8} K and 10{sup 11} bar, conditions that exist naturally only in the interior of stars, planets and in nuclear weapons. NIF has completed the first phases of its laser commissioning program. The first four beams of NIF have generated 106 kilojoules of infrared light and over 16 kJ at the third harmonic (351 nm). NIF's target experimental systems are being commissioned and experiments have begun. This paper discusses NIF's current and future experimental capability, plans for facility diagnostics, cryogenic target systems, specialized optics for experiments, and potential enhancements to NIF such as green laser operation and high-energy short pulse operation.

  17. Animal Experimentation: Issues for the 1980s.

    ERIC Educational Resources Information Center

    Zola, Judith C.; And Others

    1984-01-01

    Examines the extent to which issues related to animal experimentation are in conflict and proposes choices that might least comprise them. These issues include animal well-being, human well-being, self-interest of science, scientific validity and responsibility, progress in biomedical and behavioral science, and the future quality of medical care.…

  18. Experimental evidence of quantum randomness incomputability

    SciTech Connect

    Calude, Cristian S.; Dinneen, Michael J.; Dumitrescu, Monica; Svozil, Karl

    2010-08-15

    In contrast with software-generated randomness (called pseudo-randomness), quantum randomness can be proven incomputable; that is, it is not exactly reproducible by any algorithm. We provide experimental evidence of incomputability--an asymptotic property--of quantum randomness by performing finite tests of randomness inspired by algorithmic information theory.

  19. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Experimental certificates. 21.191 Section 21.191 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT.... Participating in air races, including (for such participants) practicing for such air races and flying to...

  20. Transitional Employment Experimental Model (TEEM). Final Report.

    ERIC Educational Resources Information Center

    California State Personnel Board, Sacramento.

    The final report of the Transitional Employemnt Experimental Model (TEEM) Project, a research and development project providing a potential model for a large scale manpower absorption program in times of economic need, is presented. One major purpose of the project was to demonstrate the viability of providing suitable job placement for the…

  1. Optimal Experimental Design for Model Discrimination

    ERIC Educational Resources Information Center

    Myung, Jay I.; Pitt, Mark A.

    2009-01-01

    Models of a psychological process can be difficult to discriminate experimentally because it is not easy to determine the values of the critical design variables (e.g., presentation schedule, stimulus structure) that will be most informative in differentiating them. Recent developments in sampling-based search methods in statistics make it…

  2. Collective Experimentation: Lessons from the Field

    ERIC Educational Resources Information Center

    Misiko, M.

    2009-01-01

    The purpose of this paper is to document smallholder experiences during a participatory experimental initiative and draw useful lessons for field practitioners. The main methods used to collect data were participant observation, in-depth interviews among 40 farmers, and analyses of notes taken during participatory monitoring and evaluation. These…

  3. The water dimer I: Experimental characterization

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, Anamika; Cole, William T. S.; Saykally, Richard J.

    2015-07-01

    As the archetype of water hydrogen bonding, the water dimer has been studied extensively by both theory and experiment for nearly seven decades. In this article, we present a detailed chronological review of the experimental dimer studies and the insights into the complex nature of water and hydrogen bonding gained from them. A subsequent letter will review the corresponding theoretical advances.

  4. An experimental X band phased array

    NASA Astrophysics Data System (ADS)

    Rao, N. P. R.; Limaye, K. U.; Ramalingam, R. P.; Gangadharan, T. S.; Bhandopadhyay, G.; Deshpande, P. A.

    1983-10-01

    The details of an X band experimental 11 x 11 element Phased Array Antenna of phased lens configuration with a monopulse space feed developed at LRDE are presented. The studies carried and the results obtained on collimation, beam steering, pattern variation with scan, array operation in two-dimensional search, dedicated track and track while scan (TWS) are also given.

  5. Upper Washita River experimental watersheds: Sediment Database

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improving the scientific understanding of the effectiveness of watershed conservation practices and floodwater-retardation structures to control floods and soil erosion is one of the primary objectives for sediment studies in the upper Washita River Experimental Watersheds. This paper summarizes se...

  6. Evaluation and experimentation with duck management strategies

    USGS Publications Warehouse

    Nichols, J.D.; Johnson, F.A.

    1989-01-01

    Our knowledge of the effects of hunting regulations on duck populations has been based largely on retrospective studies of historical data. We have reached the limits of what can be learned in this way. Future knowledge gains will likely come about only through experimentation and adaptive management.

  7. The white SR spectrum experimental station

    NASA Astrophysics Data System (ADS)

    Ancharov, A. I.; Evdokov, O. V.; Tolochko, B. P.; Sukhorukov, A. V.; Baru, S. E.; Savinov, G. A.; Kosov, A. V.; Sheromov, M. A.; Sikka, S. K.; Momin, S. N.

    2000-06-01

    A new experimental station for working with white synchrotron radiation is described. Radiation from the bending magnet of the VEPP-4 storage ring is used. The station is destined for study of structures at high pressure by energy-dispersive and Laue diffraction methods.

  8. Experimental and computational study of thaumasite structure

    SciTech Connect

    Scholtzová, Eva; Kucková, Lenka; Kožíšek, Jozef; Pálková, Helena; Tunega, Daniel

    2014-05-01

    The structure of thaumasite has been studied experimentally by means of a single crystal X-ray diffraction and FTIR methods, and theoretically using density functional theory (DFT) method. Very good agreement was achieved between calculated and experimental structural parameters. In addition, calculations offered the refinement of the positions of the hydrogen atoms. The detailed analysis of the hydrogen bonds existing in the thaumasite structure has been performed. Several types of hydrogen bonds have been classified. The water molecules coordinating Ca{sup 2+} cation act as proton donors in moderate O-H···O hydrogen bonds formed with CO₃⁻²and SO₄⁻² anions. The multiple O-H···O hydrogen bonds exist among water molecules themselves. Finally, relatively weak hydrogen bonds form water molecules with the OH groups from the coordination sphere of the Si(OH)₆⁻² anion. Further, calculated vibrational spectrum allowed complete assignment of all vibrational modes which are not available from the experimental spectrum that has a complex structure with overlapped bands, especially below 1500 cm⁻¹. Highlights: • The thaumasite structure was studied experimentally and using DFT method. • We used DFT method for the refinement of the positions of hydrogen atoms. • A detailed analysis of the hydrogen bonds was done. • A complete assignment of all bands to particular types of vibrations was done.

  9. 27 CFR 40.232 - Experimental purposes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., such as their chemical content; (2) Use by producers of packaging machines to test the operation of... purposes in a factory. (d) Use outside factory. A manufacturer may remove tobacco products in bond for... § 40.183, a manufacturer who removes tobacco products in bond for experimental purposes outside...

  10. 27 CFR 40.232 - Experimental purposes.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., such as their chemical content; (2) Use by producers of packaging machines to test the operation of... purposes in a factory. (d) Use outside factory. A manufacturer may remove tobacco products in bond for... § 40.183, a manufacturer who removes tobacco products in bond for experimental purposes outside...

  11. 27 CFR 40.232 - Experimental purposes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., such as their chemical content; (2) Use by producers of packaging machines to test the operation of... purposes in a factory. (d) Use outside factory. A manufacturer may remove tobacco products in bond for... § 40.183, a manufacturer who removes tobacco products in bond for experimental purposes outside...

  12. 27 CFR 40.232 - Experimental purposes.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., such as their chemical content; (2) Use by producers of packaging machines to test the operation of... purposes in a factory. (d) Use outside factory. A manufacturer may remove tobacco products in bond for... § 40.183, a manufacturer who removes tobacco products in bond for experimental purposes outside...

  13. 27 CFR 40.232 - Experimental purposes.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., such as their chemical content; (2) Use by producers of packaging machines to test the operation of... purposes in a factory. (d) Use outside factory. A manufacturer may remove tobacco products in bond for... § 40.183, a manufacturer who removes tobacco products in bond for experimental purposes outside...

  14. Physical Science Laboratory Manual, Experimental Version.

    ERIC Educational Resources Information Center

    Cooperative General Science Project, Atlanta, GA.

    Provided are physical science laboratory experiments which have been developed and used as a part of an experimental one year undergraduate course in general science for non-science majors. The experiments cover a limited number of topics representative of the scientific enterprise. Some of the topics are pressure and buoyancy, heat, motion,…

  15. Experimental Results in DIS from Jefferson Laboratory

    SciTech Connect

    Sebastian Kuhn

    2009-10-01

    We are summarizing the experimental program of Jefferson Lab (Thomas Jefferson National Accelerator Facility in Newport News, VA) in deep inelastic electron scattering. We show recent results and discuss future plans for both the present 6 GeV era and the 12 GeV energy-upgraded facility.

  16. Experimental evolution in fungi: An untapped resource.

    PubMed

    Fisher, Kaitlin J; Lang, Gregory I

    2016-09-01

    Historically, evolutionary biology has been considered an observational science. Examining populations and inferring evolutionary histories mold evolutionary theories. In contrast, laboratory evolution experiments make use of the amenability of traditional model organisms to study fundamental processes underlying evolution in real time in simple, but well-controlled, environments. With advances in high-throughput biology and next generation sequencing, it is now possible to propagate hundreds of parallel populations over thousands of generations and to quantify precisely the frequencies of various mutations over time. Experimental evolution combines the ability to simultaneously monitor replicate populations with the power to vary individual parameters to test specific evolutionary hypotheses, something that is impractical or infeasible in natural populations. Many labs are now conducting laboratory evolution experiments in nearly all model systems including viruses, bacteria, yeast, nematodes, and fruit flies. Among these systems, fungi occupy a unique niche: with a short generation time, small compact genomes, and sexual cycles, fungi are a particularly valuable and largely untapped resource for propelling future growth in the field of experimental evolution. Here, we describe the current state of fungal experimental evolution and why fungi are uniquely positioned to answer many of the outstanding questions in the field. We also review which fungal species are most well suited for experimental evolution. PMID:27375178

  17. How experimental trial context affects perceptual categorization

    PubMed Central

    Palmeri, Thomas J.; Mack, Michael L.

    2015-01-01

    To understand object categorization, participants are tested in experiments often quite different from how people experience object categories in the real world. Learning and knowledge of categories is measured in discrete experimental trials, those trials may or may not provide feedback, trials appear one after another, after some fixed inter-trial interval, with hundreds of trials in a row, within experimental blocks with some structure dictated by the experimental design. In the real world, outside of certain educational and vocational contexts, opportunities to learn and use categories are intermixed over time with a whole multitude of intervening experiences. It is clear from any elementary understanding of human cognition that sequential effects matter, yet this understanding is often ignored, and categorization trials are often instead treated as independent events, immune to local trial context. In this perspective, we use some of our work to illustrate some of the consequences of the fact that categorization experiments have a particular trial structure. Experimental trial context can affect performance in category learning and categorization experiments in ways that can profoundly affect theoretical conclusions. PMID:25745412

  18. Experimental investigation of 4-dimensional superspace crystals

    SciTech Connect

    Rasing, T.; Janner, A.

    1983-09-01

    The symmetry of incommensurate crystals can be described by higher dimensional space groups in the so called superspace approach. The basic ideas are explained and used for showing that superspace groups provide an adequate frame for analyzing experimental results on incommensurate crystals.

  19. Multiple Drafts of Experimental Laboratory Reports.

    ERIC Educational Resources Information Center

    Sanford, James F.

    Students could gain considerable insight into the philosophy and methods of scientific experimentation if instructors adopted procedures based on an understanding of and respect for writing as a process. Laboratory courses in psychology offer such an opportunity. These courses usually involve a heavy workload for both students and faculty, for, in…

  20. SEVENTH YEAR MATHEMATICS, VOLUME 1, EXPERIMENTAL EDITION.

    ERIC Educational Resources Information Center

    Secondary School Mathematics Curriculum Improvement Study, New York, NY.

    THIS IS VOLUME 1 OF A THREE-VOLUME EXPERIMENTAL EDITION CONTAINING A SEQUENCE OF ENRICHED MATERIALS FOR SEVENTH-GRADE MATHEMATICS. THESE MATERIALS ARE DESIGNED FOR A PROGRAM OF INDIVIDUALIZED INSTRUCTION FOR THE ACCELERATED STUDENT OR FOR CLASSROOM PRESENTATION BY THE TEACHER. THE PRESENTATION OF THE MATERIAL IS IN SUCH A MANNER AS TO REFLECT…

  1. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Experimental certificates. 21.191 Section 21.191 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT.... Participating in air races, including (for such participants) practicing for such air races and flying to...

  2. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Experimental certificates. 21.191 Section 21.191 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT.... Participating in air races, including (for such participants) practicing for such air races and flying to...

  3. Florida Language Profile: Booklet A. Experimental Edition.

    ERIC Educational Resources Information Center

    Wolking, William D.; And Others

    Presented is the experimental edition of the Florida Language Profile-Part A materials booklet, which is designed to measure the cognitive and language skills of children in kindergarten and first grade. Contents include pictures related to concepts such as size and quantity, shape, position and direction, similarity and difference, telling time,…

  4. Reflections on Experimental Research in Medical Education

    ERIC Educational Resources Information Center

    Cook, David A.; Beckman, Thomas J.

    2010-01-01

    As medical education research advances, it is important that education researchers employ rigorous methods for conducting and reporting their investigations. In this article we discuss several important yet oft neglected issues in designing experimental research in education. First, randomization controls for only a subset of possible confounders.…

  5. An Experimental Investigation of Cognitive Defusion

    ERIC Educational Resources Information Center

    Pilecki, Brian C.; McKay, Dean

    2012-01-01

    The current study compared cognitive defusion with other strategies in reducing the impact of experimentally induced negative emotional states. Sixty-seven undergraduates were assigned to one of three conditions (cognitive defusion, thought suppression, or control) and instructed in standardized approaches relevant to each condition before viewing…

  6. Inspection procedures for experimental fuel production

    NASA Astrophysics Data System (ADS)

    Campsie, I. C.; Rattray, H. D.

    1988-04-01

    This paper describes the inspection procedures used in the development and manufacture of experimental fuel elements and their components. The examples quoted mainly apply to the PFR experimental fuel programme, although for well over a quarter of a century the procedures and techniques have been progressively developed and applied to the Magnox, SGHW, AGR, HTR, PFR and PWR fuel development programmes undertaken at the UKAEA's Springfields and Windscale Nuclear Power Development Laboratories. In contrast to production runs involving large numbers of standard components, experimental fuel is often assembled from components which, while they may look alike, may have design and material variations. Thus in addition to normal batching and bonding operations, great emphasis has to be placed on dimensional inspection, material testing and the individual identification of all items, thus maintaining traceability throughout all operations. The quality and performance of experimental items are often evaluated comparing pre- and post-test dimensional or NDT measurements. In the case of irradiation tests, several years can elapse between the measurements, therefore it is essential to ensure the reproducibility and compatibility of pre- and post-test measuring techniques and the traceability of all measured data and standards.

  7. The Pragmatics of Information Retrieval Experimentation, Revisited.

    ERIC Educational Resources Information Center

    Tague-Sutcliffe, Jean

    1992-01-01

    This overview of the research process for the novice information retrieval (IR) researcher provides guidance on selecting a research question, choosing the type of test, defining variables, developing or using databases, finding and processing queries, assigning treatments to experimental units, collecting and analyzing the data, and presenting…

  8. An Experimental Analysis of Reading Fluency

    ERIC Educational Resources Information Center

    Jones, Kevin M.; Wickstrom, Katherine F.; Noltemeyer, Amity L.; Brown, Shelaina M.; Schuka, Jeffrey R.; Therrien, William J.

    2009-01-01

    The experimental analysis of academic responding has emerged as one approach to strengthening decisions related to problem analysis and treatment design. This study provided an example of how both brief and extended assessments can be used within a data based, problem solving approach to addressing reading fluency concerns. For six children with…

  9. Brief Experimental Analysis of Early Reading Interventions

    ERIC Educational Resources Information Center

    Petursdottir, Anna-Lind; McMaster, Kristen; McComas, Jennifer J.; Bradfield, Tracy; Braganza, Viveca; Koch-McDonald, Julie; Rodriguez, Roxana; Scharf, Haley

    2009-01-01

    The purpose of this study was to investigate how brief experimental analyses (BEAs) could be used to identify effective interventions for Kindergartners (2 girls and 2 boys, 5 years and 7-10 months old) with low performance and/or growth slope in letter sound fluency (LSF). Interventions were tested within a multielement design with brief…

  10. Teaching Experimental Science: Enzymes and the Laboratory.

    ERIC Educational Resources Information Center

    Foster, John M.

    1989-01-01

    Hampshire College needed to create opportunities for advanced undergraduates to have extensive laboratory or field experience in experimental sciences. A general biochemistry course, taught almost entirely in the laboratory, is described. The focus of the course is enzymes as catalysts and as proteins. (MLW)

  11. Experimental Concepts for Testing Seismic Hazard Models

    NASA Astrophysics Data System (ADS)

    Marzocchi, W.; Jordan, T. H.

    2015-12-01

    Seismic hazard analysis is the primary interface through which useful information about earthquake rupture and wave propagation is delivered to society. To account for the randomness (aleatory variability) and limited knowledge (epistemic uncertainty) of these natural processes, seismologists must formulate and test hazard models using the concepts of probability. In this presentation, we will address the scientific objections that have been raised over the years against probabilistic seismic hazard analysis (PSHA). Owing to the paucity of observations, we must rely on expert opinion to quantify the epistemic uncertainties of PSHA models (e.g., in the weighting of individual models from logic-tree ensembles of plausible models). The main theoretical issue is a frequentist critique: subjectivity is immeasurable; ergo, PSHA models cannot be objectively tested against data; ergo, they are fundamentally unscientific. We have argued (PNAS, 111, 11973-11978) that the Bayesian subjectivity required for casting epistemic uncertainties can be bridged with the frequentist objectivity needed for pure significance testing through "experimental concepts." An experimental concept specifies collections of data, observed and not yet observed, that are judged to be exchangeable (i.e., with a joint distribution independent of the data ordering) when conditioned on a set of explanatory variables. We illustrate, through concrete examples, experimental concepts useful in the testing of PSHA models for ontological errors in the presence of aleatory variability and epistemic uncertainty. In particular, we describe experimental concepts that lead to exchangeable binary sequences that are statistically independent but not identically distributed, showing how the Bayesian concept of exchangeability generalizes the frequentist concept of experimental repeatability. We also address the issue of testing PSHA models using spatially correlated data.

  12. Traceds: An Experimental Trace Element Partitioning Database

    NASA Astrophysics Data System (ADS)

    Nielsen, R. L.; Ghiorso, M. S.

    2014-12-01

    The goal of this project, which is part of the EARTHCHEM initiative, is to compile the existing experimental trace element partitioning data, and to develop a transparent, accessible resource for the community. The primary goal of experimental trace element partitioning studies is to create a database that can be used to develop models of how trace elements behave in natural geochemical systems. The range of approaches as to how this is accomplished and how the data are reported differs dramatically from one system to another and one investigator to another. This provides serious challenges to the creation of a coherent database - and suggests the need for a standard format for data presentation and reporting. The driving force for this compilation is to provide community access to the complete database for trace element experiments. Our new effort includes all the published analytical results from experimental determinations. In compiling the data, we have set a minimum standard for the data to be included. The threshold criteria include: Experimental conditions (temperature, pressure, device, container, time, etc.) Major element composition of the phases Trace element analyses of the phases Data sources that did not report these minimum components were not included. The rationale for not including such data is that the degree of equilibration is unknown, and more important, no rigorous approach to modeling the behavior of trace elements is possible without a knowledge of the actual concentrations or the temperature and pressure of formation. The data are stored using a schema derived from that of the Library of Experimental Phase Relations (LEPR), modified to account for additional metadata, and restructured to permit multiple analytical entries for various element/technique/standard combinations. Our ultimate goal is to produce a database together with a flexible user interface that will be useful for experimentalists to set up their work and to build

  13. The Origin of Eucrites: An Experimental Perspective

    NASA Technical Reports Server (NTRS)

    Jones, J. H.; Mittlefehldt, David W.; Jurewicz, A. J. G.; Lauer, H. V., Jr.; Hanson, B. Z.; Paslick, C. R.; McKay, G. A.

    1996-01-01

    The origin of eucrites has been the subject of debate. At issue is whether high-Mg# eucrites such as Sioux County are primitive or evolved liquids. We believe that the problem of the origin of eucrites is essentially solved. Problems associated with the petrogenesis of other achondrite groups remain, but the eucrites, taken as a whole, seem to present a clear and understandable story that we will present using experiments, analyses, and calculations. The two traditional eucrite groupings, the partial melting trend a.k.a. Stannem trend) and the fractional crystallization trend (a.k.a. Nuevo Laredo trend) have both been reproduced experimentally. The partial melting trend culminates in Sioux County. Sioux County is also an acceptable starting point for the fractional crystallization trend. The implication of these experimental results is that it is extremely difficult to relate the eucrites to diogenites, a group of pyroxene cumulates that conceivably could have crystallized from eucrite parent magmas.

  14. In vitro experimental investigation of voice production

    PubMed Central

    Horáčcek, Jaromír; Brücker, Christoph; Becker, Stefan

    2012-01-01

    The process of human phonation involves a complex interaction between the physical domains of structural dynamics, fluid flow, and acoustic sound production and radiation. Given the high degree of nonlinearity of these processes, even small anatomical or physiological disturbances can significantly affect the voice signal. In the worst cases, patients can lose their voice and hence the normal mode of speech communication. To improve medical therapies and surgical techniques it is very important to understand better the physics of the human phonation process. Due to the limited experimental access to the human larynx, alternative strategies, including artificial vocal folds, have been developed. The following review gives an overview of experimental investigations of artificial vocal folds within the last 30 years. The models are sorted into three groups: static models, externally driven models, and self-oscillating models. The focus is on the different models of the human vocal folds and on the ways in which they have been applied. PMID:23181007

  15. "Experimental amnesia" induced by emotional items.

    PubMed

    Angelini, R; Capozzoli, F; Lepore, P; Grossi, D; Orsini, A

    1994-02-01

    Tulving described an effect of retrograde amnesia in a free-recall task of word lists, produced by inserting items having priority in recall. Other authors confirmed the amnesic effect without giving instructions for priority both in recall and in recognition tasks. The effect was explained by Tulving as a premature termination of encoding processes. The similarity between these experiments and the researches aimed at reproducing amnesia by emotional trauma led us to hypothesize that the two phenomena might be due to the same functional mechanisms. We have organized a free-recall task of word lists into which emotional items were inserted. Our aim was to verify whether with these experimental conditions Tulving's results would be reproduced. The obtained data show amnesic effects in free recall; nevertheless, they do not seem to confirm closely the experimental hypothesis. Lastly, changes in primacy and recency effects produced by emotional items are analyzed.

  16. Histochemical analysis of experimental granulomatous uveitis.

    PubMed

    Kristeva, M; Biswas, J; Pararajasegaram, G; Sevanian, A; Rao, N A

    1991-01-01

    We have previously demonstrated the effects of various inhibitors of arachidonic acid metabolism on experimental lens-induced granulomatous uveitis. In the present study, we investigated the effect of these same inhibitors on the expression of lysosomal enzymes at different stages of choroidal inflammation in experimental lens-induced granulomatous uveitis and compared this to the inflammation observed at each stage examined. Lysosomal enzymes such as acid phosphatase, beta-glucuronidase and succinate dehydrogenase are known to be liberated during the maturation of mononuclear phagocytes to epithelioid cell granulomas. Although animals treated with nordihydroguaiaretic acid showed less severe inflammation than did indomethacin-treated or control animals, none of these agents appeared to affect the expression of acid phosphatase and beta-glucuronidase, as determined histochemically. Succinate dehydrogenase could not be detected in any of the eyes examined, even though sections of liver and kidney from these same animals were positive for this enzyme.

  17. Mechanical diode: Comparing numerical and experimental characterizations

    SciTech Connect

    Sagartz, M.J.; Segalman, D.; Simmermacher, T.

    1998-02-01

    In this introductory work, joint compliance is studied in both a numerical and experimental setting. A simple bolted interface is used as the test article and compliance is measured for the joint in both compression and in tension. This simple interface is shown to exhibit a strong non-linearity near the transition from compression to tension (or vice-versa). Modeling issues pertaining to numerically solving for the compliance are addressed. It is shown that the model predictions, in spite of convergence being very sensitive to numerical artifacts of the interface model, are in good agreement with experimentally measured strains and joint compliances. The joint behavior is a mechanical analogy to a diode, i.e., in compression, the joint is very stiff, acting almost as a rigid link, while in tension the joint is relatively soft, acting as a spring.

  18. Description of Liquid Nitrogen Experimental Test Facility

    NASA Technical Reports Server (NTRS)

    Jurns, John M.; Jacobs, Richard E.; Saiyed, Naseem H.

    1991-01-01

    The Liquid Nitrogen Test Facility is a unique test facility for ground-based liquid nitrogen experimentation. The test rig consists of an insulated tank of approximately 12.5 cubic ft in volume, which is supplied with liquid nitrogen from a 300 gal dewar via a vacuum jacketed piping system. The test tank is fitted with pressure and temperature measuring instrumentation, and with two view ports which allow visual observation of test conditions. To demonstrate the capabilities of the facility, the initial test program is briefly described. The objective of the test program is to measure the condensation rate by injecting liquid nitrogen as a subcooled spray into the ullage of a tank 50 percent full of liquid nitrogen at saturated conditions. The condensation rate of the nitrogen vapor on the subcooled spray can be analytically modeled, and results validated and corrected by experimentally measuring the vapor condensation on liquid sprays.

  19. Helium release during shale deformation: Experimental validation

    NASA Astrophysics Data System (ADS)

    Bauer, Stephen J.; Gardner, W. Payton; Heath, Jason E.

    2016-07-01

    This work describes initial experimental results of helium tracer release monitoring during deformation of shale. Naturally occurring radiogenic 4He is present in high concentration in most shales. During rock deformation, accumulated helium could be released as fractures are created and new transport pathways are created. We present the results of an experimental study in which confined reservoir shale samples, cored parallel and perpendicular to bedding, which were initially saturated with helium to simulate reservoir conditions, are subjected to triaxial compressive deformation. During the deformation experiment, differential stress, axial, and radial strains are systematically tracked. Release of helium is dynamically measured using a helium mass spectrometer leak detector. Helium released during deformation is observable at the laboratory scale and the release is tightly coupled to the shale deformation. These first measurements of dynamic helium release from rocks undergoing deformation show that helium provides information on the evolution of microstructure as a function of changes in stress and strain.

  20. Experimental nuclear reaction data collection EXFOR

    SciTech Connect

    Semkova, V.; Otuka, N.; Simakov, S. P.; Zerkin, V.

    2011-07-01

    The International Network of Nuclear Reaction Data Centres (NRDC) constitutes a worldwide cooperation of 14 nuclear data centres. The main activity of the NRDC Network is collection and compilation of experimental nuclear reaction cross section data and the related bibliographic information in the EXFOR and CINDA databases as well as dissemination of nuclear reaction data and associated documentation to users. The database contains information and numerical data from more than about 19000 experiments consisting of more than 140000 datasets. EXFOR is kept up to date by constantly adding newly published experimental information. Tools developed for data dissemination utilise modern database technologies with fast online capabilities over the Internet. Users are provided with sophisticated search options, a user-friendly retrieval interface for downloading data in different formats, and additional output options such as improved data plotting capabilities. The present status of the EXFOR database will be presented together with the latest development for data access and retrieval. (authors)

  1. Experimental demonstration of water based tunable metasurface

    NASA Astrophysics Data System (ADS)

    Odit, Mikhail; Kapitanova, Polina; Andryieuski, Andrei; Belov, Pavel; Lavrinenko, Andrei V.

    2016-07-01

    A simple dynamically tunable metasurface (two-dimensional metamaterial) operating at microwave frequencies is developed and experimentally investigated. Conceptually, the simplicity of the approach is granted by reconfigurable properties of unit cells partially filled with distilled water. The transmission spectra of the metasurface for linear and circular polarizations of the incident wave were experimentally measured under the metasurface rotation around a horizontal axis. The changes in the transmission coefficient magnitude up to 8 dB at 1.25 GHz are reported while rotating the metasurface by the 90° angle. The proposed approach manifests the cheap and accessible route for the electromagnetic wave control in the microwave region with the help of metasurfaces.

  2. Experimental determination of the quark mixing angles

    SciTech Connect

    Castro, G.L. )

    1991-07-30

    This paper reviews the current status of the determination of the quark mixing angles {vert bar}V{sub qq{prime}}{vert bar}, where q = u,c; q{prime} = d,s,b. The authors consider essentially exclusive decay processes, taking into account the main sources of uncertainties, the available calculations of flavor symmetry breaking for hadronic matrix elements and the possibilities of improvement offered by new experimental results. In some cases the authors provide full expressions for {vert bar}V{sub qq{prime}}{vert bar} in terms of measurable decay properties, which can be useful for new experimental data. Finally, the authors discuss briefly the effects on the unitarity tests of the Cabibbo-Kobayashi-Maskawa matrix when the authors consider recent corrections to the determination of {vert bar}V {sub ud}{vert bar}.

  3. Improving the physiological realism of experimental models.

    PubMed

    Vinnakota, Kalyan C; Cha, Chae Y; Rorsman, Patrik; Balaban, Robert S; La Gerche, Andre; Wade-Martins, Richard; Beard, Daniel A; Jeneson, Jeroen A L

    2016-04-01

    The Virtual Physiological Human (VPH) project aims to develop integrative, explanatory and predictive computational models (C-Models) as numerical investigational tools to study disease, identify and design effective therapies and provide an in silico platform for drug screening. Ultimately, these models rely on the analysis and integration of experimental data. As such, the success of VPH depends on the availability of physiologically realistic experimental models (E-Models) of human organ function that can be parametrized to test the numerical models. Here, the current state of suitable E-models, ranging from in vitro non-human cell organelles to in vivo human organ systems, is discussed. Specifically, challenges and recent progress in improving the physiological realism of E-models that may benefit the VPH project are highlighted and discussed using examples from the field of research on cardiovascular disease, musculoskeletal disorders, diabetes and Parkinson's disease. PMID:27051507

  4. Public perceptions of animal experimentation across Europe.

    PubMed

    von Roten, Fabienne Crettaz

    2013-08-01

    The goal of this article is to map out public perceptions of animal experimentation in 28 European countries. Postulating cross-cultural differences, this study mixes country-level variables (from the Eurostat database) and individual-level variables (from Eurobarometer Science and Technology 2010). It is shown that experimentation on animals such as mice is generally accepted in European countries, but perceptions are divided on dogs and monkeys. Between 2005 and 2010, we observe globally a change of approval on dogs and monkeys, with a significant decrease in nine countries. Multilevel analysis results show differences at country level (related to a post-industrialism model) and at individual level (related to gender, age, education, proximity and perceptions of science and the environment). These results may have consequences for public perceptions of science and we call for more cross-cultural research on press coverage of animal research and on the level of public engagement of scientists doing animal research.

  5. Bioinspiration: applying mechanical design to experimental biology.

    PubMed

    Flammang, Brooke E; Porter, Marianne E

    2011-07-01

    The production of bioinspired and biomimetic constructs has fostered much collaboration between biologists and engineers, although the extent of biological accuracy employed in the designs produced has not always been a priority. Even the exact definitions of "bioinspired" and "biomimetic" differ among biologists, engineers, and industrial designers, leading to confusion regarding the level of integration and replication of biological principles and physiology. By any name, biologically-inspired mechanical constructs have become an increasingly important research tool in experimental biology, offering the opportunity to focus research by creating model organisms that can be easily manipulated to fill a desired parameter space of structural and functional repertoires. Innovative researchers with both biological and engineering backgrounds have found ways to use bioinspired models to explore the biomechanics of organisms from all kingdoms to answer a variety of different questions. Bringing together these biologists and engineers will hopefully result in an open discourse of techniques and fruitful collaborations for experimental and industrial endeavors.

  6. Shock unsteadiness creation and propagation: experimental analysis

    NASA Astrophysics Data System (ADS)

    Benay, R.; Alaphilippe, M.; Severac, N.

    2012-09-01

    The possibility of creating unsteady distortions of the tip shock by waves emitted from an aircraft is assessed experimentally. The model chosen is a cylindrical fore body equipped with a spike. This configuration is known for generating an important level of unsteadiness around the spike in supersonic regime. The wind tunnel Mach number is equal to 2. The experiments show that waves emitted from this source propagate along the tip shock and interact with it. It is then assessed that this interaction produces a periodic distortion of the shock that propagates to the external flow. Unsteady pressure sensors, high speed schlieren films, hot wire probing and laser Doppler velocimetry are used as complementary experimental means. The final result is a coherent representation of the complex mechanism of wave propagation that has been evidenced. The principle of creating unsteady shock deformation by onboard equipments could be examined as a possibly promising method of sonic boom control.

  7. Natural compounds as anticancer agents: Experimental evidence

    PubMed Central

    Wang, Jiao; Jiang, Yang-Fu

    2012-01-01

    Cancer prevention research has drawn much attention worldwide. It is believed that some types of cancer can be prevented by following a healthy life style. Cancer chemoprevention by either natural or synthetic agents is a promising route towards lowering cancer incidence. In recent years, the concept of cancer chemoprevention has evolved greatly. Experimental studies in animal models demonstrate that the reversal or suppression of premalignant lesions by chemopreventive agents is achievable. Natural occurring agents such as dietary phytochemicals, tea polyphenols and resveratrol show chemopreventive activity in animal models. Moreover, clinical trials for testing the safety and efficacy of a variety of natural agents in preventing or treating human malignancy have been ongoing. Here, we summarize experimental data on the chemopreventive or tumor suppressive effects of several natural compounds including curcumin, (-)-epigallocatechin-3-gallate, resveratrol, indole-3-carbinol, and vitamin D. PMID:24520533

  8. A hybrid approach to experimental control.

    PubMed

    Dixon, Peter

    2009-08-01

    In the present article, I describe a new, hybrid approach to experimental control that combines the best features of general-purpose programs and specific-experiment programs. First, experimental control objects are developed in an object-oriented programming environment. Then, an XML file is used to select and arrange those control objects in order to carry out an experiment. A wide range of experiments can be implemented by specifying the arrangement of the control objects in the XML file, while, at the same time, the set of control objects can be easily extended for more demanding applications. An overview of a system using this approach is provided, along with some examples. PMID:19587170

  9. Description of liquid nitrogen experimental test facility

    NASA Technical Reports Server (NTRS)

    Jurns, J. M.; Jacobs, R. E.; Saiyed, N. H.

    1992-01-01

    The Liquid Nitrogen Test Facility is a unique test facility for ground-based liquid nitrogen experimentation. The test rig consists of an insulated tank of approximately 12.5 cubic ft in volume, which is supplied with liquid nitrogen from a 300 gal dewar via a vacuum jacketed piping system. The test tank is fitted with pressure and temperature measuring instrumentation, and with two view ports which allow visual observation of test conditions. To demonstrate the capabilities of the facility, the initial test program is briefly described. The objective of the test program is to measure the condensation rate by injecting liquid nitrogen as a subcooled spray into the ullage of a tank 50 percent full of liquid nitrogen at saturated conditions. The condensation rate of the nitrogen vapor on the subcooled spray can be analytically modeled, and results validated and corrected by experimentally measuring the vapor condensation on liquid sprays.

  10. Microwave radiometry for humanitarian demining: experimental results

    NASA Astrophysics Data System (ADS)

    Johnson, Joel T.; Kim, Hyunjin; Wiggins, David R.; Cheon, Yonghun

    2002-08-01

    Previous modeling studies have indicated that a multi-frequency radiometer could prove advantageous for humanitarian demining due to the oscillatory patterns in brightness temperature versus frequency that would be observed in the presence of a sub-surface target. Initial experimental results are reported in this paper from a multi-frequency radiometer (MFRAD) system operating at 19 frequencies in the 2.1-6.5 GHz band. The basic design of MFRAD is reviewed, and the calibration and noise background removal procedures discussed. Experimental results with sub-surface metallic and styrofoam targets are then provided that demonstrate the predicted oscillatory behavior. An FFT-based detection algorithm is also described and applied to measured data. Further plans for experiments and tests with this system are also detailed.

  11. Association between postmenopausal osteoporosis and experimental periodontitis.

    PubMed

    Luo, Kai; Ma, Souzhi; Guo, Jianbin; Huang, Yongling; Yan, Fuhua; Xiao, Yin

    2014-01-01

    To investigate the correlation between postmenopausal osteoporosis (PMO) and the pathogenesis of periodontitis, ovariectomized rats were generated and the experimental periodontitis was induced using a silk ligature. The inflammatory factors and bone metabolic markers were measured in the serum and periodontal tissues of ovariectomized rats using an automatic chemistry analyzer, enzyme-linked immunosorbent assays, and immunohistochemistry. The bone mineral density of whole body, pelvis, and spine was analyzed using dual-energy X-ray absorptiometry and image analysis. All data were analyzed using SPSS 13.0 statistical software. It was found that ovariectomy could upregulate the expression of interleukin- (IL-)6, the receptor activator of nuclear factor- κB ligand (RANKL), and osteoprotegerin (OPG) and downregulate IL-10 expression in periodontal tissues, which resulted in progressive alveolar bone loss in experimental periodontitis. This study indicates that changes of cytokines and bone turnover markers in the periodontal tissues of ovariectomized rats contribute to the damage of periodontal tissues.

  12. Experimental demonstration of composite adiabatic passage

    NASA Astrophysics Data System (ADS)

    Schraft, Daniel; Halfmann, Thomas; Genov, Genko T.; Vitanov, Nikolay V.

    2013-12-01

    We report an experimental demonstration of composite adiabatic passage (CAP) for robust and efficient manipulation of two-level systems. The technique represents a altered version of rapid adiabatic passage (RAP), driven by composite sequences of radiation pulses with appropriately chosen phases. We implement CAP with radio-frequency pulses to invert (i.e., to rephase) optically prepared spin coherences in a Pr3+:Y2SiO5 crystal. We perform systematic investigations of the efficiency of CAP and compare the results with conventional π pulses and RAP. The data clearly demonstrate the superior features of CAP with regard to robustness and efficiency, even under conditions of weakly fulfilled adiabaticity. The experimental demonstration of composite sequences to support adiabatic passage is of significant relevance whenever a high efficiency or robustness of coherent excitation processes need to be maintained, e.g., as required in quantum information technology.

  13. Experimental Robust Control of Structural Acoustic Radiation

    NASA Technical Reports Server (NTRS)

    Cox, David E.; Gibbs, Gary P.; Clark, Robert L.; Vipperman, Jeffrey S.

    1998-01-01

    This work addresses the design and application of robust controllers for structural acoustic control. Both simulation and experimental results are presented. H(infinity) and mu-synthesis design methods were used to design feedback controllers which minimize power radiated from a panel while avoiding instability due to unmodeled dynamics. Specifically, high order structural modes which couple strongly to the actuator-sensor path were poorly modeled. This model error was analytically bounded with an uncertainty model, which allowed controllers to be designed without artificial limits on control effort. It is found that robust control methods provide the control designer with physically meaningful parameters with which to tune control designs and can be very useful in determining limits of performance. Experimental results also showed, however, poor robustness properties for control designs with ad-hoc uncertainty models. The importance of quantifying and bounding model errors is discussed.

  14. Helicopter impulsive noise - Theoretical and experimental status

    NASA Technical Reports Server (NTRS)

    Schmitz, F. H.; Yu, Y. H.

    1986-01-01

    The theoretical and experimental status of helicopter impulsive noise is reviewed. The two major source mechanisms of helicopter impulsive noise are addressed: high-speed impulsive noise and blade-vortex interaction impulsive noise. A thorough physical explanation of both generating mechanism is presented together with model and full-scale measurements of the phenomena. Current theoretical prediction methods are compared with experimental findings of isolated rotor tests. The noise generating mechanism of high speed impulsive noise are fairly well understood - theory and experiment compare nicely over Mach number ranges typical of today's helicopters. For the case of blade-vortex interaction noise, understanding of noise generating mechanisms and theoretical comparison with experiment are less satisfactory. Several methods for improving theory-experiment are suggested.

  15. Helicopter impulsive noise: Theoretical and experimental status

    NASA Technical Reports Server (NTRS)

    Schmitz, F. H.; Yu, Y. H.

    1983-01-01

    The theoretical and experimental status of helicopter impulsive noise is reviewed. The two major source mechanisms of helicopter impulsive noise are addressed: high-speed impulsive noise and blade-vortex interaction impulsive noise. A thorough physical explanation of both generating mechanism is presented together with model and full-scale measurements of the phenomena. Current theoretical prediction methods are compared with experimental findings of isolated rotor tests. The noise generating mechanism of high speed impulsive noise are fairly well understood - theory and experiment compare nicely over Mach number ranges typical of today's helicopters. For the case of blade-vortex interaction noise, understanding of noise generating mechanisms and theoretical comparison with experiment are less satisfactory. Several methods for improving theory-experiment are suggested.

  16. Helicopter impulsive noise - Theoretical and experimental status

    NASA Technical Reports Server (NTRS)

    Schmitz, F. H.; Yu, Y. H.

    1986-01-01

    The theoretical and experimental status of helicopter impulsive noise is reviewed. The two major source mechanisms of helicopter impulsive noise are addressed: high-speed impulsive noise and blade-vortex interaction impulsive noise. A thorough physical explanation of both generating mechanisms is presented together with model and full-scale measurements of the phenomena. Current theoretical prediction methods are compared with experimental findings of isolated rotor tests. The noise generating mechanisms of high speed impulsive noise are fairly well understood - theory and experiment compare nicely over Mach number ranges typical of today's helicopters. For the case of blade-vortex interaction noise, understanding of noise generating mechanisms and theoretical comparison with experiment are less satisfactory. Several methods for improving theory/experiment are suggested.

  17. Experimental demonstration of an acoustic magnifying hyperlens.

    PubMed

    Li, Jensen; Fok, Lee; Yin, Xiaobo; Bartal, Guy; Zhang, Xiang

    2009-12-01

    Acoustic metamaterials can manipulate sound waves in surprising ways, which include collimation, focusing, cloaking, sonic screening and extraordinary transmission. Recent theories suggested that imaging below the diffraction limit using passive elements can be realized by acoustic superlenses or magnifying hyperlenses. These could markedly enhance the capabilities in underwater sonar sensing, medical ultrasound imaging and non-destructive materials testing. However, these proposed approaches suffer narrow working frequency bands and significant resonance-induced loss, which hinders them from successful experimental realization. Here, we report the experimental demonstration of an acoustic hyperlens that magnifies subwavelength objects by gradually converting evanescent components into propagating waves. The fabricated acoustic hyperlens relies on straightforward cutoff-free propagation and achieves deep-subwavelength resolution with low loss over a broad frequency bandwidth.

  18. Improving the physiological realism of experimental models.

    PubMed

    Vinnakota, Kalyan C; Cha, Chae Y; Rorsman, Patrik; Balaban, Robert S; La Gerche, Andre; Wade-Martins, Richard; Beard, Daniel A; Jeneson, Jeroen A L

    2016-04-01

    The Virtual Physiological Human (VPH) project aims to develop integrative, explanatory and predictive computational models (C-Models) as numerical investigational tools to study disease, identify and design effective therapies and provide an in silico platform for drug screening. Ultimately, these models rely on the analysis and integration of experimental data. As such, the success of VPH depends on the availability of physiologically realistic experimental models (E-Models) of human organ function that can be parametrized to test the numerical models. Here, the current state of suitable E-models, ranging from in vitro non-human cell organelles to in vivo human organ systems, is discussed. Specifically, challenges and recent progress in improving the physiological realism of E-models that may benefit the VPH project are highlighted and discussed using examples from the field of research on cardiovascular disease, musculoskeletal disorders, diabetes and Parkinson's disease.

  19. Experimental illumination of a fitness landscape

    PubMed Central

    Hietpas, Ryan T.; Jensen, Jeffrey D.; Bolon, Daniel N. A.

    2011-01-01

    The genes of all organisms have been shaped by selective pressures. The relationship between gene sequence and fitness has tremendous implications for understanding both evolutionary processes and functional constraints on the encoded proteins. Here, we have exploited deep sequencing technology to experimentally determine the fitness of all possible individual point mutants under controlled conditions for a nine-amino acid region of Hsp90. Over the past five decades, limited glimpses into the relationship between gene sequence and function have sparked a long debate regarding the distribution, relative proportion, and evolutionary significance of deleterious, neutral, and advantageous mutations. Our systematic experimental measurement of fitness effects of Hsp90 mutants in yeast, evaluated in the light of existing population genetic theory, are remarkably consistent with a nearly neutral model of molecular evolution. PMID:21464309

  20. Experimental generation of amplitude squeezed vector beams.

    PubMed

    Chille, Vanessa; Berg-Johansen, Stefan; Semmler, Marion; Banzer, Peter; Aiello, Andrea; Leuchs, Gerd; Marquardt, Christoph

    2016-05-30

    We present an experimental method for the generation of amplitude squeezed high-order vector beams. The light is modified twice by a spatial light modulator such that the vector beam is created by means of a collinear interferometric technique. A major advantage of this approach is that it avoids systematic losses, which are detrimental as they cause decoherence in continuous-variable quantum systems. The utilisation of a spatial light modulator (SLM) gives the flexibility to switch between arbitrary mode orders. The conversion efficiency with our setup is only limited by the efficiency of the SLM. We show the experimental generation of Laguerre-Gauss (LG) modes with radial indices 0 or 1 and azimuthal indices up to 3 with complex polarization structures and a quantum noise reduction up to -0.9dB±0.1dB. The corresponding polarization structures are studied in detail by measuring the spatial distribution of the Stokes parameters. PMID:27410153

  1. Strategies of cell biology experimentation in space.

    PubMed

    Cogoli, Augusto

    2004-03-01

    The purpose of this article is to inform newcomers on the most important aspects of experimentation with living cells and tissues in space laboratories and platforms. There are strong arguments that justify the efforts and investments in such activity. Experimentation in space is subject to safety and technological constraints that require considerable attention to the development of the flight protocols and of the flight instrumentation. Nevertheless to fly an experiment in space is a unique opportunity to study living systems under conditions not reproducible on Earth and it is also a contribution to human exploration of space. Thereby important progress in basic and applied science can be expected. Parallel investigations on ground with devices averaging the exposure to the gravity vector but not reproducing microgravity shall always be part of a space flight project.

  2. An experimental increase in stuttering frequency.

    PubMed

    Martin, R R; Haroldson, S K

    1988-06-01

    The purpose of the present experiment was to investigate whether stuttering frequency could be increased from baseline by an experimental condition. Initially, 10 adult stutterers spoke spontaneously while alone. Next, they continued speaking, but with an adult, male conversationalist. Finally, the subjects again spoke while alone. Percent stuttering increased in the conversational situation compared with the baseline (alone) situation, and decreased in the final baseline (alone) situation compared with the conversational situation.

  3. Experimental observation of spectral Bloch oscillations.

    PubMed

    Bersch, Christoph; Onishchukov, Georgy; Peschel, Ulf

    2009-08-01

    We report on the first, to our knowledge, experimental observation of spectral Bloch oscillations in an optical fiber employing the interaction between a probe signal and a traveling-wave periodic potential. The spectrum of weak probe pulses is shown to oscillate on account of their group-velocity mismatch to the periodic field. The behavior of a cw probe spectrum reveals the actual discrete nature of the effect. Recurrences of the spectrum after one and two Bloch periods are demonstrated.

  4. Experimenters' reference based upon Skylab experiment management

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The methods and techniques for experiment development and integration that evolved during the Skylab Program are described to facilitate transferring this experience to experimenters in future manned space programs. Management responsibilities and the sequential process of experiment evolution from initial concept through definition, development, integration, operation and postflight analysis are outlined and amplified, as appropriate. Emphasis is placed on specific lessons learned on Skylab that are worthy of consideration by future programs.

  5. Experimental Results for Space-Wire-D

    NASA Astrophysics Data System (ADS)

    Parkes, Steve; Gibson, David; Ferrer, Albert

    2015-09-01

    SpaceWire-D is a deterministic extension to SpaceWire that uses time-division multiplexing to schedule traffic within time-slots. It allows a single SpaceWire network to be used for both time-critical avionics control applications and asynchronous payload data-handling simultaneously using existing SpaceWire technology. In this paper we describe the services of SpaceWire-D and present experimental results for each service.

  6. Experimental observation of a photon bouncing ball.

    PubMed

    Della Valle, G; Savoini, M; Ornigotti, M; Laporta, P; Foglietti, V; Finazzi, M; Duò, L; Longhi, S

    2009-05-01

    An optical analogue of a quantum particle bouncing on a hard surface under the influence of gravity (a quantum bouncer) is experimentally demonstrated using a circularly curved optical waveguide. Spatially resolved tunneling optical microscopy measurements of multiple beam reflections at the waveguide edge clearly show the appearance of wave packet collapses and revivals (either integer and fractional), corresponding to the full quantum regime of the quantum bouncer.

  7. Experimental Observation of a Photon Bouncing Ball

    NASA Astrophysics Data System (ADS)

    Della Valle, G.; Savoini, M.; Ornigotti, M.; Laporta, P.; Foglietti, V.; Finazzi, M.; Duò, L.; Longhi, S.

    2009-05-01

    An optical analogue of a quantum particle bouncing on a hard surface under the influence of gravity (a quantum bouncer) is experimentally demonstrated using a circularly curved optical waveguide. Spatially resolved tunneling optical microscopy measurements of multiple beam reflections at the waveguide edge clearly show the appearance of wave packet collapses and revivals (either integer and fractional), corresponding to the full quantum regime of the quantum bouncer.

  8. Atomic masses from (mainly) experimental data

    SciTech Connect

    Wapstra, A.H.; Audi, G.; Hoekstra, R.

    1988-07-01

    The present list of atomic masses is an update from the 1983 Atomic Mass Table. Two categories of mass values are represented in the tabulation: those derived purely from experimental data, and those calculated with the help of systematic trends also. In order to improve the reliability of the mass values of the latter category, a novel method of extrapolation has been added capitalizing on new formulas for neutron and proton pairing energies. copyright 1988 Academic Press, Inc.

  9. Interactive experimenters' planning procedures and mission control

    NASA Technical Reports Server (NTRS)

    Desjardins, R. L.

    1973-01-01

    The computerized mission control and planning system routinely generates a 24-hour schedule in one hour of operator time by including time dimensions into experimental planning procedures. Planning is validated interactively as it is being generated segment by segment in the frame of specific event times. The planner simply points a light pen at the time mark of interest on the time line for entering specific event times into the schedule.

  10. Experimental network synchronization via plastic optical fiber

    NASA Astrophysics Data System (ADS)

    Arellano-Delgado, A.; López-Gutiérrez, R. M.; Cruz-Hernández, C.; Posadas-Castillo, C.; Cardoza-Avendaño, L.; Serrano-Guerrero, H.

    2013-03-01

    In this paper, network synchronization of coupled Chua's circuits in star configuration is experimentally studied. In particular, plastic optical fiber (POF) is used in the network like communication channels among chaotic nodes to achieve synchronization. The master signal is sent to multiple slaves through a fiber optical coupler with corresponding electrical/optical and optical/electrical stages. An application to encrypted chaotic communication to transmit analogical signal and image messages to multiple receivers is also given.

  11. EXPERIMENTAL BENCHMARKING OF THE MAGNETIZED FRICTION FORCE.

    SciTech Connect

    FEDOTOV, A.V.; GALNANDER, B.; LITVINENKO, V.N.; LOFNES, T.; SIDORIN, A.O.; SMIRNOV, A.V.; ZIEMANN, V.

    2005-09-18

    High-energy electron cooling, presently considered as essential tool for several applications in high-energy and nuclear physics, requires accurate description of the friction force. A series of measurements were performed at CELSIUS with the goal to provide accurate data needed for the benchmarking of theories and simulations. Some results of accurate comparison of experimental data with the friction force formulas are presented.

  12. How Can We Test Seesaw Experimentally?

    SciTech Connect

    Buckley, Matthew R.; Murayama, Hitoshi

    2006-06-07

    The seesaw mechanism for the small neutrino mass has been a popular paradigm, yet it has been believed that there is no way to test it experimentally. We present a conceivable outcome from future experiments that would convince us of the seesaw mechanism. It would involve a variety of data from LHC, ILC, cosmology, underground, and low-energy flavor violation experiments to establish the case.

  13. Experimental system and component performance analysis

    SciTech Connect

    Peterman, K.

    1984-10-01

    A prototype dye laser flow loop was constructed to flow test large power amplifiers in Building 169. The flow loop is designed to operate at supply pressures up to 900 psig and flow rates up to 250 GPM. During the initial startup of the flow loop experimental measurements were made to evaluate component and system performance. Three candidate dye flow loop pumps and three different pulsation dampeners were tested.

  14. A method for experimental modal separation

    NASA Technical Reports Server (NTRS)

    Hallauer, W. L., Jr.

    1977-01-01

    A method is described for the numerical simulation of multiple-shaker modal survey testing using simulated experimental data to optimize the shaker force-amplitude distribution for the purpose of isolating individual modes of vibration. Inertia, damping, stiffness, and model data are stored on magnetic disks, available by direct access to the interactive FORTRAN programs which perform all computations required by this relative force amplitude distribution method.

  15. Experimental Observation of a Photon Bouncing Ball

    SciTech Connect

    Della Valle, G.; Ornigotti, M.; Laporta, P.; Longhi, S.; Savoini, M.; Finazzi, M.; Duo, L.; Foglietti, V.

    2009-05-08

    An optical analogue of a quantum particle bouncing on a hard surface under the influence of gravity (a quantum bouncer) is experimentally demonstrated using a circularly curved optical waveguide. Spatially resolved tunneling optical microscopy measurements of multiple beam reflections at the waveguide edge clearly show the appearance of wave packet collapses and revivals (either integer and fractional), corresponding to the full quantum regime of the quantum bouncer.

  16. Experimental treatment of recurrent otitis externa.

    PubMed

    Mileva, M H; Pencheva, D V; Bryaskova, R G; Genova-Kalou, P D; Kantardjiev, T V

    2015-01-01

    The aim of this research is to determine the effect of the hybrid material based on polyvinyl alcohol and silver nanoparticles (PVA/AgNps) in the treatment of the otitis externa as an additional component in the commercial product "Betazon Trio". It was established that the experimental creamy formula with silver concentration 600 mg/L is suitable for recovery of the microbial homeostasis when it is administrated once daily in dose 1 ml over a period of 14 days.

  17. Dr. von Braun With German Rocket Experimenters

    NASA Technical Reports Server (NTRS)

    1930-01-01

    Dr. von Braun was among a famous group of rocket experimenters in Germany in the 1930s. This photograph is believed to be made on the occasion of Herman Oberth's Kegelduese liquid rocket engine being certified as to performance during firing. From left to right are R. Nebel, Dr. Ritter, Mr. Baermueller, Kurt Heinish, Herman Oberth, Klaus Riedel, Wernher von Braun, and an unidentified person.

  18. Experimental history: swinging pendulums and melting shellac.

    PubMed

    Palmieri, Paolo

    2009-09-01

    Four hundred years ago Galileo Galilei aimed a telescope at the sky. He revolutionized astronomy. Equally revolutionary were his experiments in physics. Unlike his astronomical observations the experiments remain difficult to understand and replicate even today. Two centuries after Galileo, Augustin Coulomb demonstrated experimentally the law of electrostatic force. It has never been successfully replicated. Yet both Galileo and Coulomb were exquisite experimentalists. The fact is that revolutionary experiments in physics are never finished. They are open for investigation for generations to come.

  19. Transonic rotor noise: Theoretical and experimental comparisons

    NASA Technical Reports Server (NTRS)

    Schmitz, F. H.; Yu, Y. H.

    1980-01-01

    Two complementary methods of describing the high speed rotor noise problem are discussed. The first method uses the second order transonic potential equation to define and characterize the nature of the aerodynamic and acoustic fields and to explain the appearance of radiating shock waves. The second employs the Ffowcs Williams and Hawkings equation to successfully calculate the acoustic far field. Good agreement between theoretical and experimental waveforms is shown for transonic hover tip Mach numbers from 0.8 to 0.9.

  20. Experimental generation of optical coherence lattices

    NASA Astrophysics Data System (ADS)

    Chen, Yahong; Ponomarenko, Sergey A.; Cai, Yangjian

    2016-08-01

    We report experimental generation and measurement of recently introduced optical coherence lattices. The presented optical coherence lattice realization technique hinges on a superposition of mutually uncorrelated partially coherent Schell-model beams with tailored coherence properties. We show theoretically that information can be encoded into and, in principle, recovered from the lattice degree of coherence. Our results can find applications to image transmission and optical encryption.