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Sample records for partial ornithine transcarbamylase

  1. Antepartum Ornithine Transcarbamylase Deficiency

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    Hitoshi Nakajima

    2014-11-01

    Full Text Available Ornithine transcarbamylase deficiency (OTCD is the most common type urea cycle enzyme deficiencies. This syndrome results from a deficiency of the mitochondrial enzyme ornithine transcarbamylase, which catalyzes the conversion of ornithine and carbamoyl phosphate to citrullin. Our case was a 28-year-old female diagnosed with OTCD following neurocognitive deficit during her first pregnancy. Although hyperammonemia was suspected as the cause of the patient's mental changes, there was no evidence of chronic liver disease. Plasma amino acid and urine organic acid analysis revealed OTCD. After combined modality treatment with arginine, sodium benzoate and hemodialysis, the patient's plasma ammonia level stabilized and her mental status returned to normal. At last she recovered without any damage left.

  2. Genetics Home Reference: ornithine transcarbamylase deficiency

    Science.gov (United States)

    ... belongs to a class of genetic diseases called urea cycle disorders. The urea cycle is a sequence of reactions ... Baby's First Test GeneReview: Ornithine Transcarbamylase Deficiency GeneReview: Urea Cycle Disorders Overview MedlinePlus Encyclopedia: Hereditary urea cycle abnormality National ...

  3. Late-onset ornithine transcarbamylase deficiency: An under recognized cause of metabolic encephalopathy

    OpenAIRE

    Rush, Eric T; Hartmann, Julianne E; Skrabal, Jill C; Rizzo, William B

    2014-01-01

    Introduction: Ornithine transcarbamylase deficiency is the most common inherited disorder of the urea cycle, has a variable phenotype, and is caused by mutations in the OTC gene. We report three cases of ornithine transcarbamylase deficiency to illustrate the late-onset presentation of this disorder and provide strategies for diagnosis and treatment. The patients were maternal first cousins, presenting with hyperammonemia and obtundation. Urea cycle disorder was not initially suspected in the...

  4. At the intersection of toxicology, psychiatry, and genetics: a diagnosis of ornithine transcarbamylase deficiency.

    Science.gov (United States)

    Sloas, Harold Andrew; Ence, Thomas C; Mendez, Donna R; Cruz, Andrea T

    2013-09-01

    Ornithine transcarbamylase (OTC) deficiency is a genetic disorder involving a mutation of the ornithine transcarbamylase gene, located on the short arm of the X chromosome (Xp21.1). This makes the expression of the gene most common in homozygous males, but heterozygous females can also be affected and may be more likely to suffer from serious morbidity. Most males present early in the neonatal period with more devastating outcomes than their female counterparts. Up to 34% will present in the first 30 days of life (J Pediatr 2001;138:S30). Females often have partially functioning mitochondria due to uneven distribution of the mutant gene secondary to lyonization (“X-chromosome Inactivation”. Genetics Home Reference, 2012). Occasionally, symptomatic females may not even present until they are placed under metabolic stress such as a severe illness, fasting, pregnancy, or new medication (Roth KS, Steiner RD. “Ornithine Transcarbamylase Deficiency”. EMedicine, 2012). The urea cycle is the body's primary tool for the disposal of excess nitrogen, which is generated by the routine metabolism of proteins and amino acids. Mitochondrial dysfunction impairs urea production and result in hyperammonemia (Semin Neonatol 2002;7:27). The sine qua non among all degrees of OTC deficiency at presentation is hyperammonemia. As in adults, children will have similar symptoms of encephalopathy, but this may be expressed differently depending on the child's developmental level. We present an unusual case of OTC deficiency in an older child with undifferentiated symptoms of an anticholinergic toxidrome, liver failure, iron overdose, and mushroom poisoning.

  5. Posterior fossa syndrome in a patient with an ornithine transcarbamylase deficiency

    NARCIS (Netherlands)

    Nedermeijer, S. C M; Van Den Hout, J.; Geleijns, C.; De Klerk, H.; Catsman-Berrevoets, C. E.

    2015-01-01

    The posterior fossa syndrome (PFS) is a well-known clinical entity and mainly occurs in children. Ornithine transcarbamylase deficiency (OTC) is the most common urea cycle disorder, which occurs in an estimated 1 per 50.000 live births in Japan. Symptoms are mostly due to hyperammonemia and include

  6. ORNITHINE TRANSCARBAMYLASE DEFICIENCY – THE REAL CAUSE OF “FAMILY CURSE”. A CASE REPORT

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    Zh. Sh. Bagomedova

    2016-01-01

    Full Text Available Ornithine transcarbamylase deficiency (type II hyperammonemia – X-linked metabolic disorder of the urea cycle, caused by mutations of the gene encoding ornithine transcarbamylase (OTC. Changes to the nervous system caused by degenerative processes in the gray and white matter of the cerebral hemispheres. The authors describe 1-year-old boy with ornithine transcarbamylase deficiency as a clinical example, with the onset of the disease in the first year of life, with refusal of food, vomiting, weakness and tiredness progressing to lethargy and unconsciousness, convulsive seizures, refusal from meat in the interictal period, delayed of psychomotor development. The child was admitted to the children’s intensive care unit in serious condition, unconscious with severe neurological symptoms. The clinical picture, the results of instrumental and laboratory examination and the presence of family history were the basis for the assumption of the hereditary origin of the disease. Genetic further examination was planned. In the context of children’s intensive care unit, the patient was undergoing of intensive therapy, which had no effect. Death occurred on the 5th day of hospitalization. To verify the diagnosis post-mortem autopsy was conducted, based on which was installed the immediate cause of death. In confirming the diagnosis is considered as tandem mass spectrometry, and DNA diagnostics.

  7. Overexpression, purification, crystallization and preliminary structural studies of catabolic ornithine transcarbamylase from Lactobacillus hilgardii

    International Nuclear Information System (INIS)

    Rivas, Blanca de las; Rodríguez, Héctor; Angulo, Iván; Muñoz, Rosario; Mancheño, José M.

    2007-01-01

    The catabolic ornithine transcarbamylase (cOTC) from L. hilgardii has been overexpressed in E. coli, purified and crystallized under two different experimental conditions. The structure has been solved by the molecular-replacement method using the atomic coordinates of catabolic ornithine transcarbamylase from P. aeruginosa as the search model. The catabolic ornithine transcarbamylase (cOTC; EC 2.1.3.3) from the lactic acid bacteria Lactobacillus hilgardii is a key protein involved in the degradation of arginine during malolactic fermentation. cOTC containing an N-terminal His 6 tag has been overexpressed in Escherichia coli, purified and crystallized under two different experimental conditions using the hanging-drop vapour-diffusion method. Crystals obtained from a solution containing 8%(w/v) PEG 4000, 75 mM sodium acetate pH 4.6 belong to the trigonal space group P321 and have unit-cell parameters a = b = 157.04, c = 79.28 Å. Conversely, crystals grown in 20%(v/v) 2-methyl-2,4-pentanediol, 7.5%(w/v) PEG 4000, 100 mM HEPES pH 7.8 belong to the monoclinic space group C2 and have unit-cell parameters a = 80.06, b = 148.90, c = 91.67 Å, β = 100.25°. Diffraction data were collected in-house to 3.00 and 2.91 Å resolution for trigonal and monoclinic crystals, respectively. The estimated Matthews coefficient for the crystal forms were 2.36 and 2.24 Å 3 Da −1 , respectively, corresponding to 48% and 45% solvent content. In both cases, the results are consistent with the presence of three protein subunits in the asymmetric unit. The structure of cOTC has been determined by the molecular-replacement method using the atomic coordinates of cOTC from Pseudomonas aeruginosa (PDB code) as the search model

  8. Reduced Functional Connectivity of Default Mode and Set-Maintenance Networks in Ornithine Transcarbamylase Deficiency.

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    Ileana Pacheco-Colón

    Full Text Available Ornithine transcarbamylase deficiency (OTCD is an X-chromosome linked urea cycle disorder (UCD that causes hyperammonemic episodes leading to white matter injury and impairments in executive functioning, working memory, and motor planning. This study aims to investigate differences in functional connectivity of two resting-state networks--default mode and set-maintenance--between OTCD patients and healthy controls.Sixteen patients with partial OTCD and twenty-two control participants underwent a resting-state scan using 3T fMRI. Combining independent component analysis (ICA and region-of-interest (ROI analyses, we identified the nodes that comprised each network in each group, and assessed internodal connectivity.Group comparisons revealed reduced functional connectivity in the default mode network (DMN of OTCD patients, particularly between the anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC node and bilateral inferior parietal lobule (IPL, as well as between the ACC/mPFC node and the posterior cingulate cortex (PCC node. Patients also showed reduced connectivity in the set-maintenance network, especially between right anterior insula/frontal operculum (aI/fO node and bilateral superior frontal gyrus (SFG, as well as between the right aI/fO and ACC and between the ACC and right SFG.Internodal functional connectivity in the DMN and set-maintenance network is reduced in patients with partial OTCD compared to controls, most likely due to hyperammonemia-related white matter damage. Because several of the affected areas are involved in executive functioning, it is postulated that this reduced connectivity is an underlying cause of the deficits OTCD patients display in this cognitive domain.

  9. Late-onset ornithine transcarbamylase deficiency: An under recognized cause of metabolic encephalopathy

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    Eric T Rush

    2014-07-01

    Full Text Available Introduction: Ornithine transcarbamylase deficiency is the most common inherited disorder of the urea cycle, has a variable phenotype, and is caused by mutations in the OTC gene. We report three cases of ornithine transcarbamylase deficiency to illustrate the late-onset presentation of this disorder and provide strategies for diagnosis and treatment. The patients were maternal first cousins, presenting with hyperammonemia and obtundation. Urea cycle disorder was not initially suspected in the first patient, delaying diagnosis. Results: Sequencing of the OTC gene showed a novel missense mutation, c.563G > C (p.G188A. Numerous family members were found to carry this mutation, which shows a trend toward later onset. Each urea cycle disorder has its own unique pattern of biochemical abnormalities, which differ from non-metabolic causes of critical illness. Conclusion: Regardless of age, clinical suspicion of a urea cycle disorder is important in encephalopathic patients to ensure quick diagnosis and definitive treatment of the underlying inborn error of metabolism.

  10. Overexpression, purification, crystallization and preliminary structural studies of catabolic ornithine transcarbamylase from Lactobacillus hilgardii

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    Rivas, Blanca de las; Rodríguez, Héctor [Instituto de Fermentaciones Industriales, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Angulo, Iván [Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain); Muñoz, Rosario [Instituto de Fermentaciones Industriales, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Mancheño, José M., E-mail: xjosemi@iqfr.csic.es [Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain); Instituto de Fermentaciones Industriales, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain)

    2007-07-01

    The catabolic ornithine transcarbamylase (cOTC) from L. hilgardii has been overexpressed in E. coli, purified and crystallized under two different experimental conditions. The structure has been solved by the molecular-replacement method using the atomic coordinates of catabolic ornithine transcarbamylase from P. aeruginosa as the search model. The catabolic ornithine transcarbamylase (cOTC; EC 2.1.3.3) from the lactic acid bacteria Lactobacillus hilgardii is a key protein involved in the degradation of arginine during malolactic fermentation. cOTC containing an N-terminal His{sub 6} tag has been overexpressed in Escherichia coli, purified and crystallized under two different experimental conditions using the hanging-drop vapour-diffusion method. Crystals obtained from a solution containing 8%(w/v) PEG 4000, 75 mM sodium acetate pH 4.6 belong to the trigonal space group P321 and have unit-cell parameters a = b = 157.04, c = 79.28 Å. Conversely, crystals grown in 20%(v/v) 2-methyl-2,4-pentanediol, 7.5%(w/v) PEG 4000, 100 mM HEPES pH 7.8 belong to the monoclinic space group C2 and have unit-cell parameters a = 80.06, b = 148.90, c = 91.67 Å, β = 100.25°. Diffraction data were collected in-house to 3.00 and 2.91 Å resolution for trigonal and monoclinic crystals, respectively. The estimated Matthews coefficient for the crystal forms were 2.36 and 2.24 Å{sup 3} Da{sup −1}, respectively, corresponding to 48% and 45% solvent content. In both cases, the results are consistent with the presence of three protein subunits in the asymmetric unit. The structure of cOTC has been determined by the molecular-replacement method using the atomic coordinates of cOTC from Pseudomonas aeruginosa (PDB code) as the search model.

  11. Correction of mouse ornithine transcarbamylase deficiency by gene transfer into the germ line

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    Cavard, C; Grimber, G; Dubois, N; Chasse, J F; Bennoun, M; Minet-Thuriaux, M; Kamoun, P; Briand, P

    1988-03-25

    The sparse fur with abnormal skin and hair (Spf-ash) mouse is a model for the human x-linked hereditary disorder, ornithine transcarbamylase (OTC) deficiency. In Spf-ash mice, both OTC mRNA and enzyme activity are 5% of control values resulting in hyperammonemia, pronounced orotic aciduria and an abnormal phenotype characterized by growth retardation and sparse fur. Using microinjection, the authors introduced a construction containing rat OTC cDNA linked to the SV40 early promoter into fertilized eggs of Spf-ash mice. The expression of the transgene resulted in the development of a transgenic mouse whose phenotype and orotic acid excretion are fully normalized. Thus, the possibility of correcting hereditary enzymatic defect by gene transfer of heterologous cDNA coding for the normal enzyme has been demonstrated.

  12. Purification and characterization of ornithine transcarbamylase from pea (Pisum sativum L.)

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    Slocum, R. D.; Richardson, D. P.

    1991-01-01

    Pea (Pisum sativum) ornithine transcarbamylase (OTC) was purified to homogeneity from leaf homogenates in a single-step procedure, using delta-N-(phosphonacetyl)-L-ornithine-Sepharose 6B affinity chromatography. The 1581-fold purified OTC enzyme exhibited a specific activity of 139 micromoles citrulline per minute per milligram of protein at 37 degrees C, pH 8.5. Pea OTC represents approximately 0.05% of the total soluble protein in the leaf. The molecular weight of the native enzyme was approximately 108,200, as estimated by Sephacryl S-200 gel filtration chromatography. The purified protein ran as a single molecular weight band of 36,500 in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These results suggest that the pea OTC is a trimer of identical subunits. The overall amino acid composition of pea OTC is similar to that found in other eukaryotic and prokaryotic OTCs, but the number of arginine residues is approximately twofold higher. The increased number of arginine residues probably accounts for the observed isoelectric point of 7.6 for the pea enzyme, which is considerably more basic than isoelectric point values that have been reported for other OTCs.

  13. Switch from Sodium Phenylbutyrate to Glycerol Phenylbutyrate Improved Metabolic Stability in an Adolescent with Ornithine Transcarbamylase Deficiency.

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    Laemmle Alexander; Stricker Tamar; Häberle Johannes

    2016-01-01

    A male patient, born in 1999, was diagnosed with ornithine transcarbamylase deficiency as neonate and was managed with a strict low-protein diet supplemented with essential amino acids, l-citrulline, and l-arginine as well as sodium benzoate. He had an extensive history of hospitalizations for hyperammonemic crises throughout childhood and early adolescence, which continued after the addition of sodium phenylbutyrate in 2009. In December 2013 he was switched to glycerol phenylbutyrate, and hi...

  14. Acute metabolic decompensation due to influenza in a mouse model of ornithine transcarbamylase deficiency

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    Peter J. McGuire

    2014-02-01

    Full Text Available The urea cycle functions to incorporate ammonia, generated by normal metabolism, into urea. Urea cycle disorders (UCDs are caused by loss of function in any of the enzymes responsible for ureagenesis, and are characterized by life-threatening episodes of acute metabolic decompensation with hyperammonemia (HA. A prospective analysis of interim HA events in a cohort of individuals with ornithine transcarbamylase (OTC deficiency, the most common UCD, revealed that intercurrent infection was the most common precipitant of acute HA and was associated with markers of increased morbidity when compared with other precipitants. To further understand these clinical observations, we developed a model system of metabolic decompensation with HA triggered by viral infection (PR8 influenza using spf-ash mice, a model of OTC deficiency. Both wild-type (WT and spf-ash mice displayed similar cytokine profiles and lung viral titers in response to PR8 influenza infection. During infection, spf-ash mice displayed an increase in liver transaminases, suggesting a hepatic sensitivity to the inflammatory response and an altered hepatic immune response. Despite having no visible pathological changes by histology, WT and spf-ash mice had reduced CPS1 and OTC enzyme activities, and, unlike WT, spf-ash mice failed to increase ureagenesis. Depression of urea cycle function was seen in liver amino acid analysis, with reductions seen in aspartate, ornithine and arginine during infection. In conclusion, we developed a model system of acute metabolic decompensation due to infection in a mouse model of a UCD. In addition, we have identified metabolic perturbations during infection in the spf-ash mice, including a reduction of urea cycle intermediates. This model of acute metabolic decompensation with HA due to infection in UCD serves as a platform for exploring biochemical perturbations and the efficacy of treatments, and could be adapted to explore acute decompensation in other

  15. Ornithine Transcarbamylase Deficiency: If at First You Do Not Diagnose, Try and Try Again

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    Christan D. Santos

    2017-01-01

    Full Text Available Ornithine transcarbamylase (OTC deficiency is well known for its diagnosis in the neonatal period. Presentation often occurs after protein feeding and manifests as poor oral intake, vomiting, lethargy progressing to seizure, respiratory difficulty, and eventually coma. Presentation at adulthood is rare (and likely underdiagnosed; however, OTC deficiency can be life-threatening and requires prompt investigation and treatment. Reports and guidelines are scarce due to its rarity. Here, we present a 59-year-old woman with a past history of irritable bowel syndrome who underwent a reparative operation for rectal prolapse and enterocele. Her postoperative course was complicated by a bowel perforation (which was repaired, prolonged mechanical ventilation, tracheostomy, critical illness myopathy, protein-caloric malnutrition, and altered mental status. After standard therapy for delirium failed, further investigation showed hyperammonemia and increased urine orotic acid, ultimately leading to the diagnosis of OTC deficiency. This case highlights the importance of considering OTC deficiency in hospitalized adults, especially during the diagnostic evaluation for altered mental status.

  16. Multidisciplinary management of ornithine transcarbamylase (OTC) deficiency in pregnancy: essential to prevent hyperammonemic complications

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    Lamb, Stephanie; Aye, Christina Yi Ling; Murphy, Elaine; Mackillop, Lucy

    2013-01-01

    Ornithine transcarbamylase (OTC) deficiency is the most common inborn error in the metabolism of the urea cycle with an incidence of 1 in 14 000 live births. Pregnancy can trigger potentially fatal hyperammonemic crises. We report a successful pregnancy in a 29-year-old primiparous patient with a known diagnosis of OTC deficiency since infancy. Hyperammonemic complications were avoided due to careful multidisciplinary management which included a detailed antenatal, intrapartum and postnatal plan. Management principles include avoidance of triggers, a low-protein diet and medications which promote the removal of nitrogen by alternative pathways. Triggers include metabolic stress such as febrile illness, particularly gastroenteritis, fasting and any protein loading. In our case the patient, in addition to a restricted protein intake, was prescribed sodium benzoate 4 g four times a day, sodium phenylbutyrate 2 g four times a day and arginine 500 mg four times a day to aid excretion of ammonia and reduce flux through the urea cycle. PMID:23283608

  17. Switch from Sodium Phenylbutyrate to Glycerol Phenylbutyrate Improved Metabolic Stability in an Adolescent with Ornithine Transcarbamylase Deficiency.

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    Laemmle, Alexander; Stricker, Tamar; Häberle, Johannes

    2017-01-01

    A male patient, born in 1999, was diagnosed with ornithine transcarbamylase deficiency as neonate and was managed with a strict low-protein diet supplemented with essential amino acids, L-citrulline, and L-arginine as well as sodium benzoate. He had an extensive history of hospitalizations for hyperammonemic crises throughout childhood and early adolescence, which continued after the addition of sodium phenylbutyrate in 2009. In December 2013 he was switched to glycerol phenylbutyrate, and his metabolic stability was greatly improved over the following 7 months prior to liver transplant.

  18. Acute treatment of hyperammonemia by continuous renal replacement therapy in a newborn patient with ornithine transcarbamylase deficiency

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    Hyo Jeong Kim

    2011-10-01

    Full Text Available Ornithine transcarbamylase (OTC deficiency is well known as the most common inherited disorder of the urea cycle, and 1 of the most common causes of hyperammonemia in newborns. We experienced a case of a 3-day-old boy with OTC deficiency who appeared healthy in the first 2 days of life but developed lethargy and seizure soon afterwards. His serum ammonia level was measured as >1700 μg/dL (range, 0 to 45 μg/dL. Continuous renal replacement therapy (CRRT in the mode of continuous venovenous hemodiafiltration was immediately applied to correct the raised ammonia level. No seizure occurred after the elevated ammonia level was reduced. Therefore, CRRT should be included as 1 of the treatment modalities for newborns with inborn errors of metabolism, especially hyperammonemia. Here, we report 1 case of successful treatment of hyperammonemia by CRRT in a neonate with OTC deficiency.

  19. Fatal ammonia toxicity in an adult due to an undiagnosed urea cycle defect: under-recognition of ornithine transcarbamylase deficiency.

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    Thurlow, Vanessa R; Asafu-Adjaye, Michelle; Agalou, Stamatina; Rahman, Yusof

    2010-05-01

    There is a lack of awareness of acutely presenting inborn errors of metabolism in adults, of which the X-linked urea cycle defect ornithine transcarbamylase (OTC) deficiency is an example, many comparatively mild mutations having been identified. In male hemizygotes clinical manifestations and age at presentation vary and depend on the mutation. In female heterozygotes the clinical spectrum depends on the extent to which the abnormal gene is expressed. Milder versions of the defect may not cause clear clinical symptoms and may remain unrecognized until the person is subjected to an unusually high nitrogen load when they develop severe hyperammonaemia. During acute episodes liver enzymes may be normal or only slightly elevated and occasionally accompanied by coagulopathy, but the key finding is hyperammonaemia. Boys with these milder forms may exhibit abnormal behaviour and be diagnosed with attention deficit hyperactivity disorder. This case illustrates how late presentation of OTC deficiency in a non-specialist centre can be difficult to differentiate from drug abuse, psychiatric illness or encephalopathy. Failure to measure blood ammonia in adults with unexplained key symptoms - particularly prolonged vomiting without diarrhoea and altered mental state/hallucinations, or to recognize the significance of elevated blood ammonia without evidence of liver decompensation can lead to delayed or missed diagnosis.

  20. A new mouse model of mild ornithine transcarbamylase deficiency (spf-j displays cerebral amino acid perturbations at baseline and upon systemic immune activation.

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    Tatyana N Tarasenko

    Full Text Available Ornithine transcarbamylase deficiency (OTCD, OMIM# 311250 is an inherited X-linked urea cycle disorder that is characterized by hyperammonemia and orotic aciduria. In this report, we describe a new animal model of OTCD caused by a spontaneous mutation in the mouse Otc gene (c.240T>A, p.K80N. This transversion in exon 3 of ornithine transcarbamylase leads to normal levels of mRNA with low levels of mature protein and is homologous to a mutation that has also been described in a single patient affected with late-onset OTCD. With higher residual enzyme activity, spf-J were found to have normal plasma ammonia and orotate. Baseline plasma amino acid profiles were consistent with mild OTCD: elevated glutamine, and lower citrulline and arginine. In contrast to WT, spf-J displayed baseline elevations in cerebral amino acids with depletion following immune challenge with polyinosinic:polycytidylic acid. Our results indicate that the mild spf-J mutation constitutes a new mouse model that is suitable for mechanistic studies of mild OTCD and the exploration of cerebral pathophysiology during acute decompensation that characterizes proximal urea cycle dysfunction in humans.

  1. Liver failure with coagulopathy, hyperammonemia and cyclic vomiting in a toddler revealed to have combined heterozygosity for genes involved with ornithine transcarbamylase deficiency and Wilson disease.

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    Mira, Valerie; Boles, Richard G

    2012-01-01

    A girl with a 2 month history of cyclic episodes of vomiting, diarrhea, and lethargy lasting 2-3 days each presented with acute hepatopathy (ALT 3,500 IU/L) with coagulopathy (PT 55 s) and hyperammonemia (207 μmol/L) at age 1½ years. Biochemical and molecular analyzes revealed ornithine transcarbamylase (OTC) deficiency. While laboratory signs of mild hepatocellular dysfunction are common in OTC deficiency, substantial liver failure with coagulopathy is generally not seen, although four others cases have been reported, three of which presented with cyclic vomiting. Further evaluation in our case revealed elevated urine (198.8 μg/g creatinine) and liver (103 μg/g dry weight) copper content, and a heterozygous mutation in the Wilson disease gene, ATP7B. Our patient, now aged 5 years, has remained in excellent health with normal growth and development on fasting avoidance, a modified vegan diet, and sodium phenylbutyrate.These five cases demonstrate that generalized liver dysfunction/failure is a potential serious complication of OTC deficiency, although not a common one, and suggests that an ALT and PT should be obtained in OTC patients during episodes of hyperammonemia. Cyclic vomiting is a known presentation of OTC deficiency; it is not known if comorbid liver failure predisposes toward this phenotype. We propose that the heterozygote state in ATP7B increases the liver copper content, thus predisposing our patient with OTC deficiency to develop liver failure during a hyperammonemic episode. Our present case is an example of the opportunity of molecular diagnostics to identify putative modifier genes in patients with atypical presentations of genetic disorders.

  2. From Genome to Structure and Back Again: A Family Portrait of the Transcarbamylases

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    Dashuang Shi

    2015-08-01

    Full Text Available Enzymes in the transcarbamylase family catalyze the transfer of a carbamyl group from carbamyl phosphate (CP to an amino group of a second substrate. The two best-characterized members, aspartate transcarbamylase (ATCase and ornithine transcarbamylase (OTCase, are present in most organisms from bacteria to humans. Recently, structures of four new transcarbamylase members, N-acetyl-l-ornithine transcarbamylase (AOTCase, N-succinyl-l-ornithine transcarbamylase (SOTCase, ygeW encoded transcarbamylase (YTCase and putrescine transcarbamylase (PTCase have also been determined. Crystal structures of these enzymes have shown that they have a common overall fold with a trimer as their basic biological unit. The monomer structures share a common CP binding site in their N-terminal domain, but have different second substrate binding sites in their C-terminal domain. The discovery of three new transcarbamylases, l-2,3-diaminopropionate transcarbamylase (DPTCase, l-2,4-diaminobutyrate transcarbamylase (DBTCase and ureidoglycine transcarbamylase (UGTCase, demonstrates that our knowledge and understanding of the spectrum of the transcarbamylase family is still incomplete. In this review, we summarize studies on the structures and function of transcarbamylases demonstrating how structural information helps to define biological function and how small structural differences govern enzyme specificity. Such information is important for correctly annotating transcarbamylase sequences in the genome databases and for identifying new members of the transcarbamylase family.

  3. New insight into the transcarbamylase family: the structure of putrescine transcarbamylase, a key catalyst for fermentative utilization of agmatine.

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    Luis Mariano Polo

    Full Text Available Transcarbamylases reversibly transfer a carbamyl group from carbamylphosphate (CP to an amine. Although aspartate transcarbamylase and ornithine transcarbamylase (OTC are well characterized, little was known about putrescine transcarbamylase (PTC, the enzyme that generates CP for ATP production in the fermentative catabolism of agmatine. We demonstrate that PTC (from Enterococcus faecalis, in addition to using putrescine, can utilize L-ornithine as a poor substrate. Crystal structures at 2.5 Å and 2.0 Å resolutions of PTC bound to its respective bisubstrate analog inhibitors for putrescine and ornithine use, N-(phosphonoacetyl-putrescine and δ-N-(phosphonoacetyl-L-ornithine, shed light on PTC preference for putrescine. Except for a highly prominent C-terminal helix that projects away and embraces an adjacent subunit, PTC closely resembles OTCs, suggesting recent divergence of the two enzymes. Since differences between the respective 230 and SMG loops of PTC and OTC appeared to account for the differential preference of these enzymes for putrescine and ornithine, we engineered the 230-loop of PTC to make it to resemble the SMG loop of OTCs, increasing the activity with ornithine and greatly decreasing the activity with putrescine. We also examined the role of the C-terminal helix that appears a constant and exclusive PTC trait. The enzyme lacking this helix remained active but the PTC trimer stability appeared decreased, since some of the enzyme eluted as monomers from a gel filtration column. In addition, truncated PTC tended to aggregate to hexamers, as shown both chromatographically and by X-ray crystallography. Therefore, the extra C-terminal helix plays a dual role: it stabilizes the PTC trimer and, by shielding helix 1 of an adjacent subunit, it prevents the supratrimeric oligomerizations of obscure significance observed with some OTCs. Guided by the structural data we identify signature traits that permit easy and unambiguous annotation

  4. Case 252: Acute Hyperammonemic Encephalopathy Resulting from Late-Onset Ornithine Transcarbamylase Deficiency.

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    Hershman, Michelle; Carmody, Raymond; Udayasankar, Unni K

    2018-04-01

    History A 19-year-old woman with no pertinent medical history was brought to the emergency department after being found unconscious on her bathroom floor by her roommate. In the preceding weeks, she had reported intractable nausea and vomiting, for which she had been taking ondansetron. No other medications had been prescribed. The day prior to presentation, she had contacted her mother and described increasing confusion. Glasgow coma scale score on arrival in the emergency department was 4. Intravenous naloxone was administered, without immediate response. Initial blood glucose level was 232 mg/dL (12.8 mmol/L) (normal range, 79-140 mg/dL [4.4- 7.7 mmol/L]), and other routine laboratory test results were normal. Urine toxicology results were negative. Cerebrospinal fluid evaluation revealed levels were within normal limits. Neurologic examination revealed dilated pupils, which showed a sluggish response to light, and left lower extremity rigidity with intermittent tremors. Initial unenhanced cranial computed tomographic (CT) findings were negative. Magnetic resonance (MR) imaging of the brain was performed. The patient's condition deteriorated, with increasing cerebral edema over the next week, and she was declared brain dead. Her liver was transplanted into an adult recipient, who subsequently developed cerebral edema and elevated plasma ammonia levels, resulting in death in the immediate postoperative period.

  5. Radiometric microassay for ornithine decarboxylase

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    Maderdrut, J L; Oppenheim, R W [North Carolina Univ., Chapel Hill (USA). School of Medicine

    1978-01-01

    A simple method for purifying (/sup 3/H)L-ornithine and incubation conditions suitable for estimating L-ornithine decarboxylase activity are described. Routine and recycle cation exchange procedures for separating putrescine from ornithine are outlined. Blanks using the routine cation exchange method average approx. 0.04% of the radioactivity contained in the substrate; product recovery is approx. 94%. The L-ornithine decarboxylase assay is proportional to time for at least 8 h. The relationship between substrate purity and the sensitivity of the cation exchange procedures is assessed. Radiochemical purity is the critical determinant of sensitivity for recycled assays. The cation exchange method is compared with the commonly used CO/sub 2/-trapping method. The cation exchange method is more specific and approximately three orders of magnitude more sensitive than the CO/sub 2/-trapping method. L-ornithine decarboxylase activity can be measured reliably in samples of embryonic neural tissues having wet-weights of approx. 1 ..mu..g. L-ornithine decarboxylase activity in the lumbar spinal cord of the chick embryo decreases 25-30 fold from day 5 to day 18 of embryonic development. A cation exchange procedure for estimating L-lysine decarboxylase activity is also described. Failure to detect L-lysine decarboxylase activity in the chick embryo lumbar spinal cord is contrasted with the previous report of high cadaverine levels in chick embryos.

  6. Ornithine transport and exchange in Streptococcus lactis

    International Nuclear Information System (INIS)

    Thompson, J.

    1987-01-01

    Resting cells of Streptococcus lactis 133 appeared to accumulate [ 14 C]ornithine to a high concentration in the absence of an exogenous energy source. However, analysis of intracellular amino acid pool constituents and results of transport experiments revealed that the accumulation of ornithine represented a homoexchange between extracellular [ 14 C]ornithine and unlabeled ornithine in the cell. The energy-independent exchange of ornithine was not inhibited by proton-conducting uncouplers or by metabolic inhibitors. Intracellular [ 14 C]ornithine was retained by resting cells after suspension in a buffered medium. However, addition of unlabeled ornithine to the suspension elicited rapid exit of labeled amino acid. The initial rate of exist of [ 14 C]ornithine was dependent on the concentration of unlabeled ornithine in the medium, but this accelerative exchange diffusion process caused no net loss of amino acid. By contrast, the presence of a fermentable energy source caused a rapid expulsion of and new decrease in the concentration of intracellular ornithine. Kinetic analyses of amino acid transport demonstrated competitive inhibition between lysine and ornithine, and data obtained by two-dimensional thin-layer chromatography established the heteroexchange of these basic amino acids. The effects of amino acids and of ornithine analogs on both entry and exit of [ 14 C]ornithine have been examined. The data suggest that common carrier mediates the entry and exchange of lysine, arginine, and ornithine in cells of S. lactis

  7. Ornithine: the overlooked molecule in the regulation of polyamine metabolism

    Science.gov (United States)

    Rajtilak Majumdar; Lin Shao; Rakesh Minocha; Stephanie Long; Subhash C. Minocha

    2013-01-01

    We overexpressed a mouse ornithine decarboxylase gene under the control of a constitutive and an estradiol-inducible promoter in Arabidopsis thaliana to increase our understanding of the regulation of polyamine metabolism. Of particular interest was the role of the substrate ornithine not only in the regulation of polyamine biosynthesis, but also in...

  8. [Hyperammonemia due to ornithine transcarbamylase deficiency--a cause of lethal metabolic crisis during the newborn period and infancy (author's transl)].

    Science.gov (United States)

    Schuchmann, L; Colombo, J P; Fischer, H

    1980-05-01

    A severe hyperammonemia is the characteristic finding in patients with enzyme defects in urea cycle and one of the main causes of the acute metabolic crisis dsuring the newborn period and infancy. A case report is given about two male infants, who died in the age of one and of seven months respectively. In the second child the blood ammonia concentration raised up to 833 micrograms/100 ml, and, OTC deficiency was diagnosed due to enzyme determination in liver biopsie. Probably, the first child, that also died as newborn, suffered from the same disease. In this case, only post mortem findings are available.

  9. Role of ornithine decarboxylase in breast cancer

    Institute of Scientific and Technical Information of China (English)

    Wensheng Deng; Xian Jiang; Yu Mei; Jingzhong Sun; Rong Ma; Xianxi Liu; Hui Sun; Hui Tian; Xueying Sun

    2008-01-01

    Ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine biosynthesis that decarboxylates ornithine to putrescine, has become a promising target for cancer research. The aim of this study is to investigate the role of ODC in breast cancer. We detected expression of ODC in breast cancer tissues and four breast cancer cell lines, and transfected breast cancer cells with an adenoviral vector carrying antisense ODC (rAd-ODC/Ex3as) and examined their growth and migration.ODC was overexpressed in breast cancer tissues and cell lines compared with non-tumor tissues and normal breast epithelial celis,and there was a positive correlation between the level of ODC mRNA and the staging of tumors.The expression of ODC correlated with cyclin D1,a cell cycle protein,in synchronized breast cancer MDA-MB-231 cells.Gene transfection of rAd-ODC/Ex3as markedly down-regulated expression Of ODC and cyclin D1,resulting in suppression of proliferation and cell cycle arrest at G0-G1 phase,and the inhibifion of colony formation,an anchorage-independent growth pattern,and the migratory ability of MDA-MB-231 cells.rAd-ODC/Ex3as also markedly reduced the concentration of putrescine,but not spermidine or spermine,in MDA-MB-231 cells.The results suggested that the ODC gene might act as aprognostic factor for breast cancer and it could be a promising therapeutic target.

  10. Ornithine aminotransferase deficiency: Diagnostic difficulties in neonatal presentation

    NARCIS (Netherlands)

    Cleary, M. A.; Dorland, L.; de Koning, T. J.; Poll-The, B. T.; Duran, M.; Mandell, R.; Shih, V. E.; Berger, R.; Olpin, S. E.; Besley, G. T. N.

    2005-01-01

    We describe two unrelated cases of ornithine aminotransferase (OAT) deficiency with rare neonatal presentation of hyperammonaemia. The diagnosis in the neonatal presentation of OAT deficiency is hampered as hyperornithinaemia is absent. Enzyme and mutation studies confirmed the diagnosis. OAT

  11. Activities of arginine and ornithine decarboxylases in various plant species.

    Science.gov (United States)

    Birecka, H; Bitonti, A J; McCann, P P

    1985-10-01

    In extracts from the youngest leaves of Avena sativa, Hordeum vulgare, Zea Mays, Pisum sativum, Phaseolus vulgaris, Lactuca sativa, and four pyrrolizidine alkaloid-bearing species of Heliotropium, the activities of ornithine decarboxylase, close to V(max), ranged between traces and 1.5 nanomoles per hour per gram fresh weight when based on putrescine formed during incubation with labeled ornithine. The arginine decarboxylase activities in the same extracts ranged between 8 and 8000 nanomoles per hour per gram fresh weight being lowest in the borages and highest in oat and barley. alpha-Difluoromethylornithine and alpha-difluoromethylarginine inhibited ornithine and arginine decarboxylases, respectively, in all species. Agmatine, putrescine, spermidine, and spermine were found in all, diaminopropane in eight, and cadaverine in three species.No correlation was observed between arginine or ornithine decarboxylase level and the levels of total polyamines. The in vitro decarboxylase activities found in the borages cannot explain the high accumulation of putrescine-derived pyrrolizidines in their youngest leaves if the pyrrolizidines are produced in situ from arginine and/or ornithine as precursors; other possibilities are discussed.In assays of ornithine decarboxylase, an interference of decarboxylation not due to this enzyme was observed in extracts from all species. In arginine decarboxylase assays, the interfering decarboxylation as well as the interference of arginase were apparent in two species. Addition of aminoguanidine was needed to suppress oxidative degradation of putrescine and agmatine during incubation of extracts from pea, bean, lettuce, Heliotropium angiospermum, and Heliotropium indicum.

  12. Glutamine and ornithine alpha-ketoglutarate supplementation on malate dehydrogenases expression in hepatectomized rats

    OpenAIRE

    Guimarães Filho, Artur; Cunha, Rodrigo Maranguape Silva da; Vasconcelos, Paulo Roberto Leitão de; Guimarães, Sergio Botelho

    2014-01-01

    PURPOSE: To evaluate the relative gene expression (RGE) of cytosolic (MDH1) and mitochondrial (MDH2) malate dehydrogenases enzymes in partially hepatectomized rats after glutamine (GLN) or ornithine alpha-ketoglutarate (OKG) suplementation. METHODS: One-hundred and eight male Wistar rats were randomly distributed into six groups (n=18): CCaL, GLNL and OKGL and fed calcium caseinate (CCa), GLN and OKG, 0.5g/Kg by gavage, 30 minutes before laparotomy. CCaH, GLNH and OKGH groups were likewise fe...

  13. Ornithine decarboxylase, polyamines, and pyrrolizidine alkaloids in senecio and crotalaria.

    Science.gov (United States)

    Birecka, H; Birecki, M; Cohen, E J; Bitonti, A J; McCann, P P

    1988-01-01

    When tested for ornithine and arginine decarboxylases, pyrrolizidine alkaloid-bearing Senecio riddellii, S. longilobus (Compositae), and Crotalaria retusa (Leguminosae) plants exhibited only ornithine decarboxylase activity. This contrasts with previous studies of four species of pyrrolizidine alkaloid-bearing Heliotropium (Boraginaceae) in which arginine decarboxylase activity was very high relative to that of ornithine decarboxylase. Unlike Heliotropium angiospermum and Heliotropium indicum, in which endogenous arginine was the only detectable precursor of putrescine channeled into pyrrolizidines, in the species studied here-using difluoromethylornithine and difluoromethylarginine as the enzyme inhibitors-endogenous ornithine was the main if not the only precursor of putrescine converted into the alkaloid aminoalcohol moiety. In S. riddellii and C. retusa at flowering, ornithine decarboxylase activity was present mainly in leaves, especially the young ones. However, other very young organs such as inflorescence and growing roots exhibited much lower or very low activities; the enzyme activity in stems was negligible. There was no correlation between the enzyme activity and polyamine or alkaloid content in either species. In both species only free polyamines were detected except for C. retusa roots and inflorescence-with relatively very high levels of these compounds-in which conjugated putrescine, spermidine, and spermine were also found; agmatine was not identified by HPLC in any plant organ except for C. retusa roots with rhizobial nodules. Organ- or age-dependent differences in the polyamine levels were small or insignificant. The highest alkaloid contents were found in young leaves and inflorescence.

  14. L-ornithine-L-aspartate infusion efficacy in hepatic encephalopathy

    International Nuclear Information System (INIS)

    Ahmad, I.

    2008-01-01

    To determine the efficacy of L-ornithine-L-aspartate in treatment of hepatic encephalopathy. Cirrhotic patients with hyperammonemia and overt hepatic encephalopathy were enrolled. Eighty patients were randomized to two treatment groups, L-ornithine-L-aspartate (20g/d) or placebo, both dissolved in 250mL of 5% dextrose water and infused intravenously for four hours a day for five consecutive days with 0.5 g/kg dietary protein intake at the end of daily treatment period. Outcome variables were postprandial blood ammonia and mental state grade. Adverse reactions and mortality were also determined. Both treatment groups were comparable regarding age, gender, etiology of cirrhosis, Child-Pugh class, mental state grade and blood ammonia at baseline. Although, improvement occurred in both groups, there was a greater improvement in L-ornithine-L-aspartate group with regard to both variables. Four patients in the placebo group and 2 in L-ornithine-L-aspartate group died. L-ornithine-L-aspartate infusions were found to be effective in cirrhotic patients with hepatic encephalopathy. (author)

  15. Ornithine carbamoyltransferase from Spinacea oleracea: purification and characterization

    Czech Academy of Sciences Publication Activity Database

    Bellocco, E.; Di Salvo, C.; Lagana, G.; Galtieri, A.; Ficarra, S.; Kotyk, Arnošt; Leuzzi, U.

    2002-01-01

    Roč. 45, č. 4 (2002), s. 533-538 ISSN 0006-3134 Institutional research plan: CEZ:AV0Z5011922 Keywords : ornithine carbomoyltransferase * Spinacea oleracea Subject RIV: BE - Theoretical Physics Impact factor: 0.583, year: 2002

  16. Role of polyols in thermal inactivation of shark ornithine transcarbamoylase

    Czech Academy of Sciences Publication Activity Database

    Bellocco, E.; Lagana, G.; Barreca, D.; Ficarra, S.; Tellone, E.; Magazu, S.; Branca, C.; Kotyk, Arnošt; Galtieri, A.; Leuzzi, U.

    2005-01-01

    Roč. 54, č. 4 (2005), s. 395-402 ISSN 0862-8408 Institutional research plan: CEZ:AV0Z5011922 Keywords : ornithine transcarbamoylase * thermal inactivation * shark enzyme Subject RIV: CE - Biochemistry Impact factor: 1.806, year: 2005

  17. Altered subcellular localization of ornithine decarboxylase in Alzheimer's disease brain

    DEFF Research Database (Denmark)

    Nilsson, Tatjana; Bogdanovic, Nenad; Volkman, Inga

    2006-01-01

    The amyloid precursor protein can through ligand-mimicking induce expression of ornithine decarboxylase (ODC), the initial and rate-limiting enzyme in polyamine biosynthesis. We report here the regional distribution and cellular localization of ODC immunoreactivity in Alzheimer's disease (AD...

  18. Enzyme activity and allosteric characteristics of gamma-irradiated solid aspartate transcarbamylase

    International Nuclear Information System (INIS)

    Bigler, W.N.; Tolbert, B.M.

    1977-01-01

    Aspartate transcarbamylase purified from E. coli was lyophilized, irradiated in vacuo with γ radiation from a cesium-137 source, redissolved in buffer under a nitrogen atmosphere, and assayed for enzyme activity. Lyophilized and redissolved enzyme had normal catalytic and allosteric kinetic characteristics. The average D 37 observed with saturating substrate, 25 mM aspartate, was 4.1 Mrad. With less than saturating substrate, 5 mM aspartate, the activity increases from zero to 1.6 Mrad and then decreases with a D 37 of 7.2 Mrad. Inclusion of 1 mM CTP, an allosteric inhibitor, in the 5 mM aspartate assays results in a more pronounced maximum in the activity curve occurring at slightly higher dose, 2.2 Mrad. Inhibitability by CTP has a D 37 of 2.3 Mrad with doses below the activity maximum. Enzyme lyophilized in the presence of 1 mM CTP has a D 37 of 2.9 Mrad. ATCase activity changes caused by irradiation of lyophylized bacteria were qualitatively like the changes observed in the detailed studies with the purified enzyme. Apparent radiation sensitivities of ATCase in lyophilized bacteria were observed to vary with the technique used to disrupt the resuspended bacteria

  19. Urease Inhibitor Drug Treatment for Urea Cycle Disorders

    Science.gov (United States)

    2016-08-23

    Ornithine Transcarbamylase Deficiency; Argininosuccinate Synthetase Deficiency (Citrullinemia); Argininosuccinic Acid Lyase Deficiency (Argininosuccinic Aciduria); Carbamyl-Phosphate Synthase I Deficiency

  20. Improved L-ornithine production in Corynebacterium crenatum by introducing an artificial linear transacetylation pathway.

    Science.gov (United States)

    Shu, Qunfeng; Xu, Meijuan; Li, Jing; Yang, Taowei; Zhang, Xian; Xu, Zhenghong; Rao, Zhiming

    2018-05-04

    L-Ornithine is a non-protein amino acid with extensive applications in the food and pharmaceutical industries. In this study, we performed metabolic pathway engineering of an L-arginine hyper-producing strain of Corynebacterium crenatum for L-ornithine production. First, we amplified the L-ornithine biosynthetic pathway flux by blocking the competing branch of the pathway. To enhance L-ornithine synthesis, we performed site-directed mutagenesis of the ornithine-binding sites to solve the problem of L-ornithine feedback inhibition for ornithine acetyltransferase. Alternatively, the genes argA from Escherichia coli and argE from Serratia marcescens, encoding the enzymes N-acetyl glutamate synthase and N-acetyl-L-ornithine deacetylase, respectively, were introduced into Corynebacterium crenatum to mimic the linear pathway of L-ornithine biosynthesis. Fermentation of the resulting strain in a 5-L bioreactor allowed a dramatically increased production of L-ornithine, 40.4 g/L, with an overall productivity of 0.673 g/L/h over 60 h. This demonstrates that an increased level of transacetylation is beneficial for L-ornithine biosynthesis.

  1. L-ornithine derived polyamines in cystic fibrosis airways.

    Directory of Open Access Journals (Sweden)

    Hartmut Grasemann

    Full Text Available Increased arginase activity contributes to airway nitric oxide (NO deficiency in cystic fibrosis (CF. Whether down-stream products of arginase activity contribute to CF lung disease is currently unknown. The objective of this study was to test whether L-ornithine derived polyamines are present in CF airways and contribute to airway pathophysiology. Polyamine concentrations were measured in sputum of patients with CF and in healthy controls, using liquid chromatography-tandem mass spectrometry. The effect of spermine on airway smooth muscle mechanical properties was assessed in bronchial segments of murine airways, using a wire myograph. Sputum polyamine concentrations in stable CF patients were similar to healthy controls for putrescine and spermidine but significantly higher for spermine. Pulmonary exacerbations were associated with an increase in sputum and spermine levels. Treatment for pulmonary exacerbations resulted in decreases in arginase activity, L-ornithine and spermine concentrations in sputum. The changes in sputum spermine with treatment correlated significantly with changes in L-ornithine but not with sputum inflammatory markers. Incubation of mouse bronchi with spermine resulted in an increase in acetylcholine-induced force and significantly reduced nitric oxide-induced bronchial relaxation. The polyamine spermine is increased in CF airways. Spermine contributes to airways obstruction by reducing the NO-mediated smooth muscle relaxation.

  2. Effect of ornithine on ammonia utilization and urea synthesis in isolated hepatocytes from fed rats

    International Nuclear Information System (INIS)

    Garwacki, S.; Wiechetek, M.; Souffrant, W.B.

    1988-01-01

    The effect of ornithine on the ammonia utilization and urea synthesis in hepatocytes isolated from fed male Wistar rats was investigated. On the basis of the 15 N tracer technique, it was found that ornithine stimulated urea synthesis with an increased utilization of the exogenously marked ammonia for urea, but deminished its utilization in other N-metabolic processes. The results also showed that the stimulation of urea synthesis due to ornithine resulted from the utilization of both exogenous and endogenous sources. (author)

  3. Spectroscopic and thermodynamic properties of L-ornithine monohydrochloride

    Energy Technology Data Exchange (ETDEWEB)

    Raja, M. Dinesh [Department of Physics, Bharath University, Chennai – 600073 (India); Kumar, C. Maria Ashok; Arulmozhi, S.; Madhavan, J., E-mail: jmadhavang@yahoo.com [Department of Physics, Loyola College, Chennai – 600034 (India)

    2015-06-24

    L-Ornithine Monohydrochloride (LOMHCL) has been investigated with the help of B3LYP density functional theory with 6-31 G (d, p) basis set. Fourier transform infrared and Fourier transform Raman spectra is to identify the various functional groups. The theoretical frequencies showed very good agreement with experimental values. On the basis of the thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations between standard heat capacities (C) standard entropies (S), and standard enthalpy changes (H) and temperatures. Second harmonic generation (SHG) efficiency of the grown crystal has been studied.

  4. Retinoic acid modulation of ultraviolet light-induced epidermal ornithine decarboxylase activity

    International Nuclear Information System (INIS)

    Lowe, N.J.; Breeding, J.

    1982-01-01

    Irradiation of skin with ultraviolet light of sunburn range (UVB) leads to a large and rapid induction of the polyamine biosynthetic enzyme ornithine decarboxylase in the epidermis. Induction of epidermal ornithine decarboxylase also occurs following application of the tumor promoting agent 12-0-tetradecanoylphorbol-13 acetate and topical retinoic acid is able to block both this ornithine decarboxylase induction and skin tumor promotion. In the studies described below, topical application of retinoic acid to hairless mouse skin leads to a significant inhibition of UVB-induced epidermal ornithine decarboxylase activity. The degree of this inhibition was dependent on the dose, timing, and frequency of the application of retinoic acid. To show significant inhibition of UVB-induced ornithine decarboxylase the retinoic acid had to be applied within 5 hr of UVB irradiation. If retinoic acid treatment was delayed beyond 7 hr following UVB, then no inhibition of UVB-induced ornithine decarboxylase was observed. The quantities of retinoic acid used (1.7 nmol and 3.4 nmol) have been shown effective at inhibiting 12-0-tetradecanoyl phorbol-13 acetate induced ornithine decarboxylase. The results show that these concentrations of topical retinoic acid applied either before or immediately following UVB irradiation reduces the UVB induction of epidermal ornithine decarboxylase. The effect of retinoic acid in these regimens on UVB-induced skin carcinogenesis is currently under study

  5. Interorgan metabolism of ornithine phenylacetate (OP)-A novel strategy for treatment of hyperammonemia

    DEFF Research Database (Denmark)

    Dadsetan, Sherry; Sørensen, Michael; Bak, Lasse Kristoffer

    2013-01-01

    Combined administration of ornithine and phenylacetate (OP) is proposed as a novel treatment of hyperammonemia and hepatic encephalopathy. Ornithine is believed to increase ammonia fixation into glutamine in muscle tissue and glutamine is subsequently thought to react with phenylacetate forming......, skeletal muscle, liver and kidney. In BDL rats, OP treatment reduced arterial ammonia concentration and increased that of glutamine 30min after the treatment but not after 15h. OP treatment did not increase (15)N labeling in glutamine from [2,5-(15)N]ornithine and (15)NH(4)(+) in skeletal muscle or liver....... However, the extent of glutamine labeling from [2,5-(15)N]ornithine or (15)NH(4)(+) was similar in arterial blood and liver and higher than that in skeletal muscle. These findings suggest that the effect of OP was related to hepatic metabolism of ornithine. PAGN could not be detected in urine or blood...

  6. AmcA - a putative mitochondrial ornithine transporter supporting fungal siderophore biosynthesis

    Directory of Open Access Journals (Sweden)

    Lukas eSchafferer

    2015-04-01

    Full Text Available Iron is an essential nutrient required for a wide range of cellular processes. The opportunistic fungal pathogen Aspergillus fumigatus employs low-molecular mass iron-specific chelators, termed siderophores, for uptake, storage and intracellular iron distribution, which play a crucial role in the pathogenicity of this fungus. Siderophore biosynthesis depends on coordination with the supply of its precursor ornithine, produced mitochondrially from glutamate or cytosolically via hydrolysis of arginine. In this study, we demonstrate a role of the putative mitochondrial transporter AmcA (AFUA_8G02760 in siderophore biosynthesis of A. fumigatus.Consistent with a role in cellular ornithine handling, AmcA-deficiency resulted in decreased cellular ornithine and arginine contents as well as decreased siderophore production on medium containing glutamine as the sole nitrogen source. In support, arginine and ornithine as nitrogen sources did not impact siderophore biosynthesis due to cytosolic ornithine availability. As revealed by Northern blot analysis, transcript levels of siderophore biosynthetic genes were unresponsive to the cellular ornithine level. In contrast to siderophore production, AmcA deficiency did only mildly decrease the cellular polyamine content, demonstrating cellular prioritization of ornithine use. Nevertheless, AmcA-deficiency increased the susceptibility of A. fumigatus to the polyamine biosynthesis inhibitor eflornithine, most likely due to the decreased ornithine pool. AmcA-deficiency decreased the growth rate particularly on ornithine as the sole nitrogen source during iron starvation and sufficiency, indicating an additional role in the metabolism and fitness of A. fumigatus, possibly in mitochondrial ornithine import. In the Galleria mellonella infection model, AmcA-deficiency did not affect virulence of A. fumigatus, most likely due to the residual siderophore production and arginine availability in this host niche.

  7. Glutamine and ornithine alpha-ketoglutarate supplementation on malate dehydrogenases expression in hepatectomized rats.

    Science.gov (United States)

    Guimarães Filho, Artur; Cunha, Rodrigo Maranguape Silva da; Vasconcelos, Paulo Roberto Leitão de; Guimarães, Sergio Botelho

    2014-06-01

    To evaluate the relative gene expression (RGE) of cytosolic (MDH1) and mitochondrial (MDH2) malate dehydrogenases enzymes in partially hepatectomized rats after glutamine (GLN) or ornithine alpha-ketoglutarate (OKG) suplementation. One-hundred and eight male Wistar rats were randomly distributed into six groups (n=18): CCaL, GLNL and OKGL and fed calcium caseinate (CCa), GLN and OKG, 0.5 g/Kg by gavage, 30 minutes before laparotomy. CCaH, GLNH and OKGH groups were likewise fed 30 minutes before 70% partial hepatectomy. Blood and liver samples were collected three, seven and 14 days after laparotomy/hepatectomy for quantification of MDH1/MDH2 enzymes using the real-time polymerase chain reaction (PCR) methodology. Relative enzymes expression was calculated by the 2-(ΔΔC)T method using the threshold cycle (CT) value for normalization. MDH1/MDH2 RGE was not different in hepatectomized rats treated with OKG compared to rats treated with CCa. However, MDH1/MDH2 RGE was greater on days 3 (321:1/26.48:1) and 7 (2.12:1/2.48:1) while MDH2 RGE was greater on day 14 (7.79:1) in hepatectomized rats treated with GLN compared to control animals. Glutamine has beneficial effects in liver regeneration in rats by promoting an up-regulation of the MDH1 and MDH2 relative gene expression.

  8. Randomised controlled trial of the effects of L-ornithine on stress markers and sleep quality in healthy workers

    OpenAIRE

    Miyake, Mika; Kirisako, Takayoshi; Kokubo, Takeshi; Miura, Yutaka; Morishita, Koji; Okamura, Hisayoshi; Tsuda, Akira

    2014-01-01

    Background L-ornithine is a non-essential, non-protein amino acid. Although L-ornithine is contained in various foods, the amount is usually small. Recently, studies have shown that orally administered L-ornithine reduced the stress response in animals. From these findings, we speculated that L-ornithine may play a role in the relieve of stress and improve sleep and fatigue symptoms in humans. Through a randomised, double-blind, placebo-controlled clinical study, we asked if L-ornithine could...

  9. The Combined Effect of Caffeine and Ornithine on the Mood of Healthy Office Workers

    Science.gov (United States)

    Misaizu, Akane; Kokubo, Takeshi; Tazumi, Kyoko; Kanayama, Masaya; Miura, Yutaka

    2014-01-01

    Caffeine is widely consumed and well known for stimulating the central nervous system. When developing new foods and beverages that contain caffeine, it is important to explore the potential synergistic effects of consuming amino acids and other food ingredients with caffeine on humans. Given the physiological pathways affected by the amino acid ornithine, consumption of ornithine with caffeine may have synergistic effects. The purpose of the present study was to examine the effect of consuming caffeine with ornithine in humans. The study used a randomized, placebo-controlled, double-blinded crossover design. The subjects were all healthy office workers who ingested the placebo, 100 mg caffeine, or 100 mg caffeine plus 200 mg ornithine in the morning and completed questionnaires about their mood. Office workers who consumed the combination of caffeine and ornithine had higher mood ratings 8 h after consumption than office workers who consumed caffeine alone. The results of the present study suggest that there is a unique synergistic effect between caffeine and ornithine on the mood of healthy office workers and that ornithine may potentiate the effects of caffeine. PMID:25580405

  10. Altered subcellular localization of ornithine decarboxylase in Alzheimer's disease brain

    International Nuclear Information System (INIS)

    Nilsson, Tatjana; Bogdanovic, Nenad; Volkman, Inga; Winblad, Bengt; Folkesson, Ronnie; Benedikz, Eirikur

    2006-01-01

    The amyloid precursor protein can through ligand-mimicking induce expression of ornithine decarboxylase (ODC), the initial and rate-limiting enzyme in polyamine biosynthesis. We report here the regional distribution and cellular localization of ODC immunoreactivity in Alzheimer's disease (AD) brains. In frontal cortex and hippocampus of control cases, the most pronounced ODC immunoreactivity was found in the nucleus. In possible and definite AD the immunoreactivity had shifted to the cytoplasm. In cerebellum of control cases, ODC staining was found in a small portion of Purkinje cells, mostly in the nucleus. In AD, both possible and definite, the number of stained Purkinje cells increased significantly and immunoreactivity was shifted to the cytoplasm, even though it was still prominent in the nucleus. In conclusion, our study reveals an early shift of the ODC immunoreactivity in AD from the nuclear compartment towards the cytoplasm

  11. Characterization of the Ornithine Hydroxylation Step in Albachelin Biosynthesis

    Directory of Open Access Journals (Sweden)

    Kendra Bufkin

    2017-10-01

    Full Text Available N-Hydroxylating monooxygenases (NMOs are involved in siderophore biosynthesis. Siderophores are high affinity iron chelators composed of catechol and hydroxamate functional groups that are synthesized and secreted by microorganisms and plants. Recently, a new siderophore named albachelin was isolated from a culture of Amycolatopsis alba growing under iron-limiting conditions. This work focuses on the expression, purification, and characterization of the NMO, abachelin monooxygenase (AMO from A. alba. This enzyme was purified and characterized in its holo (FAD-bound and apo (FAD-free forms. The apo-AMO could be reconstituted by addition of free FAD. The two forms of AMO hydroxylate ornithine, while lysine increases oxidase activity but is not hydroxylated and display low affinity for NADPH.

  12. An endosymbiont positively modulates ornithine decarboxylase in host trypanosomatids

    International Nuclear Information System (INIS)

    Frossard, Mariana Lins; Seabra, Sergio Henrique; Matta, Renato Augusto da; Souza, Wanderley de; Garcia de Mello, Fernando; Motta, Maria Cristina Machado

    2006-01-01

    Summary: Some trypanosomatids, such as Crithidia deanei, are endosymbiont-containing species. Aposymbiotic strains are obtained after antibiotic treatment, revealing interesting aspects of this symbiotic association. Ornithine decarboxylase (ODC) promotes polyamine biosynthesis and contributes to cell proliferation. Here, we show that ODC activity is higher in endosymbiont-bearing trypanosomatids than in aposymbiotic cells, but isolated endosymbionts did not display this enzyme activity. Intriguingly, expressed levels of ODC were similar in both strains, suggesting that ODC is positively modulated in endosymbiont-bearing cells. When the aposymbiotic strain was grown in conditioned medium, obtained after cultivation of the endosymbiont-bearing strain, cellular proliferation as well as ODC activity and localization were similar to that observed in the endosymbiont-containing trypanosomatids. Furthermore, dialyzed-heated medium and trypsin treatment reduced ODC activity of the aposymbiont strain. Taken together, these data indicate that the endosymbiont can enhance the protozoan ODC activity by providing factors of protein nature, which increase the host polyamine metabolism

  13. Improved tolerance of abdominal large-volume radiotherapy due to ornithine aspartate

    International Nuclear Information System (INIS)

    Kuttig, H.

    1983-01-01

    The influence of ornithine aspartate on supporting the hepatic function was investigated in a group of 47 patients with tumour dissemination in the pelvic and abdominal region, randomised on the basis of the progress of the serum enzymes GOT, GPT, LAD, LDH, LAP and the alkaline phosphatase during and following completion of a course of large-volume radiotherapy. The adjuvant therapy with ornithine aspartate resulted in reduced enzyme movement with an earlier tendency to normalisation. The results, which are borne out by statistics, clearly show an improvement in the hepatic function on detoxication of toxic degradation products of radiotherapy with reduced impairment of the body's own defence mechanisms. Subjectively too, the course of treatment with ornithine aspartate showed a reduced ratio of side effects as regards lassitude and impairment of the patient's general well-being as compared with the group of patients to whom ornithine aspartate was not simultaneously administered. (orig.) [de

  14. Functional characterization of an ornithine cyclodeaminase-like protein of Arabidopsis thaliana

    OpenAIRE

    Sharma, Sandeep; Shinde, Suhas; Verslues, Paul E

    2013-01-01

    Background In plants, proline synthesis occurs by two enzymatic steps starting from glutamate as a precursor. Some bacteria, including bacteria such as Agrobacterium rhizogenes have an Ornithine Cyclodeaminase (OCD) which can synthesize proline in a single step by deamination of ornithine. In A. rhizogenes, OCD is one of the genes transferred to the plant genome during the transformation process and plants expressing A. rhizogenes OCD have developmental phenotypes. One nuclear encoded gene of...

  15. Activities of Arginine and Ornithine Decarboxylases in Various Plant Species 1

    Science.gov (United States)

    Birecka, Helena; Bitonti, Alan J.; McCann, Peter P.

    1985-01-01

    In extracts from the youngest leaves of Avena sativa, Hordeum vulgare, Zea Mays, Pisum sativum, Phaseolus vulgaris, Lactuca sativa, and four pyrrolizidine alkaloid-bearing species of Heliotropium, the activities of ornithine decarboxylase, close to Vmax, ranged between traces and 1.5 nanomoles per hour per gram fresh weight when based on putrescine formed during incubation with labeled ornithine. The arginine decarboxylase activities in the same extracts ranged between 8 and 8000 nanomoles per hour per gram fresh weight being lowest in the borages and highest in oat and barley. α-Difluoromethylornithine and α-difluoromethylarginine inhibited ornithine and arginine decarboxylases, respectively, in all species. Agmatine, putrescine, spermidine, and spermine were found in all, diaminopropane in eight, and cadaverine in three species. No correlation was observed between arginine or ornithine decarboxylase level and the levels of total polyamines. The in vitro decarboxylase activities found in the borages cannot explain the high accumulation of putrescine-derived pyrrolizidines in their youngest leaves if the pyrrolizidines are produced in situ from arginine and/or ornithine as precursors; other possibilities are discussed. In assays of ornithine decarboxylase, an interference of decarboxylation not due to this enzyme was observed in extracts from all species. In arginine decarboxylase assays, the interfering decarboxylation as well as the interference of arginase were apparent in two species. Addition of aminoguanidine was needed to suppress oxidative degradation of putrescine and agmatine during incubation of extracts from pea, bean, lettuce, Heliotropium angiospermum, and Heliotropium indicum. PMID:16664442

  16. Central L-ornithine, but not polyamines, induces a hypnotic effect in neonatal chicks under acute stress.

    Science.gov (United States)

    Kurauchi, Isao; Shigemi, Kazutaka; Kabuki, Yusuke; Hamasu, Kousuke; Yamane, Haruka; Aoki, Mami; Kawada, Yoko; Morishita, Koji; Denbow, D Michael; Furuse, Mitsuhiro

    2010-02-01

    To clarify whether L-ornithine and/or its metabolite involves sedative and hypnotic effects under social separation stress, the effects of intracerebroventricular (i.c.v.) injection of L-ornithine and polyamines (putrescine, spermidine and spermine) were compared in chicks. Birds were injected i.c.v. with 0.5 mumol of L-ornithine, putrescine, spermidine, spermine or saline (control). After injection, chicks were immediately separated from the flock and monitored for the number of distress vocalizations and various postures. L-Ornithine greatly attenuated the stress response and caused sedative and hypnotic effects. Among the polyamines, only putrescine attenuated distress vocalizations but did not induce sleep. In conclusion, the sedative and hypnotic effect of L-ornithine was mainly induced by L-ornithine itself, while the polyamines contributed to the sedative, but not hypnotic, effect under social separation stress.

  17. Ultraviolet radiation induction of ornithine decarboxylase in rat keratinocytes

    International Nuclear Information System (INIS)

    Rosen, C.F.; Gajic, D.; Drucker, D.J.

    1990-01-01

    UV radiation plays an important role in the induction of cutaneous malignancy, including basal cell and squamous cell carcinomas and malignant melanoma. In addition to its effects on DNA damage and repair mechanisms, UV radiation has been shown to modulate the expression of specific genes, altering the levels of their mRNAs and the synthesis of their corresponding proteins. In order to gain further information about the molecular effects of UV radiation, we have studied the regulation of ornithine decarboxylase (ODC) gene expression in response to UVB radiation. ODC is the rate-limiting enzyme in polyamine biosynthesis, is involved in growth and differentiation, and has been implicated in carcinogenesis. Keratinocytes grown in culture were either sham-irradiated or exposed to increasing doses of UVB (1-5 mJ/cm2). Northern blot analysis of keratinocyte RNA under basal conditions demonstrated the presence of two ODC mRNA transcripts. Increasing exposure to UVB resulted in a dose-dependent increase in the levels of both ODC mRNA transcripts. The induction of ODC gene expression following UVB was noted 2 h after UVB exposure, and ODC mRNA levels continued to increase up to 24 h after UVB exposure. The UVB-induced increase in ODC gene expression was not serum dependent, despite the ability of serum alone to induce ODC gene expression. The mRNA transcripts for actin and hexosaminidase A were not induced after UVB exposure. These studies show that the UVB-induced increase in ODC activity is due, at least in part, to an increase in ODC gene expression and they provide a useful model for the analysis of the molecular effects of UVB radiation

  18. Ultraviolet radiation induction of ornithine decarboxylase in rat keratinocytes

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, C.F.; Gajic, D.; Drucker, D.J. (Women' s College Hospital, Toronto, Ontario (Canada))

    1990-05-01

    UV radiation plays an important role in the induction of cutaneous malignancy, including basal cell and squamous cell carcinomas and malignant melanoma. In addition to its effects on DNA damage and repair mechanisms, UV radiation has been shown to modulate the expression of specific genes, altering the levels of their mRNAs and the synthesis of their corresponding proteins. In order to gain further information about the molecular effects of UV radiation, we have studied the regulation of ornithine decarboxylase (ODC) gene expression in response to UVB radiation. ODC is the rate-limiting enzyme in polyamine biosynthesis, is involved in growth and differentiation, and has been implicated in carcinogenesis. Keratinocytes grown in culture were either sham-irradiated or exposed to increasing doses of UVB (1-5 mJ/cm2). Northern blot analysis of keratinocyte RNA under basal conditions demonstrated the presence of two ODC mRNA transcripts. Increasing exposure to UVB resulted in a dose-dependent increase in the levels of both ODC mRNA transcripts. The induction of ODC gene expression following UVB was noted 2 h after UVB exposure, and ODC mRNA levels continued to increase up to 24 h after UVB exposure. The UVB-induced increase in ODC gene expression was not serum dependent, despite the ability of serum alone to induce ODC gene expression. The mRNA transcripts for actin and hexosaminidase A were not induced after UVB exposure. These studies show that the UVB-induced increase in ODC activity is due, at least in part, to an increase in ODC gene expression and they provide a useful model for the analysis of the molecular effects of UVB radiation.

  19. Mechanism of gene transfection by polyamidoamine (PAMAM) dendrimers modified with ornithine residues.

    Science.gov (United States)

    Kumar, Ajay; Yellepeddi, Venkata K; Vangara, Kiran K; Strychar, Kevin B; Palakurthi, Srinath

    2011-11-01

    The aim of this study was to prepare and investigate the mechanism of uptake of the dendriplexes prepared with ornithine-conjugated polyamidoamine (PAMAM) G4 dendrimers. Ornithine-conjugated PAMAMG4 dendrimers were prepared by Fmoc synthesis. A comparative transfection study in NCI H157G cells and polyamine transport-deficient cell line NCI H157R was performed to confirm the role of the polyamine transporter system (PAT) in the dendriplex uptake. Transfection efficiency significantly increased with increase in generation number and extent of ornithine conjugation. Transfection efficiency of the PAMAMG4-ORN60 dendrimers significantly decreased in presence of excess of ornithine (P dendrimers. Transfection efficiency of PAMAMG4-ORN60 was significantly low in NCI H157R (31.66 ± 3.95%, RFU: 17.87 ± 1.34) as compared to NCI H157G cell line (63.07 ± 6.8%, relative fluorescence units (RFU): 23.28 ± 0.66). Results indicate the role of PAT in addition to charge-mediated endocytosis in the internalization of ornithine-conjugated PAMAMG4 dendrimers. Cytotoxicity analysis (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay) in human embryonic kidney cell line (HEK) 293T cells showed that the dendriplexes were non-toxic at N/P 10.

  20. Exploitation of the Ornithine Effect Enhances Characterization of Stapled and Cyclic Peptides

    Science.gov (United States)

    Crittenden, Christopher M.; Parker, W. Ryan; Jenner, Zachary B.; Bruns, Kerry A.; Akin, Lucas D.; McGee, William M.; Ciccimaro, Eugene; Brodbelt, Jennifer S.

    2016-05-01

    A method to facilitate the characterization of stapled or cyclic peptides is reported via an arginine-selective derivatization strategy coupled with MS/MS analysis. Arginine residues are converted to ornithine residues through a deguanidination reaction that installs a highly selectively cleavable site in peptides. Upon activation by CID or UVPD, the ornithine residue cyclizes to promote cleavage of the adjacent amide bond. This Arg-specific process offers a unique strategy for site-selective ring opening of stapled and cyclic peptides. Upon activation of each derivatized peptide, site-specific backbone cleavage at the ornithine residue results in two complementary products: the lactam ring-containing portion of the peptide and the amine-containing portion. The deguanidination process not only provides a specific marker site that initiates fragmentation of the peptide but also offers a means to unlock the staple and differentiate isobaric stapled peptides.

  1. Aspergillus fumigatus SidA is a highly specific ornithine hydroxylase with bound flavin cofactor.

    Science.gov (United States)

    Chocklett, Samuel W; Sobrado, Pablo

    2010-08-10

    Ferrichrome is a hydroxamate-containing siderophore produced by the pathogenic fungus Aspergillus fumigatus under iron-limiting conditions. This siderophore contains N(5)-hydroxylated l-ornithines essential for iron binding. A. fumigatus siderophore A (Af SidA) catalyzes the flavin- and NADPH-dependent hydroxylation of l-ornithine in ferrichrome biosynthesis. Af SidA was recombinantly expressed and purified as a soluble tetramer and is the first member of this class of flavin monooxygenases to be isolated with a bound flavin cofactor. The enzyme showed typical saturation kinetics with respect to l-ornithine while substrate inhibition was observed at high concentrations of NADPH and NADH. Increasing amounts of hydrogen peroxide were measured as a function of reduced nicotinamide coenzyme concentration, indicating that inhibition was caused by increased uncoupling. Af SidA is highly specific for its amino acid substrate, only hydroxylating l-ornithine. An 8-fold preference in the catalytic efficiency was determined for NADPH compared to NADH. In the absence of substrate, Af SidA can be reduced by NADPH, and a C4a-(hydro)peroxyflavin intermediate is observed. The decay of this intermediate is accelerated by l-ornithine binding. This intermediate was only stabilized by NADPH and not by NADH, suggesting a role for NADP(+) in the stabilization of intermediates in the reaction of Af SidA. NADP(+) is a competitive inhibitor with respect to NADPH, demonstrating that Af SidA forms a ternary complex with NADP(+) and l-ornithine during catalysis. The data suggest that Af SidA likely proceeds by a sequential kinetic mechanism.

  2. Ornithine Decarboxylase Activity Is Required for Prostatic Budding in the Developing Mouse Prostate.

    Directory of Open Access Journals (Sweden)

    Melissa Gamat

    Full Text Available The prostate is a male accessory sex gland that produces secretions in seminal fluid to facilitate fertilization. Prostate secretory function is dependent on androgens, although the mechanism by which androgens exert their effects is still unclear. Polyamines are small cationic molecules that play pivotal roles in DNA transcription, translation and gene regulation. The rate-limiting enzyme in polyamine biosynthesis is ornithine decarboxylase, which is encoded by the gene Odc1. Ornithine decarboxylase mRNA decreases in the prostate upon castration and increases upon administration of androgens. Furthermore, testosterone administered to castrated male mice restores prostate secretory activity, whereas administering testosterone and the ornithine decarboxylase inhibitor D,L-α-difluromethylornithine (DFMO to castrated males does not restore prostate secretory activity, suggesting that polyamines are required for androgens to exert their effects. To date, no one has examined polyamines in prostate development, which is also androgen dependent. In this study, we showed that ornithine decarboxylase protein was expressed in the epithelium of the ventral, dorsolateral and anterior lobes of the adult mouse prostate. Ornithine decarboxylase protein was also expressed in the urogenital sinus (UGS epithelium of the male and female embryo prior to prostate development, and expression continued in prostatic epithelial buds as they emerged from the UGS. Inhibiting ornithine decarboxylase using DFMO in UGS organ culture blocked the induction of prostatic buds by androgens, and significantly decreased expression of key prostate transcription factor, Nkx3.1, by androgens. DFMO also significantly decreased the expression of developmental regulatory gene Notch1. Other genes implicated in prostatic development including Sox9, Wif1 and Srd5a2 were unaffected by DFMO. Together these results indicate that Odc1 and polyamines are required for androgens to exert their

  3. Action of ornithine alpha-ketoglutarate, ornithine hydrochloride, and calcium alpha-ketoglutarate on plasma amino acid and hormonal patterns in healthy subjects.

    Science.gov (United States)

    Cynober, L; Coudray-Lucas, C; de Bandt, J P; Guéchot, J; Aussel, C; Salvucci, M; Giboudeau, J

    1990-02-01

    Ornithine alpha-ketoglutarate (OKG) has been useful as an adjuvant of enteral and parenteral nutrition. However, its metabolism and mechanism of action remain unclear although it is known that alpha-ketoglutarate (alpha KG) and ornithine (ORN) follow, in part, common metabolic pathways. Six fasting healthy male subjects underwent three separate oral load tests: (i) they received 10 g of OKG (i.e., 3.6 g of alpha KG and 6.4 g of ORN); (ii) 6.4 g of ORN as ornithine hydrochloride, and (iii) 3.6 g of alpha KG as calcium alpha-ketoglutarate. Blood was drawn 15 times over a five-hour period for measurements of plasma amino acids, alpha KG, insulin, and glucagon. After OKG and ORN administration, plasma ORN peaked at 60-75 min (494 +/- 91 and 541 +/- 85 mumol/L). The increase in plasma alpha KG was very small. OKG, alpha KG, and ORN all increased glutamate concentrations at 60 min (mean: +43%, +68%, +68%, respectively, p less than 0.05 compared to basal values). However, only OKG increased proline and arginine levels at 60 min (mean: +35%, p less than 0.01 and mean: +41%, p less than 0.05). Furthermore, glutamate, proline, and arginine concentrations correlated linearly with ornithine levels at 60 min. Finally, OKG increased insulinemia and glucagonemia (mean: +24% at 15 min, p less than 0.05 and +30% at 60 min, p less than 0.01, respectively). These data provide evidence that the combination of ORN and alpha KG modifies amino acid metabolism in a way which is not observed when they are administered separately. In addition, the OKG-mediated increase in insulin levels probably does not appear to result from a direct action of ORN on pancreatic secretion.

  4. Modular pathway rewiring of Saccharomyces cerevisiae enables high-level production of L-ornithine

    DEFF Research Database (Denmark)

    Qin, Jiufu; Zhou, Yongjin J.; Krivoruchko, Anastasia

    2015-01-01

    intermediates can serve as platform cell factories for production of such products. Here we implement a modular pathway rewiring (MPR) strategy and demonstrate its use for pathway optimization resulting in high-level production of L-ornithine, an intermediate of L-arginine biosynthesis and a precursor...

  5. Weissella halotolerans W22 combines arginine deiminase and ornithine decarboxylation pathways and converts arginine to putrescine

    NARCIS (Netherlands)

    Pereira, C. I.; San Romao, M. V.; Lolkema, J. S.; Barreto Crespo, M. T.; Baretto Crespo, M.

    2009-01-01

    Aims: To demonstrate that the meat food strain Weissella halotolerans combines an ornithine decarboxylation pathway and an arginine deiminase (ADI) pathway and is able to produce putrescine, a biogenic amine. Evidence is shown that these two pathways produce a proton motive force (PMF). Methods and

  6. Diurnal changes in polyamine content, arginine and ornithine decarboxylase, and diamine oxidase in tobacco leaves

    Czech Academy of Sciences Publication Activity Database

    Gemperlová, Lenka; Nováková, Marie; Vaňková, Radomíra; Eder, Josef; Cvikrová, Milena

    2006-01-01

    Roč. 57, č. 6 (2006), s. 1413-1421 ISSN 0022-0957 R&D Projects: GA ČR GA206/03/0369 Institutional research plan: CEZ:AV0Z50380511 Keywords : Arginine decarboxylase * diamine oxidase * ornithine decarboxylase Subject RIV: ED - Physiology Impact factor: 3.630, year: 2006

  7. Ornithine: at the crossroads of multiple paths to amino acids and polyamines

    Science.gov (United States)

    Rajtilak Majumdar; Rakesh Minocha; Subhash. Minocha

    2015-01-01

    After the 20 amino acids that make up the proteins in all living organisms, ornithine perhaps occupies the most critical position among the non-protein amino acids. It sits at the crossroads of interconversions of glutamate and arginine on the one hand and the production of proline, polyamines and several alkaloids on the other: all products of tremendous importance to...

  8. Stereospecific control of peptide gas-phase ion chemistry with cis and trans cyclo ornithine residues

    Czech Academy of Sciences Publication Activity Database

    Marek, Aleš; Nguyen, H. T. H.; Brož, Břetislav; Tureček, F.

    2018-01-01

    Roč. 53, č. 2 (2018), s. 124-137 ISSN 1076-5174 Institutional support: RVO:61388963 Keywords : cis and trans isomers * cyclo ornithine * peptide dissociations * peptide ion structures * stereochemistry Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 2.422, year: 2016

  9. Randomised controlled trial of the effects of L-ornithine on stress markers and sleep quality in healthy workers.

    Science.gov (United States)

    Miyake, Mika; Kirisako, Takayoshi; Kokubo, Takeshi; Miura, Yutaka; Morishita, Koji; Okamura, Hisayoshi; Tsuda, Akira

    2014-06-03

    L-ornithine is a non-essential, non-protein amino acid. Although L-ornithine is contained in various foods, the amount is usually small.Recently, studies have shown that orally administered L-ornithine reduced the stress response in animals.From these findings, we speculated that L-ornithine may play a role in the relieve of stress and improve sleep and fatigue symptoms in humans. Through a randomised, double-blind, placebo-controlled clinical study, we asked if L-ornithine could be beneficial to stress and sleep in healthy workers. Fifty-two apparently healthy Japanese adults who had previously felt slight stress as well as fatigue were recruited to be study participants and were randomly divided into either the L-ornithine (400 mg/day) or placebo group. They orally consumed the respective test substance every day for 8 weeks. Serum was collected for the assessment of cortisol and dehydroepiandrosterone-sulphate (DHEA-S). Perceived mood and quality of sleep were measured by the Profile of Mood States (POMS), Athens Insomnia Scale (AIS), and Ogri-Shirakawa-Azumi sleep inventory MA version (OSA-MA). Serum cortisol levels and the cortisol/DHEA-S ratio were significantly decreased in the L-ornithine group in comparison with the placebo group. Also, anger was reduced and perceived sleep quality was improved in the L-ornithine group. L-ornithine supplementation has the potential to relieve stress and improve sleep quality related to fatigue, both objectively and subjectively.

  10. Recovery from inhibition by UV-irradiation of ornithine decarboxylase induction in human cells: implication of excision repair

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Hur, E.; Prager, A. (Nuclear Research Centre-Negev, Beer-Sheva (Israel)); Buonaguro, F. (Argonne National Lab., IL (USA))

    1982-05-01

    Exposure of stationary-phase human breast carcinoma (T-47D) cells to far-UV light (254nm) inhibited the appearance of induced ornithine decarboxylase (ODC) activity. The fluence response curve had a shoulder (Dsub(q)=2Jm/sup -2/) followed by an exponential decline (D/sub 0/=4.2Jm/sup -2/). The cells could recover from this inhibition when the stimulus of induction of ODC was delayed for 20-24h after irradiation. Hydroxyurea (HU) when present at 3mM during the recovery period eliminated completely the ability of the cells to recover. This effect of HU on ODC induction was partially reversed by 50..mu..M of the four deoxyribonucleosides required for DNA synthesis. Neither HU nor the deoxyribonucleosides by themselves affected ODC induction in unirradiated cells. Since HU inhibited the recovery from potentially lethal UV damage and is a known inhibitor of excision repair, it is suggested that recovery from UV-induced inhibition of ODC induction depends on excision-repair of DNA damage. This interpretation is strongly supported by the finding that specific photolysis of 5-bromodeoxyuridine, incorporated into DNA during the recovery period, inhibited recovery of ODC induction from inhibition by UV light.

  11. Local anesthetics inhibit induction of ornithine decarboxylase by the tumor promoter 12-O-tetradecanoylphorbol 13-acetate.

    OpenAIRE

    Yuspa, S H; Lichti, U; Ben, T

    1980-01-01

    The induction of ornithine decarboxylase (L-ornithine carboxy-lyase, EC 4.1.1.17) activity in mouse epidermal cells in vivo and in vitro occurs rapidly after exposure to the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA). This induction has characteristics of a cell surface receptor-mediated process. Local anesthetics modify a variety of cellular responses mediated by membrane receptors. When cultured mouse epidermal cells were exposed to the local anesthetics lidocaine, tetracaine...

  12. mu-crystallin is a mammalian homologue of Agrobacterium ornithine cyclodeaminase and is expressed in human retina.

    OpenAIRE

    Kim, R Y; Gasser, R; Wistow, G J

    1992-01-01

    mu-Crystallin is the major component of the eye lens in several Australian marsupials. The complete sequence of kangaroo mu-crystallin has now been obtained by cDNA cloning. The predicted amino acid sequence shows similarity with ornithine cyclodeaminases encoded by the tumor-inducing (Ti) plasmids of Agrobacterium tumefaciens. Until now, neither ornithine cyclodeaminase nor any structurally related enzymes have been observed in eukaryotes. RNA analysis of kangaroo tissues shows that mu-cryst...

  13. Crystallization of ornithine acetyltransferase from yeast by counter-diffusion and preliminary X-ray study

    Energy Technology Data Exchange (ETDEWEB)

    Maes, Dominique, E-mail: dominique.maes@vub.ac.be; Crabeel, Marjolaine [Laboratorium voor Ultrastructuur, Vrije Universiteit Brussel (VUB) and Vlaams Interuniversitair Instituut voor Biotechnologie (VIB), Pleinlaan 2, B-1050 Brussels (Belgium); Van de Weerdt, Cécile; Martial, Joseph [Laboratoire de Biologie Moléculaire et de Génie Génétique, Université de Liège, Allée de la Chimie 3, B-4000 Liège (Belgium); Peeters, Eveline; Charlier, Daniël [Erfelijkheidsleer en Microbiologie, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels (Belgium); Decanniere, Klaas; Vanhee, Celine; Wyns, Lode; Zegers, Ingrid [Laboratorium voor Ultrastructuur, Vrije Universiteit Brussel (VUB) and Vlaams Interuniversitair Instituut voor Biotechnologie (VIB), Pleinlaan 2, B-1050 Brussels (Belgium)

    2006-12-01

    A study on the crystallization of ornithine acetyltransferase from yeast, catalysing the fifth step in microbial arginine synthesis, is presented. The use of the counter-diffusion technique removes the disorder present in one dimension in crystals grown by either batch or hanging-drop techniques. A study is presented on the crystallization of ornithine acetyltransferase from yeast, which catalyzes the fifth step in microbial arginine synthesis. The use of the counter-diffusion technique removes the disorder present in one dimension in crystals grown by either the batch or hanging-drop techniques. This makes the difference between useless crystals and crystals that allow successful determination of the structure of the protein. The crystals belong to space group P4, with unit-cell parameters a = b = 66.98, c = 427.09 Å, and a data set was collected to 2.76 Å.

  14. Insights into the mutation-induced HHH syndrome from modeling human mitochondrial ornithine transporter-1.

    Directory of Open Access Journals (Sweden)

    Jing-Fang Wang

    Full Text Available Human mitochondrial ornithine transporter-1 is reported in coupling with the hyperornithinemia-hyperammonemia-homocitrullinuria (HHH syndrome, which is a rare autosomal recessive disorder. For in-depth understanding of the molecular mechanism of the disease, it is crucially important to acquire the 3D structure of human mitochondrial ornithine transporter-1. Since no such structure is available in the current protein structure database, we have developed it via computational approaches based on the recent NMR structure of human mitochondrial uncoupling protein (Berardi MJ, Chou JJ, et al. Nature 2011, 476:109-113. Subsequently, we docked the ligand L-ornithine into the computational structure to search for the favorable binding mode. It was observed that the binding interaction for the most favorable binding mode is featured by six remarkable hydrogen bonds between the receptor and ligand, and that the most favorable binding mode shared the same ligand-binding site with most of the homologous mitochondrial carriers from different organisms, implying that the ligand-binding sites are quite conservative in the mitochondrial carriers family although their sequences similarity is very low with 20% or so. Moreover, according to our structural analysis, the relationship between the disease-causing mutations of human mitochondrial ornithine transporter-1 and the HHH syndrome can be classified into the following three categories: (i the mutation occurs in the pseudo-repeat regions so as to change the region of the protein closer to the mitochondrial matrix; (ii the mutation is directly affecting the substrate binding pocket so as to reduce the substrate binding affinity; (iii the mutation is located in the structural region closer to the intermembrane space that can significantly break the salt bridge networks of the protein. These findings may provide useful insights for in-depth understanding of the molecular mechanism of the HHH syndrome and

  15. Expression pattern of a nuclear encoded mitochondrial arginine-ornithine translocator gene from Arabidopsis

    Directory of Open Access Journals (Sweden)

    Schneider Anja

    2003-01-01

    Full Text Available Abstract Background Arginine and citrulline serve as nitrogen storage forms, but are also involved in biosynthetic and catabolic pathways. Metabolism of arginine, citrulline and ornithine is distributed between mitochondria and cytosol. For the shuttle of intermediates between cytosol and mitochondria transporters present on the inner mitochondrial membrane are required. Yeast contains a mitochondrial translocator for ornithine and arginine, Ort1p/Arg11p. Ort1p/Arg11p is a member of the mitochondrial carrier family (MCF essential for ornithine export from mitochondria. The yeast arg11 mutant, which is deficient in Ort1p/Arg11p grows poorly on media lacking arginine. Results High-level expression of a nuclear encoded Arabidopsis thaliana homolog (AtmBAC2 of Ort1p/Arg11p was able to suppress the growth deficiency of arg11. RT-PCR analysis demonstrated expression of AtmBAC2 in all tissues with highest levels in flowers. Promoter-GUS fusions showed preferential expression in flowers, i.e. pollen, in the vasculature of siliques and in aborted seeds. Variable expression was observed in leaf vasculature. Induction of the promoter was not observed during the first two weeks in seedlings grown on media containing NH4NO3, arginine or ornithine as sole nitrogen sources. Conclusion AtmBAC2 was isolated as a mitochondrial transporter for arginine in Arabidopsis. The absence of expression in developing seeds and in cotyledons of seedlings indicates that other transporters are responsible for storage and mobilization of arginine in seeds.

  16. N-ω-chloroacetyl-l-ornithine, a new competitive inhibitor of ornithine decarboxylase, induces selective growth inhibition and cytotoxicity on human cancer cells versus normal cells.

    Science.gov (United States)

    Medina-Enríquez, Miriam Marlene; Alcántara-Farfán, Verónica; Aguilar-Faisal, Leopoldo; Trujillo-Ferrara, José Guadalupe; Rodríguez-Páez, Lorena; Vargas-Ramírez, Alba Laura

    2015-06-01

    Many cancer cells have high expression of ornithine decarboxylase (ODC) and there is a concerted effort to seek new inhibitors of this enzyme. The aim of the study was to initially characterize the inhibition properties, then to evaluate the cytotoxicity/antiproliferative cell based activity of N-ω-chloroacetyl-l-ornithine (NCAO) on three human cancer cell lines. Results showed NCAO to be a reversible competitive ODC inhibitor (Ki = 59 µM) with cytotoxic and antiproliferative effects, which were concentration- and time-dependent. The EC50,72h of NCAO was 15.8, 17.5 and 10.1 µM for HeLa, MCF-7 and HepG2 cells, respectively. NCAO at 500 µM completely inhibited growth of all cancer cells at 48 h treatment, with almost no effect on normal cells. Putrescine reversed NCAO effects on MCF-7 and HeLa cells, indicating that this antiproliferative activity is due to ODC inhibition.

  17. Tumor-promoting phorbol ester amplifies the inductions of tyrosine aminotransferase and ornithine decarboxylase by glucocorticoid

    International Nuclear Information System (INIS)

    Kido, H.; Fukusen, N.; Katunuma, N.

    1987-01-01

    In adrenalectomized rats, the tumor-promoting phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) markedly enhanced the inductions of tyrosine aminotransferase (TAT) and ornithine decarboxylase by glucocorticoids, even with sufficient concentration of glucocorticoids to have a maximal effect, whereas it had no effect on TAT activity and increased ornithine decarboxylase activity only slightly in the absence of glucocorticoids. Phorbol derivatives and components of TPA such as 4β-phorbol, phorbol 12-tetradecanoate, phorbol 13-acetate, and 4-O-methylphorbol 12-tetradecanoate 13-acetate, which have no tumor-promoting activity or ability to activate protein kinase C, did not have any effect on TAT induction by glucocorticoid. TPA enhanced the induction of TAT by various glucocorticoids but had no effect on induction of TAT by glucagon or insulin and did not enhance the induction of glucose-6-phosphate dehydrogenase by 17β-estradiol. These results suggest that TPA specifically enhances the induction of TAT and ornithine decarboxylase by glucocorticoids. Similar effects of TPA on TAT induction by glucocorticoid were observed in primary cultures of adult rat hepatocytes. Another activator of protein kinase C, rac-1,2-dioctanoylglycerol, was also found to have similar effects on the cells

  18. Profiling of ornithine lipids in bacterial extracts of Rhodobacter sphaeroides by reversed-phase liquid chromatography with electrospray ionization and multistage mass spectrometry (RPLC-ESI-MS(n)).

    Science.gov (United States)

    Granafei, Sara; Losito, Ilario; Trotta, Massimo; Italiano, Francesca; de Leo, Vincenzo; Agostiano, Angela; Palmisano, Francesco; Cataldi, Tommaso R I

    2016-01-15

    Ornithine lipids (OLs), a sub-group of the large (and of emerging interest) family of lipoamino acids of bacterial origin, contain a 3-hydroxy fatty acyl chain linked via an amide bond to the α-amino group of ornithine and via an ester bond to a second fatty acyl chain. OLs in extracts of Rhodobacter sphaeroides (R. sphaeroides) were investigated by high-performance reversed phase liquid chromatography (RPLC) with electrospray ionization mass spectrometry (ESI-MS) in negative ion mode using a linear ion trap (LIT). The presence of OLs bearing both saturated (i.e, 16:0, 17:0, 18:0, 19:0 and 20:0) and unsaturated chains (i.e., 18:1, 19:1, 19:2 and 20:1) was ascertained and their identification, even for isomeric, low abundance and partially co-eluting species, was achieved by low-energy collision induced dissociation (CID) multistage mass spectrometry (MS(n), n = 2-4). OLs signatures found in two R. sphaeroides strains, i.e., wild type 2.4.1 and mutant R26, were examined and up to 16 and 17 different OL species were successfully identified, respectively. OLs in both bacterial strains were characterized by several combinations of fatty chains on ester-linked and amide-linked 3-OH fatty acids. Multistage MS spectra of monoenoic amide-linked 3-OH acyl chains, allowed the identification of positional isomer of OL containing 18:1 (i.e. 9-octadecenoic) and 20:1 (i.e. 11-eicosenoic) fatty acids. The most abundant OL ([M-H](-) at m/z 717.5) in R. sphaeroides R26 was identified as OL 3-OH 20:1/19:1 (i.e., 3-OH-eicosenoic acid amide-linked to ornithine and esterified to a nonadecenoic chain containing a cyclopropane ring). An unusual OL (m/z 689.5 for the [M-H](-) ion), most likely containing a cyclopropene ester-linked acyl chain (i.e., OL 3-OH 18:0/19:2), was retrieved only in the carotenoidless mutant strain R26. Based on the biosynthetic pathways already known for cyclopropa(e)ne ring-including acyl chains, a plausible explanation was invoked for the enzymatic

  19. Involvement of the ornithine decarboxylase gene in acid stress response in probiotic Lactobacillus delbrueckii UFV H2b20.

    Science.gov (United States)

    Ferreira, A B; Oliveira, M N V de; Freitas, F S; Paiva, A D; Alfenas-Zerbini, P; Silva, D F da; Queiroz, M V de; Borges, A C; Moraes, C A de

    2015-01-01

    Amino acid decarboxylation is important for the maintenance of intracellular pH under acid stress. This study aims to carry out phylogenetic and expression analysis by real-time PCR of two genes that encode proteins involved in ornithine decarboxylation in Lactobacillus delbrueckii UFV H2b20 exposed to acid stress. Sequencing and phylogeny analysis of genes encoding ornithine decarboxylase and amino acid permease in L. delbrueckii UFV H2b20 showed their high sequence identity (99%) and grouping with those of L. delbrueckii subsp. bulgaricus ATCC 11842. Exposure of L. delbrueckii UFV H2b20 cells in MRS pH 3.5 for 30 and 60 min caused a significant increase in expression of the gene encoding ornithine decarboxylase (up to 8.1 times higher when compared to the control treatment). Increased expression of the ornithine decarboxylase gene demonstrates its involvement in acid stress response in L. delbrueckii UFV H2b20, evidencing that the protein encoded by that gene could be involved in intracellular pH regulation. The results obtained show ornithine decarboxylation as a possible mechanism of adaptation to an acidic environmental condition, a desirable and necessary characteristic for probiotic cultures and certainly important to the survival and persistence of the L. delbrueckii UFV H2b20 in the human gastrointestinal tract.

  20. Glutathione-supported arsenate reduction coupled to arsenolysis catalyzed by ornithine carbamoyl transferase

    International Nuclear Information System (INIS)

    Nemeti, Balazs; Gregus, Zoltan

    2009-01-01

    Three cytosolic phosphorolytic/arsenolytic enzymes, (purine nucleoside phosphorylase [PNP], glycogen phosphorylase, glyceraldehyde-3-phosphate dehydrogenase) have been shown to mediate reduction of arsenate (AsV) to the more toxic arsenite (AsIII) in a thiol-dependent manner. With unknown mechanism, hepatic mitochondria also reduce AsV. Mitochondria possess ornithine carbamoyl transferase (OCT), which catalyzes phosphorolytic or arsenolytic citrulline cleavage; therefore, we examined if mitochondrial OCT facilitated AsV reduction in presence of glutathione. Isolated rat liver mitochondria were incubated with AsV, and AsIII formed was quantified. Glutathione-supplemented permeabilized or solubilized mitochondria reduced AsV. Citrulline (substrate for OCT-catalyzed arsenolysis) increased AsV reduction. The citrulline-stimulated AsV reduction was abolished by ornithine (OCT substrate inhibiting citrulline cleavage), phosphate (OCT substrate competing with AsV), and the OCT inhibitor norvaline or PALO, indicating that AsV reduction is coupled to OCT-catalyzed arsenolysis of citrulline. Corroborating this conclusion, purified bacterial OCT mediated AsV reduction in presence of citrulline and glutathione with similar responsiveness to these agents. In contrast, AsIII formation by intact mitochondria was unaffected by PALO and slightly stimulated by citrulline, ornithine, and norvaline, suggesting minimal role for OCT in AsV reduction in intact mitochondria. In addition to OCT, mitochondrial PNP can also mediate AsIII formation; however, its role in AsV reduction appears severely limited by purine nucleoside supply. Collectively, mitochondrial and bacterial OCT promote glutathione-dependent AsV reduction with coupled arsenolysis of citrulline, supporting the hypothesis that AsV reduction is mediated by phosphorolytic/arsenolytic enzymes. Nevertheless, because citrulline cleavage is disfavored physiologically, OCT may have little role in AsV reduction in vivo.

  1. Renal ornithine decarboxylase activity, polyamines, and compensatory renal hypertrophy in the rat

    International Nuclear Information System (INIS)

    Humphreys, M.H.; Etheredge, S.B.; Lin, Shanyan; Ribstein, J.; Marton, L.J.

    1988-01-01

    The authors determined the role of ornithine decarboxylase (ODC) in compensatory renal hypertrophy (CRH) by relating renal ODC activity and polyamine content to kidney size, expressed as a percent of body weight, 1 wk after unilateral nephrectomy (UN). In normal rats, renal ODC activity increased after UN; 1 wk later the remaining kidney weight had increased. Renal concentration of putrescine, the product of ODC's decarboxylation of ornithine, was increased 3, 8, and 48 h after UN, but concentrations of polyamines synthesized later in the pathway, spermidine and spermine, were not appreciably affected. Pretreatment with difluoromethylornithine (DFMO), an irreversible inhibitor of ODC inhibited both base-line renal ODC activity and putrescine concentration as well as increases stimulated by UN, although concentrations of spermidine and spermine were not decreased. In hypophysectomized rats, both increased renal ODC activity and CRH occurred as well, indicating that these two consequences of UN do not require intact pituitary function. Thus stimulation of renal ODC activity and putrescine content do not appear critical to the process of CRH after UN

  2. Influence of ornithine decarboxylase antizymes and antizyme inhibitors on agmatine uptake by mammalian cells.

    Science.gov (United States)

    Ramos-Molina, Bruno; López-Contreras, Andrés J; Lambertos, Ana; Dardonville, Christophe; Cremades, Asunción; Peñafiel, Rafael

    2015-05-01

    Agmatine (4-aminobutylguanidine), a dicationic molecule at physiological pH, exerts relevant modulatory actions at many different molecular target sites in mammalian cells, having been suggested that the administration of this compound may have therapeutic interest. Several plasma membrane transporters have been implicated in agmatine uptake by mammalian cells. Here we report that in kidney-derived COS-7 cell line, at physiological agmatine levels, the general polyamine transporter participates in the plasma membrane translocation of agmatine, with an apparent Km of 44 ± 7 µM and Vmax of 17.3 ± 3.3 nmol h(-1) mg(-1) protein, but that at elevated concentrations, agmatine can be also taken up by other transport systems. In the first case, the physiological polyamines (putrescine, spermidine and spermine), several diguanidines and bis(2-aminoimidazolines) and the polyamine transport inhibitor AMXT-1501 markedly decreased agmatine uptake. In cells transfected with any of the three ornithine decarboxylase antizymes (AZ1, AZ2 and AZ3), agmatine uptake was dramatically reduced. On the contrary, transfection with antizyme inhibitors (AZIN1 and AZIN2) markedly increased the transport of agmatine. Furthermore, whereas putrescine uptake was significantly decreased in cells transfected with ornithine decarboxylase (ODC), the accumulation of agmatine was stimulated, suggesting a trans-activating effect of intracellular putrescine on agmatine uptake. All these results indicate that ODC and its regulatory proteins (antizymes and antizyme inhibitors) may influence agmatine homeostasis in mammalian tissues.

  3. The arginine-ornithine antiporter ArcD contributes to biological fitness of Streptococcus suis

    Directory of Open Access Journals (Sweden)

    Marcus eFulde

    2014-08-01

    Full Text Available The arginine-ornithine antiporter (ArcD is part of the Arginine Deiminase System (ADS, a catabolic, energy-providing pathway found in a variety of different bacterial species, including the porcine zoonotic pathogen Streptococcus suis. The ADS has recently been shown to play a role in the pathogenicity of S. suis, in particular in its survival in host cells. The contribution of arginine and arginine transport mediated by ArcD, however, has yet to be clarified. In the present study, we showed by experiments using [U-13C6]arginine as a tracer molecule that S. suis is auxotrophic for arginine and that bacterial growth depends on the uptake of extracellular arginine. To further study the role of ArcD in arginine metabolism, we generated an arcD-specific mutant strain and characterized its growth compared to the wild-type (WT strain, a virulent serotype 2 strain. The mutant strain showed a markedly reduced growth rate in chemically defined media supplemented with arginine when compared to the WT strain, indicating that ArcD promotes arginine uptake. To further evaluate the in vivo relevance of ArcD, we studied the intracellular bacterial survival of the arcD mutant strain in an epithelial cell culture infection model. The mutant strain was substantially attenuated, and its reduced intracellular survival rate correlated with a lower ability to neutralize the acidified environment. Based on these results, we propose that ArcD, by its function as an arginine-ornithine antiporter, is important for supplying arginine as substrate of the ADS and, thereby, contributes to biological fitness and virulence of S. suis in the host.

  4. Effects of bis(guanylhydrazones) on the activity and expression of ornithine decarboxylase.

    Science.gov (United States)

    Nikula, P; Alhonen-Hongisto, L; Jänne, J

    1985-01-01

    Derivatives of glyoxal bis(guanylhydrazone) (GBG), such as methylglyoxal bis(guanylhydrazone) and ethylglyoxal bis(guanylhydrazone), are potent inhibitors of S-adenosylmethionine decarboxylase (EC 4.1.1.50), the key enzyme required for the synthesis of spermidine and spermine. These compounds, but not the parent compound, induce a massive accumulation of putrescine, partly by blocking the conversion of putrescine into spermidine, but also by strikingly stimulating ornithine decarboxylase (ODC; EC 4.1.1.17) activity. The mechanism of the stimulation of ODC activity and enhanced accumulation of the enzyme protein apparently involved a distinct stabilization of the enzyme against intracellular degradation. However, although the parent compound GBG also stabilized ODC, it powerfully inhibited the enzyme activity and the accumulation of immunoreactive protein in cultured L1210 leukaemia cells. Kinetic considerations indicated that, in addition to the stabilization, all three compounds, GBG in particular, inhibited the expression of ODC. It is unlikely that the decreased rate of synthesis of ODC was attributable to almost unaltered amounts of mRNA in drug-treated cells, thus supporting the view that especially GBG apparently depressed the expression of ODC at some post-transcriptional level. Images PMID:4062886

  5. Polyamine regulation of ornithine decarboxylase and its antizyme in intestinal epithelial cells.

    Science.gov (United States)

    Yuan, Q; Ray, R M; Viar, M J; Johnson, L R

    2001-01-01

    Ornithine decarboxylase (ODC) is feedback regulated by polyamines. ODC antizyme mediates this process by forming a complex with ODC and enhancing its degradation. It has been reported that polyamines induce ODC antizyme and inhibit ODC activity. Since exogenous polyamines can be converted to each other after they are taken up into cells, we used an inhibitor of S-adenosylmethionine decarboxylase, diethylglyoxal bis(guanylhydrazone) (DEGBG), to block the synthesis of spermidine and spermine from putrescine and investigated the specific roles of individual polyamines in the regulation of ODC in intestinal epithelial crypt (IEC-6) cells. We found that putrescine, spermidine, and spermine inhibited ODC activity stimulated by serum to 85, 46, and 0% of control, respectively, in the presence of DEGBG. ODC activity increased in DEGBG-treated cells, despite high intracellular putrescine levels. Although exogenous spermidine and spermine reduced ODC activity of DEGBG-treated cells close to control levels, spermine was more effective than spermidine. Exogenous putrescine was much less effective in inducing antizyme than spermidine or spermine. High putrescine levels in DEGBG-treated cells did not induce ODC antizyme when intracellular spermidine and spermine levels were low. The decay of ODC activity and reduction of ODC protein levels were not accompanied by induction of antizyme in the presence of DEGBG. Our results indicate that spermine is the most, and putrescine the least, effective polyamine in regulating ODC activity, and upregulation of antizyme is not required for the degradation of ODC protein.

  6. Insights on ornithine decarboxylase silencing as a potential strategy for targeting retinoblastoma.

    Science.gov (United States)

    Muthukumaran, Sivashanmugam; Bhuvanasundar, Renganathan; Umashankar, Vetrivel; Sulochana, K N

    2018-02-01

    Ornithine Decarboxylase (ODC) is a key enzyme involved in polyamine synthesis and is reported to be up regulated in several cancers. However, the effect of ODC gene silencing in retinoblastoma is to be understood for utilization in therapeutic applications. Hence, in this study, a novel siRNA (small interference RNA) targeting ODC was designed and validated in Human Y79 retinoblastoma cells for its effects on intracellular polyamine levels, Matrix Metalloproteinase 2 & 9 activity and Cell cycle. The designed siRNA showed efficient silencing of ODC mRNA expression and protein levels in Y79 cells. It also showed significant reduction of intracellular polyamine levels and altered levels of oncogenic LIN28b expression. By this study, a regulatory loop is proposed, wherein, ODC silencing in Y79 cells to result in decreased polyamine levels, thereby, leading to altered protein levels of Lin28b, MMP-2 and MMP-9, which falls in line with earlier studies in neuroblastoma. Thus, by this study, we propose ODC silencing as a prospective strategy for targeting retinoblastoma. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  7. Improved Intranasal Retentivity and Transnasal Absorption Enhancement by PEGylated Poly-l-ornithine

    Directory of Open Access Journals (Sweden)

    Yusuke Kamiya

    2018-01-01

    Full Text Available We reported that the introduction of polyethylene glycol (PEG to poly-l-ornithine (PLO, which is an homopolymeric basic amino acid having absorption-enhancement ability, prolonged retention time in an in vitro inclined plate test, probably due to an increase in viscosity caused by PEGylation. The aim of the present study is to investigate whether the introduction of PEG chains to PLO improves intranasal retention and transnasal absorption in vivo. We performed intranasal administration experiments using PLO and PEG-PLO with a model drug, fluorescein isothiocyanate dextran (FD-4, in rats under closed and open systems. In the open system, transition of plasma FD-4 concentration after co-administration with unmodified PLO was low, and the area under the plasma concentration-time curve (AUC decreased to about 60% of that in the closed system. In contrast, the AUC after co-administration with PEG-PLO in the open system was about 90% of that in the closed system, and the transition of plasma FD-4 concentration and FD-4 absorption profile were similar to those of the closed system. These findings indicate that introducing PEG chains to homopolymeric basic amino acids (HPBAAs is a very useful method for developing a functional absorption enhancer that can exhibit an efficient in vivo absorption-enhancing effect.

  8. Molecular basis of ornithine aminotransferase deficiency in B-6-responsive and -nonresponsive forms of gyrate atrophy

    International Nuclear Information System (INIS)

    Ramesh, V.; McClatchey, A.I.; Ramesh, N.; Benoit, L.A.; Berson, E.L.; Shih, V.E.; Gusella, J.F.

    1988-01-01

    Gyrate atrophy (GA), a recessive eye disease involving progressive loss of vision due to chorioretinal degeneration, is associated with a deficiency of the mitochondrial enzyme ornithine aminotransferase with consequent hyperornithinemia. Genetic heterogeneity of GA has been suggested by the demonstration that administration of pyridoxine to increase the level of pyridoxal phosphate, a cofactor of OATase, reduces hyperornithinemia in a subset of patients. The authors have cloned and sequences cDNAs for OATase from two GA patients, one responsive and one nonresponsive to pyridoxine treatment. The respective cDNAs contained different single missense mutations, which were sufficient to eliminate OATase activity when each cDNA was tested in a eukaryotic expression system. However, like the enzyme in fibroblasts from the pyridoxine-responsive patient, OATase encoded by the corresponding cDNA from this individual showed a significant increase in activity when assayed in the presence of an increased pyridoxal phosphate concentration. These data firmly establish that both pyridoxine responsive and nonresponsive forms of GA result from mutations in the OATase structural gene. Moreover, they provide a molecular characterization of the primary lesion in a pyridoxine-responsive genetic disorder

  9. Ornithine decarboxylase and extracellular polyamines regulate microvascular sprouting and actin cytoskeleton dynamics in endothelial cells

    International Nuclear Information System (INIS)

    Kucharzewska, Paulina; Welch, Johanna E.; Svensson, Katrin J.; Belting, Mattias

    2010-01-01

    The polyamines are essential for cancer cell proliferation during tumorigenesis. Targeted inhibition of ornithine decarboxylase (ODC), i.e. a key enzyme of polyamine biosynthesis, by α-difluoromethylornithine (DFMO) has shown anti-neoplastic activity in various experimental models. This activity has mainly been attributed to the anti-proliferative effect of DFMO in cancer cells. Here, we provide evidence that unperturbed ODC activity is a requirement for proper microvessel sprouting ex vivo as well as the migration of primary human endothelial cells. DFMO-mediated ODC inhibition was reversed by extracellular polyamine supplementation, showing that anti-angiogenic effects of DFMO were specifically related to polyamine levels. ODC inhibition was associated with an abnormal morphology of the actin cytoskeleton during cell spreading and migration. Moreover, our data suggest that de-regulated actin cytoskeleton dynamics in DFMO treated endothelial cells may be related to constitutive activation of the small GTPase CDC42, i.e. a well-known regulator of cell motility and actin cytoskeleton remodeling. These insights into the potential role of polyamines in angiogenesis should stimulate further studies testing the combined anti-tumor effect of polyamine inhibition and established anti-angiogenic therapies in vivo.

  10. Ornithine decarboxylase regulates the activity and localization of rhoA via polyamination

    International Nuclear Information System (INIS)

    Maekitie, Laura T.; Kanerva, Kristiina; Andersson, Leif C.

    2009-01-01

    Ornithine decarboxylase (ODC) is the rate-limiting enzyme of polyamine synthesis. Polyamines and ODC are connected to cell proliferation and transformation. Resting cells display a low ODC activity while normal, proliferating cells display fluctuations in ODC activity that coincide with changes in the actin cytoskeleton during the cell cycle. Cancerous cells display constitutively elevated ODC activity. Overexpression of ODC in NIH 3T3 fibroblasts induces a transformed phenotype. The cytoskeletal rearrangements during cytokinesis and cell transformation are intimately coupled to the ODC activity but the molecular mechanisms have remained elusive. In this study we investigated how ODC and polyamines influence the organization of the cytoskeleton. Given that the small G-proteins of the rho family are key modulators of the actin cytoskeleton, we investigated the molecular interactions of rhoA with ODC and polyamines. Our results show that transglutaminase-catalyzed polyamination of rhoA regulates its activity. The polyamination status of rhoA crucially influences the progress of the cell cycle as well as the rate of transformation of rat fibroblasts infected with temperature-sensitive v-src. We also show that ODC influences the intracellular distribution of rhoA. These findings provide novel insights into the mechanisms by which ODC and polyamines regulate the dynamics of the cytoskeleton during cell proliferation and transformation

  11. Adaptative increase of ornithine production and decrease of ammonia metabolism in rat colonocytes after hyperproteic diet ingestion.

    Science.gov (United States)

    Mouillé, Béatrice; Robert, Véronique; Blachier, François

    2004-08-01

    Chronic high-protein consumption leads to increased concentrations of NH(4)(+)/NH(3) in the colon lumen. We asked whether this increase has consequences on colonic epithelial cell metabolism. Rats were fed isocaloric diets containing 20 (P20) or 58% (P58) casein as the protein source for 7 days. NH(4)(+)/NH(3) concentration in the colonic lumen and in the colonic vein blood as well as ammonia metabolism by isolated surface colonic epithelial cells was determined. After 2 days of consumption of the P58 diet, marked increases of luminal and colonic vein blood NH(4)(+)/NH(3) concentrations were recorded when compared with the values obtained in the P20 group. Colonocytes recovered from the P58 group were characterized at that time and thereafter by an increased capacity for l-ornithine and urea production through arginase (P diet consumption, however, the ammonia metabolism into l-citrulline was found lower (P < 0.01) when compared with the values measured in the colonocytes recovered from the P20 group despite any decrease in the related enzymatic activities (i.e., carbamoyl-phosphate synthetase I and ornithine carbamoyl transferase). This decrease was found to coincide with a return of blood NH(4)(+)/NH(3) concentration in colonic portal blood to values close to the one recorded in the P20 group. In response to increased NH(4)(+)/NH(3) concentration in the colon, the increased capacity of the colonocytes to synthesize l-ornithine is likely to correspond to an elevated l-ornithine requirement for the elimination of excessive blood ammonia in the liver urea cycle. Moreover, in the presence of NH(4)Cl, colonocytes diminished their synthesis capacity of l-citrulline from l-ornithine, allowing a lower cellular utilization of this latter amino acid. These results are discussed in relationship with an adaptative process that would be related to both interorgan metabolism and to the role of the colonic epithelium as a first line of defense toward luminal NH(4)(+)/NH(3

  12. Expression and Bioinformatic Analysis of Ornithine Aminotransferase 
in Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Danfei ZHOU

    2012-09-01

    Full Text Available Background and objective It has been proven that ornithine aminotransferase (OAT might play an important role in the oncogenesis and progression of numerous malignant tumors. The aim of this study is to detect the mRNA and protein expression of OAT in non-small cell lung cancer (NSCLC, as well as to analyze the bioinformatic features and binary interactions. Methods OAT mRNA expression was detected in A549 and 16HBE cell lines by reverse transcription-polymerase chain reaction. OAT protein expression was determined in 55 cases of NSCLC and 17 cases of adjacent non-tumor lung tissues by immunohistochemical staining. The bioinformatic features and binary interactions of OAT were analyzed. Gene ontology annotation and signal pathway analysis were performed. Results OAT mRNA expression in A549 cells was 2.85-fold lower than that in 16HBE cells. OAT protein expression was significantly higher in NSCLC tissues than that in adjacent non-tumor lung tissues. A significant difference of OAT protein expression was existed between squamous cell lung cancer and adenocarcinoma (P<0.05, but was not correlated with the gender, age, lymph node metastasis, tumor size, and TNM stages. Bioinformatic analysis suggested that OAT was a highly homologous and stable protein located in the mitochondria. An aminotran-3 domain and several sites of phosphorylation, which may function in signal transduction, gene transcription, and molecular transit, were found. In the 54 selected binary interactions of OAT, TNF and TRAF6 play roles in the NF-κB pathway. Conclusion OAT may play an important role in the oncogenesis and progression of NSCLC. Thus, OAT may be a novel biomarker for the diagnosis of NSCLC or a new target for its treatment.

  13. Ornithine decarboxylase activity in rat organs and tissues under artificial hypobiosis.

    Science.gov (United States)

    Aksyonova, G E; Logvinovich, O S; Fialkovskaya, L A; Afanasyev, V N; Ignat'ev, D A; Kolomiytseva, I K

    2010-09-01

    The influence of hypothermia-hypoxia-hypercapnia on ornithine decarboxylase (ODC, EC 4.1.1.17) activities in rat organs and tissues and also on the thymocyte distribution throughout the cell cycle stages was studied. The state of artificial hypobiosis in rats on decrease in the body temperature to 14.4-18.0°C during 3.0-3.5 h was accompanied by drops in the ODC activities in the neocortex and liver by 50-60% and in rapidly proliferating tissues (thymus, spleen, and small intestine mucosa) by 80% of the control value. In kidneys the ODC activity raised to 200% of the control level. Twenty-four hours after termination of the cooling and replacing the rats under the standard conditions, the ODC activities in the neocortex, liver, kidneys, spleen, and intestinal mucosa returned to the control values, but remained decreased in the thymus. Forty-eight hours later the ODC activities in the thymus and spleen exceeded the normal level. The distribution of thymocytes throughout the cell cycle stages did not change in rats in the state of hypothermia (hypobiosis); 24 and 48 h after termination of the cooling the fraction of thymocytes in the S stage was decreased and the fraction of the cells in the G(0)+G(1) stage was increased. The normal distribution of thymocytes throughout the cell cycle stages recovered in 72 h. Thus, in the thymus the diminution of the ODC activity preceded the suppression of the cell proliferation rate. The tissue-specific changes in the ODC activity are suggested to reflect adaptive changes in the functional and proliferative activities of organs and tissues during the development of hypobiosis under conditions of hypothermia-hypoxia-hypercapnia.

  14. [Ornithine decarboxylase in mammalian organs and tissues at hibernation and artificial hypobiosis].

    Science.gov (United States)

    Logvinovich, O S; Aksenova, G E

    2013-01-01

    Ornithine decarboxylase (ODC, EC 4.1.1.17.) is a short-lived and dynamically regulated enzyme of polyamines biosynthesis. Regulation of functional, metabolic and proliferative state of organs and tissues involves the modifications of the ODC enzymatic activity. The organ-specific changes in ODC activity were revealed in organs and tissues (liver, spleen, bone marrow, kidney, and intestinal mucosa) of hibernating mammals - squirrels Spermophilus undulates - during the hibernating season. At that, a positive correlation was detected between the decline and recovery of the specialized functions of organs and tissues and the respective modifications of ODC activity during hibernation bouts. Investigation of changes in ODC activity in organs and tissues of non-hibernating mammals under artificial hypobiosis showed that in Wistar rats immediately after exposure to hypothermia-hypoxia-hypercapnia (hypobiosis) the level of ODC activity was low in thymus, spleen, small intestine mucosa, neocortex, and liver. The most marked reduction in enzyme activity was observed in actively proliferating tissues: thymus, spleen, small intestine mucosa. In bone marrow of squirrels, while in a state of torpor, as well as in thymus of rats after exposure to hypothermia-hypoxia-hypercapnia, changes in the ODC activity correlated with changes in the rate of cell proliferation (by the criterion of cells distribution over cell cycle). The results obtained, along with the critical analysis of published data, indicate that the ODC enzyme is involved in biochemical adaptation of mammals to natural and artificial hypobiosis. A decline in the ODC enzymatic activity indicates a decline in proliferative, functional, and metabolic activity of organs and tissues of mammals (bone marrow, mucosa of small intestine, thymus, spleen, neocortex, liver, kidneys) when entering the state of hypobiosis.

  15. Gamma radiation inhibits the appearance of induced ornithine decarboxylase activity in Chinese hamster cells

    International Nuclear Information System (INIS)

    Ben-Hur, E.; Heimer, Y.M.; Riklis, E.

    1981-01-01

    Ornithine decarboxylase activity of Chinese hamster cells (ODC, EC 4.1.1.17) can be induced in plateau phase by change of medium. Exposure of the cells to gamma radiation before induction reduces the amount of ODC activity induced. The dose-response curve is exponential with a D 0 of 106 krad. Exposure of BUdR-substituted cells is more effective in reducing ODC induction at high doses, with a D 0 of 38 krad. Cells can recover from the reduction incurred by 74 krad if enzyme induction is delayed for 2 hours after exposure. Treatment of the cells with psoralen-plus-light completely inhibits RNA synthesis without affecting protein synthesis (Heimer, Ben-Hur and Riklis 1977, 1978). Using this procedure it is shown that the effect of gamma radiation on inducible ODC activity is due not only to DNA damage but also involves a post-transcriptional effect. This conclusion is supported by employing a heat shock to inhibit protein synthesis prior to gamma-irradiation of log-phase cells. In such cells the increased activity of ODC upon transfer to 37 0 C is due primarily to enzyme synthesis using pre-existing RNA species during the first few hours. A low concentration of actinomycin D, which inhibits rRNA synthesis, applied during the recovery period, prevents the recovery of the cells' capacity for maximal ODC induction. This may indicate that, in order to recover, the cells have to repair damage to the ribosomes as well as to DNA. (author)

  16. Spermidine mediates degradation of ornithine decarboxylase by a non-lysosomal, ubiquitin-independent mechanism

    International Nuclear Information System (INIS)

    Glass, J.R.; Gerner, E.W.

    1987-01-01

    The mechanism of spermidine-induced ornithine decarboxylase (OCD, E.C. 4.1.1.17) inactivation was investigated using Chinese hamster ovary (CHO) cells, maintained in serum-free medium, which display a stabilization of ODC owing to the lack of accumulation of putrescine and spermidine. Treatment of cells with 10 μM exogenous spermidine leads to rapid decay of ODC activity accompanied by a parallel decrease in enzyme protein. Analysis of the decay of [ 35 S]methionine-labeled ODC and separation by two-dimensional electrophoresis revealed no detectable modification in ODC structure during enhanced degradation. Spermidine-mediated inactivation of ODC occurred in a temperature-dependent manner exhibiting pseudo-first-order kinetics over a temperature range of 22-37 0 C. In cultures treated continuously, an initial lag was observed after treatment with spermidine, followed by a rapid decline in activity as an apparent critical concentration of intracellular spermidine was achieved. Treating cells at 22 0 C for 3 hours with 10 μ M spermidine, followed by removal of exogenous polyamine, and then shifting to varying temperatures, resulted in rates of ODC inactivation identical with that determined with a continuous treatment. Arrhenius analysis showed that polyamine mediated inactivation of ODC occurred with an activation energy of approximately 16 kcal/mol. Treatment of cells with lysosomotrophic agents had no effect of ODC degradation. ODC turnover was not dependent on ubiquitin-dependent proteolysis. These data support the hypothesis that spermidine regulates ODC degradation via a mechanism requiring new protein synthesis, and that this occurs via a non-lysosomal, ubiquitin-independent pathway

  17. Construction of a highly efficient Bacillus subtilis 168 whole-cell biocatalyst and its application in the production of L-ornithine.

    Science.gov (United States)

    Wang, Meizhou; Xu, Meijuan; Rao, Zhiming; Yang, Taowei; Zhang, Xian

    2015-11-01

    L-Ornithine, a non-protein amino acid, is usually extracted from hydrolyzed protein as well as produced by microbial fermentation. Here, we focus on a highly efficient whole-cell biocatalyst for the production of L-ornithine. The gene argI, encoding arginase, which catalyzes the hydrolysis of L-arginine to L-ornithine and urea, was cloned from Bacillus amyloliquefaciens B10-127 and expressed in GRAS strain Bacillus subtilis 168. The recombinant strain exhibited an arginase activity of 21.9 U/mg, which is 26.7 times that of wild B. subtilis 168. The optimal pH and temperature of the purified recombinant arginase were 10.0 and 40 °C, respectively. In addition, the recombinant arginase exhibited a strong Mn(2+) preference. When using whole-cell biocatalyst-based bioconversion, a hyper L-ornithine production of 356.9 g/L was achieved with a fed-batch strategy in a 5-L reactor within 12 h. This whole-cell bioconversion study demonstrates an environmentally friendly strategy for L-ornithine production in industry.

  18. Effect of short-term ornithine alpha-ketoglutarate pretreatment on intestinal ischemia-reperfusion in rats

    OpenAIRE

    Gonçalves,Eduardo Silvio Gouveia; Rabelo,Camila Menezes; Prado Neto,Alberico Ximenes do; Garcia,José Huygens Parente; Guimarães,Sérgio Botelho; Vasconcelos,Paulo Roberto Leitão de

    2011-01-01

    PURPOSE: To investigate the effects of preventive enteral administration of ornithine alpha-ketoglutarate (OKG) in an ischemia-reperfusion rat model. METHODS: Sixty rats were randomized into five groups (G1-G5, n = 12). Each group was divided into two subgroups (n = 6) and treated with calcium carbonate (CaCa) or OKG by gavage. Thirty minutes later, the animals were anesthetized with xylazine 15mg + ketamine 1mg ip and subjected to laparotomy. G1-G3 rats served as controls. Rats in groups G4 ...

  19. Partial Cancellation

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Partial Cancellation. Full Cancellation is desirable. But complexity requirements are enormous. 4000 tones, 100 Users billions of flops !!! Main Idea: Challenge: To determine which cross-talker to cancel on what “tone” for a given victim. Constraint: Total complexity is ...

  20. [Hyperammonemia type II as an example of urea cycle disorder].

    Science.gov (United States)

    Hawrot-Kawecka, Anna M; Kawecki, Grzegorz P; Duława, Jan

    2006-01-01

    Ornithine transcarbamylase deficiency is the most common inherited urea cycle disorder. Its clinical manifestations as lethargy, vomites, coma and cerebral edema are the effect of the higher concentration of the ammonia in plasma. Hyperammonemia, caused by mutation in ornithine transcarbamylase gene, is often considered as a reason of coma by pediatricians but skipped by internist, although it is the third reason of hepatic coma in adults. This article is the recapitulation of published studies and their implication on everyday clinical practice.

  1. Partial processing

    International Nuclear Information System (INIS)

    1978-11-01

    This discussion paper considers the possibility of applying to the recycle of plutonium in thermal reactors a particular method of partial processing based on the PUREX process but named CIVEX to emphasise the differences. The CIVEX process is based primarily on the retention of short-lived fission products. The paper suggests: (1) the recycle of fission products with uranium and plutonium in thermal reactor fuel would be technically feasible; (2) it would, however, take ten years or more to develop the CIVEX process to the point where it could be launched on a commercial scale; (3) since the majority of spent fuel to be reprocessed this century will have been in storage for ten years or more, the recycling of short-lived fission products with the U-Pu would not provide an effective means of making refabrication fuel ''inaccessible'' because the radioactivity associated with the fission products would have decayed. There would therefore be no advantage in partial processing

  2. Partial gigantism

    Directory of Open Access Journals (Sweden)

    М.М. Karimova

    2017-05-01

    Full Text Available A girl with partial gigantism (the increased I and II fingers of the left foot is being examined. This condition is a rare and unresolved problem, as the definite reason of its development is not determined. Wait-and-see strategy is recommended, as well as correcting operations after closing of growth zones, and forming of data pool for generalization and development of schemes of drug and radial therapeutic methods.

  3. Effect of ethanol and low pH on citrulline and ornithine excretion and arc gene expression by strains of Lactobacillus brevis and Pediococcus pentosaceus.

    Science.gov (United States)

    Araque, Isabel; Bordons, Albert; Reguant, Cristina

    2013-02-01

    The accumulation of citrulline and ornithine in wine or beer as a result of the arginine catabolism of some lactic acid bacteria (LAB) species increases the risk of ethyl carbamate and putrescine formation, respectively. Several LAB species, which are found as spoilage bacteria in alcoholic beverages, have been reported to be arginine degrading. This study evaluates the effect of ethanol content and low pH on the excretion of citrulline and ornithine by two strains belonging to the potential contaminant species Lactobacillus brevis and Pediococcus pentosaceus. In the conditions that most affected cell viability, arginine consumption per cell increased noticeably, indicating that arginine utilization may be a stress responsive mechanism. L. brevis showed a higher accumulation of ornithine in the media than P. pentosaceus. In the presence of ethanol, a higher expression of the arcC gene was found in P. pentosaceus, which resulted in a lower excretion of citrulline and ornithine than in L. brevis. This suggests that L. brevis is more likely to produce these amino acids, which are precursors of ethyl carbamate and putrescine. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Biochemical and ultrastructural changes in rabbit sclera after treatment with 7-methylxanthine, theobromine, acetazolamide, or L-ornithine

    Science.gov (United States)

    Trier, K.; Olsen, E. B.; Kobayashi, T.; Ribel-Madsen, S. M.

    1999-01-01

    AIMS—To examine a possible effect of 7-methylxanthine, theobromine, acetazolamide, or L-ornithine on the ultrastructure and biochemical composition of rabbit sclera.
METHODS—Groups of pigmented rabbits, six in each group, were dosed during 10 weeks with one of the substances under investigation, and one untreated group was the control. Samples of anterior and posterior sclera were taken for determination of hydroxyproline, hydroxylysine, proline, proteoglycans, uronic acids and dermatan sulphate, chondroitin sulphate, and hyaluronic acid. Sections were examined with electron microscopy, and the diameter of the individual collagen fibrils was measured.
RESULTS—Treatment with theobromine produced a significant increase in the contents of hydroxylysine, hydroxyproline, and proline in both anterior and posterior sclera, while 7-methylxanthine increased the contents of hydroxyproline and proline selectively in posterior sclera. Acetazolamide, on the other hand, significantly decreased the contents of hydroxyproline and proline in samples from anterior sclera. Uronic acids in both anterior and posterior sclera were significantly reduced by treatment with 7-methylxanthine, and L-ornithine significantly reduced uronic acids in posterior sclera. An inverse correlation between contents of hydroxyproline and uronic acids was found. The mean diameter of collagen fibrils was significantly higher in the posterior sclera from rabbits treated with 7-methylxanthine or theobromine, and significantly lower in rabbits treated with acetazolamide or L-ornithine compared with controls. In the anterior sclera, fibril diameter was significantly reduced in all treatment groups compared with controls. A positive, significant correlation between fibril diameter and content of hydroxyproline and proline was found in posterior sclera.
CONCLUSION—7-Methylxanthine, a metabolite of caffeine, increases collagen concentration and the diameter of collagen fibrils in the posterior

  5. Differential retinoic acid inhibition of ornithine decarboxylase induction by 12-O-tetradecanoylphorbol-13-acetate and by germicidal ultraviolet light

    International Nuclear Information System (INIS)

    Lichti, U.; Patterson, E.; Hennings, H.; Yuspa, S.H.

    1981-01-01

    Several retinoids including retinoic acid effectively inhibit phorbol ester-mediated tumor promotion and ornithine decarboxylase (ODC) induction in mouse epidermis. To understand better the possible cellular site of action of retinoids, the inhibitory action of retinoic acid on the induction of ODC was compared for two distinctly different inducers, namely, 12-O-tetradecanoylphorbol-13-acetate (TPA) and germicidal ultraviolet light (uv), in primary mouse epidermal cell cultures. It was found that the induction of ODC by TPA is almost completely prevented by retinoic acid while the induction by uv is only moderately inhibited. The differential inhibition of enzyme induction cannot be accounted for by selective retinoid inhibition of DNA, RNA, or protein synthesis either alone or in concert with TPA or uv. These agents possibly act at transcription or translation, both of which are required for ODC induction by TPA or uv

  6. The Aspergillus fumigatus siderophore biosynthetic gene sidA, encoding L-ornithine N5-oxygenase, is required for virulence.

    Science.gov (United States)

    Hissen, Anna H T; Wan, Adrian N C; Warwas, Mark L; Pinto, Linda J; Moore, Margo M

    2005-09-01

    Aspergillus fumigatus is the leading cause of invasive mold infection and is a serious problem in immunocompromised populations worldwide. We have previously shown that survival of A. fumigatus in serum may be related to secretion of siderophores. In this study, we identified and characterized the sidA gene of A. fumigatus, which encodes l-ornithine N(5)-oxygenase, the first committed step in hydroxamate siderophore biosynthesis. A. fumigatus sidA codes for a protein of 501 amino acids with significant homology to other fungal l-ornithine N(5)-oxygenases. A stable DeltasidA strain was created by deletion of A. fumigatus sidA. This strain was unable to synthesize the siderophores N',N",N'''-triacetylfusarinine C (TAF) and ferricrocin. Growth of the DeltasidA strain was the same as that of the wild type in rich media; however, the DeltasidA strain was unable to grow in low-iron defined media or media containing 10% human serum unless supplemented with TAF or ferricrocin. No significant differences in ferric reduction activities were observed between the parental strain and the DeltasidA strain, indicating that blocking siderophore secretion did not result in upregulation of this pathway. Unlike the parental strain, the DeltasidA strain was unable to remove iron from human transferrin. A rescued strain (DeltasidA + sidA) was constructed; it produced siderophores and had the same growth as the wild type on iron-limited media. Unlike the wild-type and rescued strains, the DeltasidA strain was avirulent in a mouse model of invasive aspergillosis, indicating that sidA is necessary for A. fumigatus virulence.

  7. Arg279 is the key regulator of coenzyme selectivity in the flavin-dependent ornithine monooxygenase SidA.

    Science.gov (United States)

    Robinson, Reeder; Franceschini, Stefano; Fedkenheuer, Michael; Rodriguez, Pedro J; Ellerbrock, Jacob; Romero, Elvira; Echandi, Maria Paulina; Martin Del Campo, Julia S; Sobrado, Pablo

    2014-04-01

    Siderophore A (SidA) is a flavin-dependent monooxygenase that catalyzes the NAD(P)H- and oxygen-dependent hydroxylation of ornithine in the biosynthesis of siderophores in Aspergillus fumigatus and is essential for virulence. SidA can utilize both NADPH or NADH for activity; however, the enzyme is selective for NADPH. Structural analysis shows that R279 interacts with the 2'-phosphate of NADPH. To probe the role of electrostatic interactions in coenzyme selectivity, R279 was mutated to both an alanine and a glutamate. The mutant proteins were active but highly uncoupled, oxidizing NADPH and producing hydrogen peroxide instead of hydroxylated ornithine. For wtSidA, the catalytic efficiency was 6-fold higher with NADPH as compared to NADH. For the R279A mutant the catalytic efficiency was the same with both coenyzmes, while for the R279E mutant the catalytic efficiency was 5-fold higher with NADH. The effects are mainly due to an increase in the KD values, as no major changes on the kcat or flavin reduction values were observed. Thus, the absence of a positive charge leads to no coenzyme selectivity while introduction of a negative charge leads to preference for NADH. Flavin fluorescence studies suggest altered interaction between the flavin and NADP⁺ in the mutant enzymes. The effects are caused by different binding modes of the coenzyme upon removal of the positive charge at position 279, as no major conformational changes were observed in the structure for R279A. The results indicate that the positive charge at position 279 is critical for tight binding of NADPH and efficient hydroxylation. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. The dogfish shark (Squalus acanthias) increases both hepatic and extrahepatic ornithine urea cycle enzyme activities for nitrogen conservation after feeding.

    Science.gov (United States)

    Kajimura, Makiko; Walsh, Patrick J; Mommsen, Thomas P; Wood, Chris M

    2006-01-01

    Urea not only is utilized as a major osmolyte in marine elasmobranchs but also constitutes their main nitrogenous waste. This study investigated the effect of feeding, and thus elevated nitrogen intake, on nitrogen metabolism in the Pacific spiny dogfish Squalus acanthias. We determined the activities of ornithine urea cycle (O-UC) and related enzymes in liver and nonhepatic tissues. Carbamoyl phosphate synthetase III (the rate-limiting enzyme of the O-UC) activity in muscle is high compared with liver, and the activities in both tissues increased after feeding. The contribution of muscle to urea synthesis in the dogfish body appears to be much larger than that of liver when body mass is considered. Furthermore, enhanced activities of the O-UC and related enzymes (glutamine synthetase, ornithine transcarbamoylase, arginase) were seen after feeding in both liver and muscle and were accompanied by delayed increases in plasma urea, trimethylamine oxide, total free amino acids, alanine, and chloride concentrations, as well as in total osmolality. The O-UC and related enzymes also occurred in the intestine but showed little change after feeding. Feeding did not change the rate of urea excretion, indicating strong N retention after feeding. Ammonia excretion, which constituted only a small percentage of total N excretion, was raised in fed fish, while plasma ammonia did not change, suggesting that excess ammonia in plasma is quickly ushered into synthesis of urea or protein. In conclusion, we suggest that N conservation is a high priority in this elasmobranch and that feeding promotes ureogenesis and growth. Furthermore, exogenous nitrogen from food is converted into urea not only by the liver but also by the muscle and to a small extent by the intestine.

  9. Control of utilization of L-arginine, L-ornithine, agmatine, and putrescine as nitrogen sources in Escherichia coli K-12.

    OpenAIRE

    Shaibe, E; Metzer, E; Halpern, Y S

    1985-01-01

    The regulation of the synthesis of the enzymes involved in the utilization of L-arginine, L-ornithine, agmatine, and putrescine as a sole nitrogen source in Escherichia coli K-12 was examined. The synthesis of agmatine ureohydrolase, putrescine aminotransferase, and pyrroline dehydrogenase is dually controlled by catabolite repression and nitrogen availability. Catabolite repression of agmatine ureohydrolase, but not that of putrescine aminotransferase or pyrroline dehydrogenase, is relieved ...

  10. The ArcD1 and ArcD2 arginine/ornithine exchangers encoded in the arginine deiminase (ADI) pathway gene cluster of Lactococcus lactis

    NARCIS (Netherlands)

    Noens, Elke E E; Kaczmarek, Michał B; Żygo, Monika; Lolkema, Juke S

    2015-01-01

    The arginine deiminase pathway (ADI) gene cluster in Lactococcus lactis contains two copies of a gene encoding an L-arginine/L-ornithine exchanger, the arcD1 and arcD2 genes. The physiological function of ArcD1 and ArcD2 was studied by deleting the two genes. Deletion of arcD1 resulted in loss of

  11. Structural Basis for Recognition of L-lysine, L-ornithine, and L-2,4-diamino Butyric Acid by Lysine Cyclodeaminase.

    Science.gov (United States)

    Min, Kyungjin; Yoon, Hye-Jin; Matsuura, Atsushi; Kim, Yong Hwan; Lee, Hyung Ho

    2018-04-30

    L-pipecolic acid is a non-protein amino acid commonly found in plants, animals, and microorganisms. It is a well-known precursor to numerous microbial secondary metabolites and pharmaceuticals, including anticancer agents, immunosuppressants, and several antibiotics. Lysine cyclodeaminase (LCD) catalyzes β-deamination of L-lysine into L-pipecolic acid using β-nicotinamide adenine dinucleotide as a cofactor. Expression of a human homolog of LCD, μ-crystallin, is elevated in prostate cancer patients. To understand the structural features and catalytic mechanisms of LCD, we determined the crystal structures of Streptomyces pristinaespiralis LCD (SpLCD) in (i) a binary complex with NAD + , (ii) a ternary complex with NAD + and L-pipecolic acid, (iii) a ternary complex with NAD + and L-proline, and (iv) a ternary complex with NAD + and L-2,4-diamino butyric acid. The overall structure of SpLCD was similar to that of ornithine cyclodeaminase from Pseudomonas putida . In addition, SpLCD recognized L-lysine, L-ornithine, and L-2,4-diamino butyric acid despite differences in the active site, including differences in hydrogen bonding by Asp236, which corresponds with Asp228 from Pseudomonas putida ornithine cyclodeaminase. The substrate binding pocket of SpLCD allowed substrates smaller than lysine to bind, thus enabling binding to ornithine and L-2,4-diamino butyric acid. Our structural and biochemical data facilitate a detailed understanding of substrate and product recognition, thus providing evidence for a reaction mechanism for SpLCD. The proposed mechanism is unusual in that NAD + is initially converted into NADH and then reverted back into NAD + at a late stage of the reaction.

  12. The effect of different doses of epidermal growth factor on liver ornithine decarboxylase and Na-K ATPase activities in newborn rats.

    Science.gov (United States)

    Bilgihan, A; Turkozkan, N; Isman, F; Kilinc, M; Demirsoy, S

    1998-08-01

    1. Ornithine decarboxylase and Na-K ATPase activities were studied in rat livers that were treated with different doses of epidermal growth factor (EGF). 2. The ornithine decarboxylase activities were studied with spectrophotometry, and results were expressed as micromoles of putrescine per hour per milligram of protein. Na-K ATPase activities were studied on the basis of the principle of measuring the amount of inorganic phosphates released by the hydrolysis of ATP, and the results were expressed as micromoles of inorganic phosphate per hour per milligram of protein. 3. When compared with the controls, although the Na-K ATPase activities were decreased at low doses of EGF, their activities were found to be increased at high doses of EGF. On the other hand, there was a positive correlation between ornithine decarboxylase activities and EGF doses. 4. The results of this study suggest that, whereas the decrease in Na-K ATPase activities at low doses of EGF can be due to the utilization of the enzyme, the increase in Na-K ATPase activities at high doses of EGF can be attributed to its enhanced synthesis.

  13. Cyclobutane-type pyrimidine photodimer formation and induction of ornithine decarboxylase in human skin fibroblasts after UV irradiation

    International Nuclear Information System (INIS)

    Niggli, H.J.; Roethlisberger, R.

    1988-01-01

    Cyclobutane-type pyrimidine photodimers as well as the induction of ornithine decarboxylase (ODC) may serve as biochemical markers of the mutagenic and carcinogenic effects of ultraviolet light (UV). For this reason, it is important to compare the formation of pyrimidine dimers with the induction of ODC in human skin fibroblasts after irradiation with UVC (200-290 nm) and UVB (290-320 nm). In our studies we determined cytosine-thymine (C-T) as well as thymine-thymine dimer yields (T-T) by high-pressure liquid chromatography in cultures of neonatal normal human foreskin-derived fibroblasts after irradiation with UVC and UVB light. It was found that the yield of dimerization and the ratio of T-T/C-T decreased from the UVC to the UVB region. Time-course studies of ODC-induction in the same cells indicated that the maximal activity after UVB irradiation was retarded compared to UVC exposure. For the UV-induced ODC-levels, however, no significant difference in maximal induction could be measured after UVC and UVB irradiation at fluences where comparable yields of thymine dimerization are produced. Similar ODC-maxima were obtained with strains from children, while cells from adults showed significantly less pronounced ODC induction, indicating that ODC-response decreases with age and may therefore be used as a marker of aging

  14. Heterologous Production of Cyanobacterial Mycosporine-Like Amino Acids Mycosporine-Ornithine and Mycosporine-Lysine in Escherichia coli

    Science.gov (United States)

    Katoch, Meenu; Mazmouz, Rabia; Chau, Rocky; Pearson, Leanne A.; Pickford, Russell

    2016-01-01

    ABSTRACT Mycosporine-like amino acids (MAAs) are an important class of secondary metabolites known for their protection against UV radiation and other stress factors. Cyanobacteria produce a variety of MAAs, including shinorine, the active ingredient in many sunscreen creams. Bioinformatic analysis of the genome of the soil-dwelling cyanobacterium Cylindrospermum stagnale PCC 7417 revealed a new gene cluster with homology to MAA synthase from Nostoc punctiforme. This newly identified gene cluster is unusual because it has five biosynthesis genes (mylA to mylE), compared to the four found in other MAA gene clusters. Heterologous expression of mylA to mylE in Escherichia coli resulted in the production of mycosporine-lysine and the novel compound mycosporine-ornithine. To our knowledge, this is the first time these compounds have been heterologously produced in E. coli and structurally characterized via direct spectral guidance. This study offers insight into the diversity, biosynthesis, and structure of cyanobacterial MAAs and highlights their amenability to heterologous production methods. IMPORTANCE Mycosporine-like amino acids (MAAs) are significant from an environmental microbiological perspective as they offer microbes protection against a variety of stress factors, including UV radiation. The heterologous expression of MAAs in E. coli is also significant from a biotechnological perspective as MAAs are the active ingredient in next-generation sunscreens. PMID:27520810

  15. Knocking out Ornithine Decarboxylase Antizyme 1 (OAZ1 Improves Recombinant Protein Expression in the HEK293 Cell Line

    Directory of Open Access Journals (Sweden)

    Laura Abaandou

    2018-06-01

    Full Text Available Creating efficient cell lines is a priority for the biopharmaceutical industry, which produces biologicals for various uses. A recent approach to achieving this goal is the use of non-coding RNAs, microRNA (miRNA and small interfering RNA (siRNA, to identify key genes that can potentially improve production or growth. The ornithine decarboxylase antizyme 1 (OAZ1 gene, a negative regulator of polyamine biosynthesis, was identified in a genome-wide siRNA screen as a potential engineering target, because its knock down by siRNA increased recombinant protein expression from human embryonic kidney 293 (HEK293 cells by two-fold. To investigate this further, the OAZ1 gene in HEK293 cells was knocked out using CRISPR genome editing. The OAZ1 knockout cell lines displayed up to four-fold higher expression of both stably and transiently expressed proteins, with comparable growth and metabolic activity to the parental cell line; and an approximately three-fold increase in intracellular polyamine content. The results indicate that genetic inactivation of OAZ1 in HEK293 cells is an effective strategy to improve recombinant protein expression in HEK293 cells.

  16. Comparison of the effects of an ornithine decarboxylase inhibitor on the intestinal epithelium and on intestinal tumors.

    Science.gov (United States)

    Tutton, P J; Barkla, D H

    1986-12-01

    Ornithine decarboxylase (ODC) catalyzes the rate-limiting step in the synthesis of polyamines, it has a short half-life, and its synthesis is under hormonal control. Recently, insight into the role of ODC and thus into the physiology of polyamines has been gained by the use of an inhibitor of ODC, difluoromethylornithine (DFMO). In the present report cell proliferation was measured by a stathmokinetic method in the crypt epithelium of the jejunum and colon of normal rats and in dimethylhydrazine-induced colonic tumors. Growth of human colon tumor xenografts in immunosuppressed mice and mouse colon tumor isografts was also assessed. Cell proliferation in primary colonic tumors was substantially suppressed by a single dose of DFMO at 100 mg/kg whereas the normal crypt epithelium of the small and large intestine required two doses at 400 mg/kg to produce a similar magnitude of inhibition of cell proliferation. DFMO was also found to suppress cell proliferation in, and the growth of, the transplantable colon cancers. Because of the apparent selectivity of the antimitotic activity of DFMO towards tumors, ODC inhibitors may prove to be useful anticancer drugs.

  17. Ornithine aminotransferase (OAT): recombination between an X-linked OAT sequence (7.5 kb) and the Norrie disease locus.

    Science.gov (United States)

    Ngo, J T; Bateman, J B; Spence, M A; Cortessis, V; Sparkes, R S; Kivlin, J D; Mohandas, T; Inana, G

    1990-01-01

    A human ornithine aminotransferase (OAT) locus has been mapped to the Xp11.2, as has the Norrie disease locus. We used a cDNA probe to investigate a 3-generation UCLA family with Norrie disease; a 4.2-kb RFLP was detected and a maximum lod score of 0.602 at zero recombination fraction was calculated. We used the same probe to study a second multigeneration family with Norrie disease from Utah. A different RFLP of 7.5 kb in size was identified and a recombinational event between the OAT locus represented by this RFLP and the disease loci was observed. Linkage analysis of these two loci in this family revealed a maximum load score of 1.88 at a recombination fraction of 0.10. Although both families have affected members with the same disease, the lod scores are reported separately because the 4.2- and 7.5-kb RFLPs may represent two different loci for the X-linked OAT.

  18. Different signaling pathways induced by alpha-CD3 monoclonal antibody versus alloantigen on the basis of differential ornithine sensitivity.

    Science.gov (United States)

    Mehrotra nee Tandon, P; Lind, D S; Bear, H D; Susskind, B M

    1992-08-01

    Previously we reported that 10 mM ornithine (Orn) selectively inhibits the development of CD8+ CTL in MLC. Herein we show that induction by alpha-CD3 mAb of CD8+ killer cells which manifest antibody-redirected cytotoxicity (ARC) of FcR+ targets is not Orn sensitive. Orn resistance was independent of activation kinetics or alpha-CD3 mAb concentration. alpha-CD3 mAb added to the cytotoxicity assay did not reveal a cytolytic potential in CTL from an Orn-treated MLC when the target cells bore both the inducing alloantigen and FcR. Addition of alpha-CD3 mAb to MLC failed to overcome Orn inhibition of CTL and yet induced ARC activity in the same culture. Expression of mRNA for pore-forming proteins (PFP) and granzyme B was inhibited by Orn in CTL but not in ARC killer cells. Our results demonstrate differences in the T cell activation process stimulated by alloantigen or alpha-CD3 mAb.

  19. A randomized, double-masked, placebo-controlled crossover trial on the effects of L-ornithine on salivary cortisol and feelings of fatigue of flushers the morning after alcohol consumption

    Directory of Open Access Journals (Sweden)

    Kokubo Takeshi

    2013-02-01

    Full Text Available Abstract Background Residual alcohol effects on physiological and psychological symptoms are commonly experienced the morning after alcohol consumption. The purpose of this study was to assess the effects of L-ornithine on subjective feelings and salivary stress markers the morning after alcohol consumption and to investigate whether L-ornithine acutely accelerates ethanol metabolism. Methods This study had a randomized, placebo-controlled, double-masked crossover design. Subjects were all healthy Japanese adults with the ‘flusher’ phenotype for alcohol tolerance. In experiment 1, 11 subjects drank 0.4 g/kg body weight alcohol 1.5 h before their usual bedtime. Half an hour after drinking, they ingested either a placebo or 400 mg ornithine. The next morning on awakening, subjects completed a questionnaire containing a visual analog scale (VAS, the Oguri-Shirakawa-Azumi sleep inventory MA version (OSA-MA, and a profile of mood states (POMS and collected a saliva sample for measurement of salivary stress markers (cortisol, secretory immunoglobulin A, and α-amylase. In experiment 2, placebo or 400 mg ornithine were administrated to 16 subjects both before and after drinking, and the feeling of drunkenness, breath ethanol concentration and one-leg standing time were repeatedly investigated until 180 min after alcohol consumption. Results There were significant decreases in “awareness”, “feeling of fatigue” and “lassitude” VAS scores and in “anger-hostility” and “confusion” POMS scores and a significant increase in “sleep length” in the OSA-MA test. Salivary cortisol concentrations on awakening were reduced after ornithine supplementation. There were no differences between ornithine and placebo in any of the subjective or physiological parameters of acute alcohol metabolism. Conclusions Taking 400 mg ornithine after alcohol consumption improved various negative feelings and decreased the salivary stress marker cortisol the

  20. Effect of short-term ornithine alpha-ketoglutarate pretreatment on intestinal ischemia-reperfusion in rats.

    Science.gov (United States)

    Gonçalves, Eduardo Silvio Gouveia; Rabelo, Camila Menezes; Prado Neto, Alberico Ximenes do; Garcia, José Huygens Parente; Guimarães, Sérgio Botelho; Vasconcelos, Paulo Roberto Leitão de

    2011-01-01

    To investigate the effects of preventive enteral administration of ornithine alpha-ketoglutarate (OKG) in an ischemia-reperfusion rat model. Sixty rats were randomized into five groups (G1-G5, n = 12). Each group was divided into two subgroups (n = 6) and treated with calcium carbonate (CaCa) or OKG by gavage. Thirty minutes later, the animals were anesthetized with xylazine 15mg + ketamine 1mg ip and subjected to laparotomy. G1-G3 rats served as controls. Rats in groups G4 and G5 were subjected to ischemia for 30 minutes. Ischemia was achieved by clamping the small intestine and its mesentery, delimiting a segment of bowel 5 cm long and 5 cm apart from the ileocecal valve. In addition, G5 rats underwent reperfusion for 30 minutes. Blood samples were collected at the end of the laparotomy (G1), after 30 minutes (G2, G4) and 60 minutes (G3, G5) to determine concentrations of metabolites (pyruvate, lactate), creatine phosphokinase (CPK), thiobarbituric acid reactive substances (TBARS) and glutathione (GSH). There was a significant decrease in tissue pyruvate and lactate and plasma CPK levels in OKG-treated rats at the end of reperfusion period. GSH levels did not change significantly in ischemia and reperfusion groups. However, TBARS levels increased significantly (p<0.05) in tissue samples in OKG-treated rats subjected to ischemia for 30 minutes. Short-term pretreatment with OKG before induction of I/R decreases tissue damage, increases pyruvate utilization for energy production in the Krebs cycle and does not attenuate the oxidative stress in this animal model.

  1. Efficacy of l-ornithine-l-aspartate as an adjuvant therapy in cirrhotic patients with hepatic encephalopathy

    International Nuclear Information System (INIS)

    Abid, S.; Jafri, W.; Mumtaz, K.; Islam, M.; Abbas, Z.

    2011-01-01

    To evaluate the efficacy of L-ornithine-L-aspartate (LOLA) as an adjuvant therapy in cirrhotic patients with hepatic encephalopathy (HE). Study Design: Randomized placebo controlled study. Place and Duration of Study: The Aga Khan University Hospital, Karachi in the year 2003-2004. Methodology: Patients with HE were randomized to receive LOLA or placebo medicine as an adjuvant to treatment of HE. Number connection test-A (NCT-A), ammonia level, clinical grade of HE and duration of hospitalization were assessed. Results: Out of 120 patients, there were 62 males with mean age of 57 +- 11 years. Improvement in HE was higher (n=40, 66.7%) in LOLA group as compared to the placebo group (n=28, 46.7%, p=0.027). In patients with grade I or less encephalopathy, improvement was seen in 6 (35.3%) and 3 (20%) patients in LOLA and placebo groups respectively (p=0.667). Patients with HE grade II and above showed improvement in 34 (79.1%) and 25 (55.6%) cases in LOLA and placebo group respectively (p=0.019). On multivariate analysis patients with HE of grade II and above showed prothrombin time, creatinine level and use of LOLA influencing the outcome. Duration of hospitalization was 93.6 +- 25.7 hours and 135.2 +- 103.5 hours in LOLA and placebo groups respectively (p=0.025). No side effects were observed in either groups. Conclusion: In cirrhotic patients with advanced hepatic encephalopathy treatment with LOLA was safe and associated with relatively rapid improvement and shorter hospital stay. (author)

  2. Plackett-Burman and Box-Behnken designs as chemometric tools for micro-determination of L-Ornithine

    Science.gov (United States)

    Elazazy, Marwa S.; El-Hamshary, Marwa; Sakr, Marwa; Al-Easa, Hala S.

    2018-03-01

    Plackett-Burman (PB) and Box-Behnken (BB) screening and response surface factorial designs were used to evaluate spectrophotometric and spectrofluorimetric approaches for the determination of L-Ornithine (ORN) as per se and in dietary supplements. Both approaches were based on the derivatization of the primary amino group of ORN via Hantzsch condensation reaction producing yellow coloured adducts (dihydrolutidine derivative). The reaction product was determined spectrophotometrically (method A) at λmax = 327 nm and spectrofluorimetrically (method B) at 480 nm (λem) after excitation at 325 nm (λex). A multivariate scheme was tailored to investigate the process numerical variables; reaction temperature, heating time, reagent volume, and pH implementing PB as a screening design followed by BB as an optimization strategy. Categorical factors including diluting solvent and sequence of addition were kept invariable. Responses of the reaction systems were the maximum absorbance (Y1) and maximum fluorescence intensity (Y2), correspondingly. Quality tools as well as ANOVA testing, before and after response transformation were used to decide upon the substantial variables. Following the optimization of reaction variables using desirability plots, calibration graphs were found to be rectilinear in the range of 6-14 μg/mL and 0.4-1.2 μg/mL for methods A and B, respectively. Both methods proved to be sensitive with detection limits (DL) of 337 and 85 ng/mL, and quantitation limits (QL) of 1086 and 283 ng/mL, for methods A and B, respectively. An interference study was performed using potential foreign species. No significant interference effect was observed on any of the proposed procedures. System performance was addressed following ICH guidelines and considering parameters such as linearity, detection and quantification limits, accuracy and precision, robustness and specificity.

  3. Novel type of ornithine-glutathione double conjugate excreted as a major metabolite into the bile of rats administered clebopride

    International Nuclear Information System (INIS)

    Ishizuka, T.; Komiya, I.; Hiratsuka, A.; Watabe, T.

    1990-01-01

    Rats orally given radioactive Clebopride [[14C]CP; N-(1'-benzyl-4'-piperidyl)-2-[14C]methoxy-4-amino-5-chlorobenzamide++ +], an antiulcer agent, excreted a novel type of ornithine (Orn)-GSH double conjugate in the bile as a major metabolite [(14C]BMCP), corresponding to 18% of the dose. The present study provides the first evidence for Orn conjugation of a xenobiotic in mammals and demonstrates that the structure of the radioactive conjugate differs fundamentally from those known in birds and reptiles. The structure of the biliary metabolite, [14C]BMCP, purified to homogeneity by silica gel thin layer and reverse phase high pressure liquid chromatography, was elucidated as S-[2-ornithylamino-4-[14C]methoxy-5-(1'-methyl-4'-piperidylamin o) carboxyphenyl]glutathione, based mainly on the following facts: (1) BMCP showed a protonated molecular ion (M + H)+ peak at m/z 683 in the secondary ion mass spectrum and (2) [14C]BMCP afforded Orn, glutamic acid, glycine, S-(2-amino-4-[14C]methoxy-5-carboxyphenyl)cysteine [( 14C]AMCC), and 1-methyl-4-aminopiperidine (MAP) quantitatively, in an equal molar ratio, by complete hydrolysis with peptidase. Thus, BMCP was a metabolite with three enzymatically hydrolyzable amide bonds in addition to the one existing originally in the parent structure of the drug, which produces MAP by peptic digestion. Of the three additional amide bonds of BMCP, one was a novel type of bond formed by condensation of the alpha-carboxylic acid group of Orn with the primary aromatic amino group of the drug and the other two were in the S-glutathionyl residue, substituted for the chlorine atom vicinal to the Orn-conjugating primary amino group in the aromatic ring and affording glutamic acid, glycine, and the S-cysteine conjugate AMCC by hydrolysis of BMCP with the peptidase

  4. Novel type of ornithine-glutathione double conjugate excreted as a major metabolite into the bile of rats administered clebopride.

    Science.gov (United States)

    Ishizuka, T; Komiya, I; Hiratsuka, A; Watabe, T

    1990-06-01

    Rats orally given radioactive Clebopride [[14C]CP; N-(1'-benzyl-4'-piperidyl)-2-[14C]methoxy-4-amino-5-chlorobenzamide++ +], an antiulcer agent, excreted a novel type of ornithine (Orn)-GSH double conjugate in the bile as a major metabolite [( 14C]BMCP), corresponding to 18% of the dose. The present study provides the first evidence for Orn conjugation of a xenobiotic in mammals and demonstrates that the structure of the radioactive conjugate differs fundamentally from those known in birds and reptiles. The structure of the biliary metabolite, [14C]BMCP, purified to homogeneity by silica gel thin layer and reverse phase high pressure liquid chromatography, was elucidated as S-[2-ornithylamino-4-[14C]methoxy-5-(1'-methyl-4'-piperidylamin o) carboxyphenyl]glutathione, based mainly on the following facts: 1) BMCP showed a protonated molecular ion (M + H)+ peak at m/z 683 in the secondary ion mass spectrum and 2) [14C]BMCP afforded Orn, glutamic acid, glycine, S-(2-amino-4-[14C]methoxy-5-carboxyphenyl)cysteine [( 14C]AMCC), and 1-methyl-4-aminopiperidine (MAP) quantitatively, in an equal molar ratio, by complete hydrolysis with peptidase. Thus, BMCP was a metabolite with three enzymatically hydrolyzable amide bonds in addition to the one existing originally in the parent structure of the drug, which produces MAP by peptic digestion. Of the three additional amide bonds of BMCP, one was a novel type of bond formed by condensation of the alpha-carboxylic acid group of Orn with the primary aromatic amino group of the drug and the other two were in the S-glutathionyl residue, substituted for the chlorine atom vicinal to the Orn-conjugating primary amino group in the aromatic ring and affording glutamic acid, glycine, and the S-cysteine conjugate AMCC by hydrolysis of BMCP with the peptidase. Substitution of a methyl group for the benzyl group at the piperidine ring nitrogen atom, leading to the formation of MAP by peptic digestion, also occurred during metabolism of CP to

  5. Ornithine Decarboxylase-Mediated Production of Putrescine Influences Ganoderic Acid Biosynthesis by Regulating Reactive Oxygen Species in Ganoderma lucidum.

    Science.gov (United States)

    Wu, Chen-Gao; Tian, Jia-Long; Liu, Rui; Cao, Peng-Fei; Zhang, Tian-Jun; Ren, Ang; Shi, Liang; Zhao, Ming-Wen

    2017-10-15

    Putrescine is an important polyamine that participates in a variety of stress responses. Ornithine decarboxylase (ODC) is a key enzyme that catalyzes the biosynthesis of putrescine. A homolog of the gene encoding ODC was cloned from Ganoderma lucidum In the ODC -silenced strains, the transcript levels of the ODC gene and the putrescine content were significantly decreased. The ODC -silenced strains were more sensitive to oxidative stress. The content of ganoderic acid was increased by approximately 43 to 46% in the ODC -silenced strains. The content of ganoderic acid could be recovered after the addition of exogenous putrescine. Additionally, the content of reactive oxygen species (ROS) was significantly increased by approximately 1.3-fold in the ODC -silenced strains. The ROS content was significantly reduced after the addition of exogenous putrescine. The gene transcript levels and the activities of four major antioxidant enzymes were measured to further explore the effect of putrescine on the intracellular ROS levels. Further studies showed that the effect of the ODC-mediated production of putrescine on ROS might be a factor influencing the biosynthesis of ganoderic acid. Our study reports the role of putrescine in large basidiomycetes, providing a basis for future studies of the physiological functions of putrescine in microbes. IMPORTANCE It is well known that ODC and the ODC-mediated production of putrescine play an important role in resisting various environmental stresses, but there are few reports regarding the mechanisms underlying the effect of putrescine on secondary metabolism in microorganisms, particularly in fungi. G. lucidum is gradually becoming a model organism for studying environmental regulation and metabolism. In this study, a homolog of the gene encoding ODC was cloned in Ganoderma lucidum We found that the transcript level of the ODC gene and the content of putrescine were significantly decreased in the ODC -silenced strains. The content of

  6. Partial tooth gear bearings

    Science.gov (United States)

    Vranish, John M. (Inventor)

    2010-01-01

    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  7. A Molecular Dynamics (MD and Quantum Mechanics/Molecular Mechanics (QM/MM Study on Ornithine Cyclodeaminase (OCD: A Tale of Two Iminiums

    Directory of Open Access Journals (Sweden)

    James W. Gauld

    2012-10-01

    Full Text Available Ornithine cyclodeaminase (OCD is an NAD+-dependent deaminase that is found in bacterial species such as Pseudomonas putida. Importantly, it catalyzes the direct conversion of the amino acid L-ornithine to L-proline. Using molecular dynamics (MD and a hybrid quantum mechanics/molecular mechanics (QM/MM method in the ONIOM formalism, the catalytic mechanism of OCD has been examined. The rate limiting step is calculated to be the initial step in the overall mechanism: hydride transfer from the L-ornithine’s Cα–H group to the NAD+ cofactor with concomitant formation of a Cα=NH2+ Schiff base with a barrier of 90.6 kJ mol−1. Importantly, no water is observed within the active site during the MD simulations suitably positioned to hydrolyze the Cα=NH2+ intermediate to form the corresponding carbonyl. Instead, the reaction proceeds via a non-hydrolytic mechanism involving direct nucleophilic attack of the δ-amine at the Cα-position. This is then followed by cleavage and loss of the α-NH2 group to give the Δ1-pyrroline-2-carboxylate that is subsequently reduced to L-proline.

  8. A Molecular Dynamics (MD) and Quantum Mechanics/Molecular Mechanics (QM/MM) Study on Ornithine Cyclodeaminase (OCD): A Tale of Two Iminiums

    Science.gov (United States)

    Ion, Bogdan F.; Bushnell, Eric A. C.; De Luna, Phil; Gauld, James W.

    2012-01-01

    Ornithine cyclodeaminase (OCD) is an NAD+-dependent deaminase that is found in bacterial species such as Pseudomonas putida. Importantly, it catalyzes the direct conversion of the amino acid L-ornithine to L-proline. Using molecular dynamics (MD) and a hybrid quantum mechanics/molecular mechanics (QM/MM) method in the ONIOM formalism, the catalytic mechanism of OCD has been examined. The rate limiting step is calculated to be the initial step in the overall mechanism: hydride transfer from the L-ornithine’s Cα–H group to the NAD+ cofactor with concomitant formation of a Cα=NH2 + Schiff base with a barrier of 90.6 kJ mol−1. Importantly, no water is observed within the active site during the MD simulations suitably positioned to hydrolyze the Cα=NH2 + intermediate to form the corresponding carbonyl. Instead, the reaction proceeds via a non-hydrolytic mechanism involving direct nucleophilic attack of the δ-amine at the Cα-position. This is then followed by cleavage and loss of the α-NH2 group to give the Δ1-pyrroline-2-carboxylate that is subsequently reduced to L-proline. PMID:23202934

  9. Trypanosoma cruzi Coexpressing Ornithine Decarboxylase and Green Fluorescence Proteins as a Tool to Study the Role of Polyamines in Chagas Disease Pathology

    Directory of Open Access Journals (Sweden)

    Jeremías José Barclay

    2011-01-01

    Full Text Available Polyamines are essential for Trypanosoma cruzi, the causative agent of Chagas disease. As T. cruzi behaves as a natural auxotrophic organism, it relies on host polyamines biosynthesis. In this paper we obtained a double-transfected T. cruzi parasite that expresses the green fluorescent protein (GFP and a heterologous ornithine decarboxylase (ODC, used itself as a novel selectable marker. These autotrophic and fluorescent parasites were characterized; the ODC presented an apparent Km for ornithine of 0.51 ± 0.16 mM and an estimated Vmax value of 476.2 nmoles/h/mg of protein. These expressing ODC parasites showed higher metacyclogenesis capacity than the auxotrophic counterpart, supporting the idea that polyamines are engaged in this process. This double-transfected T. cruzi parasite results in a powerful tool—easy to follow by its fluorescence—to study the role of polyamines in Chagas disease pathology and in related processes such as parasite survival, invasion, proliferation, metacyclogenesis, and tissue spreading.

  10. Maternal protein-energy malnutrition during early pregnancy in sheep impacts the fetal ornithine cycle to reduce fetal kidney microvascular development.

    Science.gov (United States)

    Dunford, Louise J; Sinclair, Kevin D; Kwong, Wing Y; Sturrock, Craig; Clifford, Bethan L; Giles, Tom C; Gardner, David S

    2014-11-01

    This paper identifies a common nutritional pathway relating maternal through to fetal protein-energy malnutrition (PEM) and compromised fetal kidney development. Thirty-one twin-bearing sheep were fed either a control (n=15) or low-protein diet (n=16, 17 vs. 8.7 g crude protein/MJ metabolizable energy) from d 0 to 65 gestation (term, ∼ 145 d). Effects on the maternal and fetal nutritional environment were characterized by sampling blood and amniotic fluid. Kidney development was characterized by histology, immunohistochemistry, vascular corrosion casts, and molecular biology. PEM had little measureable effect on maternal and fetal macronutrient balance (glucose, total protein, total amino acids, and lactate were unaffected) or on fetal growth. PEM decreased maternal and fetal urea concentration, which blunted fetal ornithine availability and affected fetal hepatic polyamine production. For the first time in a large animal model, we associated these nutritional effects with reduced micro- but not macrovascular development in the fetal kidney. Maternal PEM specifically impacts the fetal ornithine cycle, affecting cellular polyamine metabolism and microvascular development of the fetal kidney, effects that likely underpin programming of kidney development and function by a maternal low protein diet. © FASEB.

  11. EXPERIENCE OF ORNITHINE ASPARTATE (HEPA-MERZ AND PROBIOTICS BIOFLORUM FORTE IN THE TREATMENT OF NON-SEVERE FORMS OF ALCOHOLIC AND NON-ALCOHOLIC FATTY LIVER DISEASE

    Directory of Open Access Journals (Sweden)

    L. Yu. Ilchenko

    2016-01-01

    Full Text Available Aim: to evaluate the efficacy and tolerability of ornithine aspartate, probiotic Bioflorum Forte and their combination with steatosis and steatohepatitis in patients  with alcohol and non-alcoholic  fatty  liver disease. Materials and methods.  An open, randomized,  comparative  clinical study, which included 30 outpatients and inpatients with a diagnosis of steatosis, steatohepatitis. We analyzed the clinical symptoms, functional state of the liver. With the help of questionnaires  (Grids LeGo and post intoxication alcohol syndrome have established the presence of chronic alcohol intoxication. Test transmissions of numbers used to characterize the cognitive function, as well as detection  of minimal hepatic encephalopathy. Quality of life was assessed by questionnaire for patients with chronic liver disease — CLDQ (The chronic liver disease questionnaire. The duration of treatment was4 weeks. Results: all three treatment regimens have demonstrated therapeutic  efficacy: clinical improvement, recovery of liver function and results in cognitive function. When combined therapy also produced a significant improvement  in patients’ quality of life. It is shown that  the safety and tolerability of the means employed, adverse events were not reported. Conclusion: the results obtained allow us to recommend the use of ornithine aspartate (Hepa-Merz, both as monotherapy and as part of complex therapy of steatosis,  steatohepatitis with probiotic Bioflorum Forte in patients with alcoholic and non-alcoholic fatty liver disease.

  12. Essays on partial retirement

    NARCIS (Netherlands)

    Kantarci, T.

    2012-01-01

    The five essays in this dissertation address a range of topics in the micro-economic literature on partial retirement. The focus is on the labor market behavior of older age groups. The essays examine the economic and non-economic determinants of partial retirement behavior, the effect of partial

  13. Recurrent Partial Words

    Directory of Open Access Journals (Sweden)

    Francine Blanchet-Sadri

    2011-08-01

    Full Text Available Partial words are sequences over a finite alphabet that may contain wildcard symbols, called holes, which match or are compatible with all letters; partial words without holes are said to be full words (or simply words. Given an infinite partial word w, the number of distinct full words over the alphabet that are compatible with factors of w of length n, called subwords of w, refers to a measure of complexity of infinite partial words so-called subword complexity. This measure is of particular interest because we can construct partial words with subword complexities not achievable by full words. In this paper, we consider the notion of recurrence over infinite partial words, that is, we study whether all of the finite subwords of a given infinite partial word appear infinitely often, and we establish connections between subword complexity and recurrence in this more general framework.

  14. Ability of m-chloroperoxybenzoic acid to induce the ornithine decarboxylase marker of skin tumor promotion and inhibition of this response by gallotannins, oligomeric proanthocyanidins, and their monomeric units in mouse epidermis in Vivo

    Science.gov (United States)

    Guilan Chen; Elisabeth M. Perchellet; Xiao Mei Gao; Steven W. Newell; richard W. Hemingway; Vittorio Bottari; Jean-Pierre Perchellet

    1995-01-01

    m-Chloroperoxybenzoic acid (CPBA) was tested for its ability to induce the ornithine decarboxylase (ODC) marker of skin tumor promotion. In contrast to benzoyl peroxide, dicumyl peroxide, and 2-butanol peroxide, 5 mg of CPBA applied twice at a 72-h interval induce ODC activity at least as much as 3 ug of 12-O-tetradecanoylphorbol-13-acetate (TPA). ODC induction peaks...

  15. Characterization of molecular associations involving L-ornithine and α-ketoglutaric acid: crystal structure of L-ornithinium α-ketoglutarate.

    Science.gov (United States)

    Allouchi, H; Céolin, R; Berthon, L; Tombret, F; Rietveld, I B

    2014-07-01

    The crystal structure of L-ornithinium α-ketoglutarate (C5H13N2O2, C5H5O5) has been solved by direct methods using single crystal X-ray diffraction data. It crystallizes in the monoclinic system, space group P21, unit cell parameters a=15.4326(3), b=5.2015(1), c=16.2067(3) Å and β=91.986(1)°, containing two independent pairs of molecular ions in the asymmetric unit. An extensive hydrogen-bond network and electrostatic charges due to proton transfer provide an important part of the cohesive energy of the crystal. The conformational versatility of L-ornithine and α-ketoglutaric acid is illustrated by the present results and crystal structures available from the Cambridge Structural Database. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  16. N-ω-chloroacetyl-L-ornithine has in-vitro activity against cancer cell lines and in-vivo activity against ascitic and solid tumors.

    Science.gov (United States)

    Vargas-Ramírez, Alba L; Medina-Enríquez, Miriam M; Cordero-Rodríguez, Neira I; Ruiz-Cuello, Tatiana; Aguilar-Faisal, Leopoldo; Trujillo-Ferrara, José G; Alcántara-Farfán, Verónica; Rodríguez-Páez, Lorena

    2016-07-01

    N-ω-chloroacetyl-L-ornithine (NCAO) is an ornithine decarboxylase (ODC) inhibitor that is known to exert cytotoxic and antiproliferative effects on three neoplastic human cancer cell lines (HeLa, MCF-7, and HepG2). Here, we show that NCAO has antiproliferative activity in 13 cancer cell lines, of diverse tissue origin from human and mice, and in a mouse cancer model in vivo. All cell lines were sensitive to NCAO after 72 h of treatment (the EC50 ranged from 1 to 50.6 µmol/l). The Ca Ski cell line was the most sensitive (EC50=1.18±0.07 µmol/l) and MDA-MB-231 was the least sensitive (EC50=50.6±0.3 µmol/l). This ODC inhibitor showed selectivity for cancer cells, exerting almost no cytotoxic effect on the normal Vero cell line (EC50>1000 µmol/l). NCAO induced apoptosis and inhibited tumor cell migration in vitro. Furthermore, in vivo, this compound (at 50 and 100 mg/kg, daily intraperitoneal injection for 7 days) exerted potent antitumor activity against both solid and ascitic tumors in a mouse model using the myeloma (Ag8) cell line. At these same two doses, the toxicological evaluation showed that NCAO has no obvious systemic toxicity. The current results suggest that the antitumor activity is exerted by apoptosis related not only to a local but also a systemic cytotoxic effect exerted by NCAO on tumor cells. The applications for NCAO as an antitumor agent may be extensive; however, further studies are needed to ascertain the antitumor activity on other types of tumor in vivo and to determine the precise molecular mechanism of its activity.

  17. Hyperbolic partial differential equations

    CERN Document Server

    Witten, Matthew

    1986-01-01

    Hyperbolic Partial Differential Equations III is a refereed journal issue that explores the applications, theory, and/or applied methods related to hyperbolic partial differential equations, or problems arising out of hyperbolic partial differential equations, in any area of research. This journal issue is interested in all types of articles in terms of review, mini-monograph, standard study, or short communication. Some studies presented in this journal include discretization of ideal fluid dynamics in the Eulerian representation; a Riemann problem in gas dynamics with bifurcation; periodic M

  18. Successful removable partial dentures.

    Science.gov (United States)

    Lynch, Christopher D

    2012-03-01

    Removable partial dentures (RPDs) remain a mainstay of prosthodontic care for partially dentate patients. Appropriately designed, they can restore masticatory efficiency, improve aesthetics and speech, and help secure overall oral health. However, challenges remain in providing such treatments, including maintaining adequate plaque control, achieving adequate retention, and facilitating patient tolerance. The aim of this paper is to review the successful provision of RPDs. Removable partial dentures are a successful form of treatment for replacing missing teeth, and can be successfully provided with appropriate design and fabrication concepts in mind.

  19. Beginning partial differential equations

    CERN Document Server

    O'Neil, Peter V

    2011-01-01

    A rigorous, yet accessible, introduction to partial differential equations-updated in a valuable new edition Beginning Partial Differential Equations, Second Edition provides a comprehensive introduction to partial differential equations (PDEs) with a special focus on the significance of characteristics, solutions by Fourier series, integrals and transforms, properties and physical interpretations of solutions, and a transition to the modern function space approach to PDEs. With its breadth of coverage, this new edition continues to present a broad introduction to the field, while also addres

  20. Partial knee replacement - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100225.htm Partial knee replacement - series—Normal anatomy To use the sharing ... A.M. Editorial team. Related MedlinePlus Health Topics Knee Replacement A.D.A.M., Inc. is accredited ...

  1. Beginning partial differential equations

    CERN Document Server

    O'Neil, Peter V

    2014-01-01

    A broad introduction to PDEs with an emphasis on specialized topics and applications occurring in a variety of fields Featuring a thoroughly revised presentation of topics, Beginning Partial Differential Equations, Third Edition provides a challenging, yet accessible,combination of techniques, applications, and introductory theory on the subjectof partial differential equations. The new edition offers nonstandard coverageon material including Burger's equation, the telegraph equation, damped wavemotion, and the use of characteristics to solve nonhomogeneous problems. The Third Edition is or

  2. Partial differential equations

    CERN Document Server

    Evans, Lawrence C

    2010-01-01

    This text gives a comprehensive survey of modern techniques in the theoretical study of partial differential equations (PDEs) with particular emphasis on nonlinear equations. The exposition is divided into three parts: representation formulas for solutions; theory for linear partial differential equations; and theory for nonlinear partial differential equations. Included are complete treatments of the method of characteristics; energy methods within Sobolev spaces; regularity for second-order elliptic, parabolic, and hyperbolic equations; maximum principles; the multidimensional calculus of variations; viscosity solutions of Hamilton-Jacobi equations; shock waves and entropy criteria for conservation laws; and, much more.The author summarizes the relevant mathematics required to understand current research in PDEs, especially nonlinear PDEs. While he has reworked and simplified much of the classical theory (particularly the method of characteristics), he primarily emphasizes the modern interplay between funct...

  3. Optimization of partial search

    International Nuclear Information System (INIS)

    Korepin, Vladimir E

    2005-01-01

    A quantum Grover search algorithm can find a target item in a database faster than any classical algorithm. One can trade accuracy for speed and find a part of the database (a block) containing the target item even faster; this is partial search. A partial search algorithm was recently suggested by Grover and Radhakrishnan. Here we optimize it. Efficiency of the search algorithm is measured by the number of queries to the oracle. The author suggests a new version of the Grover-Radhakrishnan algorithm which uses a minimal number of such queries. The algorithm can run on the same hardware that is used for the usual Grover algorithm. (letter to the editor)

  4. Auxiliary partial liver transplantation

    NARCIS (Netherlands)

    C.B. Reuvers (Cornelis Bastiaan)

    1986-01-01

    textabstractIn this thesis studies on auxiliary partial liver transplantation in the dog and the pig are reported. The motive to perform this study was the fact that patients with acute hepatic failure or end-stage chronic liver disease are often considered to form too great a risk for successful

  5. Partial Remission Definition

    DEFF Research Database (Denmark)

    Andersen, Marie Louise Max; Hougaard, Philip; Pörksen, Sven

    2014-01-01

    OBJECTIVE: To validate the partial remission (PR) definition based on insulin dose-adjusted HbA1c (IDAA1c). SUBJECTS AND METHODS: The IDAA1c was developed using data in 251 children from the European Hvidoere cohort. For validation, 129 children from a Danish cohort were followed from the onset...

  6. Fundamental partial compositeness

    DEFF Research Database (Denmark)

    Sannino, Francesco; Strumia, Alessandro; Tesi, Andrea

    2016-01-01

    We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model fermions realize the partial compositeness scenario. Unde...

  7. Partially ordered models

    NARCIS (Netherlands)

    Fernandez, R.; Deveaux, V.

    2010-01-01

    We provide a formal definition and study the basic properties of partially ordered chains (POC). These systems were proposed to model textures in image processing and to represent independence relations between random variables in statistics (in the later case they are known as Bayesian networks).

  8. Partially Hidden Markov Models

    DEFF Research Database (Denmark)

    Forchhammer, Søren Otto; Rissanen, Jorma

    1996-01-01

    Partially Hidden Markov Models (PHMM) are introduced. They differ from the ordinary HMM's in that both the transition probabilities of the hidden states and the output probabilities are conditioned on past observations. As an illustration they are applied to black and white image compression where...

  9. Honesty in partial logic

    NARCIS (Netherlands)

    W. van der Hoek (Wiebe); J.O.M. Jaspars; E. Thijsse

    1995-01-01

    textabstractWe propose an epistemic logic in which knowledge is fully introspective and implies truth, although truth need not imply epistemic possibility. The logic is presented in sequential format and is interpreted in a natural class of partial models, called balloon models. We examine the

  10. Algebraic partial Boolean algebras

    International Nuclear Information System (INIS)

    Smith, Derek

    2003-01-01

    Partial Boolean algebras, first studied by Kochen and Specker in the 1960s, provide the structure for Bell-Kochen-Specker theorems which deny the existence of non-contextual hidden variable theories. In this paper, we study partial Boolean algebras which are 'algebraic' in the sense that their elements have coordinates in an algebraic number field. Several of these algebras have been discussed recently in a debate on the validity of Bell-Kochen-Specker theorems in the context of finite precision measurements. The main result of this paper is that every algebraic finitely-generated partial Boolean algebra B(T) is finite when the underlying space H is three-dimensional, answering a question of Kochen and showing that Conway and Kochen's infinite algebraic partial Boolean algebra has minimum dimension. This result contrasts the existence of an infinite (non-algebraic) B(T) generated by eight elements in an abstract orthomodular lattice of height 3. We then initiate a study of higher-dimensional algebraic partial Boolean algebras. First, we describe a restriction on the determinants of the elements of B(T) that are generated by a given set T. We then show that when the generating set T consists of the rays spanning the minimal vectors in a real irreducible root lattice, B(T) is infinite just if that root lattice has an A 5 sublattice. Finally, we characterize the rays of B(T) when T consists of the rays spanning the minimal vectors of the root lattice E 8

  11. Quantum mechanics/molecular mechanics studies on the mechanism of action of cofactor pyridoxal 5'-phosphate in ornithine 4,5-aminomutase.

    Science.gov (United States)

    Pang, Jiayun; Scrutton, Nigel S; Sutcliffe, Michael J

    2014-09-01

    A computational study was performed on the experimentally elusive cyclisation step in the cofactor pyridoxal 5'-phosphate (PLP)-dependent D-ornithine 4,5-aminomutase (OAM)-catalysed reaction. Calculations using both model systems and a combined quantum mechanics/molecular mechanics approach suggest that regulation of the cyclic radical intermediate is achieved through the synergy of the intrinsic catalytic power of cofactor PLP and the active site of the enzyme. The captodative effect of PLP is balanced by an enzyme active site that controls the deprotonation of both the pyridine nitrogen atom (N1) and the Schiff-base nitrogen atom (N2). Furthermore, electrostatic interactions between the terminal carboxylate and amino groups of the substrate and Arg297 and Glu81 impose substantial "strain" energy on the orientation of the cyclic intermediate to control its trajectory. In addition the "strain" energy, which appears to be sensitive to both the number of carbon atoms in the substrate/analogue and the position of the radical intermediates, may play a key role in controlling the transition of the enzyme from the closed to the open state. Our results provide new insights into several aspects of the radical mechanism in aminomutase catalysis and broaden our understanding of cofactor PLP-dependent reactions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Mass transfer ranking of polylysine, poly-ornithine and poly-methylene-co-guanidine microcapsule membranes using a single low molecular mass marker

    Directory of Open Access Journals (Sweden)

    Rosinski Stefan

    2003-01-01

    Full Text Available On the long way to clinical transplantable hybrid systems, comprising of cells, acting as immuno-protected bioreactors microencapsulated in a polymeric matrix and delivering desired factors (proteins, hormones, enzymes etc to the patient's body, an important step is the optimization of the microcapsule. This topic includes the selection of a proper coating membrane which could fulfil, first of all, the mass transfer as well as biocompatibility, stability and durability requirements. Three different membranes from polymerised aminoacids, formed around exactly identical alginate gel cores, were considered, concerning their mass transport properties, as potential candidates in this task. The results of the evaluation of the mass ingress and mass transfer coefficient h for the selected low molecular mass marker, vitamin B12, in poly-L-lysine (HPLL poly-L-ornithine (HPLO and poly-methylene-co-guanidine hydrochloride (HPMCG membrane alginate microcapsules demonstrate the advantage of using the mass transfer approach to a preliminary screening of various microcapsule formulations. Applying a single marker and evaluating mass transfer coefficients can help to quickly rank the investigated membranes and microcapsules according to their permeability. It has been demonstrated that HPLL, HPLO and HPMCG microcapsules differ from each other by a factor of two concerning the rate of low molecular mass marker transport. Interesting differences in mass transfer through the membrane in both directions in-out was also found, which could possibly be related to the membrane asymmetry.

  13. Identification of a Histidine Metal Ligand in the argE-Encoded N-Acetyl-L-Ornithine Deacetylase from Escherichia coli.

    Science.gov (United States)

    McGregor, Wade C; Gillner, Danuta M; Swierczek, Sabina I; Liu, Dali; Holz, Richard C

    2013-01-01

    The H355A, H355K, H80A, and H80K mutant enzymes of the argE-encoded N-acetyl-L-ornithine deacetylase (ArgE) from Escherichia coli were prepared, however, only the H355A enzyme was found to be soluble. Kinetic analysis of the Co(II)-loaded H355A exhibited activity levels that were 380-fold less than Co(II)-loaded WT ArgE. Electronic absorption spectra of Co(II)-loaded H355A-ArgE indicate that the bound Co(II) ion resides in a distorted, five-coordinate environment and Isothermal Titration Calorimetry (ITC) data for Zn(II) binding to the H355A enzyme provided a dissociation constant (K d) of 39 μM. A three-dimensional homology model of ArgE was generated using the X-ray crystal structure of the dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase (DapE) from Haemophilus influenzae confirming the assignment of H355 as well as H80 as active site ligands.

  14. Norrie disease: linkage analysis using a 4.2-kb RFLP detected by a human ornithine aminotransferase cDNA probe.

    Science.gov (United States)

    Ngo, J T; Bateman, J B; Cortessis, V; Sparkes, R S; Mohandas, T; Inana, G; Spence, M A

    1989-05-01

    Previous study has shown that the usual DNA marker for Norrie disease, the L1.28 probe which identifies the DXS7 locus, can recombine with the disease locus. In this study, we used a human ornithine aminotransferase (OAT) cDNA which detects OAT-related DNA sequences mapped to the same region on the X chromosome as that of the L1.28 probe to investigate the family with Norrie disease who exhibited the recombinational event. When genomic DNA from this family was digested with the PvuII restriction endonuclease, we found a restriction fragment length polymorphism (RFLP) of 4.2 kb in size. This fragment was absent in the affected males and cosegregated with the disease locus; we calculated a lod score of 0.602, at theta = 0.00. No deletion could be detected by chromosomal analysis or on Southern blots with other enzymes. These results suggest that one of the OAT-related sequences on the X chromosome may be in close proximity to the Norrie disease locus and represent the first report which indicates that the OAT cDNA may be useful for the identification of carrier status and/or prenatal diagnosis.

  15. Ornithine decarboxylase antizyme induces hypomethylation of genome DNA and histone H3 lysine 9 dimethylation (H3K9me2 in human oral cancer cell line.

    Directory of Open Access Journals (Sweden)

    Daisuke Yamamoto

    2010-09-01

    Full Text Available Methylation of CpG islands of genome DNA and lysine residues of histone H3 and H4 tails regulates gene transcription. Inhibition of polyamine synthesis by ornithine decarboxylase antizyme-1 (OAZ in human oral cancer cell line resulted in accumulation of decarboxylated S-adenosylmethionine (dcSAM, which acts as a competitive inhibitor of methylation reactions. We anticipated that accumulation of dcSAM impaired methylation reactions and resulted in hypomethylation of genome DNA and histone tails.Global methylation state of genome DNA and lysine residues of histone H3 and H4 tails were assayed by Methylation by Isoschizomers (MIAMI method and western blotting, respectively, in the presence or absence of OAZ expression. Ectopic expression of OAZ mediated hypomethylation of CpG islands of genome DNA and histone H3 lysine 9 dimethylation (H3K9me2. Protein level of DNA methyltransferase 3B (DNMT3B and histone H3K9me specific methyltransferase G9a were down-regulated in OAZ transfectant.OAZ induced hypomethylation of CpG islands of global genome DNA and H3K9me2 by down-regulating DNMT3B and G9a protein level. Hypomethylation of CpG islands of genome DNA and histone H3K9me2 is a potent mechanism of induction of the genes related to tumor suppression and DNA double strand break repair.

  16. Partially composite Higgs models

    DEFF Research Database (Denmark)

    Alanne, Tommi; Buarque Franzosi, Diogo; Frandsen, Mads T.

    2018-01-01

    We study the phenomenology of partially composite-Higgs models where electroweak symmetry breaking is dynamically induced, and the Higgs is a mixture of a composite and an elementary state. The models considered have explicit realizations in terms of gauge-Yukawa theories with new strongly...... interacting fermions coupled to elementary scalars and allow for a very SM-like Higgs state. We study constraints on their parameter spaces from vacuum stability and perturbativity as well as from LHC results and find that requiring vacuum stability up to the compositeness scale already imposes relevant...... constraints. A small part of parameter space around the classically conformal limit is stable up to the Planck scale. This is however already strongly disfavored by LHC results. in different limits, the models realize both (partially) composite-Higgs and (bosonic) technicolor models and a dynamical extension...

  17. Photogenic partial seizures.

    Science.gov (United States)

    Hennessy, M J; Binnie, C D

    2000-01-01

    To establish the incidence and symptoms of partial seizures in a cohort of patients investigated on account of known sensitivity to intermittent photic stimulation and/or precipitation of seizures by environmental visual stimuli such as television (TV) screens or computer monitors. We report 43 consecutive patients with epilepsy, who had exhibited a significant EEG photoparoxysmal response or who had seizures precipitated by environmental visual stimuli and underwent detailed assessment of their photosensitivity in the EEG laboratory, during which all were questioned concerning their ictal symptoms. All patients were considered on clinical grounds to have an idiopathic epilepsy syndrome. Twenty-eight (65%) patients reported visually precipitated attacks occurring initially with maintained consciousness, in some instances evolving to a period of confusion or to a secondarily generalized seizure. Visual symptoms were most commonly reported and included positive symptoms such as coloured circles or spots, but also blindness and subjective symptoms such as "eyes going funny." Other symptoms described included nonspecific cephalic sensations, deja-vu, auditory hallucinations, nausea, and vomiting. No patient reported any clear spontaneous partial seizures, and there were no grounds for supposing that any had partial epilepsy excepting the ictal phenomenology of some or all of the visually induced attacks. These findings provide clinical support for the physiological studies that indicate that the trigger mechanism for human photosensitivity involves binocularly innervated cells located in the visual cortex. Thus the visual cortex is the seat of the primary epileptogenic process, and the photically triggered discharges and seizures may be regarded as partial with secondary generalization.

  18. Arthroscopic partial medial meniscectomy

    Directory of Open Access Journals (Sweden)

    Dašić Žarko

    2011-01-01

    Full Text Available Background/Aim. Meniscal injuries are common in professional or recreational sports as well as in daily activities. If meniscal lesions lead to physical impairment they usually require surgical treatment. Arthroscopic treatment of meniscal injuries is one of the most often performed orthopedic operative procedures. Methods. The study analyzed the results of arthroscopic partial medial meniscectomy in 213 patients in a 24-month period, from 2006, to 2008. Results. In our series of arthroscopically treated medial meniscus tears we noted 78 (36.62% vertical complete bucket handle lesions, 19 (8.92% vertical incomplete lesions, 18 (8.45% longitudinal tears, 35 (16.43% oblique tears, 18 (8.45% complex degenerative lesions, 17 (7.98% radial lesions and 28 (13.14% horisontal lesions. Mean preoperative International Knee Documentation Committee (IKDC score was 49.81%, 1 month after the arthroscopic partial medial meniscectomy the mean IKDC score was 84.08%, and 6 months after mean IKDC score was 90.36%. Six months after the procedure 197 (92.49% of patients had good or excellent subjective postoperative clinical outcomes, while 14 (6.57% patients subjectively did not notice a significant improvement after the intervention, and 2 (0.93% patients had no subjective improvement after the partial medial meniscectomy at all. Conclusion. Arthroscopic partial medial meniscetomy is minimally invasive diagnostic and therapeutic procedure and in well selected cases is a method of choice for treatment of medial meniscus injuries when repair techniques are not a viable option. It has small rate of complications, low morbidity and fast rehabilitation.

  19. Hierarchical partial order ranking

    International Nuclear Information System (INIS)

    Carlsen, Lars

    2008-01-01

    Assessing the potential impact on environmental and human health from the production and use of chemicals or from polluted sites involves a multi-criteria evaluation scheme. A priori several parameters are to address, e.g., production tonnage, specific release scenarios, geographical and site-specific factors in addition to various substance dependent parameters. Further socio-economic factors may be taken into consideration. The number of parameters to be included may well appear to be prohibitive for developing a sensible model. The study introduces hierarchical partial order ranking (HPOR) that remedies this problem. By HPOR the original parameters are initially grouped based on their mutual connection and a set of meta-descriptors is derived representing the ranking corresponding to the single groups of descriptors, respectively. A second partial order ranking is carried out based on the meta-descriptors, the final ranking being disclosed though average ranks. An illustrative example on the prioritisation of polluted sites is given. - Hierarchical partial order ranking of polluted sites has been developed for prioritization based on a large number of parameters

  20. Partially ordered algebraic systems

    CERN Document Server

    Fuchs, Laszlo

    2011-01-01

    Originally published in an important series of books on pure and applied mathematics, this monograph by a distinguished mathematician explores a high-level area in algebra. It constitutes the first systematic summary of research concerning partially ordered groups, semigroups, rings, and fields. The self-contained treatment features numerous problems, complete proofs, a detailed bibliography, and indexes. It presumes some knowledge of abstract algebra, providing necessary background and references where appropriate. This inexpensive edition of a hard-to-find systematic survey will fill a gap i

  1. Infinite partial summations

    International Nuclear Information System (INIS)

    Sprung, D.W.L.

    1975-01-01

    This paper is a brief review of those aspects of the effective interaction problem that can be grouped under the heading of infinite partial summations of the perturbation series. After a brief mention of the classic examples of infinite summations, the author turns to the effective interaction problem for two extra core particles. Their direct interaction is summed to produce the G matrix, while their indirect interaction through the core is summed in a variety of ways under the heading of core polarization. (orig./WL) [de

  2. On universal partial words

    OpenAIRE

    Chen, Herman Z. Q.; Kitaev, Sergey; Mütze, Torsten; Sun, Brian Y.

    2016-01-01

    A universal word for a finite alphabet $A$ and some integer $n\\geq 1$ is a word over $A$ such that every word in $A^n$ appears exactly once as a subword (cyclically or linearly). It is well-known and easy to prove that universal words exist for any $A$ and $n$. In this work we initiate the systematic study of universal partial words. These are words that in addition to the letters from $A$ may contain an arbitrary number of occurrences of a special `joker' symbol $\\Diamond\

  3. Partial differential equations

    CERN Document Server

    Agranovich, M S

    2002-01-01

    Mark Vishik's Partial Differential Equations seminar held at Moscow State University was one of the world's leading seminars in PDEs for over 40 years. This book celebrates Vishik's eightieth birthday. It comprises new results and survey papers written by many renowned specialists who actively participated over the years in Vishik's seminars. Contributions include original developments and methods in PDEs and related fields, such as mathematical physics, tomography, and symplectic geometry. Papers discuss linear and nonlinear equations, particularly linear elliptic problems in angles and gener

  4. Partial differential equations

    CERN Document Server

    Levine, Harold

    1997-01-01

    The subject matter, partial differential equations (PDEs), has a long history (dating from the 18th century) and an active contemporary phase. An early phase (with a separate focus on taut string vibrations and heat flow through solid bodies) stimulated developments of great importance for mathematical analysis, such as a wider concept of functions and integration and the existence of trigonometric or Fourier series representations. The direct relevance of PDEs to all manner of mathematical, physical and technical problems continues. This book presents a reasonably broad introductory account of the subject, with due regard for analytical detail, applications and historical matters.

  5. Partial differential equations

    CERN Document Server

    Sloan, D; Süli, E

    2001-01-01

    /homepage/sac/cam/na2000/index.html7-Volume Set now available at special set price ! Over the second half of the 20th century the subject area loosely referred to as numerical analysis of partial differential equations (PDEs) has undergone unprecedented development. At its practical end, the vigorous growth and steady diversification of the field were stimulated by the demand for accurate and reliable tools for computational modelling in physical sciences and engineering, and by the rapid development of computer hardware and architecture. At the more theoretical end, the analytical insight in

  6. Elliptic partial differential equations

    CERN Document Server

    Han, Qing

    2011-01-01

    Elliptic Partial Differential Equations by Qing Han and FangHua Lin is one of the best textbooks I know. It is the perfect introduction to PDE. In 150 pages or so it covers an amazing amount of wonderful and extraordinary useful material. I have used it as a textbook at both graduate and undergraduate levels which is possible since it only requires very little background material yet it covers an enormous amount of material. In my opinion it is a must read for all interested in analysis and geometry, and for all of my own PhD students it is indeed just that. I cannot say enough good things abo

  7. Generalized Partial Volume

    DEFF Research Database (Denmark)

    Darkner, Sune; Sporring, Jon

    2011-01-01

    Mutual Information (MI) and normalized mutual information (NMI) are popular choices as similarity measure for multimodal image registration. Presently, one of two approaches is often used for estimating these measures: The Parzen Window (PW) and the Generalized Partial Volume (GPV). Their theoret...... of view as well as w.r.t. computational complexity. Finally, we present algorithms for both approaches for NMI which is comparable in speed to Sum of Squared Differences (SSD), and we illustrate the differences between PW and GPV on a number of registration examples....

  8. Hemin inhibits cyclooxygenase-2 expression through nuclear factor-kappa B activation and ornithine decarboxylase expression in 12-O-tetradecanoylphorbol-13-acetate-treated mouse skin

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hee; Lee, Chang Ki [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Oral Cancer Research Institute, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Hwang, Young Sun [Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Park, Kwang-Kyun [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Chung, Won-Yoon [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of)], E-mail: wychung@yuhs.ac

    2008-07-03

    Inflammation induced by various stimuli has been found to be associated with increased risk for most types of human cancer. Inflammation facilitates the initiation of normal cells, as well as the growth of initiated cells and their progression to malignancy through production of proinflammatory cytokines and diverse reactive oxygen/nitrogen species. These also activate the signaling molecules that are involved in inflammation and carcinogenesis. Our previous studies have demonstrated that hemin inhibited 7,12-dimethylbenz[a]anthracene (DMBA)-induced bacterial mutagenesis and oxidative DNA damage, reduced the level of DNA-DMBA adduct and 12-O-tetradecanoylphorobl-13-acetate (TPA)-induced tumor formation in DMBA-initiated ICR mouse skin, and inhibited myeloperoxidase and ornithine decarboxylase (ODC) activity and H{sub 2}O{sub 2} formation in TPA-treated mouse skin. In the present study, to further elucidate the molecular mechanisms underlying the chemopreventive activity of hemin, its effect on the expression of ODC and cyclooxygenase (COX)-2, and the activation of nuclear factor-kappa B (NF-{kappa}B) and mitogen-activated protein kinases (MAPKs) regulating these proteins were explored in mouse skin with TPA-induced inflammation. Topically applied hemin inhibited ear edema and epidermal thickness in mice treated with TPA. Pretreatment with hemin reduced the expression of ODC and COX-2, and also reduced NF-{kappa}B activation in TPA-stimulated mouse skin. In addition, hemin suppressed the TPA-induced activation of extracellular signal-regulated protein kinase (ERK) and p38 MAPK in a dose-dependent manner. Taken together, hemin inhibited TPA-induced COX-2 expression by altering NF-{kappa}B signaling pathway via ERK and p38 MAPK, as well as TPA-induced ODC expression in mouse skin. Thereby, hemin may be an attractive candidate for a chemopreventive agent.

  9. Hemin inhibits cyclooxygenase-2 expression through nuclear factor-kappa B activation and ornithine decarboxylase expression in 12-O-tetradecanoylphorbol-13-acetate-treated mouse skin

    International Nuclear Information System (INIS)

    Park, Jae Hee; Lee, Chang Ki; Hwang, Young Sun; Park, Kwang-Kyun; Chung, Won-Yoon

    2008-01-01

    Inflammation induced by various stimuli has been found to be associated with increased risk for most types of human cancer. Inflammation facilitates the initiation of normal cells, as well as the growth of initiated cells and their progression to malignancy through production of proinflammatory cytokines and diverse reactive oxygen/nitrogen species. These also activate the signaling molecules that are involved in inflammation and carcinogenesis. Our previous studies have demonstrated that hemin inhibited 7,12-dimethylbenz[a]anthracene (DMBA)-induced bacterial mutagenesis and oxidative DNA damage, reduced the level of DNA-DMBA adduct and 12-O-tetradecanoylphorobl-13-acetate (TPA)-induced tumor formation in DMBA-initiated ICR mouse skin, and inhibited myeloperoxidase and ornithine decarboxylase (ODC) activity and H 2 O 2 formation in TPA-treated mouse skin. In the present study, to further elucidate the molecular mechanisms underlying the chemopreventive activity of hemin, its effect on the expression of ODC and cyclooxygenase (COX)-2, and the activation of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) regulating these proteins were explored in mouse skin with TPA-induced inflammation. Topically applied hemin inhibited ear edema and epidermal thickness in mice treated with TPA. Pretreatment with hemin reduced the expression of ODC and COX-2, and also reduced NF-κB activation in TPA-stimulated mouse skin. In addition, hemin suppressed the TPA-induced activation of extracellular signal-regulated protein kinase (ERK) and p38 MAPK in a dose-dependent manner. Taken together, hemin inhibited TPA-induced COX-2 expression by altering NF-κB signaling pathway via ERK and p38 MAPK, as well as TPA-induced ODC expression in mouse skin. Thereby, hemin may be an attractive candidate for a chemopreventive agent

  10. Simultaneous detection of diagnostic biomarkers of alkaptonuria, ornithine carbamoyltransferase deficiency, and neuroblastoma disease by high-performance liquid chromatography/tandem mass spectrometry.

    Science.gov (United States)

    Hsu, Wei-Yi; Chen, Ching-Ming; Tsai, Fuu-Jen; Lai, Chien-Chen

    2013-05-01

    Urinary homovanillic acid (HVA)/vanillylmandelic acid (VMA), orotic acid (OA), and homogentisic acid (HGA) are diagnostic biomarkers of neuroblastoma, ornithine carbamoyl transferase deficiency (OCTD), and alkaptonuria (AKU), respectively. In this study, a high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous quantification of HVA, VMA, OA, and HGA in urine. After sample preparation, which involved only the dilution procedure, samples were quantified by LC-MS/MS. Full-scan MS/MS mode enabled the urinary markers to be quantified with a high degree of specificity and sensitivity. Rather than using a separate enzymatic method to normalize the concentration of creatinine in urine, we quantified the level of creatinine in urine in one LC-MS run. The limits of detection were 10 μg/l for HGA, 25 μg/l for HVA/VMA, and 50 μg/l for OA with a single-to-noise ratio of 3; the limits of quantification were 50 μg/l for HVA and HGA, 100 μg/l for VMA, and 250 μg/l for OA. The linear dynamic range for quantification of the analytes covered 2 to 3 orders of magnitude, depending on the analyte. The relative standard deviation of the developed LC-MS/MS method was less than 4% for the intra-day validation and 10% for the inter-day validation. The results show that our LC-MS/MS technique is a highly sensitive and rapid method for screening for biomarkers that are diagnostic of three metabolic diseases. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Unilateral removable partial dentures.

    Science.gov (United States)

    Goodall, W A; Greer, A C; Martin, N

    2017-01-27

    Removable partial dentures (RPDs) are widely used to replace missing teeth in order to restore both function and aesthetics for the partially dentate patient. Conventional RPD design is frequently bilateral and consists of a major connector that bridges both sides of the arch. Some patients cannot and will not tolerate such an extensive appliance. For these patients, bridgework may not be a predictable option and it is not always possible to provide implant-retained restorations. This article presents unilateral RPDs as a potential treatment modality for such patients and explores indications and contraindications for their use, including factors relating to patient history, clinical presentation and patient wishes. Through case examples, design, material and fabrication considerations will be discussed. While their use is not widespread, there are a number of patients who benefit from the provision of unilateral RPDs. They are a useful treatment to have in the clinician's armamentarium, but a highly-skilled dental team and a specific patient presentation is required in order for them to be a reasonable and predictable prosthetic option.

  12. Tutorial on Online Partial Evaluation

    Directory of Open Access Journals (Sweden)

    William R. Cook

    2011-09-01

    Full Text Available This paper is a short tutorial introduction to online partial evaluation. We show how to write a simple online partial evaluator for a simple, pure, first-order, functional programming language. In particular, we show that the partial evaluator can be derived as a variation on a compositionally defined interpreter. We demonstrate the use of the resulting partial evaluator for program optimization in the context of model-driven development.

  13. Type-Directed Partial Evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1998-01-01

    Type-directed partial evaluation uses a normalization function to achieve partial evaluation. These lecture notes review its background, foundations, practice, and applications. Of specific interest is the modular technique of offline and online type-directed partial evaluation in Standard ML...

  14. Type-Directed Partial Evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1998-01-01

    Type-directed partial evaluation uses a normalization function to achieve partial evaluation. These lecture notes review its background, foundations, practice, and applications. Of specific interest is the modular technique of offline and online type-directed partial evaluation in Standard ML of ...

  15. Applied partial differential equations

    CERN Document Server

    Logan, J David

    2004-01-01

    This primer on elementary partial differential equations presents the standard material usually covered in a one-semester, undergraduate course on boundary value problems and PDEs. What makes this book unique is that it is a brief treatment, yet it covers all the major ideas: the wave equation, the diffusion equation, the Laplace equation, and the advection equation on bounded and unbounded domains. Methods include eigenfunction expansions, integral transforms, and characteristics. Mathematical ideas are motivated from physical problems, and the exposition is presented in a concise style accessible to science and engineering students; emphasis is on motivation, concepts, methods, and interpretation, rather than formal theory. This second edition contains new and additional exercises, and it includes a new chapter on the applications of PDEs to biology: age structured models, pattern formation; epidemic wave fronts, and advection-diffusion processes. The student who reads through this book and solves many of t...

  16. Inductance loop and partial

    CERN Document Server

    Paul, Clayton R

    2010-01-01

    "Inductance is an unprecedented text, thoroughly discussing "loop" inductance as well as the increasingly important "partial" inductance. These concepts and their proper calculation are crucial in designing modern high-speed digital systems. World-renowned leader in electromagnetics Clayton Paul provides the knowledge and tools necessary to understand and calculate inductance." "With the present and increasing emphasis on high-speed digital systems and high-frequency analog systems, it is imperative that system designers develop an intimate understanding of the concepts and methods in this book. Inductance is a much-needed textbook designed for senior and graduate-level engineering students, as well as a hands-on guide for working engineers and professionals engaged in the design of high-speed digital and high-frequency analog systems."--Jacket.

  17. Fundamental partial compositeness

    CERN Document Server

    Sannino, Francesco

    2016-11-07

    We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model fermions realize the partial compositeness scenario. Successful models exist because gauge quantum numbers of Standard Model fermions admit a minimal enough 'square root'. Furthermore, right-handed SM fermions have an SU(2)$_R$-like structure, yielding a custodially-protected composite Higgs. Baryon and lepton numbers arise accidentally. Standard Model fermions acquire mass at tree level, while the Higgs potential and flavor violations are generated by quantum corrections. We further discuss accidental symmetries and other dynamical features stemming from the new strongly interacting scalars. If the same phenomenology can be obtained from models without our elementary scalars, they would reappear as composite states.

  18. Fundamental partial compositeness

    International Nuclear Information System (INIS)

    Sannino, Francesco; Strumia, Alessandro; Tesi, Andrea; Vigiani, Elena

    2016-01-01

    We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model fermions realize the partial compositeness scenario. Under certain assumptions on the dynamics of the scalars, successful models exist because gauge quantum numbers of Standard Model fermions admit a minimal enough ‘square root’. Furthermore, right-handed SM fermions have an SU(2)_R-like structure, yielding a custodially-protected composite Higgs. Baryon and lepton numbers arise accidentally. Standard Model fermions acquire mass at tree level, while the Higgs potential and flavor violations are generated by quantum corrections. We further discuss accidental symmetries and other dynamical features stemming from the new strongly interacting scalars. If the same phenomenology can be obtained from models without our elementary scalars, they would reappear as composite states.

  19. Effect of short-term ornithine alpha-ketoglutarate pretreatment on intestinal ischemia-reperfusion in rats Efeitos do pré-tratamento em curto prazo com ornitina alfa-cetoglutarato na isquemia-reperfusão intestinal em ratos

    OpenAIRE

    Eduardo Silvio Gouveia Gonçalves; Camila Menezes Rabelo; Alberico Ximenes do Prado Neto; José Huygens Parente Garcia; Sérgio Botelho Guimarães; Paulo Roberto Leitão de Vasconcelos

    2011-01-01

    PURPOSE: To investigate the effects of preventive enteral administration of ornithine alpha-ketoglutarate (OKG) in an ischemia-reperfusion rat model. METHODS: Sixty rats were randomized into five groups (G1-G5, n = 12). Each group was divided into two subgroups (n = 6) and treated with calcium carbonate (CaCa) or OKG by gavage. Thirty minutes later, the animals were anesthetized with xylazine 15mg + ketamine 1mg ip and subjected to laparotomy. G1-G3 rats served as controls. Rats in groups G4 ...

  20. Partial oxidation process

    International Nuclear Information System (INIS)

    Najjar, M.S.

    1987-01-01

    A process is described for the production of gaseous mixtures comprising H/sub 2/+CO by the partial oxidation of a fuel feedstock comprising a heavy liquid hydrocarbonaceous fuel having a nickel, iron, and vanadium-containing ash or petroleum coke having a nickel, iron, and vanadium-containing ash, or mixtures thereof. The feedstock includes a minimum of 0.5 wt. % of sulfur and the ash includes a minimum of 5.0 wt. % vanadium, a minimum of 0.5 ppm nickel, and a minimum of 0.5 ppm iron. The process comprises: (1) mixing together a copper-containing additive with the fuel feedstock; wherein the weight ratio of copper-containing additive to ash in the fuel feedstock is in the range of about 1.0-10.0, and there is at least 10 parts by weight of copper for each part by weight of vanadium; (2) reacting the mixture from (1) at a temperature in the range of 2200 0 F to 2900 0 F and a pressure in the range of about 5 to 250 atmospheres in a free-flow refactory lined partial oxidation reaction zone with a free-oxygen containing gas in the presence of a temperature moderator and in a reducing atmosphere to produce a hot raw effluent gas stream comprising H/sub 2/+CO and entrained molten slag; and where in the reaction zone and the copper-containing additive combines with at least a portion of the nickel and iron constituents and sulfur found in the feedstock to produce a liquid phase washing agent that collects and transports at least a portion of the vanadium-containing oxide laths and spinels and other ash components and refractory out of the reaction zone; and (3) separating nongaseous materials from the hot raw effluent gas stream

  1. Experts' understanding of partial derivatives using the Partial Derivative Machine

    OpenAIRE

    Roundy, David; Dorko, Allison; Dray, Tevian; Manogue, Corinne A.; Weber, Eric

    2014-01-01

    Partial derivatives are used in a variety of different ways within physics. Most notably, thermodynamics uses partial derivatives in ways that students often find confusing. As part of a collaboration with mathematics faculty, we are at the beginning of a study of the teaching of partial derivatives, a goal of better aligning the teaching of multivariable calculus with the needs of students in STEM disciplines. As a part of this project, we have performed a pilot study of expert understanding...

  2. Partial Actions and Power Sets

    Directory of Open Access Journals (Sweden)

    Jesús Ávila

    2013-01-01

    Full Text Available We consider a partial action (X,α with enveloping action (T,β. In this work we extend α to a partial action on the ring (P(X,Δ,∩ and find its enveloping action (E,β. Finally, we introduce the concept of partial action of finite type to investigate the relationship between (E,β and (P(T,β.

  3. Algorithms over partially ordered sets

    DEFF Research Database (Denmark)

    Baer, Robert M.; Østerby, Ole

    1969-01-01

    in partially ordered sets, answer the combinatorial question of how many maximal chains might exist in a partially ordered set withn elements, and we give an algorithm for enumerating all maximal chains. We give (in § 3) algorithms which decide whether a partially ordered set is a (lower or upper) semi......-lattice, and whether a lattice has distributive, modular, and Boolean properties. Finally (in § 4) we give Algol realizations of the various algorithms....

  4. Anatomic partial nephrectomy: technique evolution.

    Science.gov (United States)

    Azhar, Raed A; Metcalfe, Charles; Gill, Inderbir S

    2015-03-01

    Partial nephrectomy provides equivalent long-term oncologic and superior functional outcomes as radical nephrectomy for T1a renal masses. Herein, we review the various vascular clamping techniques employed during minimally invasive partial nephrectomy, describe the evolution of our partial nephrectomy technique and provide an update on contemporary thinking about the impact of ischemia on renal function. Recently, partial nephrectomy surgical technique has shifted away from main artery clamping and towards minimizing/eliminating global renal ischemia during partial nephrectomy. Supported by high-fidelity three-dimensional imaging, novel anatomic-based partial nephrectomy techniques have recently been developed, wherein partial nephrectomy can now be performed with segmental, minimal or zero global ischemia to the renal remnant. Sequential innovations have included early unclamping, segmental clamping, super-selective clamping and now culminating in anatomic zero-ischemia surgery. By eliminating 'under-the-gun' time pressure of ischemia for the surgeon, these techniques allow an unhurried, tightly contoured tumour excision with point-specific sutured haemostasis. Recent data indicate that zero-ischemia partial nephrectomy may provide better functional outcomes by minimizing/eliminating global ischemia and preserving greater vascularized kidney volume. Contemporary partial nephrectomy includes a spectrum of surgical techniques ranging from conventional-clamped to novel zero-ischemia approaches. Technique selection should be tailored to each individual case on the basis of tumour characteristics, surgical feasibility, surgeon experience, patient demographics and baseline renal function.

  5. Partial order infinitary term rewriting

    DEFF Research Database (Denmark)

    Bahr, Patrick

    2014-01-01

    We study an alternative model of infinitary term rewriting. Instead of a metric on terms, a partial order on partial terms is employed to formalise convergence of reductions. We consider both a weak and a strong notion of convergence and show that the metric model of convergence coincides with th...... to the metric setting -- orthogonal systems are both infinitarily confluent and infinitarily normalising in the partial order setting. The unique infinitary normal forms that the partial order model admits are Böhm trees....

  6. On Degenerate Partial Differential Equations

    OpenAIRE

    Chen, Gui-Qiang G.

    2010-01-01

    Some of recent developments, including recent results, ideas, techniques, and approaches, in the study of degenerate partial differential equations are surveyed and analyzed. Several examples of nonlinear degenerate, even mixed, partial differential equations, are presented, which arise naturally in some longstanding, fundamental problems in fluid mechanics and differential geometry. The solution to these fundamental problems greatly requires a deep understanding of nonlinear degenerate parti...

  7. [Acrylic resin removable partial dentures

    NARCIS (Netherlands)

    Baat, C. de; Witter, D.J.; Creugers, N.H.J.

    2011-01-01

    An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of

  8. Partial Epilepsy with Auditory Features

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-07-01

    Full Text Available The clinical characteristics of 53 sporadic (S cases of idiopathic partial epilepsy with auditory features (IPEAF were analyzed and compared to previously reported familial (F cases of autosomal dominant partial epilepsy with auditory features (ADPEAF in a study at the University of Bologna, Italy.

  9. Partial twisting for scalar mesons

    International Nuclear Information System (INIS)

    Agadjanov, Dimitri; Meißner, Ulf-G.; Rusetsky, Akaki

    2014-01-01

    The possibility of imposing partially twisted boundary conditions is investigated for the scalar sector of lattice QCD. According to the commonly shared belief, the presence of quark-antiquark annihilation diagrams in the intermediate state generally hinders the use of the partial twisting. Using effective field theory techniques in a finite volume, and studying the scalar sector of QCD with total isospin I=1, we however demonstrate that partial twisting can still be performed, despite the fact that annihilation diagrams are present. The reason for this are delicate cancellations, which emerge due to the graded symmetry in partially quenched QCD with valence, sea and ghost quarks. The modified Lüscher equation in case of partial twisting is given

  10. Cast Partial Denture versus Acrylic Partial Denture for Replacement of Missing Teeth in Partially Edentulous Patients

    Directory of Open Access Journals (Sweden)

    Pramita Suwal

    2017-03-01

    Full Text Available Aim: To compare the effects of cast partial denture with conventional all acrylic denture in respect to retention, stability, masticatory efficiency, comfort and periodontal health of abutments. Methods: 50 adult partially edentulous patient seeking for replacement of missing teeth having Kennedy class I and II arches with or without modification areas were selected for the study. Group-A was treated with cast partial denture and Group-B with acrylic partial denture. Data collected during follow-up visit of 3 months, 6 months, and 1 year by evaluating retention, stability, masticatory efficiency, comfort, periodontal health of abutment. Results: Chi-square test was applied to find out differences between the groups at 95% confidence interval where p = 0.05. One year comparison shows that cast partial denture maintained retention and stability better than acrylic partial denture (p< 0.05. The masticatory efficiency was significantly compromising from 3rd month to 1 year in all acrylic partial denture groups (p< 0.05. The comfort of patient with cast partial denture was maintained better during the observation period (p< 0.05. Periodontal health of abutment was gradually deteriorated in all acrylic denture group (p

  11. Physics of partially ionized plasmas

    CERN Document Server

    Krishan, Vinod

    2016-01-01

    Plasma is one of the four fundamental states of matter; the other three being solid, liquid and gas. Several components, such as molecular clouds, diffuse interstellar gas, the solar atmosphere, the Earth's ionosphere and laboratory plasmas, including fusion plasmas, constitute the partially ionized plasmas. This book discusses different aspects of partially ionized plasmas including multi-fluid description, equilibrium and types of waves. The discussion goes on to cover the reionization phase of the universe, along with a brief description of high discharge plasmas, tokomak plasmas and laser plasmas. Various elastic and inelastic collisions amongst the three particle species are also presented. In addition, the author demonstrates the novelty of partially ionized plasmas using many examples; for instance, in partially ionized plasma the magnetic induction is subjected to the ambipolar diffusion and the Hall effect, as well as the usual resistive dissipation. Also included is an observation of kinematic dynam...

  12. Partially massless fields during inflation

    Science.gov (United States)

    Baumann, Daniel; Goon, Garrett; Lee, Hayden; Pimentel, Guilherme L.

    2018-04-01

    The representation theory of de Sitter space allows for a category of partially massless particles which have no flat space analog, but could have existed during inflation. We study the couplings of these exotic particles to inflationary perturbations and determine the resulting signatures in cosmological correlators. When inflationary perturbations interact through the exchange of these fields, their correlation functions inherit scalings that cannot be mimicked by extra massive fields. We discuss in detail the squeezed limit of the tensor-scalar-scalar bispectrum, and show that certain partially massless fields can violate the tensor consistency relation of single-field inflation. We also consider the collapsed limit of the scalar trispectrum, and find that the exchange of partially massless fields enhances its magnitude, while giving no contribution to the scalar bispectrum. These characteristic signatures provide clean detection channels for partially massless fields during inflation.

  13. Introduction to partial differential equations

    CERN Document Server

    Greenspan, Donald

    2000-01-01

    Designed for use in a one-semester course by seniors and beginning graduate students, this rigorous presentation explores practical methods of solving differential equations, plus the unifying theory underlying the mathematical superstructure. Topics include basic concepts, Fourier series, second-order partial differential equations, wave equation, potential equation, heat equation, approximate solution of partial differential equations, and more. Exercises appear at the ends of most chapters. 1961 edition.

  14. [Acrylic resin removable partial dentures].

    Science.gov (United States)

    de Baat, C; Witter, D J; Creugers, N H J

    2011-01-01

    An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of removable partial dentures, the acrylic resin removable partial denture has 3 favourable aspects: the economic aspect, its aesthetic quality and the ease with which it can be extended and adjusted. Disadvantages are an increased risk of caries developing, gingivitis, periodontal disease, denture stomatitis, alveolar bone reduction, tooth migration, triggering of the gag reflex and damage to the acrylic resin base. Present-day indications are ofa temporary or palliative nature or are motivated by economic factors. Special varieties of the acrylic resin removable partial denture are the spoon denture, the flexible denture fabricated of non-rigid acrylic resin, and the two-piece sectional denture. Furthermore, acrylic resin removable partial dentures can be supplied with clasps or reinforced by fibers or metal wires.

  15. Parachute technique for partial penectomy

    Directory of Open Access Journals (Sweden)

    Fernando Korkes

    2010-04-01

    Full Text Available PURPOSE: Penile carcinoma is a rare but mutilating malignancy. In this context, partial penectomy is the most commonly applied approach for best oncological results. We herein propose a simple modification of the classic technique of partial penectomy, for better cosmetic and functional results. TECHNIQUE: If partial penectomy is indicated, the present technique can bring additional benefits. Different from classical technique, the urethra is spatulated only ventrally. An inverted "V" skin flap with 0.5 cm of extension is sectioned ventrally. The suture is performed with vicryl 4-0 in a "parachute" fashion, beginning from the ventral portion of the urethra and the "V" flap, followed by the "V" flap angles and than by the dorsal portion of the penis. After completion of the suture, a Foley catheter and light dressing are placed for 24 hours. CONCLUSIONS: Several complex reconstructive techniques have been previously proposed, but normally require specific surgical abilities, adequate patient selection and staged procedures. We believe that these reconstructive techniques are very useful in some specific subsets of patients. However, the technique herein proposed is a simple alternative that can be applied to all men after a partial penectomy, and takes the same amount of time as that in the classic technique. In conclusion, the "parachute" technique for penile reconstruction after partial amputation not only improves the appearance of the penis, but also maintains an adequate function.

  16. Partial Transposition on Bipartite System

    International Nuclear Information System (INIS)

    Xi-Jun, Ren; Yong-Jian, Han; Yu-Chun, Wu; Guang-Can, Guo

    2008-01-01

    Many properties of partial transposition are unclear as yet. Here we carefully consider the number of the negative eigenvalues of ρ T (ρ's partial transposition) when ρ is a two-partite state. There is strong evidence to show that the number of negative eigenvalues of ρ T is N(N − 1)/2 at most when ρ is a state in Hilbert space C N C N . For the special case, the 2 × 2 system, we use this result to give a partial proof of the conjecture |ρ T | T ≥ 0. We find that this conjecture is strongly connected with the entanglement of the state corresponding to the negative eigenvalue of ρ T or the negative entropy of ρ

  17. Partial volume effect in MRI

    International Nuclear Information System (INIS)

    Maeda, Munehiro; Yoshiya, Kazuhiko; Suzuki, Eiji

    1989-01-01

    According to the direction and the thickness of the imaging slice in tomography, the border between the tissues becomes unclear (partial volume effect). In the present MRI experiment, we examined border area between fat and water components using phantom in order to investigate the partial volume effect in MRI. In spin echo sequences, the intensity of the border area showed a linear relationship with composition of fat and water. Whereas, in inversion recovery and field echo sequences, we found the parameters to produce an extremely low intensity area at the border region between fat and water. This low intensity area was explained by cancellation of NMR signals from fat and water due to the difference in the direction of magnetic vectors. Clinically, partial volume effect can cause of mis-evaluation of walls, small nodules, tumor capsules and the tumor invasion in the use of inversion recovery and field echo sequences. (author)

  18. Partially composite Goldstone Higgs boson

    DEFF Research Database (Denmark)

    Alanne, Tommi; Franzosi, Diogo Buarque; Frandsen, Mads T.

    2017-01-01

    We consider a model of dynamical electroweak symmetry breaking with a partially composite Goldstone Higgs boson. The model is based on a strongly interacting fermionic sector coupled to a fundamental scalar sector via Yukawa interactions. The SU(4)×SU(4) global symmetry of these two sectors...... is broken to a single SU(4) via Yukawa interactions. Electroweak symmetry breaking is dynamically induced by condensation due to the strong interactions in the new fermionic sector which further breaks the global symmetry SU(4)→Sp(4). The Higgs boson arises as a partially composite state which is an exact...... Goldstone boson in the limit where SM interactions are turned off. Terms breaking the SU(4) global symmetry explicitly generate a mass for the Goldstone Higgs boson. The model realizes in different limits both (partially) composite Higgs and (bosonic) technicolor models, thereby providing a convenient...

  19. Landsliding in partially saturated materials

    Science.gov (United States)

    Godt, J.W.; Baum, R.L.; Lu, N.

    2009-01-01

    [1] Rainfall-induced landslides are pervasive in hillslope environments around the world and among the most costly and deadly natural hazards. However, capturing their occurrence with scientific instrumentation in a natural setting is extremely rare. The prevailing thinking on landslide initiation, particularly for those landslides that occur under intense precipitation, is that the failure surface is saturated and has positive pore-water pressures acting on it. Most analytic methods used for landslide hazard assessment are based on the above perception and assume that the failure surface is located beneath a water table. By monitoring the pore water and soil suction response to rainfall, we observed shallow landslide occurrence under partially saturated conditions for the first time in a natural setting. We show that the partially saturated shallow landslide at this site is predictable using measured soil suction and water content and a novel unified effective stress concept for partially saturated earth materials. Copyright 2009 by the American Geophysical Union.

  20. Basic linear partial differential equations

    CERN Document Server

    Treves, Francois

    1975-01-01

    Focusing on the archetypes of linear partial differential equations, this text for upper-level undergraduates and graduate students features most of the basic classical results. The methods, however, are decidedly nontraditional: in practically every instance, they tend toward a high level of abstraction. This approach recalls classical material to contemporary analysts in a language they can understand, as well as exploiting the field's wealth of examples as an introduction to modern theories.The four-part treatment covers the basic examples of linear partial differential equations and their

  1. Elements of partial differential equations

    CERN Document Server

    Sneddon, Ian Naismith

    1957-01-01

    Geared toward students of applied rather than pure mathematics, this volume introduces elements of partial differential equations. Its focus is primarily upon finding solutions to particular equations rather than general theory.Topics include ordinary differential equations in more than two variables, partial differential equations of the first and second orders, Laplace's equation, the wave equation, and the diffusion equation. A helpful Appendix offers information on systems of surfaces, and solutions to the odd-numbered problems appear at the end of the book. Readers pursuing independent st

  2. Timed Testing under Partial Observability

    DEFF Research Database (Denmark)

    David, Alexandre; Larsen, Kim Guldstrand; Li, Shuhao

    2009-01-01

    observability of SUT using a set of predicates over the TGA state space, and specify the test purposes in Computation Tree Logic (CTL) formulas. A recently developed partially observable timed game solver is used to generate winning strategies, which are used as test cases. We propose a conformance testing...

  3. Variable Selection via Partial Correlation.

    Science.gov (United States)

    Li, Runze; Liu, Jingyuan; Lou, Lejia

    2017-07-01

    Partial correlation based variable selection method was proposed for normal linear regression models by Bühlmann, Kalisch and Maathuis (2010) as a comparable alternative method to regularization methods for variable selection. This paper addresses two important issues related to partial correlation based variable selection method: (a) whether this method is sensitive to normality assumption, and (b) whether this method is valid when the dimension of predictor increases in an exponential rate of the sample size. To address issue (a), we systematically study this method for elliptical linear regression models. Our finding indicates that the original proposal may lead to inferior performance when the marginal kurtosis of predictor is not close to that of normal distribution. Our simulation results further confirm this finding. To ensure the superior performance of partial correlation based variable selection procedure, we propose a thresholded partial correlation (TPC) approach to select significant variables in linear regression models. We establish the selection consistency of the TPC in the presence of ultrahigh dimensional predictors. Since the TPC procedure includes the original proposal as a special case, our theoretical results address the issue (b) directly. As a by-product, the sure screening property of the first step of TPC was obtained. The numerical examples also illustrate that the TPC is competitively comparable to the commonly-used regularization methods for variable selection.

  4. Adaptive Partially Hidden Markov Models

    DEFF Research Database (Denmark)

    Forchhammer, Søren Otto; Rasmussen, Tage

    1996-01-01

    Partially Hidden Markov Models (PHMM) have recently been introduced. The transition and emission probabilities are conditioned on the past. In this report, the PHMM is extended with a multiple token version. The different versions of the PHMM are applied to bi-level image coding....

  5. Partially molten magma ocean model

    International Nuclear Information System (INIS)

    Shirley, D.N.

    1983-01-01

    The properties of the lunar crust and upper mantle can be explained if the outer 300-400 km of the moon was initially only partially molten rather than fully molten. The top of the partially molten region contained about 20% melt and decreased to 0% at 300-400 km depth. Nuclei of anorthositic crust formed over localized bodies of magma segregated from the partial melt, then grew peripherally until they coverd the moon. Throughout most of its growth period the anorthosite crust floated on a layer of magma a few km thick. The thickness of this layer is regulated by the opposing forces of loss of material by fractional crystallization and addition of magma from the partial melt below. Concentrations of Sr, Eu, and Sm in pristine ferroan anorthosites are found to be consistent with this model, as are trends for the ferroan anorthosites and Mg-rich suites on a diagram of An in plagioclase vs. mg in mafics. Clustering of Eu, Sr, and mg values found among pristine ferroan anorthosites are predicted by this model

  6. [Posterior ceramic bonded partial restorations].

    Science.gov (United States)

    Mainjot, Amélie; Vanheusden, Alain

    2006-01-01

    Posterior ceramic bonded partial restorations are conservative and esthetic approaches for compromised teeth. Overlays constitute a less invasive alternative for tooth tissues than crown preparations. With inlays and onlays they are also indicated in case of full arch or quadrant rehabilitations including several teeth. This article screens indications and realization of this type of restorations.

  7. Implementing circularity using partial evaluation

    DEFF Research Database (Denmark)

    Lawall, Julia Laetitia

    2001-01-01

    of an imperative C-like language, by extending the language with a new construct, persistent variables. We show that an extension of partial evaluation can eliminate persistent variables, producing a staged C program. This approach has been implemented in the Tempo specializer for C programs, and has proven useful...

  8. The partial-birth stratagem.

    Science.gov (United States)

    1998-06-01

    In Wisconsin, physicians stopped performing abortions when a Federal District Court Judge refused to issue a temporary restraining order against the state's newly enacted "partial birth" abortion ban that was couched in such vague language it actually covered all abortions. While ostensibly attempting to ban late-term "intact dilation and extraction," the language of the law did not refer to that procedure or to late terms. Instead, it prohibited all abortions in which a physician "partially vaginally delivers a living child, causes the death of the partially delivered child with the intent to kill the child and then completes the delivery of the child." The law also defined "child" as "a human being from the time of fertilization" until birth. It is clear that this abortion ban is unconstitutional under Row v. Wade, and this unconstitutionality is compounded by the fact that the law allowed no exception to protect a woman's health, which is required by Roe for abortion bans after fetal viability. Wisconsin is only one of about 28 states that have enacted similar laws, and only two have restricted the ban to postviability abortions. Many of these laws have been struck down in court, and President Clinton has continued to veto the Federal partial-birth bill. The Wisconsin Judge acknowledged that opponents of the ban will likely prevail when the case is heard, but his action in denying the temporary injunction means that many women in Wisconsin will not receive timely medical care. The partial birth strategy is really only another anti-abortion strategy.

  9. The strategic value of partial vertical integration

    OpenAIRE

    Fiocco, Raffaele

    2014-01-01

    We investigate the strategic incentives for partial vertical integration, namely, partial ownership agreements between manufacturers and retailers, when retailers privately know their costs and engage in differentiated good price competition. The partial misalignment between the profit objectives within a partially integrated manufacturer-retailer hierarchy entails a higher retail price than under full integration. This `information vertical effect' translates into an opposite ...

  10. 32 CFR 751.13 - Partial payments.

    Science.gov (United States)

    2010-07-01

    ... voucher and all other information related to the partial payment shall be placed in the claim file. Action... 32 National Defense 5 2010-07-01 2010-07-01 false Partial payments. 751.13 Section 751.13 National... Claims Against the United States § 751.13 Partial payments. (a) Partial payments when hardship exists...

  11. Removable partial dentures: clinical concepts.

    Science.gov (United States)

    Bohnenkamp, David M

    2014-01-01

    This article provides a review of the traditional clinical concepts for the design and fabrication of removable partial dentures (RPDs). Although classic theories and rules for RPD designs have been presented and should be followed, excellent clinical care for partially edentulous patients may also be achieved with computer-aided design/computer-aided manufacturing technology and unique blended designs. These nontraditional RPD designs and fabrication methods provide for improved fit, function, and esthetics by using computer-aided design software, composite resin for contours and morphology of abutment teeth, metal support structures for long edentulous spans and collapsed occlusal vertical dimensions, and flexible, nylon thermoplastic material for metal-supported clasp assemblies. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Partial scram incident in FBTR

    International Nuclear Information System (INIS)

    Usha, S.; Pillai, C.P.; Muralikrishna, G.

    1989-01-01

    Evaluation of a partial scram incident occurred at the Fast Breeder Test Reactor at Kalpakkam was carried out. Based on the observations of the experiments it was ascertained that the nonpersistant order was due to superimposed noise component on the channel that was close to the threshold and had resulted in intermittent supply to electro-magnetic (EM) coils. Owing to a larger discharge time and a smaller charge time, the EM coils got progressively discharged. It was confirmed that during the incident, partial scram took place since the charging and discharging patterns of the EM coils are dissimilar and EM coils of rods A, E and F had discharged faster than others for noise component of a particular duty cycle. However, nonlatching of scram order was because of the fact that noise pulse duration was less than latching time. (author)

  13. The marketing of partial hospitalization.

    Science.gov (United States)

    Millsap, P; Brown, E; Kiser, L; Pruitt, D

    1987-09-01

    Health-care professionals are currently operating in the context of a rapidly changing health-care delivery system, including the move away from inpatient services to outpatient services in order to control costs. Those who practice in partial-hospital settings are in a position to offer effective, cost-efficient services; however, there continue to be obstacles which hinder appropriate utilization of the modality. The development and use of a well-designed marketing plan is one strategy for removing these obstacles. This paper presents a brief overview of the marketing process, ideas for developing a marketing plan, and several examples of specific marketing strategies as well as ways to monitor their effectiveness. Partial-hospital providers must take an active role in answering the calls for alternative sources of psychiatric care. A comprehensive, education-oriented marketing approach will increase the public's awareness of such alternatives and enable programs to survive in a competitive environment.

  14. Introduction to partial differential equations

    CERN Document Server

    Borthwick, David

    2016-01-01

    This modern take on partial differential equations does not require knowledge beyond vector calculus and linear algebra. The author focuses on the most important classical partial differential equations, including conservation equations and their characteristics, the wave equation, the heat equation, function spaces, and Fourier series, drawing on tools from analysis only as they arise.Within each section the author creates a narrative that answers the five questions: (1) What is the scientific problem we are trying to understand? (2) How do we model that with PDE? (3) What techniques can we use to analyze the PDE? (4) How do those techniques apply to this equation? (5) What information or insight did we obtain by developing and analyzing the PDE? The text stresses the interplay between modeling and mathematical analysis, providing a thorough source of problems and an inspiration for the development of methods.

  15. Dynamics of partial differential equations

    CERN Document Server

    Wayne, C Eugene

    2015-01-01

    This book contains two review articles on the dynamics of partial differential equations that deal with closely related topics but can be read independently. Wayne reviews recent results on the global dynamics of the two-dimensional Navier-Stokes equations. This system exhibits stable vortex solutions: the topic of Wayne's contribution is how solutions that start from arbitrary initial conditions evolve towards stable vortices. Weinstein considers the dynamics of localized states in nonlinear Schrodinger and Gross-Pitaevskii equations that describe many optical and quantum systems. In this contribution, Weinstein reviews recent bifurcations results of solitary waves, their linear and nonlinear stability properties, and results about radiation damping where waves lose energy through radiation.   The articles, written independently, are combined into one volume to showcase the tools of dynamical systems theory at work in explaining qualitative phenomena associated with two classes of partial differential equ...

  16. Partial Cooperative Equilibria: Existence and Characterization

    Directory of Open Access Journals (Sweden)

    Amandine Ghintran

    2010-09-01

    Full Text Available We study the solution concepts of partial cooperative Cournot-Nash equilibria and partial cooperative Stackelberg equilibria. The partial cooperative Cournot-Nash equilibrium is axiomatically characterized by using notions of rationality, consistency and converse consistency with regard to reduced games. We also establish sufficient conditions for which partial cooperative Cournot-Nash equilibria and partial cooperative Stackelberg equilibria exist in supermodular games. Finally, we provide an application to strategic network formation where such solution concepts may be useful.

  17. Partial dependency parsing for Irish

    OpenAIRE

    Uí Dhonnchadha, Elaine; van Genabith, Josef

    2010-01-01

    In this paper we present a partial dependency parser for Irish, in which Constraint Grammar (CG) rules are used to annotate dependency relations and grammatical functions in unrestricted Irish text. Chunking is performed using a regular-expression grammar which operates on the dependency tagged sentences. As this is the first implementation of a parser for unrestricted Irish text (to our knowledge), there were no guidelines or precedents available. Therefore deciding what constitutes a syntac...

  18. Matching games with partial information

    Science.gov (United States)

    Laureti, Paolo; Zhang, Yi-Cheng

    2003-06-01

    We analyze different ways of pairing agents in a bipartite matching problem, with regard to its scaling properties and to the distribution of individual “satisfactions”. Then we explore the role of partial information and bounded rationality in a generalized Marriage Problem, comparing the benefits obtained by self-searching and by a matchmaker. Finally we propose a modified matching game intended to mimic the way consumers’ information makes firms to enhance the quality of their products in a competitive market.

  19. High-resolution slab gel isoelectric focusing: methods for quantitative electrophoretic transfer and immunodetection of proteins as applied to the study of the multiple isoelectric forms of ornithine decarboxylase.

    Science.gov (United States)

    Reddy, S G; Cochran, B J; Worth, L L; Knutson, V P; Haddox, M K

    1994-04-01

    A high-resolution isoelectric focusing vertical slab gel method which can resolve proteins which differ by a single charge was developed and this method was applied to the study of the multiple isoelectric forms of ornithine decarboxylase. Separation of proteins at this high level of resolution was achieved by increasing the ampholyte concentration in the gels to 6%. Various lots of ampholytes, from the same or different commercial sources, differed significantly in their protein binding capacity. Ampholytes bound to proteins interfered both with the electrophoretic transfer of proteins from the gel to immunoblotting membranes and with the ability of antibodies to interact with proteins on the immunoblotting membranes. Increasing the amount of protein loaded into a gel lane also decreased the efficiency of the electrophoretic transfer and immunodetection. To overcome these problems, both gel washing and gel electrophoretic transfer protocols for disrupting the ampholyte-protein binding and enabling a quantitative electrophoretic transfer of proteins were developed. Two gel washing procedures, with either thiocyanate or borate buffers, and a two-step electrophoretic transfer method are described. The choice of which method to use to optimally disrupt the ampholyte-protein binding was found to vary with each lot of ampholytes employed.

  20. Synchronizing Strategies under Partial Observability

    DEFF Research Database (Denmark)

    Larsen, Kim Guldstrand; Laursen, Simon; Srba, Jiri

    2014-01-01

    Embedded devices usually share only partial information about their current configurations as the communication bandwidth can be restricted. Despite this, we may wish to bring a failed device into a given predetermined configuration. This problem, also known as resetting or synchronizing words, has...... been intensively studied for systems that do not provide any information about their configurations. In order to capture more general scenarios, we extend the existing theory of synchronizing words to synchronizing strategies, and study the synchronization, short-synchronization and subset...

  1. Partial differential equations an introduction

    CERN Document Server

    Colton, David

    2004-01-01

    Intended for a college senior or first-year graduate-level course in partial differential equations, this text offers students in mathematics, engineering, and the applied sciences a solid foundation for advanced studies in mathematics. Classical topics presented in a modern context include coverage of integral equations and basic scattering theory. This complete and accessible treatment includes a variety of examples of inverse problems arising from improperly posed applications. Exercises at the ends of chapters, many with answers, offer a clear progression in developing an understanding of

  2. Laparoscopic Partial Hepatectomy: Animal Experiments

    Directory of Open Access Journals (Sweden)

    Haruhiro Inoue

    1995-01-01

    Full Text Available As a first step in firmly establishing laparoscopic hepatectomy, we introduce a porcine model of laparoscopic partial hepatectomy. This procedure has been successfully performed under the normal-pressure or low-pressure pneumoperitoneum condition supported by the full-thickness abdominal wall lifting technique. An ultrasonic dissector combined with electrocautery, newly developed by Olympus Optical Corporation (Japan was effectively utilized in facilitating safe and smooth incisions into the liver parenchyma. Although indications for this procedure seem to be limited only to peripheral lesions and not to central lesions, clinical application of this method may be useful for some patients in the near future.

  3. Report of 3 Patients With Urea Cycle Defects Treated With Related Living-Donor Liver Transplant.

    Science.gov (United States)

    Özçay, Figen; Barış, Zeren; Moray, Gökhan; Haberal, Nihan; Torgay, Adnan; Haberal, Mehmet

    2015-11-01

    Urea cycle defects are a group of metabolic disorders caused by enzymatic disruption of the urea cycle pathway, transforming nitrogen to urea for excretion from the body. Severe cases present in early infancy with life-threatening metabolic decompensation, and these episodes of hyperammonemia can be fatal or result in permanent neurologic damage. Despite the progress in pharmacologic treatment, long-term survival is poor especially for severe cases. Liver transplant is an alternative treatment option, providing sufficient enzymatic activity and decreasing the risk of metabolic decompensation. Three patients with urea cycle defects received related living-donor liver transplants at our hospital. Patients presented with late-onset ornithine transcarbamylase deficiency, argininosuccinate lyase deficiency, and citrullinemia. Maximum pretransplant ammonia levels were between 232 and 400 μmol/L (normal range is 18-72 μmol/L), and maximum posttransplant values were 52 to 94 μmol/L. All patients stopped medical treatment and dietary protein restriction for urea cycle defects after transplant. The patient with late-onset ornithine transcarbamylase deficiency already had motor deficits related to recurrent hyperammonemia attacks pretransplant. A major improvement could not be achieved, and he is wheelchair dependent at the age of 6 years. The other 2 patients had normal motor and mental skills before transplant, which have continued 12 and 14 months after transplant. Hepatic artery thrombosis in the patient with the ornithine transcarbamylase deficiency, intraabdominal infection in the patient with argininosuccinate lyase deficiency, and posterior reversible encephalopathy syndrome in the patient with citrullinemia were early postoperative complications. Histopathologic changes in livers explanted from patients with ornithine transcarbamylase deficiency and citrullinemia were nonspecific. The argininosuccinate lyase-deficient patient had portoportal fibrosis and cirrhotic

  4. Complex partial seizures: cerebellar metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Theodore, W.H.; Fishbein, D.; Deitz, M.; Baldwin, P.

    1987-07-01

    We used positron emission tomography (PET) with (/sup 18/F)2-deoxyglucose to study cerebellar glucose metabolism (LCMRglu) and the effect of phenytoin (PHT) in 42 patients with complex partial seizures (CPS), and 12 normal controls. Mean +/- SD patient LCMRglu was 6.9 +/- 1.8 mg glucose/100 g/min (left = right), significantly lower than control values of 8.5 +/- 1.8 (left, p less than 0.006), and 8.3 +/- 1.6 (right, p less than 0.02). Only four patients had cerebellar atrophy on CT/MRI; cerebellar LCMRglu in these was 5.5 +/- 1.5 (p = 0.054 vs. total patient sample). Patients with unilateral temporal hypometabolism or EEG foci did not have lateralized cerebellar hypometabolism. Patients receiving phenytoin (PHT) at the time of scan and patients with less than 5 years total PHT exposure had lower LCMRglu, but the differences were not significant. There were weak inverse correlations between PHT level and cerebellar LCMRglu in patients receiving PHT (r = -0.36; 0.05 less than p less than 0.1), as well as between length of illness and LCMRglu (r = -0.22; 0.05 less than p less than 0.1). Patients with complex partial seizures have cerebellar hypometabolism that is bilateral and due only in part to the effect of PHT.

  5. [Removable partial dentures. Oral functions and types].

    Science.gov (United States)

    Creugers, N H J; de Baat, C

    2009-11-01

    A removable partial denture enables the restoration or improvement of 4 oral functions: aesthetics, mandibular stability, mastication, and speech. However, wearing a removable partial denture should not cause oral comfort to deteriorate. There are 3 types of removable partial dentures: acrylic tissue-supported dentures, dentures with cast metal frameworks en dentures with cast metal frameworks and (semi)precision attachments. Interrupted tooth arches,free-ending tooth arches, and a combination of interrupted as well as free-ending tooth arches can be restored using these dentures. Well-known disadvantages of removable partial dentures are problematic oral hygiene, negative influence on the remaining dentition and limited oral comfort. Due to the advanced possibilities of fixed tooth- or implant-supported partial dentures, whether or not free-ending, or tooth- as well as implant-supported partial dentures, the indication of removable partial dentures is restricted. Nevertheless, for the time being the demand for removable partial dentures is expected to continue.

  6. Abstract methods in partial differential equations

    CERN Document Server

    Carroll, Robert W

    2012-01-01

    Detailed, self-contained treatment examines modern abstract methods in partial differential equations, especially abstract evolution equations. Suitable for graduate students with some previous exposure to classical partial differential equations. 1969 edition.

  7. Male patients with partial androgen insensitivity syndrome

    DEFF Research Database (Denmark)

    Hellmann, Philip; Christiansen, Peter; Johannsen, Trine Holm

    2012-01-01

    To describe the natural history of phenotype, growth and gonadal function in patients with partial androgen insensitivity syndrome.......To describe the natural history of phenotype, growth and gonadal function in patients with partial androgen insensitivity syndrome....

  8. PARALLEL SOLUTION METHODS OF PARTIAL DIFFERENTIAL EQUATIONS

    Directory of Open Access Journals (Sweden)

    Korhan KARABULUT

    1998-03-01

    Full Text Available Partial differential equations arise in almost all fields of science and engineering. Computer time spent in solving partial differential equations is much more than that of in any other problem class. For this reason, partial differential equations are suitable to be solved on parallel computers that offer great computation power. In this study, parallel solution to partial differential equations with Jacobi, Gauss-Siedel, SOR (Succesive OverRelaxation and SSOR (Symmetric SOR algorithms is studied.

  9. [Removable partial dentures. Oral functions and types

    NARCIS (Netherlands)

    Creugers, N.H.J.; Baat, C. de

    2009-01-01

    A removable partial denture enables the restoration or improvement of 4 oral functions: aesthetics, mandibular stability, mastication, and speech. However, wearing a removable partial denture should not cause oral comfort to deteriorate. There are 3 types of removable partial dentures: acrylic

  10. [Conventional retaining of removable partial dentures

    NARCIS (Netherlands)

    Keltjens, H.M.A.M.; Witter, D.J.; Creugers, N.H.J.

    2009-01-01

    Mechanical and biological criteria have to be met in retaining the metal frame of a removable partial denture. Additionally, a removable partial denture is part of the occlusal interface by the clasps and the denture teeth. With respect to mechanical aspects, all rigid parts of the removable partial

  11. Fatal coma in a young adult due to late-onset urea cycle deficiency presenting with a prolonged seizure: a case report.

    Science.gov (United States)

    Alameri, Majid; Shakra, Mustafa; Alsaadi, Taoufik

    2015-11-23

    Unexplained hyperammonemic coma in adults can be a medical dilemma in the absence of triggering factors and known comorbidities. Ornithine transcarbamylase deficiency presents most commonly with hyperammonemic coma. Although a rare disorder, ornithine transcarbamylase deficiency is the most common of the urea cycle disorders, which can occur both in children, and less commonly, in adults. The urea cycle disorder is usually acquired as an X-linked trait, and very rarely, similar to our reported case, may be acquired as a "new" mutation. Mutations that lead to later-onset presentations may lead to life-threatening disease and may be unrecognized, particularly when the first clinical symptoms occur in adulthood. We report the case of a previously healthy 17-year-old white man who developed a prolonged seizure and a rapid decline in mental status leading to coma over a 3-day period. Analysis of the OTC gene showed a 119G variant, which was identified in exon 2 of the OTC gene by sequencing. A diagnosis of ornithine transcarbamylase deficiency should be considered in adult patients who present with unexplained hyperammonemic coma and for all adult patients presenting with cryptogenic new-onset seizure and laboratory finding of elevated blood ammonia levels. This reported case highlights the importance of early recognition of this potentially reversible cause of life-threatening encephalopathy, as timely recognition and appropriate treatment can be lifesaving.

  12. Precipitation in partially stabilized zirconia

    International Nuclear Information System (INIS)

    Bansal, G.K.

    1975-01-01

    Transmission electron microscopy was used to study the substructure of partially stabilized ZrO 2 (PSZ) samples, i.e., 2-phase systems containing both cubic and monoclinic modifications of zirconia, after various heat treatments. Monoclinic ZrO 2 exists as (1) isolated grains within the polycrystalline aggregate (a grain- boundary phase) and (2) small plate-like particles within cubic grains. These intragranular precipitates are believed to contribute to the useful properties of PSZ via a form of precipitation hardening. These precipitates initially form as tetragonal ZrO 2 , with a habit plane parallel to the brace 100 brace matrix planes. The orientation relations between the tetragonal precipitates and the cubic matrix are brace 100 brace/sub matrix/ 2 parallel brace 100 brace /sub precipitate/ or (001)/sub precipitate/ and broken bracket 100 broken bracket/sub matrix/ 2 parallel broken bracket 100 broken bracket/sub precipitate/ or [001]/sub precipitate/. (U.S.)

  13. Partially coherent isodiffracting pulsed beams

    Science.gov (United States)

    Koivurova, Matias; Ding, Chaoliang; Turunen, Jari; Pan, Liuzhan

    2018-02-01

    We investigate a class of isodiffracting pulsed beams, which are superpositions of transverse modes supported by spherical-mirror laser resonators. By employing modal weights that, for stationary light, produce a Gaussian Schell-model beam, we extend this standard model to pulsed beams. We first construct the two-frequency cross-spectral density function that characterizes the spatial coherence in the space-frequency domain. By assuming a power-exponential spectral profile, we then employ the generalized Wiener-Khintchine theorem for nonstationary light to derive the two-time mutual coherence function that describes the space-time coherence of the ensuing beams. The isodiffracting nature of the laser resonator modes permits all (paraxial-domain) calculations at any propagation distance to be performed analytically. Significant spatiotemporal coupling is revealed in subcycle, single-cycle, and few-cycle domains, where the partial spatial coherence also leads to reduced temporal coherence even though full spectral coherence is assumed.

  14. Partial dynamical systems, fell bundles and applications

    CERN Document Server

    Exel, Ruy

    2017-01-01

    Partial dynamical systems, originally developed as a tool to study algebras of operators in Hilbert spaces, has recently become an important branch of algebra. Its most powerful results allow for understanding structural properties of algebras, both in the purely algebraic and in the C*-contexts, in terms of the dynamical properties of certain systems which are often hiding behind algebraic structures. The first indication that the study of an algebra using partial dynamical systems may be helpful is the presence of a grading. While the usual theory of graded algebras often requires gradings to be saturated, the theory of partial dynamical systems is especially well suited to treat nonsaturated graded algebras which are in fact the source of the notion of "partiality". One of the main results of the book states that every graded algebra satisfying suitable conditions may be reconstructed from a partial dynamical system via a process called the partial crossed product. Running in parallel with partial dynamica...

  15. Increases in urea synthesis and the ornithine-urea cycle capacity in the giant African snail, Achatina fulica, during fasting or aestivation, or after the injection with ammonium chloride.

    Science.gov (United States)

    Hiong, Kum Chew; Loong, Ai May; Chew, Shit Fun; Ip, Yuen Kwong

    2005-12-01

    The objectives of this study are to determine whether a full complement of ornithine-urea cycle (OUC) enzymes is present in the hepatopancreas of the giant African snail Achatina fulica, and to investigate whether the rate of urea synthesis and the OUC capacity can be up-regulated during 23 days of fasting or aestivation, or 24 hr post-injection with NH(4)Cl (10 micromol g(-1) snail) into the foot muscle. A. fulica is ureotelic and a full complement of OUC enzymes, including carbamoyl phosphate synthetase III (CPS III), was detected from its hepatopancreas. There were significant increases in the excretion of NH(4)(+), NH(3) and urea in fasting A. fulica. Fasting had no significant effect on the tissue ammonia contents, but led to a progressive accumulation of urea, which was associated with an 18-fold increase in the rate of urea synthesis. Because fasting took place in the presence of water and because there was no change in water contents in the foot muscle and hepatopancreas, it can be concluded that the function of urea accumulation in fasting A. fulica was unrelated to water retention. Aestivation in arid conditions led to a non-progressive accumulation of urea in A. fulica. During the first 4 days and the last 3 days of the 23-day aestivation period, experimental snails exhibited significantly greater rates of urea synthesis compared with fasted snails. These increases were associated with significant increases in activities of various OUC enzymes, except CPS III, in the hepatopancreas. However, the overall urea accumulation in snails aestivated and snails fasted for 23 days were comparable. Therefore, the classical hypothesis that urea accumulation occurred to prevent water loss through evaporation during aestivation in terrestrial pulmonates may not be valid. Surprisingly, there were no accumulations of ammonia in the foot muscle and hepatopancreas of A. fulica 12 or 24 hr after NH(4)Cl was injected into the foot muscle. In contrast, the urea content in

  16. Urtica dioica inhibits cell growth and induces apoptosis by targeting Ornithine decarboxylase and Adenosine deaminase as key regulatory enzymes in adenosine and polyamines homeostasis in human breast cancer cell lines.

    Science.gov (United States)

    Fattahi, Sadegh; Ghadami, Elham; Asouri, Mohsen; Motevalizadeh Ardekanid, Ali; Akhavan-Niaki, Haleh

    2018-02-28

    Breast cancer is a heterogeneous and multifactorial disease with variable disease progression risk, and treatment response. Urtica dioica is a traditional herb used as an adjuvant therapeutic agent in cancer. In the present study, we have evaluated the effects of the aqueous extract of Urtica dioica on Adenosine deaminase (ADA) and Ornithine decarboxylase (ODC1) gene expression in MCF-7, MDA-MB-231, two breast cancer cell lines being estrogen receptor positive and estrogen receptor negative, respectively.  Cell lines were cultured in suitable media. After 24 h, different concentrations of the extract were added and after 72 h, ADA and ODC1 gene expression as well as BCL2 and BAX apoptotic genes were assessed by Taqman real time PCR assay. Cells viability was assessed by MTT assay, and apoptosis was also evaluated at cellular level. The intra and extracellular levels of ODC1 and ADA enzymes were evaluated by ELISA. Results showed differential expression of ADA and ODC1 genes in cancer cell lines. In MCF-7 cell line, the expression level of ADA was upregulated in a dose-dependent manner but its expression did not change in MDA-MB cell line. ODC1 expression was increased in both examined cell lines. Also, increased level of the apoptotic BAX/BCL-2 ratio was detected in MCF-7 cells. These results demonstrated that Urtica dioica induces apoptosis in breast cancer cells by influencing ODC1 and ADA genes expression, and estrogen receptors. The different responses observed with these cell lines could be due to the interaction of Urtica dioica as a phytoestrogen with the estrogen receptor.

  17. Partial differential equations of mathematical physics

    CERN Document Server

    Sobolev, S L

    1964-01-01

    Partial Differential Equations of Mathematical Physics emphasizes the study of second-order partial differential equations of mathematical physics, which is deemed as the foundation of investigations into waves, heat conduction, hydrodynamics, and other physical problems. The book discusses in detail a wide spectrum of topics related to partial differential equations, such as the theories of sets and of Lebesgue integration, integral equations, Green's function, and the proof of the Fourier method. Theoretical physicists, experimental physicists, mathematicians engaged in pure and applied math

  18. [Removable partial dentures. Oral functions and types

    OpenAIRE

    Creugers, N.H.J.; Baat, C. de

    2009-01-01

    A removable partial denture enables the restoration or improvement of 4 oral functions: aesthetics, mandibular stability, mastication, and speech. However, wearing a removable partial denture should not cause oral comfort to deteriorate. There are 3 types of removable partial dentures: acrylic tissue-supported dentures, dentures with cast metal frameworks en dentures with cast metal frameworks and (semi)precision attachments. Interrupted tooth arches,free-ending tooth arches, and a combinatio...

  19. Partial vaginismus : definition, symptoms and treatment

    OpenAIRE

    Engman, Maria

    2007-01-01

    Vaginismus is a sexual pain disorder, where spasm of musculature of the outer third of the vagina interferes with intercourse. Vaginismus exists in two forms: total vaginismus, where intercourse is impossible, and the more seldom described partial vaginismus, in which intercourse is possible but painful. The aim of the thesis was to develop a useful definition of partial vaginismus for both clinical and scientific purposes; to describe the prevalence of partial vaginismus among women with sup...

  20. Partial Evaluation of the Euclidian Algorithm

    DEFF Research Database (Denmark)

    Danvy, Olivier; Goldberg, Mayer

    1997-01-01

    -like behavior. Each of them presents a challenge for partial evaluation. The Euclidian algorithm is one of them, and in this article, we make it amenable to partial evaluation. We observe that the number of iterations in the Euclidian algorithm is bounded by a number that can be computed given either of the two...... arguments. We thus rephrase this algorithm using bounded recursion. The resulting program is better suited for automatic unfolding and thus for partial evaluation. Its specialization is efficient....

  1. Partial distance correlation with methods for dissimilarities

    OpenAIRE

    Székely, Gábor J.; Rizzo, Maria L.

    2014-01-01

    Distance covariance and distance correlation are scalar coefficients that characterize independence of random vectors in arbitrary dimension. Properties, extensions, and applications of distance correlation have been discussed in the recent literature, but the problem of defining the partial distance correlation has remained an open question of considerable interest. The problem of partial distance correlation is more complex than partial correlation partly because the squared distance covari...

  2. Partial discharges and bulk dielectric field enhancement

    DEFF Research Database (Denmark)

    McAllister, Iain Wilson; Johansson, Torben

    2000-01-01

    A consequence of partial discharge activity within a gaseous void is the production of a field enhancement in the solid dielectric in the proximity of the void. This situation arises due to the charge created by the partial discharges accumulating at the void wall. The influence of the spatial...

  3. Laparoscopic partial nephrectomy for endophytic hilar tumors

    DEFF Research Database (Denmark)

    Di Pierro, G B; Tartaglia, N; Aresu, L

    2014-01-01

    To analyze feasibility and outcomes of laparoscopic partial nephrectomy (LPN) for endophytic hilar tumors in low-intermediate (ASA I-II) risk patients.......To analyze feasibility and outcomes of laparoscopic partial nephrectomy (LPN) for endophytic hilar tumors in low-intermediate (ASA I-II) risk patients....

  4. Removable partial overdentures for the irradiated patient

    International Nuclear Information System (INIS)

    Rosenberg, S.W.

    1990-01-01

    Patients who have received radiotherapy to the head and neck area must avoid dental extractions and seek simplicity in treatment and home care follow-up. For partially edentulous patients, removable partial overdenture therapy can fulfill these goals while maintaining the high level of function and aesthetics desired by patients.11 references

  5. Coordinating choice in partial cooperative equilibrium

    NARCIS (Netherlands)

    Mallozzi, L.; Tijs, S.H.

    2009-01-01

    In this paper we consider symmetric aggregative games and investigate partial cooperation between a portion of the players that sign a cooperative agreement and the rest of the players. Existence results of partial cooperative equilibria are obtained when the players who do not sign the agreement

  6. Memoization in Type-Directed Partial Evaluation

    DEFF Research Database (Denmark)

    Balat, Vincent; Danvy, Olivier

    2002-01-01

    the functions and type-directed partial evaluation provides a convenient setting to obtain the normal form of their composition. However, off-the-shelf type-directed partial evaluation turns out to yield gigantic normal forms. We identify that this gigantism is due to redundancies, and that these redundancies...

  7. Mathematical Modelling of Intraretinal Oxygen Partial Pressure ...

    African Journals Online (AJOL)

    Purpose: The aim of our present work is to develop a simple steady state model for intraretinal oxygen partial pressure distribution and to investigate the effect of various model parameters on the partial pressure distribution under adapted conditions of light and darkness.. Method: A simple eight-layered mathematical model ...

  8. Zero ischemia laparoscopic partial thulium laser nephrectomy.

    LENUS (Irish Health Repository)

    Thomas, Arun Z

    2013-11-01

    Laser technology presents a promising alternative to achieve tumor excision and renal hemostasis with or without hilar occlusion, yet its use in partial nephrectomy has not been significantly evaluated. We prospectively evaluated the thulium:yttrium-aluminum-garnet laser in laparoscopic partial nephrectomy (LPN) in our institution over a 1-year period.

  9. Esthetic Rehabilitation with a Cast Partial Denture

    Directory of Open Access Journals (Sweden)

    Suraksha Shrestha

    2017-01-01

    Full Text Available Removable partial denture is a treatment option where fixed prosthesis is not indicated. Due to its esthetic problems in the anterior region various modifications have been designed for its fabrication. This article describes an esthetic alternative using a round rest distal depression clasp for maxillary anterior teeth abutment while restoring the missing teeth with a cast partial denture.

  10. Heat deposition on the partial limiter

    International Nuclear Information System (INIS)

    Itoh, Kimitaka; Itoh, Sanae-I; Nagasaki, Kazunobu.

    1990-01-01

    The effect of the partial limiter in the outermost magnetic surface of toroidal plasmas is studied. The power deposition on the partial limiter and its effect on the temperature profile are analysed. Interpretation in terms of the perpendicular heat conductivity is also discussed. (author)

  11. Partial purification and biochemical characterization of acid ...

    African Journals Online (AJOL)

    Mung bean (Vigna radiata) is one of the important crops of the North Eastern Region of India. In the present study, acid phosphatase enzyme was isolated and partially purified from germinated local mung bean seeds. The sequential partial purification process was performed using ammonium sulphate precipitation method.

  12. Partial Safety Factors for Rubble Mound Breakwaters

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Burcharth, H. F.; Christiani, E.

    1995-01-01

    On the basis of the failure modes formulated in the various subtasks calibration of partial safety factors are described in this paper. The partial safety factors can be used to design breakwaters under quite different design conditions, namely probabilities of failure from 0.01 to 0.4, design...... lifetimes from 20 to 100 years and different qualities of wave data. A code of practice where safety is taken into account using partial safety factors is called a level I code. The partial safety factors are calibrated using First Order Reliability Methods (FORM, see Madsen et al. [1]) where...... in section 3. First Order Reliability Methods are described in section 4, and in section 5 it is shown how partial safety factors can be introduced and calibrated. The format of a code for design and analysis of rubble mound breakwaters is discussed in section 6. The mathematical formulation of the limit...

  13. Development of Partial Discharging Simulation Test Equipment

    Science.gov (United States)

    Kai, Xue; Genghua, Liu; Yan, Jia; Ziqi, Chai; Jian, Lu

    2017-12-01

    In the case of partial discharge training for recruits who lack of on-site work experience, the risk of physical shock and damage of the test equipment may be due to the limited skill level and improper operation by new recruits. Partial discharge simulation tester is the use of simulation technology to achieve partial discharge test process simulation, relatively true reproduction of the local discharge process and results, so that the operator in the classroom will be able to get familiar with and understand the use of the test process and equipment.The teacher sets up the instrument to display different partial discharge waveforms so that the trainees can analyze the test results of different partial discharge types.

  14. Comprehensive analysis of pyrimidine metabolism in 450 children with unspecific neurological symptoms using high-pressure liquid chromatography-electrospray ionization tandem mass spectrometry.

    Science.gov (United States)

    Schmidt, C; Hofmann, U; Kohlmüller, D; Mürdter, T; Zanger, U M; Schwab, M; Hoffmann, G F

    2005-01-01

    To evaluate the significance of inborn metabolic disorders of the pyrimidine degradation pathway, 450 children with unspecific neurological symptoms were comprehensively studied; 200 healthy children were recruited as controls. Uracil and thymine as well as their degradation products in urine were determined with an improved method based on reversed-phase HPLC coupled with electrospray ionization tandem mass spectrometry and detection by multiple-reaction monitoring using stable-isotope-labelled reference compounds as internal standards. From the results of the control group we established age-related reference ranges of all pyrimidine degradation products. In the patient group, two children with dihydropyrimidine dehydrogenase (DPYD) deficiency were identified; one of these was homozygous for the exon 14-skipping mutation of the DPYD gene. In addition, two patients with high uracil, dihydrouracil and beta-ureidopropionate were found to have ornithine transcarbamylase deficiency. In the urine of 9 patients, beta-alanine was markedly elevated owing to treatment with vigabatrin, an irreversible inhibitor of GABA transaminase, which interferes with beta-alanine breakdown. Four patients had exclusively high levels of beta-aminoisobutyrate (beta-AIB) due to a low activity of the D-beta-AIB-pyruvate aminotransferase, probably without clinical significance. In conclusion, quantitative investigation of pyrimidine metabolites in children with unexplained neurological symptoms, particularly epileptic seizures with or without psychomotor retardation, can be recommended as a helpful tool for diagnosis in clinical practice. Sensitive methods and age-related reference ranges enable the detection of partial enzyme deficiencies.

  15. Comparison of ultraviolet light-induced skin carcinogenesis and ornithine decarboxylase activity in sencar and hairless SKH-1 mice fed a constant level of dietary lipid varying in corn and coconut oil

    International Nuclear Information System (INIS)

    Berton, T.R.; Fischer, S.M.; Conti, C.J.; Locniskar, M.F.

    1996-01-01

    To investigate the effect of various levels of corn oil and coconut oil on ultraviolet (UV) light‐induced skin tumorigenesis and ornithine decarboxylase (ODC) activity, Sencar and SKH‐1 mice were fed one of three 15% (weight) fat semipurified diets containing three ratios of com oil to coconut oil: 1.0%:14.0%, 7.9%:7.1%, and 15.0%:0.0% in Diets A, B, and C, respectively. Groups of 30 Sencar and SKH‐1 mice were fed one of the diets for three weeks before UV irradiation; then both strains were UV irradiated with an initial dose of 90 mJ/cm2. The dose was given three times a week and increased 25% each week. For Sencar mice (irradiated 33 wks for a total dose of 48 J/cm2), tumor incidence reached a maximum of 60%, 60%, and 53% for Diets A, B, and C, respectively, with an overall average of one to two tumors per tumor‐bearing animal. For the SKH‐1 mice (irradiated 29 wks for a total dose of 18 J/cm2), all diet groups reached 100% incidence by 29 weeks, with approximately 12 tumors per tumor‐bearing mouse. No significant effect of dietary corn oil/coconut oil was found for tumor latency, incidence, or yield in either strain. The effect of increasing com oil on epidermal ODC activity in chronically UV‐irradiated Sencar and SKH‐1 mice was assessed Three groups of mice from each strain were fed one of the experimental diets and UV irradiated for six weeks. Sencar mice showed no increase in ODC activity until six weeks of treatment, when the levels of ODC activity in the UV‐irradiated mice fed Diet A were significantly higher than those in mice fed Diet B or Diet C: 1.27, 0.55, and 0.52 nmol/mg protein/hr, respectively. In the SKH‐1 mice, ODC activity was increased by the first week of UV treatment, and by three weeks of treatment a dietary effect was observed: ODC activity was significantly higher in mice fed Diet C (0.70 nmol/mg protein/hr) than in mice fed Diet A (0.18 nmol/mg protein/hr). Although there was no significant effect of dietary corn oil

  16. Partially Observed Mixtures of IRT Models: An Extension of the Generalized Partial-Credit Model

    Science.gov (United States)

    Von Davier, Matthias; Yamamoto, Kentaro

    2004-01-01

    The generalized partial-credit model (GPCM) is used frequently in educational testing and in large-scale assessments for analyzing polytomous data. Special cases of the generalized partial-credit model are the partial-credit model--or Rasch model for ordinal data--and the two parameter logistic (2PL) model. This article extends the GPCM to the…

  17. Partial transposition on bi-partite system

    OpenAIRE

    Han, Y. -J.; Ren, X. J.; Wu, Y. C.; Guo, G. -C.

    2006-01-01

    Many of the properties of the partial transposition are not clear so far. Here the number of the negative eigenvalues of K(T)(the partial transposition of K) is considered carefully when K is a two-partite state. There are strong evidences to show that the number of negative eigenvalues of K(T) is N(N-1)/2 at most when K is a state in Hilbert space N*N. For the special case, 2*2 system(two qubits), we use this result to give a partial proof of the conjecture sqrt(K(T))(T)>=0. We find that thi...

  18. Numerical Analysis of Partial Differential Equations

    CERN Document Server

    Lui, S H

    2011-01-01

    A balanced guide to the essential techniques for solving elliptic partial differential equations Numerical Analysis of Partial Differential Equations provides a comprehensive, self-contained treatment of the quantitative methods used to solve elliptic partial differential equations (PDEs), with a focus on the efficiency as well as the error of the presented methods. The author utilizes coverage of theoretical PDEs, along with the nu merical solution of linear systems and various examples and exercises, to supply readers with an introduction to the essential concepts in the numerical analysis

  19. Partial differential equations for scientists and engineers

    CERN Document Server

    Farlow, Stanley J

    1993-01-01

    Most physical phenomena, whether in the domain of fluid dynamics, electricity, magnetism, mechanics, optics, or heat flow, can be described in general by partial differential equations. Indeed, such equations are crucial to mathematical physics. Although simplifications can be made that reduce these equations to ordinary differential equations, nevertheless the complete description of physical systems resides in the general area of partial differential equations.This highly useful text shows the reader how to formulate a partial differential equation from the physical problem (constructing th

  20. Partial Deconvolution with Inaccurate Blur Kernel.

    Science.gov (United States)

    Ren, Dongwei; Zuo, Wangmeng; Zhang, David; Xu, Jun; Zhang, Lei

    2017-10-17

    Most non-blind deconvolution methods are developed under the error-free kernel assumption, and are not robust to inaccurate blur kernel. Unfortunately, despite the great progress in blind deconvolution, estimation error remains inevitable during blur kernel estimation. Consequently, severe artifacts such as ringing effects and distortions are likely to be introduced in the non-blind deconvolution stage. In this paper, we tackle this issue by suggesting: (i) a partial map in the Fourier domain for modeling kernel estimation error, and (ii) a partial deconvolution model for robust deblurring with inaccurate blur kernel. The partial map is constructed by detecting the reliable Fourier entries of estimated blur kernel. And partial deconvolution is applied to wavelet-based and learning-based models to suppress the adverse effect of kernel estimation error. Furthermore, an E-M algorithm is developed for estimating the partial map and recovering the latent sharp image alternatively. Experimental results show that our partial deconvolution model is effective in relieving artifacts caused by inaccurate blur kernel, and can achieve favorable deblurring quality on synthetic and real blurry images.Most non-blind deconvolution methods are developed under the error-free kernel assumption, and are not robust to inaccurate blur kernel. Unfortunately, despite the great progress in blind deconvolution, estimation error remains inevitable during blur kernel estimation. Consequently, severe artifacts such as ringing effects and distortions are likely to be introduced in the non-blind deconvolution stage. In this paper, we tackle this issue by suggesting: (i) a partial map in the Fourier domain for modeling kernel estimation error, and (ii) a partial deconvolution model for robust deblurring with inaccurate blur kernel. The partial map is constructed by detecting the reliable Fourier entries of estimated blur kernel. And partial deconvolution is applied to wavelet-based and learning

  1. PARTIAL REINFORCEMENT (ACQUISITION) EFFECTS WITHIN SUBJECTS.

    Science.gov (United States)

    AMSEL, A; MACKINNON, J R; RASHOTTE, M E; SURRIDGE, C T

    1964-03-01

    Acquisition performance of 22 rats in a straight alley runway was examined. The animals were subjected to partial reinforcement when the alley was black (B+/-) and continuous reinforcement when it was white (W+). The results indicated (a) higher terminal performance, for partial as against continuous reinforcement conditions, for starting-time and running-time measures, and (b) lower terminal performance under partial conditions for a goal-entry-time measure. These results confirm within subjects an effect previously demonstrated, in the runway, only in between-groups tests, where one group is run under partial reinforcement and a separate group is run under continuous reinforcement in the presence of the same external stimuli. Differences between the runway situation, employing a discrete-trial procedure and performance measures at three points in the response chain, and the Skinner box situation, used in its free-operant mode with a single performance measure, are discussed in relation to the present findings.

  2. Introduction to partial differential equations with applications

    CERN Document Server

    Zachmanoglou, E C

    1988-01-01

    This text explores the essentials of partial differential equations as applied to engineering and the physical sciences. Discusses ordinary differential equations, integral curves and surfaces of vector fields, the Cauchy-Kovalevsky theory, more. Problems and answers.

  3. Dual Component Removable Partial Denture shows improved ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-02-18

    Feb 18, 2009 ... 2Faculty of Dentistry, the University of Hong Kong, Hong Kong. 3Department of ... an example of poor oral condition caused mainly by periodontitis, and ... working model of the Dual Component Removable Partial Denture.

  4. Evaluation of Prothrombin Time and Activated Partial ...

    African Journals Online (AJOL)

    and activated partial thromboplastin time (APTT) were investigated in treated and untreated diabetics as well as ... decrease the availability of these proteins which affect the clotting ... calcum rabbit brain thromboplastin reagent placed in.

  5. chemical composition and sensory acceptability of partially ...

    African Journals Online (AJOL)

    Pasta products were produced from partially gelatinized blends of wheat, ... products were significantly different in height, thickness and expansion ratio but, not significantly different ... protein and no less than 30% of wet gluten (protein.

  6. Hospital Outpatient PPS Partial Hospitalization Program LDS

    Data.gov (United States)

    U.S. Department of Health & Human Services — Hospital Outpatient Prospective Payment System (OPPS) Partial Hospitalization Program LDS This file contains select claim level data and is derived from 2010 claims...

  7. On construction of partial association rules

    KAUST Repository

    Moshkov, Mikhail; Piliszczuk, Marcin; Zielosko, Beata Marta

    2009-01-01

    This paper is devoted to the study of approximate algorithms for minimization of partial association rule length. It is shown that under some natural assumptions on the class NP, a greedy algorithm is close to the best polynomial approximate

  8. Partial Duplication of Chromosome 8p

    African Journals Online (AJOL)

    rme

    The partial chromosome 8p duplication is a rare syndrome and is ... abnormality of maternal origin that ... second trimester by vaginal bleeding and ... echocardiography, brain CT scan and. MRI. Fig. 1:Conventional karyotype of case 3 showing.

  9. Clustering stocks using partial correlation coefficients

    Science.gov (United States)

    Jung, Sean S.; Chang, Woojin

    2016-11-01

    A partial correlation analysis is performed on the Korean stock market (KOSPI). The difference between Pearson correlation and the partial correlation is analyzed and it is found that when conditioned on the market return, Pearson correlation coefficients are generally greater than those of the partial correlation, which implies that the market return tends to drive up the correlation between stock returns. A clustering analysis is then performed to study the market structure given by the partial correlation analysis and the members of the clusters are compared with the Global Industry Classification Standard (GICS). The initial hypothesis is that the firms in the same GICS sector are clustered together since they are in a similar business and environment. However, the result is inconsistent with the hypothesis and most clusters are a mix of multiple sectors suggesting that the traditional approach of using sectors to determine the proximity between stocks may not be sufficient enough to diversify a portfolio.

  10. Partial Actions, Paradoxicality and Topological full Groups

    DEFF Research Database (Denmark)

    Scarparo, Eduardo

    uniform Roe algebra is finite. In Article C, we analyze the C*-algebra generated by the Koopman representation of a topological full group, showing, in particular, that it is not AF andhas real rank zero. We also prove that if G is a finitely generated, elementary amenable group, and C*(G) has real rank......We study how paradoxicality properties affect the way groups partially acton topological spaces and C*-algebras. We also investigate the real rank zero and AF properties for certain classes of group C*-algebras. Specifically, in article A, we characterize supramenable groups in terms of existence...... of invariant probability measures for partial actions on compact Hausdorff spaces and existence of tracial states on partial crossed products. These characterizations show that, in general, one cannot decompose a partial crossed product of a C*-algebra by a semidirect product of groups as two iterated...

  11. Higher-order rewriting and partial evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier; Rose, Kristoffer H.

    1998-01-01

    We demonstrate the usefulness of higher-order rewriting techniques for specializing programs, i.e., for partial evaluation. More precisely, we demonstrate how casting program specializers as combinatory reduction systems (CRSs) makes it possible to formalize the corresponding program...

  12. Mathematical Modelling of Intraretinal Oxygen Partial Pressure

    African Journals Online (AJOL)

    Erah

    oxygen availability) is required for retinal oxidative metabolism. .... retina was described using Hill's equation and Fick's law. ... ganglion cell / nerve fiber layer and the superficial ..... parameter values producing the best. Figure 2: Partial ...

  13. Partial Differential Equations Modeling and Numerical Simulation

    CERN Document Server

    Glowinski, Roland

    2008-01-01

    This book is dedicated to Olivier Pironneau. For more than 250 years partial differential equations have been clearly the most important tool available to mankind in order to understand a large variety of phenomena, natural at first and then those originating from human activity and technological development. Mechanics, physics and their engineering applications were the first to benefit from the impact of partial differential equations on modeling and design, but a little less than a century ago the Schrödinger equation was the key opening the door to the application of partial differential equations to quantum chemistry, for small atomic and molecular systems at first, but then for systems of fast growing complexity. Mathematical modeling methods based on partial differential equations form an important part of contemporary science and are widely used in engineering and scientific applications. In this book several experts in this field present their latest results and discuss trends in the numerical analy...

  14. Genetics Home Reference: ornithine translocase deficiency

    Science.gov (United States)

    ... belongs to a class of genetic diseases called urea cycle disorders. The urea cycle is a sequence of reactions ... First Test GeneReview: Hyperornithinemia-Hyperammonemia-Homocitrullinuria ... Encyclopedia: Hereditary urea cycle abnormality National ...

  15. Partial discharge transients: The field theoretical approach

    DEFF Research Database (Denmark)

    McAllister, Iain Wilson; Crichton, George C

    1998-01-01

    Up until the mid-1980s the theory of partial discharge transients was essentially static. This situation had arisen because of the fixation with the concept of void capacitance and the use of circuit theory to address what is in essence a field problem. Pedersen rejected this approach and instead...... began to apply field theory to the problem of partial discharge transients. In the present paper, the contributions of Pedersen using the field theoretical approach will be reviewed and discussed....

  16. A Model for Partial Kantian Cooperation

    OpenAIRE

    Kordonis, Ioannis

    2016-01-01

    This work presents a game theoretic model to describe game situations in which there is a partial cooperation among the players. Specifically, we assume that the players partially follow Kant's "Categorical Imperative". The model is stated for games with a continuum of players and the basic assumption made is that the participants consider that they belong to virtual groups in which they optimize their actions as if they were bound to follow the same strategy. The relation with the Nash, (Ben...

  17. On the Partiality of Procreative Beneficence

    DEFF Research Database (Denmark)

    Petersen, Thomas Søbirk

    2015-01-01

    The aim of this paper is to criticise the well-discussed principle of Procreative Beneficence (PB) lately refined by Julian Savulescu and Guy Kahane. First, it is argued that advocates of PB leave us with an implausible justification for the moral partiality towards the child (or children) which...... the target. Finally, a genuine counterexample to PB is developed in order to show that the partiality of PB leads to the wrong answer in a specific case....

  18. Pancharatnam geometric phase originating from successive partial ...

    Indian Academy of Sciences (India)

    Pancharatnam connection [1,2] dictates that ψp is in phase ψ0. The partial projection effects a ... up to a real multiplier. Here again, ψf is in phase with ψp but relative to ψ0, has a .... For the third partial projection of strength t3 and an azimuth angle φ13 to effect a triangle closure for both initial states |z〉 and | − z〉, we derive ...

  19. Spreading paths in partially observed social networks

    Science.gov (United States)

    Onnela, Jukka-Pekka; Christakis, Nicholas A.

    2012-03-01

    Understanding how and how far information, behaviors, or pathogens spread in social networks is an important problem, having implications for both predicting the size of epidemics, as well as for planning effective interventions. There are, however, two main challenges for inferring spreading paths in real-world networks. One is the practical difficulty of observing a dynamic process on a network, and the other is the typical constraint of only partially observing a network. Using static, structurally realistic social networks as platforms for simulations, we juxtapose three distinct paths: (1) the stochastic path taken by a simulated spreading process from source to target; (2) the topologically shortest path in the fully observed network, and hence the single most likely stochastic path, between the two nodes; and (3) the topologically shortest path in a partially observed network. In a sampled network, how closely does the partially observed shortest path (3) emulate the unobserved spreading path (1)? Although partial observation inflates the length of the shortest path, the stochastic nature of the spreading process also frequently derails the dynamic path from the shortest path. We find that the partially observed shortest path does not necessarily give an inflated estimate of the length of the process path; in fact, partial observation may, counterintuitively, make the path seem shorter than it actually is.

  20. Spreading paths in partially observed social networks.

    Science.gov (United States)

    Onnela, Jukka-Pekka; Christakis, Nicholas A

    2012-03-01

    Understanding how and how far information, behaviors, or pathogens spread in social networks is an important problem, having implications for both predicting the size of epidemics, as well as for planning effective interventions. There are, however, two main challenges for inferring spreading paths in real-world networks. One is the practical difficulty of observing a dynamic process on a network, and the other is the typical constraint of only partially observing a network. Using static, structurally realistic social networks as platforms for simulations, we juxtapose three distinct paths: (1) the stochastic path taken by a simulated spreading process from source to target; (2) the topologically shortest path in the fully observed network, and hence the single most likely stochastic path, between the two nodes; and (3) the topologically shortest path in a partially observed network. In a sampled network, how closely does the partially observed shortest path (3) emulate the unobserved spreading path (1)? Although partial observation inflates the length of the shortest path, the stochastic nature of the spreading process also frequently derails the dynamic path from the shortest path. We find that the partially observed shortest path does not necessarily give an inflated estimate of the length of the process path; in fact, partial observation may, counterintuitively, make the path seem shorter than it actually is.

  1. Compatriot partiality and cosmopolitan justice: Can we justify compatriot partiality within the cosmopolitan framework?

    Directory of Open Access Journals (Sweden)

    Rachelle Bascara

    2016-10-01

    Full Text Available This paper shows an alternative way in which compatriot partiality could be justified within the framework of global distributive justice. Philosophers who argue that compatriot partiality is similar to racial partiality capture something correct about compatriot partiality. However, the analogy should not lead us to comprehensively reject compatriot partiality. We can justify compatriot partiality on the same grounds that liberation movements and affirmative action have been justified. Hence, given cosmopolitan demands of justice, special consideration for the economic well-being of your nation as a whole is justified if and only if the country it identifies is an oppressed developing nation in an unjust global order.This justification is incomplete. We also need to say why Person A, qua national of Country A, is justified in helping her compatriots in Country A over similarly or slightly more oppressed non-compatriots in Country B. I argue that Person A’s partiality towards her compatriots admits further vindication because it is part of an oppressed group’s project of self-emancipation, which is preferable to paternalistic emancipation.Finally, I identify three benefits in my justification for compatriot partiality. First, I do not offer a blanket justification for all forms of compatriot partiality. Partiality between members of oppressed groups is only a temporary effective measure designed to level an unlevel playing field. Second, because history attests that sovereign republics could arise as a collective response to colonial oppression, justifying compatriot partiality on the grounds that I have identified is conducive to the development of sovereignty and even democracy in poor countries, thereby avoiding problems of infringement that many humanitarian poverty alleviation efforts encounter. Finally, my justification for compatriot partiality complies with the implicit cosmopolitan commitment to the realizability of global justice

  2. Effect of short-term ornithine alpha-ketoglutarate pretreatment on intestinal ischemia-reperfusion in rats Efeitos do pré-tratamento em curto prazo com ornitina alfa-cetoglutarato na isquemia-reperfusão intestinal em ratos

    Directory of Open Access Journals (Sweden)

    Eduardo Silvio Gouveia Gonçalves

    2011-01-01

    Full Text Available PURPOSE: To investigate the effects of preventive enteral administration of ornithine alpha-ketoglutarate (OKG in an ischemia-reperfusion rat model. METHODS: Sixty rats were randomized into five groups (G1-G5, n = 12. Each group was divided into two subgroups (n = 6 and treated with calcium carbonate (CaCa or OKG by gavage. Thirty minutes later, the animals were anesthetized with xylazine 15mg + ketamine 1mg ip and subjected to laparotomy. G1-G3 rats served as controls. Rats in groups G4 and G5 were subjected to ischemia for 30 minutes. Ischemia was achieved by clamping the small intestine and its mesentery, delimiting a segment of bowel 5 cm long and 5 cm apart from the ileocecal valve. In addition, G5 rats underwent reperfusion for 30 minutes. Blood samples were collected at the end of the laparotomy (G1, after 30 minutes (G2, G4 and 60 minutes (G3, G5 to determine concentrations of metabolites (pyruvate, lactate, creatine phosphokinase (CPK, thiobarbituric acid reactive substances (TBARS and glutathione (GSH. RESULTS: There was a significant decrease in tissue pyruvate and lactate and plasma CPK levels in OKG-treated rats at the end of reperfusion period. GSH levels did not change significantly in ischemia and reperfusion groups. However, TBARS levels increased significantly (pOBJETIVO: Investigar os efeitos da administração enteral preventiva de ornitina alfa-cetoglutarato (OKG em modelo de isquemia-reperfusão no rato. MÉTODOS: Sessenta ratos foram randomizados em cinco grupos (G1-G5, n=12. Cada grupo foi redistribuído em dois subgrupos (n=6 e tratado com carbonato de cálcio (CaCa ou OKG por gavagem. Trinta minutos mais tarde, os animais foram anestesiados com xilazina 1mg+cetamina 15mg i.p. e submetidos à laparotomia. Os ratos dos grupos G4-G5 foram submetidos à isquemia por 30 minutos. A isquemia foi obtida por pinçamento do intestino delgado, delimitando um segmento com 5 cm de comprimento e distando 5 cm da válvula ileocecal. O

  3. A novel technique for partial discharge measurement

    International Nuclear Information System (INIS)

    Farrokh, Fattahi; Navid, Tagizadegan; Ahmad, Zentabchi; Mehdi, Rashidi

    2005-01-01

    Full text : Partial discharges are a sensitive measure of local electrical stress and therefore the measurements is very often used as a quality check of the insulation. The inception of partial discharges gives information on the limit of the electrical strength of the insulating material before a complete discharge between the conductors takes place. Therefore the insulating material can be tested with high stress but without damaging or reducing the performance of the insulation. Also, for partial discharge measurements it should be taken into account that every stress of the insulation will have an influence on the life expectancy of the material, but a reasonable compromise between the stress during the measurement in order to get reliable results and the influence of he lifetime should be found and established in the relevant standard for the particular equipment, for example transformers, cables and so on

  4. Thin film oxygen partial pressure sensor

    Science.gov (United States)

    Wortman, J. J.; Harrison, J. W.; Honbarrier, H. L.; Yen, J.

    1972-01-01

    The development is described of a laboratory model oxygen partial pressure sensor using a sputtered zinc oxide thin film. The film is operated at about 400 C through the use of a miniature silicon bar. Because of the unique resistance versus temperature relation of the silicon bar, control of the operational temperature is achieved by controlling the resistance. A circuit for accomplishing this is described. The response of sputtered zinc oxide films of various thicknesses to oxygen, nitrogen, argon, carbon dioxide, and water vapor caused a change in the film resistance. Over a large range, film conductance varied approximately as the square root of the oxygen partial pressure. The presence of water vapor in the gas stream caused a shift in the film conductance at a given oxygen partial pressure. A theoretical model is presented to explain the characteristic features of the zinc oxide response to oxygen.

  5. Particle Systems and Partial Differential Equations I

    CERN Document Server

    Gonçalves, Patricia

    2014-01-01

    This book presents the proceedings of the international conference Particle Systems and Partial Differential Equations I, which took place at the Centre of Mathematics of the University of Minho, Braga, Portugal, from the 5th to the 7th of December, 2012.  The purpose of the conference was to bring together world leaders to discuss their topics of expertise and to present some of their latest research developments in those fields. Among the participants were researchers in probability, partial differential equations and kinetics theory. The aim of the meeting was to present to a varied public the subject of interacting particle systems, its motivation from the viewpoint of physics and its relation with partial differential equations or kinetics theory, and to stimulate discussions and possibly new collaborations among researchers with different backgrounds.  The book contains lecture notes written by François Golse on the derivation of hydrodynamic equations (compressible and incompressible Euler and Navie...

  6. Partial Thickness Rotator Cuff Tears: Current Concepts

    Science.gov (United States)

    Matthewson, Graeme; Beach, Cara J.; Nelson, Atiba A.; Woodmass, Jarret M.; Ono, Yohei; Boorman, Richard S.; Lo, Ian K. Y.; Thornton, Gail M.

    2015-01-01

    Partial thickness rotator cuff tears are a common cause of pain in the adult shoulder. Despite their high prevalence, the diagnosis and treatment of partial thickness rotator cuff tears remains controversial. While recent studies have helped to elucidate the anatomy and natural history of disease progression, the optimal treatment, both nonoperative and operative, is unclear. Although the advent of arthroscopy has improved the accuracy of the diagnosis of partial thickness rotator cuff tears, the number of surgical techniques used to repair these tears has also increased. While multiple repair techniques have been described, there is currently no significant clinical evidence supporting more complex surgical techniques over standard rotator cuff repair. Further research is required to determine the clinical indications for surgical and nonsurgical management, when formal rotator cuff repair is specifically indicated and when biologic adjunctive therapy may be utilized. PMID:26171251

  7. Partially massless graviton on beyond Einstein spacetimes

    Science.gov (United States)

    Bernard, Laura; Deffayet, Cédric; Hinterbichler, Kurt; von Strauss, Mikael

    2017-06-01

    We show that a partially massless graviton can propagate on a large set of spacetimes which are not Einstein spacetimes. Starting from a recently constructed theory for a massive graviton that propagates the correct number of degrees of freedom on an arbitrary spacetime, we first give the full explicit form of the scalar constraint responsible for the absence of a sixth degree of freedom. We then spell out generic conditions for the constraint to be identically satisfied, so that there is a scalar gauge symmetry which makes the graviton partially massless. These simplify if one assumes that spacetime is Ricci symmetric. Under this assumption, we find explicit non-Einstein spacetimes (some, but not all, with vanishing Bach tensors) allowing for the propagation of a partially massless graviton. These include in particular the Einstein static Universe.

  8. Partial Thickness Rotator Cuff Tears: Current Concepts

    Directory of Open Access Journals (Sweden)

    Graeme Matthewson

    2015-01-01

    Full Text Available Partial thickness rotator cuff tears are a common cause of pain in the adult shoulder. Despite their high prevalence, the diagnosis and treatment of partial thickness rotator cuff tears remains controversial. While recent studies have helped to elucidate the anatomy and natural history of disease progression, the optimal treatment, both nonoperative and operative, is unclear. Although the advent of arthroscopy has improved the accuracy of the diagnosis of partial thickness rotator cuff tears, the number of surgical techniques used to repair these tears has also increased. While multiple repair techniques have been described, there is currently no significant clinical evidence supporting more complex surgical techniques over standard rotator cuff repair. Further research is required to determine the clinical indications for surgical and nonsurgical management, when formal rotator cuff repair is specifically indicated and when biologic adjunctive therapy may be utilized.

  9. Partial Cavity Flows at High Reynolds Numbers

    Science.gov (United States)

    Makiharju, Simo; Elbing, Brian; Wiggins, Andrew; Dowling, David; Perlin, Marc; Ceccio, Steven

    2009-11-01

    Partial cavity flows created for friction drag reduction were examined on a large-scale. Partial cavities were investigated at Reynolds numbers up to 120 million, and stable cavities with frictional drag reduction of more than 95% were attained at optimal conditions. The model used was a 3 m wide and 12 m long flat plate with a plenum on the bottom. To create the partial cavity, air was injected at the base of an 18 cm backwards-facing step 2.1 m from the leading edge. The geometry at the cavity closure was varied for different flow speeds to optimize the closure of the cavity. Cavity gas flux, thickness, frictional loads, and cavity pressures were measured over a range of flow speeds and air injection fluxes. High-speed video was used extensively to investigate the unsteady three dimensional cavity closure, the overall cavity shape and oscillations.

  10. Partial discharges in ellipsoidal and spheroidal voids

    DEFF Research Database (Denmark)

    Crichton, George C; Karlsson, P. W.; Pedersen, Aage

    1989-01-01

    Transients associated with partial discharges in voids can be described in terms of the charges induced on the terminal electrodes of the system. The relationship between the induced charge and the properties which are usually measured is discussed. The method is illustrated by applying it to a s......Transients associated with partial discharges in voids can be described in terms of the charges induced on the terminal electrodes of the system. The relationship between the induced charge and the properties which are usually measured is discussed. The method is illustrated by applying...

  11. arXiv Minimal Fundamental Partial Compositeness

    CERN Document Server

    Cacciapaglia, Giacomo; Sannino, Francesco; Thomsen, Anders Eller

    Building upon the fundamental partial compositeness framework we provide consistent and complete composite extensions of the standard model. These are used to determine the effective operators emerging at the electroweak scale in terms of the standard model fields upon consistently integrating out the heavy composite dynamics. We exhibit the first effective field theories matching these complete composite theories of flavour and analyse their physical consequences for the third generation quarks. Relations with other approaches, ranging from effective analyses for partial compositeness to extra dimensions as well as purely fermionic extensions, are briefly discussed. Our methodology is applicable to any composite theory of dynamical electroweak symmetry breaking featuring a complete theory of flavour.

  12. Higher-Order Rewriting and Partial Evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier; Rose, Kristoffer H.

    1997-01-01

    transformations as meta-reductions, i.e., reductions in the internal “substitution calculus.” For partial-evaluation problems, this means that instead of having to prove on a case-by-case basis that one's “two-level functions” operate properly, one can concisely formalize them as a combinatory reduction system...... and obtain as a corollary that static reduction does not go wrong and yields a well-formed residual program. We have found that the CRS substitution calculus provides an adequate expressive power to formalize partial evaluation: it provides sufficient termination strength while avoiding the need...

  13. Flexible removable partial dentures: a basic overview.

    Science.gov (United States)

    Hill, Edward E; Rubel, Barry; Smith, John B

    2014-01-01

    For many years, flexible resin materials have been available for fabricating removable partial denture (RPD) prostheses. Using a nonrigid material for the major connector or other components of an RPD may be a consideration for certain patients. Except for the promotional literature that has been written for flexible resin dentures, there is very little information available in the dental literature concerning nonrigid RPDs. As a result, the decision to use this treatment option depends on the judgment and experience of the dentist and fabricating laboratory. This article summarizes clinically pertinent information about flexible, nonrigid partial dentures.

  14. DEVICE FOR CONTROL OF OXYGEN PARTIAL PRESSURE

    Science.gov (United States)

    Bradner, H.; Gordon, H.S.

    1957-12-24

    A device is described that can sense changes in oxygen partial pressure and cause a corresponding mechanical displacement sufficient to actuate meters, valves and similar devices. A piston and cylinder arrangement contains a charge of crystalline metal chelate pellets which have the peculiar property of responding to variations in the oxygen content of the ambient atmosphere by undergoing a change in dimension. A lever system amplifies the relative displacement of the piston in the cylinder, and actuates the controlled valving device. This partial pressure oxygen sensing device is useful in controlled chemical reactions or in respiratory devices such as the oxygen demand meters for high altitude aircraft.

  15. Partial gravity - Human impacts on facility design

    Science.gov (United States)

    Capps, Stephen; Moore, Nathan

    1990-01-01

    Partial gravity affects the body differently than earth gravity and microgravity environments. The main difference from earth gravity is human locomotion; while the main dfference from microgravity is the specific updown orientation and reach envelopes which increase volume requirements. Much data are available on earth gravity and microgravity design; however, very little information is available on human reactions to reduced gravity levels in IVA situations (without pressure suits). Therefore, if humans commit to permanent lunar habitation, much research should be conducted in the area of partial gravity effects on habitat design.

  16. Proximal Hamstring Tendinosis and Partial Ruptures.

    Science.gov (United States)

    Startzman, Ashley N; Fowler, Oliver; Carreira, Dominic

    2017-07-01

    Proximal hamstring tendinosis and partial hamstring origin ruptures are painful conditions of the proximal thigh and hip that may occur in the acute, chronic, or acute on chronic setting. Few publications exist related to their diagnosis and management. This systematic review discusses the incidence, treatment, and prognosis of proximal hamstring tendinosis and partial hamstring ruptures. Conservative treatment measures include nonsteroidal anti-inflammatory drugs, physical therapy, rest, and ice. If these measures fail, platelet-rich plasma or shockwave therapy may be considered. When refractory to conservative management, these injuries may be treated with surgical debridement and hamstring reattachment. [Orthopedics. 2017; 40(4):e574-e582.]. Copyright 2017, SLACK Incorporated.

  17. Partial oxidation of 2-propanol on perovskites

    Energy Technology Data Exchange (ETDEWEB)

    Sumathi, R.; Viswanathan, B.; Varadarajan, T.K. [Indian Inst. of Tech., Madras (India). Dept. of Chemistry

    1998-12-31

    Partial oxidation of 2-propanol was carried out on AB{sub 1-x}B`{sub x}O{sub 3} (A=Ba, B=Pb, Ce, Ti; B`=Bi, Sb and Cu) type perovskite oxides. Acetone was the major product observed on all the catalysts. All the catalysts underwent partial reduction during the reaction depending on the composition of the reactant, nature of the B site cation and the extent of substitution at B site. The catalytic activity has been correlated with the reducibility of the perovskite oxides determined from Temperature Programmed Reduction (TPR) studies. (orig.)

  18. Generalized solutions of nonlinear partial differential equations

    CERN Document Server

    Rosinger, EE

    1987-01-01

    During the last few years, several fairly systematic nonlinear theories of generalized solutions of rather arbitrary nonlinear partial differential equations have emerged. The aim of this volume is to offer the reader a sufficiently detailed introduction to two of these recent nonlinear theories which have so far contributed most to the study of generalized solutions of nonlinear partial differential equations, bringing the reader to the level of ongoing research.The essence of the two nonlinear theories presented in this volume is the observation that much of the mathematics concernin

  19. Barrelet zeros in partial wave analysis

    International Nuclear Information System (INIS)

    Baker, R.D.

    1976-01-01

    The formalism of Barrelet zeros is discussed. Spinless scattering is described to introduce the idea, then the more usual case of 0 - 1/2 + → 0 - 1/2 + scattering. The zeros are regarded here only as a means to an end, viz the partial waves. The extraction of these is given in detail, and ambiguities are discussed at length. (author)

  20. Partial discharges in spheroidal voids: Void orientation

    DEFF Research Database (Denmark)

    McAllister, Iain Wilson

    1997-01-01

    Partial discharge transients can be described in terms of the charge induced on the detecting electrode. The influence of the void parameters upon the induced charge is examined and discussed for spheroidal voids. It is shown that a quantitative interpretation of the induced charge requires...

  1. Partial splenectomy in children with Gaucher's disease

    International Nuclear Information System (INIS)

    Bar-Maor, J.A.; Govrin-Yehudain, J.

    1985-01-01

    Because of hypersplenism and mechanical problems, partial splenectomy was performed in four children with Gaucher's disease. Subsequently, one of the patients underwent a total splenectomy due to bleeding from the remnant of the spleen. At the follow-up of the other three patients, an isotope scan showed that the remaining spleen was functioning well

  2. Partial Hospitalization Programs: A Current Perspective.

    Science.gov (United States)

    Whitelaw, Carolyn A.; Perez, Edgardo L.

    1987-01-01

    Reviews the historical background, standards, the issue of day treatment versus day care, functional issues, specialization, efficacy and cost effectiveness, utilization issues, and alternative models of care of partial hospitalization programs in North America. Emphasizes issues of relevance when planning alternative programs to inpatient…

  3. Partial chord diagrams and matrix models

    DEFF Research Database (Denmark)

    Andersen, Jørgen Ellegaard; Fuji, Hiroyuki; Manabe, Masahide

    In this article, the enumeration of partial chord diagrams is discussed via matrix model techniques. In addition to the basic data such as the number of backbones and chords, we also consider the Euler characteristic, the backbone spectrum, the boundary point spectrum, and the boundary length spe...

  4. [Elderly people and removable partial dentures

    NARCIS (Netherlands)

    Baat, C. de

    2009-01-01

    The most frequently reported disadvantages of removable partial dentures are the more demanding daily oral hygiene self-care, especially for people who already experience difficulties in self-care, and the possible harmful influence on the remaining dentition. These disadvantages can be expressed in

  5. Dual Component Removable Partial Denture shows improved ...

    African Journals Online (AJOL)

    Dual Component Removable Partial Denture (DuCo RPD) is composed of a double base; lower and upper. The lower base, where the artificial teeth are attached, acts as a support and is in contact with the alveolar ridges and oral mucosa. Clasps are designed on the upper base, which acts towards the retention and ...

  6. Flow visualization via partial differential equations

    NARCIS (Netherlands)

    Preusser, T.; Rumpf, M.; Telea, A.C.; Möller, T.; Hamann, B.; Russell, R.D.

    2009-01-01

    The visualization of stationary and time-dependent flow is an important and chaltenging topic in scientific visualization. lts aim is 10 represent transport phenomena govemed by vector fjelds in an intuitively understandable way. In this paper. we review the use of methods based on partial

  7. [Resin-bonded fixed partial dentures

    NARCIS (Netherlands)

    Kreulen, C.M.; Creugers, N.H.J.

    2013-01-01

    A resin-bonded fixed partial denture is a prosthetic construction which can replace I or several teeth in an occlusal system and which comprises a pontic element which is adhesively attached to 1 or more abutment teeth. To compensate for the limited shear strength of the adhesive layer, the Jixed

  8. Permissive Subsorted Partial Logic in CASL

    DEFF Research Database (Denmark)

    Cerioli, Maura; Haxthausen, Anne Elisabeth; Krieg-Brückner, Bernd

    1997-01-01

    This paper presents a permissive subsorted partial logic used in the CoFI Algebraic Specification Language. In contrast to other order-sorted logics, subsorting is not modeled by set inclusions, but by injective embeddings allowing for more general models in which subtypes can have different data...

  9. Canonical coordinates for partial differential equations

    Science.gov (United States)

    Hunt, L. R.; Villarreal, Ramiro

    1988-01-01

    Necessary and sufficient conditions are found under which operators of the form Sigma (m, j=1) x (2) sub j + X sub O can be made constant coefficient. In addition, necessary and sufficient conditions are derived which classify those linear partial differential operators that can be moved to the Kolmogorov type.

  10. Canonical coordinates for partial differential equations

    Science.gov (United States)

    Hunt, L. R.; Villarreal, Ramiro

    1987-01-01

    Necessary and sufficient conditions are found under which operators of the form Sigma(m, j=1) X(2)sub j + X sub 0 can be made constant coefficient. In addition, necessary and sufficient conditions are derived which classify those linear partial differential operators that can be moved to the Kolmogorov type.

  11. Monitoring as a partially observable decision problem

    Science.gov (United States)

    Paul L. Fackler; Robert G. Haight

    2014-01-01

    Monitoring is an important and costly activity in resource man-agement problems such as containing invasive species, protectingendangered species, preventing soil erosion, and regulating con-tracts for environmental services. Recent studies have viewedoptimal monitoring as a Partially Observable Markov Decision Pro-cess (POMDP), which provides a framework for...

  12. Atomic disintegrations for partially hyperbolic diffeomorphisms

    NARCIS (Netherlands)

    Homburg, Ale Jan

    2017-01-01

    Shub and Wilkinson and Ruelle and Wilkinson studied a class of volume preserving diffeomorphisms on the three dimensional torus that are stably ergodic. The diffeomorphisms are partially hyperbolic and admit an invariant central foliation of circles. The foliation is not absolutely continuous; in

  13. First symposium accelerated partial breast irradiation

    International Nuclear Information System (INIS)

    2012-01-01

    The First symposium accelerated partial breast irradiation, was organized by the Marie Curie Foundation, between the 14 to 16 june 2012, in the Cordoba city of Argentina. In this event were presented some papers on the following topics: radiotherapy in breast cancer; interaction between systemic treatments and radiotherapy; interstitial brachytherapy.

  14. Crichton ambiguities with infinitely many partial waves

    International Nuclear Information System (INIS)

    Atkinson, D.; Kok, L.P.; de Roo, M.

    1978-01-01

    We construct families of spinless two-particle unitary cross sections that possess a nontrivial discrete phase-shift ambiguity, with in general an infinite number of nonvanishing partial waves. A numerical investigation reveals that some of the previously known finite Crichton ambiguities are merely special cases of the newly constructed examples

  15. Group-wise partial least square regression

    NARCIS (Netherlands)

    Camacho, José; Saccenti, Edoardo

    2018-01-01

    This paper introduces the group-wise partial least squares (GPLS) regression. GPLS is a new sparse PLS technique where the sparsity structure is defined in terms of groups of correlated variables, similarly to what is done in the related group-wise principal component analysis. These groups are

  16. Partial axillary dissection in early breast cancer

    African Journals Online (AJOL)

    Tarek Abdel Halim El-Fayoumi

    ORIGINAL ARTICLE. Partial axillary dissection in early breast cancer. Tarek Abdel Halim El-Fayoumi *. Department of General Surgery, Faculty of Medicine, Alexandria University, Egypt. Received 16 October 2012; accepted 7 January 2013. Available online 7 March 2013. KEYWORDS. Breast cancer;. Axillary lymph nodes.

  17. New applications of partial residual methodology

    International Nuclear Information System (INIS)

    Uslu, V.R.

    1999-12-01

    The formulation of a problem of interest in the framework of a statistical analysis starts with collecting the data, choosing a model, making certain assumptions as described in the basic paradigm by Box (1980). This stage is is called model building. Then the estimation stage is in order by pretending as if the formulation of the problem was true to obtain estimates, to make tests and inferences. In the final stage, called diagnostic checking, checking of whether there are some disagreements between the data and the model fitted is done by using diagnostic measures and diagnostic plots. It is well known that statistical methods perform best under the condition that all assumptions related to the methods are satisfied. However it is true that having the ideal case in practice is very difficult. Diagnostics are therefore becoming important so are diagnostic plots because they provide a immediate assessment. Partial residual plots that are the main interest of the present study are playing the major role among the diagnostic plots in multiple regression analysis. In statistical literature it is admitted that partial residual plots are more useful than ordinary residual plots in detecting outliers, nonconstant variance, and especially discovering curvatures. In this study we consider the partial residual methodology in statistical methods rather than multiple regression. We have shown that for the same purpose as in the multiple regression the use of partial residual plots is possible particularly in autoregressive time series models, transfer function models, linear mixed models and ridge regression. (author)

  18. [Designing metal frame removable partial dentures

    NARCIS (Netherlands)

    Witter, D.J.; Barel, J.C.; Keltjens, H.M.A.M.; Creugers, N.H.J.

    2011-01-01

    Oral health care providers have the full responsibility for designing metal frame removable partial dentures and making all of the necessary preparations. Important principles of design are that the denture should hamper natural cleaning and daily oral hygiene as little as possible and that it

  19. psychrometry: from partial pressures to mole fractions

    African Journals Online (AJOL)

    ES Obe

    1980-03-01

    Mar 1, 1980 ... as an ideal gas mixture. Partial pressures then become identical: to mole fractions and sets of psychometric parameters result from rather elementary thermodynamic relations. Search for more accurate data has long led to the realization that neither dry air nor pure water vapour behaves like an ideal gas,.

  20. Partial purification and characterization of metalloprotease of ...

    African Journals Online (AJOL)

    USER

    2013-07-31

    Jul 31, 2013 ... The supplementation of partially purified enzyme preparation in detergents such as Rin and Wheel significantly improved their cleansing efficiency as blood and fish curry stains on the cloth disappeared within 15 min (Figure 6). Our finding go hand in hand with earlier findings on Bacillus licheniformis ...

  1. Partial purification, characterization and hydrolytic activities of ...

    African Journals Online (AJOL)

    α-Amylase and amyloglucosidase produced by amylolytic Bacillus licheniformis and Aspergillus niger isolated from plantain and yam peels media were partially purified and characterized. Following cultivation of the microbial isolates on the agricultural residue media, crude enzyme solutions were obtained by filtration and ...

  2. Partial Evaluation of the Euclidian Algorithm

    DEFF Research Database (Denmark)

    Danvy, Olivier; Goldberg, Mayer

    1997-01-01

    Some programs are easily amenable to partial evaluation because their control flow clearly depends on one of their parameters. Specializing such programs with respect to this parameter eliminates the associated interpretive overhead. Some other programs, however, do not exhibit this interpreter-l...

  3. Exergy of partially coherent thermal radiation

    International Nuclear Information System (INIS)

    Wijewardane, S.; Goswami, Yogi

    2012-01-01

    Exergy of electromagnetic radiation has been studied by a number of researchers for well over four decades in order to estimate the maximum conversion efficiencies of thermal radiation. As these researchers primarily dealt with solar and blackbody radiation, which have a low degree of coherence, they did not consider the partial coherence properties of thermal radiation. With the recent development of surface structures, which can emit radiation with high degree of coherence, the importance of considering the partial coherent properties in exergy calculation has become a necessity as the coherence properties directly influence the entropy of the wave field. Here in this paper we derive an expression for the exergy of quasi-monochromatic radiation using statistical thermodynamics and show that it is identical with the expressions derived using classical thermodynamics. We also present a method to calculate the entropy, thereby the exergy of partially coherent radiation using statistical thermodynamics and a method called matrix treatment of wave field. -- Highlights: ► Considered partial coherence of radiation for the first time to calculate exergy. ► The importance of this method is emphasized with energy conversion examples. ► Derived an expression for the exergy of radiation using statistical thermodynamics. ► Adopted a method to calculate intensity of statistically independent principle wave.

  4. Crichton ambiguities with infinitely many partial waves

    NARCIS (Netherlands)

    Atkinson, D.; Kok, L.P.; de Roo, M.

    We construct families of spin less two-particle unitary cross sections that possess a nontrivial discrete phase-shift ambiguity, with in general an infinite number of nonvanishing partial waves. A numerical investigation reveals that some of the previously known finite Crichton ambiguities are

  5. Partial differential equations in several complex variables

    CERN Document Server

    Chen, So-Chin

    2001-01-01

    This book is intended both as an introductory text and as a reference book for those interested in studying several complex variables in the context of partial differential equations. In the last few decades, significant progress has been made in the fields of Cauchy-Riemann and tangential Cauchy-Riemann operators. This book gives an up-to-date account of the theories for these equations and their applications. The background material in several complex variables is developed in the first three chapters, leading to the Levi problem. The next three chapters are devoted to the solvability and regularity of the Cauchy-Riemann equations using Hilbert space techniques. The authors provide a systematic study of the Cauchy-Riemann equations and the \\bar\\partial-Neumann problem, including L^2 existence theorems on pseudoconvex domains, \\frac 12-subelliptic estimates for the \\bar\\partial-Neumann problems on strongly pseudoconvex domains, global regularity of \\bar\\partial on more general pseudoconvex domains, boundary ...

  6. Partial wave analysis using graphics processing units

    Energy Technology Data Exchange (ETDEWEB)

    Berger, Niklaus; Liu Beijiang; Wang Jike, E-mail: nberger@ihep.ac.c [Institute of High Energy Physics, Chinese Academy of Sciences, 19B Yuquan Lu, Shijingshan, 100049 Beijing (China)

    2010-04-01

    Partial wave analysis is an important tool for determining resonance properties in hadron spectroscopy. For large data samples however, the un-binned likelihood fits employed are computationally very expensive. At the Beijing Spectrometer (BES) III experiment, an increase in statistics compared to earlier experiments of up to two orders of magnitude is expected. In order to allow for a timely analysis of these datasets, additional computing power with short turnover times has to be made available. It turns out that graphics processing units (GPUs) originally developed for 3D computer games have an architecture of massively parallel single instruction multiple data floating point units that is almost ideally suited for the algorithms employed in partial wave analysis. We have implemented a framework for tensor manipulation and partial wave fits called GPUPWA. The user writes a program in pure C++ whilst the GPUPWA classes handle computations on the GPU, memory transfers, caching and other technical details. In conjunction with a recent graphics processor, the framework provides a speed-up of the partial wave fit by more than two orders of magnitude compared to legacy FORTRAN code.

  7. A Partial Theory of Executive Succession.

    Science.gov (United States)

    Thiemann, Francis C.

    This study has two purposes: (1) To construct a partial theory of succession, and (2) to utilize a method of theory construction which combines some of the concepts of Hans Zetterberg with the principles of formal symbolic logic. A bibliography on succession in complex organizations with entries on descriptive and empirical studies from various…

  8. Microbial Flora of Partially Processed Periwinkles (Tympantotonus ...

    African Journals Online (AJOL)

    A survey of microbial flora of partially processed periwinkles (Tympanotonus fuscatus) sold in six markets in Port Harcourt was undertaken for twelve weeks. Results show that all samples of periwinkles were contaminated with Staphylococcus aureus, Bacillus sp., Escherichia coil, Staphepidermidis sp., Micrococcus sp., ...

  9. A computational formalization for partial evaluation

    DEFF Research Database (Denmark)

    Hatcliff, John; Danvy, Olivier

    1997-01-01

    We formalize a partial evaluator for Eugenio Moggi's computational metalanguage. This formalization gives an evaluation-order independent view of binding-time analysis and program specialization, including a proper treatment of call unfolding. It also enables us to express the essence of `control...

  10. A note on partial vertical integration

    NARCIS (Netherlands)

    G.W.J. Hendrikse (George); H.J.M. Peters (Hans)

    1989-01-01

    textabstractA simple model is constructed to show how partial vertical integration may emerge as an equilibrium market structure in a world characterized by rationing, differences in the reservation prices of buyers, and in the risk attitudes of buyers and sellers. The buyers with the high

  11. Memorization in Type-Directed Partial Evaluation

    DEFF Research Database (Denmark)

    Balat, Vincent; Danvy, Olivier

    2002-01-01

    We use a code generator—type-directed partial evaluation— to verify conversions between isomorphic types, or more precisely to verify that a composite function is the identity function at some complicated type. A typed functional language such as ML provides a natural support to express the funct...

  12. Testing the generalized partial credit model

    NARCIS (Netherlands)

    Glas, Cornelis A.W.

    1996-01-01

    The partial credit model (PCM) (G.N. Masters, 1982) can be viewed as a generalization of the Rasch model for dichotomous items to the case of polytomous items. In many cases, the PCM is too restrictive to fit the data. Several generalizations of the PCM have been proposed. In this paper, a

  13. Some Considerations on the Partial Credit Model

    Science.gov (United States)

    Verhelst, N. D.; Verstralen, H. H. F. M.

    2008-01-01

    The Partial Credit Model (PCM) is sometimes interpreted as a model for stepwise solution of polytomously scored items, where the item parameters are interpreted as difficulties of the steps. It is argued that this interpretation is not justified. A model for stepwise solution is discussed. It is shown that the PCM is suited to model sums of binary…

  14. How to test for partially predictable chaos.

    Science.gov (United States)

    Wernecke, Hendrik; Sándor, Bulcsú; Gros, Claudius

    2017-04-24

    For a chaotic system pairs of initially close-by trajectories become eventually fully uncorrelated on the attracting set. This process of decorrelation can split into an initial exponential decrease and a subsequent diffusive process on the chaotic attractor causing the final loss of predictability. Both processes can be either of the same or of very different time scales. In the latter case the two trajectories linger within a finite but small distance (with respect to the overall extent of the attractor) for exceedingly long times and remain partially predictable. Standard tests for chaos widely use inter-orbital correlations as an indicator. However, testing partially predictable chaos yields mostly ambiguous results, as this type of chaos is characterized by attractors of fractally broadened braids. For a resolution we introduce a novel 0-1 indicator for chaos based on the cross-distance scaling of pairs of initially close trajectories. This test robustly discriminates chaos, including partially predictable chaos, from laminar flow. Additionally using the finite time cross-correlation of pairs of initially close trajectories, we are able to identify laminar flow as well as strong and partially predictable chaos in a 0-1 manner solely from the properties of pairs of trajectories.

  15. Pragmatics of type-directed partial evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1996-01-01

    Type-directed partial evaluation stems from the residualization of static values in dynamic contexts, given their type and the type of their free variables. Its algorithm coincides with the algorithm for coercing a subtype value into a supertype value, which itself coincides with Berger and Schwi...

  16. Complete destructive interference of partially coherent fields

    NARCIS (Netherlands)

    Gbur, G.J.; Visser, T.D.; Wolf, E.

    2004-01-01

    A three-point source model is used to study the interference of wavefields which are mutually partially coherent. It is shown that complete destructive interference of the fields is possible in such a "three-pinhole interferometer" even if the sources are not fully coherent with respect to each

  17. Partial Polarization in Interfered Plasmon Fields

    Directory of Open Access Journals (Sweden)

    P. Martínez Vara

    2014-01-01

    Full Text Available We describe the polarization features for plasmon fields generated by the interference between two elemental surface plasmon modes, obtaining a set of Stokes parameters which allows establishing a parallelism with the traditional polarization model. With the analysis presented, we find the corresponding coherence matrix for plasmon fields incorporating to the plasmon optics the study of partial polarization effects.

  18. Partial Automated Alignment and Integration System

    Science.gov (United States)

    Kelley, Gary Wayne (Inventor)

    2014-01-01

    The present invention is a Partial Automated Alignment and Integration System (PAAIS) used to automate the alignment and integration of space vehicle components. A PAAIS includes ground support apparatuses, a track assembly with a plurality of energy-emitting components and an energy-receiving component containing a plurality of energy-receiving surfaces. Communication components and processors allow communication and feedback through PAAIS.

  19. Design of multistable systems via partial synchronization

    Indian Academy of Sciences (India)

    Mohammad Ali Khan

    2017-07-05

    Jul 5, 2017 ... The basic idea of the scheme is to design partial synchronization of states between the coupled systems and ... Numerical simulation results consisting of ... systems of the same order via active control is discussed. In §3, the ...

  20. Partially Decentralized Control Architectures for Satellite Formations

    Science.gov (United States)

    Carpenter, J. Russell; Bauer, Frank H.

    2002-01-01

    In a partially decentralized control architecture, more than one but less than all nodes have supervisory capability. This paper describes an approach to choosing the number of supervisors in such au architecture, based on a reliability vs. cost trade. It also considers the implications of these results for the design of navigation systems for satellite formations that could be controlled with a partially decentralized architecture. Using an assumed cost model, analytic and simulation-based results indicate that it may be cheaper to achieve a given overall system reliability with a partially decentralized architecture containing only a few supervisors, than with either fully decentralized or purely centralized architectures. Nominally, the subset of supervisors may act as centralized estimation and control nodes for corresponding subsets of the remaining subordinate nodes, and act as decentralized estimation and control peers with respect to each other. However, in the context of partially decentralized satellite formation control, the absolute positions and velocities of each spacecraft are unique, so that correlations which make estimates using only local information suboptimal only occur through common biases and process noise. Covariance and monte-carlo analysis of a simplified system show that this lack of correlation may allow simplification of the local estimators while preserving the global optimality of the maneuvers commanded by the supervisors.

  1. A partial account of presupposition projection

    NARCIS (Netherlands)

    Beaver, D.; Krahmer, E.J.

    2001-01-01

    In this paper it is shown how a partial semantics for presuppositions can be given which is empirically more satisfactory than its predecessors, and how this semantics can be integrated with a technically sound, compositional grammar in the Montagovian fashion. Additionally, it is argued that the

  2. Pipeline transportation of emerging partially upgraded bitumen

    International Nuclear Information System (INIS)

    Luhning, R.W.; Anand, A.; Blackmore, T.; Lawson, D.S.

    2002-01-01

    The recoverable reserves of Canada's vast oil deposits is estimated to be 335 billion barrels (bbl), most of which are in the Alberta oil sands. Canada was the largest import supplier of crude oil to the United States in 2001, followed by Saudi Arabia. By 2011, the production of oil sands is expected to increase to 50 per cent of Canada's oil, and conventional oil production will decline as more production will be provided by synthetic light oil and bitumen. This paper lists the announced oil sands projects. If all are to proceed, production would reach 3,445,000 bbl per day by 2011. The three main challenges regarding the transportation and marketing of this new production were described. The first is to expand the physical capacity of existing pipelines. The second is the supply of low viscosity diluent (such as natural gas condensate or synthetic diluent) to reduce the viscosity and density of the bitumen as it passes through the pipelines. The current pipeline specifications and procedures to transport partially upgraded products are presented. The final challenge is the projected refinery market constraint to process the bitumen and synthetic light oil into consumer fuel products. These challenges can be addressed by modifying refineries and increasing Canadian access in Petroleum Administration Defense District (PADD) II and IV. The technology for partial upgrading of bitumen to produce pipeline specification oil, reduce diluent requirements and add sales value, is currently under development. The number of existing refineries to potentially accept partially upgraded product is listed. The partially upgraded bitumen will be in demand for additional upgrading to end user products, and new opportunities will be presented as additional pipeline capacity is made available to transport crude to U.S. markets and overseas. The paper describes the following emerging partial upgrading methods: the OrCrude upgrading process, rapid thermal processing, CPJ process for

  3. Treatment planning: implant-supported partial overdentures.

    Science.gov (United States)

    Chee, Winston W L

    2005-04-01

    When multiple anterior teeth are missing, many options of replacement are available. Traditionally, the choice was between a fixed or removable prostheses. Today, with the predictability of dental implants, the options of tooth replacement range from removable partial dentures to implant-supported fixed prostheses. The choice of which restoration that will best provide occlusion and esthetics depends on multiple factors including the number and location of missing teeth, the residual ridge form in relation to the replacement teeth, the relationship of the maxillary and mandibular anterior teeth, the condition of teeth adjacent to the edentulous span, the amount of bone available for implant placement, the patients "smile line" and display of teeth, lip support, and financial constraints. When there is minimal loss of the ridge contour, restorations that emerge from the ridge are the most functional and esthetic restorations, adhesive-type fixed partial dentures, conventional fixed partial dentures, and implant-supported restorations can be indicated with the choice of restoration dependent on a risk benefit and cost benefit analysis. When there is a loss of ridge contour due to residual ridge resorption or trauma, the decision becomes more complex as not only does the tooth structure need to be replaced, the ridge form also has to be replaced. (Figures 1 and 2). This can be assessed clinically as illustrated by Figures 1 and 2 where a dis crepancy in arch form and ridge form in relation to the adjacent teeth and/or opposing arch can be observed. Other considerations are lip support and display of the teeth when smiling. This article presents a case and rationale for implant-supported par tial overdentures. Many authors have written on the merits of com plete overdentures. The complete overdenture has proven to be an improvement over conventional complete prostheses with respect to chewing efficiency, patient comfort and satisfaction. In partial edentulism, the

  4. [Partial splenectomy in sickle cell disease].

    Science.gov (United States)

    Gutiérrez Díaz, A I; Svarch, E; Arencibia Núñez, A; Sabournin Ferrier, V; Machín García, S; Menendez Veitía, A; Ramón Rodriguez, L; Serrano Mirabal, J; García Peralta, T; López Martin, L G

    2015-04-01

    Total splenectomy in sickle cell disease is related to a high risk of fulminant sepsis and increased incidence of other events, which have not been reported in patients with partial splenectomy. In this study we examined the patients with sickle cell disease and partial splenectomy and compared the clinical and laboratory results with non-splenectomized patients. We studied 54 patients with sickle cell disease who underwent partial splenectomy in childhood from 1986 until 2011 at the Institute of Hematology and Immunology. They were compared with 54 non-splenectomized patients selected by random sampling with similar characteristics. Partial splenectomy was performed at a mean age of 4.1 years, with a higher frequency in homozygous hemoglobin S (70.4%), and the most common cause was recurrent splenic sequestration crisis. The most common postoperative complications were fever of unknown origin (14.8%) and acute chest syndrome (11.1%). After splenectomy there was a significant increase in leukocytes, neutrophils, and platelets, the latter two parameters remained significantly elevated when compared with non-splenectomized patients. There was no difference in the incidence of clinical events, except hepatic sequestration, which was more common in splenectomized patients. Partial splenectomy was a safe procedure in patients with sickle cell disease. There were no differences in the clinical picture in children splenectomized and non-splenectomized except the greater frequency of hepatic sequestration crisis in the first group. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

  5. Monotherapy for partial epilepsy: focus on levetiracetam

    Directory of Open Access Journals (Sweden)

    Antonio Gambardella

    2008-03-01

    Full Text Available Antonio Gambardella1,2, Angelo Labate1,2, Eleonora Colosimo1, Roberta Ambrosio1, Aldo Quattrone1,21Institute of Neurology, University Magna Græcia, Catanzaro, Italy; 2Institute of Neurological Sciences, National Research Council, Piano Lago di Mangone, Cosenza, ItalyAbstract: Levetiracetam (LEV, the S-enantiomer of alpha-ethyl-2-oxo-1-pyrollidine acetamide, is a recently licensed antiepileptic drug (AED for adjunctive therapy of partial seizures. Its mechanism of action is uncertain but it exhibits a unique profile of anticonvulsant activity in models of chronic epilepsy. Five randomized, double-blind, placebo-controlled trials enrolling adult or pediatric patients with refractory partial epilepsy have demonstrated the efficacy of LEV as adjunctive therapy, with a responder rate (≥50% reduction in seizure frequency of 28%–45%. Long-term efficacy studies suggest retention rates of 60% after one year, with 13% of patients seizure-free for 6 months of the study and 8% seizure-free for 1 year. More recent studies illustrated successful conversion to monotherapy in patients with refractory epilepsy, and its effectiveness as a single agent in partial epilepsy. LEV has also efficacy in generalized epilepsies. Adverse effects of LEV, including somnolence, lethargy, and dizziness, are generally mild and their occurrence rate seems to be not significantly different from that observed in placebo groups. LEV also has no clinically significant pharmacokinetic interactions with other AEDs, or with commonly prescribed medications. The combination of effective antiepileptic properties with a relatively mild adverse effect profile makes LEV an attractive therapy for partial seizures.Keywords: levetiracetam, partial epilepsy, antiepileptic drugs

  6. PARTIAL TRISOMY 4p AND PARTIAL MONOSOMY 13q: CASE REPORT AND A LITERATURE REVIEW.

    Science.gov (United States)

    Puvabanditsin, S; Herrera-Garcia, G; Gengel, N; Hussein, K; February, M; Mayne, J; Mehta, R

    2016-01-01

    We report on a term first born dichorionic-diamniotic twin with deletion of the distal long arm of chromosome 13, partial trisomy of the short arm of chromosome 4, intrauterine growth retardation, and multiple anomalies including microcephaly, colpocephaly, absent corpus callosum, bulbous tip of the nose, large and low set ears, macroglossia, thin upper lip, double outlet right ventricle, atria/ventricular septal defect, cleft mitral valve, pulmonary stenosis, single umbilical artery, multicystic dysplastic left kidney, sacral dimple, anterior displacement of anus, simian creases, abnormal thumb (congenital clasped thumb), overlapping toes, and congenital hypothyroidism. This is the first report of a patient with partial trisomy 4p and partial monosomy 13q.

  7. 40 CFR Table 7 to Subpart Vvvvvv... - Partially Soluble HAP

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 14 2010-07-01 2010-07-01 false Partially Soluble HAP 7 Table 7 to... Pt. 63, Subpt. VVVVVV, Table 7 Table 7 to Subpart VVVVVV of Part 63—Partially Soluble HAP As required... partially soluble HAP listed in the following table. Partially soluble HAP name CAS No. 1. 1,1,1...

  8. Partial rectangular metric spaces and fixed point theorems.

    Science.gov (United States)

    Shukla, Satish

    2014-01-01

    The purpose of this paper is to introduce the concept of partial rectangular metric spaces as a generalization of rectangular metric and partial metric spaces. Some properties of partial rectangular metric spaces and some fixed point results for quasitype contraction in partial rectangular metric spaces are proved. Some examples are given to illustrate the observed results.

  9. Magnetic properties of partially oxidized Fe films

    Science.gov (United States)

    Garcia, Miguel Angel; Lopez-Dominguez, Victor; Hernando, Antonio

    Hybrid magnetic nanostructures exhibit appealing properties due to interface and proximity effects. A simple and interesting system of hybrid magnetic nanomaterials are partially oxidized ferromagnetic films. We have fabricated Fe films by thermal evaporation and performed a partial oxidation to magnetite (Fe3O4) by annealing in air at different times and temperatures. The magnetic properties of the films evolve from those of pure metallic iron to pure magnetite, showing intermediate states where the proximity effects control the magnetic behavior. At some stages, the magnetization curves obtained by SQUID and MOKE magnetometry exhibit important differences due to the dissimilar contribution of both phases to the magneto-optical response of the system This work has been supported by the Ministerio Español de Economia y Competitividad (MINECO) MAT2013-48009-C4-1. V.L.D and M.A.G. acknowledges financial support from BBVA foundation.

  10. Local cerebral metabolism during partial seizures

    International Nuclear Information System (INIS)

    Engel, J. Jr.; Kuhl, D.E.; Phelps, M.E.; Rausch, R.; Nuwer, M.

    1983-01-01

    Interictal and ictal fluorodeoxyglucose scans were obtained with positron CT from four patients with spontaneous recurrent partial seizures, one with epilepsia partialis continua, and one with a single partial seizure induced by electrical stimulation of the hippocampus. Ictal metabolic patterns were different for each patient studied. Focal and generalized increased and decreased metabolism were observed. Ictal hypermetabolism may exceed six times the interictal rate and could represent activation of excitatory or inhibitory synapses in the epileptogenic region and its projection fields. Hypometabolism seen on ictal scans most likely reflects postictal depression and may indicate projection fields of inhibited neurons. No quantitative relationship between alterations in metabolism and EEG or behavioral measurements of ictal events could be demonstrated

  11. Partial peritoneal alimentation in an infant.

    Science.gov (United States)

    Merritt, R J; Atkinson, J B; Whalen, T V; Thomas, D W; Sinatra, F R; Roloson, G J

    1988-01-01

    We provided partial peritoneal alimentation to a 1.69-kg 11-month-old premature infant who had no available central venous access, depleted peripheral venous access, and gastrointestinal dysfunction. A cuffed silastic catheter was surgically inserted into the suprahepatic space. An alimentation solution was continuously infused into the peritoneum for 28 days to supplement peripheral venous and nasogastric alimentation and contributed 42 +/- 15% of total calories daily. Weight gain was achieved, but complications included hypoglycemia, hypophosphatemia, intravascular dehydration, catheter site leakage, ascites, and hydrocele. At autopsy 11 months later, lipid accumulation was present in the upper peritoneum and the hilar regions of the lungs secondary to preexisting lymphatic obstruction. Partial peritoneal alimentation may be feasible when other access routes are inadequate, but lymphatic obstruction is a contraindication to the peritoneal administration of lipid emulsions.

  12. An Imperative Type Hierarchy with Partial Products

    DEFF Research Database (Denmark)

    Schwartzbach, Michael Ignatieff; Schmidt, Erik Meineche

    1989-01-01

    notation for defining recursive types, that is superior to traditional type sums and products. We show how the ordering on types extends to an ordering on types with invariants. We allow the use of least upper bounds in type definitions and show how to compute upper bounds of invariants.......A type hierarchy for a programming language defines an ordering on the types such that any application for small types may be reused for all larger types. The imperative facet makes this non-trivial; the straight-forward definitions will yield an inconsistent system. We introduce a new type...... constructor, the partial product, and show how to define a consistent hierarchy in the context of fully recursive types. A simple polymorphism is derived by introducing a notion of placeholder types. By extending the partial product types to include structural invariants we obtain a particularly appropriate...

  13. Effective stress principle for partially saturated media

    International Nuclear Information System (INIS)

    McTigue, D.F.; Wilson, R.K.; Nunziato, J.W.

    1984-04-01

    In support of the Nevada Nuclear Waste Storage Investigation (NNWSI) Project, we have undertaken a fundamental study of water migration in partially saturated media. One aspect of that study, on which we report here, has been to use the continuum theory of mixtures to extend the classical notion of effective stress to partially saturated media. Our analysis recovers previously proposed phenomenological representations for the effective stress in terms of the capillary pressure. The theory is illustrated by specializing to the case of linear poroelasticity, for which we calculate the deformation due to the fluid pressure in a static capillary fringe. We then examine the transient consolidation associated with liquid flow induced by an applied surface load. Settlement accompanies this flow as the liquid is redistributed by a nonlinear diffusion process. For material properties characteristic of tuff from the Nevada Test Site, these effects are found to be vanishingly small. 14 references, 7 figures, 1 table

  14. Partial differential operators of elliptic type

    CERN Document Server

    Shimakura, Norio

    1992-01-01

    This book, which originally appeared in Japanese, was written for use in an undergraduate course or first year graduate course in partial differential equations and is likely to be of interest to researchers as well. This book presents a comprehensive study of the theory of elliptic partial differential operators. Beginning with the definitions of ellipticity for higher order operators, Shimakura discusses the Laplacian in Euclidean spaces, elementary solutions, smoothness of solutions, Vishik-Sobolev problems, the Schauder theory, and degenerate elliptic operators. The appendix covers such preliminaries as ordinary differential equations, Sobolev spaces, and maximum principles. Because elliptic operators arise in many areas, readers will appreciate this book for the way it brings together a variety of techniques that have arisen in different branches of mathematics.

  15. Crowdfunding Through a Partial Organization Lens

    DEFF Research Database (Denmark)

    Nielsen, Kristian Roed

    2018-01-01

    Crowdfunding has become a rapidly growing source of alternative financing for a wide range of products and service ideas. The crowdfunding process itself necessitates the successful interaction between a number of actors including the central organizing platform, a number of content providing...... campaigns, and a large diverse group of funders. By utilizing the literature on complete and partial organizations and rejecting the commonly applied organizational molds to describe the process, this paper proposes that crowdfunding is organized and enabled as a fluid and co-dependent interaction between...... the various actors. The concept of partial organizations and its emphasis on key organizational decisions reveal that crowdfunding may be conceived of as a “co-dependent organization” in which the relationship of the involved actors is so interdependent that the crowdfunding process can neither be maintained...

  16. Local cerebral metabolism during partial seizures

    Energy Technology Data Exchange (ETDEWEB)

    Engel, J. Jr.; Kuhl, D.E.; Phelps, M.E.; Rausch, R.; Nuwer, M.

    1983-04-01

    Interictal and ictal fluorodeoxyglucose scans were obtained with positron CT from four patients with spontaneous recurrent partial seizures, one with epilepsia partialis continua, and one with a single partial seizure induced by electrical stimulation of the hippocampus. Ictal metabolic patterns were different for each patient studied. Focal and generalized increased and decreased metabolism were observed. Ictal hypermetabolism may exceed six times the interictal rate and could represent activation of excitatory or inhibitory synapses in the epileptogenic region and its projection fields. Hypometabolism seen on ictal scans most likely reflects postictal depression and may indicate projection fields of inhibited neurons. No quantitative relationship between alterations in metabolism and EEG or behavioral measurements of ictal events could be demonstrated.

  17. Bactericidal activity of partially oxidized nanodiamonds.

    Science.gov (United States)

    Wehling, Julia; Dringen, Ralf; Zare, Richard N; Maas, Michael; Rezwan, Kurosch

    2014-06-24

    Nanodiamonds are a class of carbon-based nanoparticles that are rapidly gaining attention, particularly for biomedical applications, i.e., as drug carriers, for bioimaging, or as implant coatings. Nanodiamonds have generally been considered biocompatible with a broad variety of eukaryotic cells. We show that, depending on their surface composition, nanodiamonds kill Gram-positive and -negative bacteria rapidly and efficiently. We investigated six different types of nanodiamonds exhibiting diverse oxygen-containing surface groups that were created using standard pretreatment methods for forming nanodiamond dispersions. Our experiments suggest that the antibacterial activity of nanodiamond is linked to the presence of partially oxidized and negatively charged surfaces, specifically those containing acid anhydride groups. Furthermore, proteins were found to control the bactericidal properties of nanodiamonds by covering these surface groups, which explains the previously reported biocompatibility of nanodiamonds. Our findings describe the discovery of an exciting property of partially oxidized nanodiamonds as a potent antibacterial agent.

  18. Absolute partial photoionization cross sections of ethylene

    Science.gov (United States)

    Grimm, F. A.; Whitley, T. A.; Keller, P. R.; Taylor, J. W.

    1991-07-01

    Absolute partial photoionization cross sections for ionization out of the first four valence orbitals to the X 2B 3u, A 2B 3g, B 2A g and C 2B 2u states of the C 2H 4+ ion are presented as a function of photon energy over the energy range from 12 to 26 eV. The experimental results have been compared to previously published relative partial cross sections for the first two bands at 18, 21 and 24 eV. Comparison of the experimental data with continuum multiple scattering Xα calculations provides evidence for extensive autoionization to the X 2B 3u state and confirms the predicted shape resonances in ionization to the A 2B 3g and B 2A g states. Identification of possible transitions for the autoionizing resonances have been made using multiple scattering transition state calculations on Rydberg excited states.

  19. Partial Androgen Insensitivity Syndrome Presenting with Gynecomastia

    Directory of Open Access Journals (Sweden)

    Sung Won Lee

    2015-06-01

    Full Text Available Gynecomastia is a benign enlargement of the male breast caused by the proliferation of glandular breast tissue. Determining the various causes of gynecomastia such as physiological causes, drugs, systemic diseases, and endocrine disorders is important. Androgen insensitivity syndrome (AIS is a rare endocrine disorder presenting with gynecomastia and is a disorder of male sexual differentiation caused by mutations within the androgen receptor gene. All individuals with AIS have the 46 XY karyotype, although AIS phenotypes can be classified as mild, partial or complete and can differ among both males and females including ambiguous genitalia or infertility in males. We experienced a case of partial AIS presenting with gynecomastia and identified the androgen receptor gene mutation.

  20. Neuromuscular Exercise Post Partial Medial Meniscectomy

    DEFF Research Database (Denmark)

    Hall, Michelle; Hinman, Rana S; Wrigley, Tim V

    2015-01-01

    PURPOSE: To evaluate the effects of a 12-week, home-based, physiotherapist-guided neuromuscular exercise program on the knee adduction moment (an indicator of mediolateral knee load distribution) in people with a medial arthroscopic partial meniscectomy within the past 3-12 months. METHODS......: An assessor-blinded, randomised controlled trial including people aged 30-50 years with no to mild pain following medial arthroscopic partial meniscectomy was conducted. Participants were randomly allocated to either a 12-week neuromuscular exercise program that targeted neutral lower limb alignment...... or a control group with no exercise. The exercise program included eight individual sessions with one of seven physiotherapists in private clinics, together with home exercises. Primary outcomes were the peak external knee adduction moment during normal pace walking and during a one-leg sit-to-stand. Secondary...

  1. Partial cross sections in H- photodetachment

    International Nuclear Information System (INIS)

    Halka, M.

    1993-04-01

    This dissertation reports experimental measurements of partial decay cross sections in the H - photodetachment spectrum. Observed decays of the 1 P 0 H -** (n) doubly-excitedresonances to the H(N=2) continuum are reported for n=2,3, and 4 from 1990 runs in which the author participated. A recent analysis of 1989 data revealing effects of static electric fields on the partial decay spectrum above 13.5 eV is also presented. The experiments were performed at the High Resolution Atomic Beam Facility. the Los Alamos Meson Physics Facility, with a relativistic H - beam (β=0.842)intersecting a ND:YAG laser. Variation of the intersection angle amounts to Doppler-shifting the photon energy, allowing continuous tuning of the laser energy as viewed from the moving ions' frame

  2. Stochastic partial differential equations an introduction

    CERN Document Server

    Liu, Wei

    2015-01-01

    This book provides an introduction to the theory of stochastic partial differential equations (SPDEs) of evolutionary type. SPDEs are one of the main research directions in probability theory with several wide ranging applications. Many types of dynamics with stochastic influence in nature or man-made complex systems can be modelled by such equations. The theory of SPDEs is based both on the theory of deterministic partial differential equations, as well as on modern stochastic analysis. Whilst this volume mainly follows the ‘variational approach’, it also contains a short account on the ‘semigroup (or mild solution) approach’. In particular, the volume contains a complete presentation of the main existence and uniqueness results in the case of locally monotone coefficients. Various types of generalized coercivity conditions are shown to guarantee non-explosion, but also a systematic approach to treat SPDEs with explosion in finite time is developed. It is, so far, the only book where the latter and t...

  3. Computing the partial volume of pressure vessels

    Energy Technology Data Exchange (ETDEWEB)

    Wiencke, Bent [Nestle USA, Corporate Engineering, 800 N. Brand Blvd, Glendale, CA 91203 (United States)

    2010-06-15

    The computation of the partial and total volume of pressure vessels with various type of head profiles requires detailed knowledge of the head profile geometry. Depending on the type of head profile the derivation of the equations can become very complex and the calculation process cumbersome. Certain head profiles require numerical methods to obtain the partial volume, which for most application is beyond the scope of practicability. This paper suggests a unique method that simplifies the calculation procedure for the various types of head profiles by using one common set of equations without the need for numerical or complex computation methods. For ease of use, all equations presented in this paper are summarized in a single table format for horizontal and vertical vessels. (author)

  4. Deterministic dense coding with partially entangled states

    Science.gov (United States)

    Mozes, Shay; Oppenheim, Jonathan; Reznik, Benni

    2005-01-01

    The utilization of a d -level partially entangled state, shared by two parties wishing to communicate classical information without errors over a noiseless quantum channel, is discussed. We analytically construct deterministic dense coding schemes for certain classes of nonmaximally entangled states, and numerically obtain schemes in the general case. We study the dependency of the maximal alphabet size of such schemes on the partially entangled state shared by the two parties. Surprisingly, for d>2 it is possible to have deterministic dense coding with less than one ebit. In this case the number of alphabet letters that can be communicated by a single particle is between d and 2d . In general, we numerically find that the maximal alphabet size is any integer in the range [d,d2] with the possible exception of d2-1 . We also find that states with less entanglement can have a greater deterministic communication capacity than other more entangled states.

  5. Oxygen partial pressure sensor for gases

    International Nuclear Information System (INIS)

    Barbero, J.A.; Azcona, M.A.; Orce, A.

    1997-01-01

    Precise measurement of very low oxygen partial pressure is important in both laboratories and industries. Particularly in nuclear industry, it is relevant in the different steps of the nuclear fuel fabrication. It is presented an instrument which is handy and of easy construction, suitable for the measurement of oxygen partial pressure of gases, in the range of 10 -6 -1 atm. It is based on a solid electrolyte galvanic cell, using Yttria doped zirconia as a ceramic membrane. Through an indirect measurement and calibration, the instrument can be used to measure the content of free oxygen in liquids. It is a import feature in NPP instrumentation. The equipment was calibrated with mixtures of special nonreactive gases. (author). 5 refs

  6. Oxygen partial pressure sensor for gases

    Energy Technology Data Exchange (ETDEWEB)

    Barbero, J.A.; Azcona, M.A.; Orce, A. [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche

    1997-10-01

    Precise measurement of very low oxygen partial pressure is important in both laboratories and industries. Particularly in nuclear industry, it is relevant in the different steps of the nuclear fuel fabrication. It is presented an instrument which is handy and of easy construction, suitable for the measurement of oxygen partial pressure of gases, in the range of 10{sup -6}-1 atm. It is based on a solid electrolyte galvanic cell, using Yttria doped zirconia as a ceramic membrane. Through an indirect measurement and calibration, the instrument can be used to measure the content of free oxygen in liquids. It is a import feature in NPP instrumentation. The equipment was calibrated with mixtures of special nonreactive gases. (author). 5 refs.

  7. Hamiltonian partial differential equations and applications

    CERN Document Server

    Nicholls, David; Sulem, Catherine

    2015-01-01

    This book is a unique selection of work by world-class experts exploring the latest developments in Hamiltonian partial differential equations and their applications. Topics covered within are representative of the field’s wide scope, including KAM and normal form theories, perturbation and variational methods, integrable systems, stability of nonlinear solutions as well as applications to cosmology, fluid mechanics and water waves. The volume contains both surveys and original research papers and gives a concise overview of the above topics, with results ranging from mathematical modeling to rigorous analysis and numerical simulation. It will be of particular interest to graduate students as well as researchers in mathematics and physics, who wish to learn more about the powerful and elegant analytical techniques for Hamiltonian partial differential equations.

  8. Esthetic double-structure fixed partial dentures.

    Science.gov (United States)

    Ravasini, G; Ugolini, G; Ravasini, F

    1996-04-01

    A new technical procedure for fixed partial dentures and single inlays allows the use of a metal supporting structure with independent ceramic coverage. The advantages of the technique are the bonding of metal to beveled dentinal margins with conventional cement and the acid-etched resin composite cementation of the ceramic, which permits more conservative preparation of the teeth. The complexity of the structure, the laboratory costs, and the doubling of the cementation procedures are the main disadvantages of the technique.

  9. Spreading paths in partially observed social networks

    OpenAIRE

    Onnela, Jukka-Pekka; Christakis, Nicholas A.

    2012-01-01

    Understanding how and how far information, behaviors, or pathogens spread in social networks is an important problem, having implications for both predicting the size of epidemics, as well as for planning effective interventions. There are, however, two main challenges for inferring spreading paths in real-world networks. One is the practical difficulty of observing a dynamic process on a network, and the other is the typical constraint of only partially observing a network. Using a static, s...

  10. Removable partial dentures: use of rapid prototyping.

    Science.gov (United States)

    Lima, Julia Magalhaes Costa; Anami, Lilian Costa; Araujo, Rodrigo Maximo; Pavanelli, Carlos A

    2014-10-01

    The CAD/CAM technology associated with rapid prototyping (RP) is already widely used in the fabrication of all-ceramic fixed prostheses and in the biomedical area; however, the use of this technology for the manufacture of metal frames for removable dentures is new. This work reports the results of a literature review conducted on the use of CAD/CAM and RP in the manufacture of removable partial dentures. © 2014 by the American College of Prosthodontists.

  11. Partially closed fuel cycle of WWER-440

    International Nuclear Information System (INIS)

    Darilek, P.; Sebian, V.; Necas, V.

    2002-01-01

    Position of nuclear energy at the energy sources competition is characterised briefly. Multi-tier transmutation system is outlined out as effective back-end solution and consequently as factor that can increase nuclear energy competitiveness. LWR and equivalent WWER are suggested as a first tier reactors. Partially closed fuel cycle with combined fuel assemblies is briefed. Main back-end effects are characterised (Authors)

  12. Laterally Loaded Partially Prestressed Concrete Piles

    Science.gov (United States)

    1989-09-01

    of an extensive test program onl laterali y ioadeu. partially pr- estressed concrete fender piles. The study Included service load range as well ats...12,000-psi design strength). Configura- tion G utilized 14 r:- estress strand, in an unsymmetric pattern. To provide a uniform concrete prestress of 540...sudden loss in load carrying capacity directly related to the loss of concrete area. The compression concrete fractured longitudinally and along the

  13. Observability of discretized partial differential equations

    Science.gov (United States)

    Cohn, Stephen E.; Dee, Dick P.

    1988-01-01

    It is shown that complete observability of the discrete model used to assimilate data from a linear partial differential equation (PDE) system is necessary and sufficient for asymptotic stability of the data assimilation process. The observability theory for discrete systems is reviewed and applied to obtain simple observability tests for discretized constant-coefficient PDEs. Examples are used to show how numerical dispersion can result in discrete dynamics with multiple eigenvalues, thereby detracting from observability.

  14. The partially filled viscous ring damper.

    Science.gov (United States)

    Alfriend, K. T.

    1973-01-01

    The problem of a spinning satellite with a partially filled viscous ring damper is investigated. It is shown that there are two distinct modes of motion, the nutation-synchronous mode and spin-synchronous mode. From an approximate solution of the equations of motion a time constant is obtained for each mode. From a consideration of the fluid dynamics several methods are developed for determining the damping constant.

  15. Exploiting partial knowledge for efficient model analysis

    OpenAIRE

    Macedo, Nuno; Cunha, Alcino; Pessoa, Eduardo José Dias

    2017-01-01

    The advancement of constraint solvers and model checkers has enabled the effective analysis of high-level formal specification languages. However, these typically handle a specification in an opaque manner, amalgamating all its constraints in a single monolithic verification task, which often proves to be a performance bottleneck. This paper addresses this issue by proposing a solving strategy that exploits user-provided partial knowledge, namely by assigning symbolic bounds to the problem’s ...

  16. Ambit processes and stochastic partial differential equations

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole; Benth, Fred Espen; Veraart, Almut

    Ambit processes are general stochastic processes based on stochastic integrals with respect to Lévy bases. Due to their flexible structure, they have great potential for providing realistic models for various applications such as in turbulence and finance. This papers studies the connection betwe...... ambit processes and solutions to stochastic partial differential equations. We investigate this relationship from two angles: from the Walsh theory of martingale measures and from the viewpoint of the Lévy noise analysis....

  17. A partial snake for the AGS

    International Nuclear Information System (INIS)

    Ratner, L.G.

    1990-01-01

    Based on snake experiments at the Indian University Cyclotron Facility and computer simulations at Brookhaven National Laboratory, as well as the conclusions of a BNL mini-workshop, we feel that a partial Siberian snake is a practical device for the AGS. It is anticipated that such a device could reduce the polarized beam tune-up time from 2--3 weeks to 2--3 days

  18. Extinction of laminar partially premixed flames

    Energy Technology Data Exchange (ETDEWEB)

    Aggarwal, Suresh K. [Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, 842 W. Taylor Street, Room 2039, MC-251, Chicago, IL 60607-7022 (United States)

    2009-12-15

    Flame extinction represents one of the classical phenomena in combustion science. It is important to a variety of combustion systems in transportation and power generation applications. Flame extinguishment studies are also motivated from the consideration of fire safety and suppression. Such studies have generally considered non-premixed and premixed flames, although fires can often originate in a partially premixed mode, i.e., fuel and oxidizer are partially premixed as they are transported to the reaction zone. Several recent investigations have considered this scenario and focused on the extinction of partially premixed flames (PPFs). Such flames have been described as hybrid flames possessing characteristics of both premixed and non-premixed flames. This paper provides a review of studies dealing with the extinction of PPFs, which represent a broad family of flames, including double, triple (tribrachial), and edge flames. Theoretical, numerical and experimental studies dealing with the extinction of such flames in coflow and counterflow configurations are discussed. Since these flames contain both premixed and non-premixed burning zones, a brief review of the dilution-induced extinction of premixed and non-premixed flames is also provided. For the coflow configuration, processes associated with flame liftoff and blowout are described. Since lifted non-premixed jet flames often contain a partially premixed or an edge-flame structure prior to blowout, the review also considers such flames. While the perspective of this review is broad focusing on the fundamental aspects of flame extinction and blowout, results mostly consider flame extinction caused by the addition of a flame suppressant, with relevance to fire suppression on earth and in space environment. With respect to the latter, the effect of gravity on the extinction of PPFs is discussed. Future research needs are identified. (author)

  19. First-order partial differential equations

    CERN Document Server

    Rhee, Hyun-Ku; Amundson, Neal R

    2001-01-01

    This first volume of a highly regarded two-volume text is fully usable on its own. After going over some of the preliminaries, the authors discuss mathematical models that yield first-order partial differential equations; motivations, classifications, and some methods of solution; linear and semilinear equations; chromatographic equations with finite rate expressions; homogeneous and nonhomogeneous quasilinear equations; formation and propagation of shocks; conservation equations, weak solutions, and shock layers; nonlinear equations; and variational problems. Exercises appear at the end of mo

  20. Oxygen binding to partially nitrosylated hemoglobin.

    Science.gov (United States)

    Fago, Angela; Crumbliss, Alvin L; Hendrich, Michael P; Pearce, Linda L; Peterson, Jim; Henkens, Robert; Bonaventura, Celia

    2013-09-01

    Reactions of nitric oxide (NO) with hemoglobin (Hb) are important elements in protection against nitrosative damage. NO in the vasculature is depleted by the oxidative reaction with oxy Hb or by binding to deoxy Hb to generate partially nitrosylated Hb (Hb-NO). Many aspects of the formation and persistence of Hb-NO are yet to be clarified. In this study, we used a combination of EPR and visible absorption spectroscopy to investigate the interactions of partially nitrosylated Hb with O2. Partially nitrosylated Hb samples had predominantly hexacoordinate NO-heme geometry and resisted oxidation when exposed to O2 in the absence of anionic allosteric effectors. Faster oxidation occurred in the presence of 2,3-diphosphoglycerate (DPG) or inositol hexaphosphate (IHP), where the NO-heme derivatives had higher levels of pentacoordinate heme geometry. The anion-dependence of the NO-heme geometry also affected O2 binding equilibria. O2-binding curves of partially nitrosylated Hb in the absence of anions were left-shifted at low saturations, indicating destabilization of the low O2 affinity T-state of the Hb by increasing percentages of NO-heme, much as occurs with increasing levels of CO-heme. Samples containing IHP showed small decreases in O2 affinity, indicating shifts toward the low-affinity T-state and formation of inert α-NO/β-met tetramers. Most remarkably, O2-equilibria in the presence of the physiological effector DPG were essentially unchanged by up to 30% NO-heme in the samples. As will be discussed, under physiological conditions the interactions of Hb with NO provide protection against nitrosative damage without impairing O2 transport by Hb's unoccupied heme sites. This article is part of a Special Issue entitled: Oxygen Binding and Sensing Proteins. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Partial Conservation of Seniority and Nuclear Isomerism

    International Nuclear Information System (INIS)

    Van Isacker, P.; Heinze, S.

    2008-01-01

    We point out the possibility of the partial conservation of the seniority quantum number when most eigenstates are mixed in seniority but some remain pure. This situation occurs in nuclei for the g 9/2 and h 9/2 shells where it is at the origin of the existence of seniority isomers in the ruthenium and palladium isotopes. It also occurs for f bosons

  2. Telescopic Partial Dentures-Concealed Technology

    OpenAIRE

    Bhagat, Tushar Vitthalrao; Walke, Ashwini Nareshchandra

    2015-01-01

    The ideal goal of good dentist is to restore the missing part of oral structure, phonetics, his look and the most important is restored the normal health of the patient, which is hampered due to less or insufficient intake of food. Removable partial denture (RPD) treatment option is considered as a notion, which precludes the inevitability of ?floating plastic? in edentulous mouth, that many times fail to fulfill the above essential of the patients. In modern dentistry, though the dental impl...

  3. Some Considerations on the Partial Credit Model

    OpenAIRE

    H.H.F.M. Verstralen; N.D. Verhelst

    2008-01-01

    The Partial Credit Model (PCM) is sometimes interpreted as a model for stepwise solution of polytomously scored items, where the item parameters are interpreted as di culties of the steps. It is argued that this interpretation is not justi ed. A model for stepwise solution is discussed. It is shown that the PCM is suited to model sums of binary responses which are not supposed to be stochastically independent. As a practical result, a statistical test of sto...

  4. Response Styles in the Partial Credit Model

    OpenAIRE

    Tutz, Gerhard; Schauberger, Gunther; Berger, Moritz

    2016-01-01

    In the modelling of ordinal responses in psychological measurement and survey- based research, response styles that represent specific answering patterns of respondents are typically ignored. One consequence is that estimates of item parameters can be poor and considerably biased. The focus here is on the modelling of a tendency to extreme or middle categories. An extension of the Partial Credit Model is proposed that explicitly accounts for this specific response style. In contrast to exi...

  5. A computational formalization for partial evaluation

    DEFF Research Database (Denmark)

    Hatcliff, John; Danvy, Olivier

    1996-01-01

    We formalize a partial evaluator for Eugenio Moggi's computational metalanguage. This formalization gives an evaluation-order independent view of binding-time analysis and program specialization, including a proper treatment of call unfolding. It also enables us to express the essence of `control......-based binding-time improvements' for let expressions. Specically, we prove that the binding-time improvements given by `continuation-based specialization' can be expressed in the metalanguage via monadic laws....

  6. Energy considerations in the partial space elevator

    Science.gov (United States)

    Woo, Pamela; Misra, Arun K.

    2014-06-01

    The space elevator has been proposed as an alternate method for space transportation. A partial elevator is composed of a tether of several hundreds of kilometres, held vertically in tension between two end masses, with its centre of orbit placed at the geosynchronous orbit. A spacecraft can dock at the lower end, and then use the climber on the elevator to ascend to higher altitudes. In this paper, energy calculations are performed, to determine whether a partial elevator can provide sufficient savings in operational costs, compared to the traditional rocket-powered launch. The energy required to launch a spacecraft from a Low Earth Orbit (LEO) to the geostationary orbit (GEO) is calculated for two trajectories. In the first trajectory, the spacecraft travels from LEO to GEO via a Hohmann transfer. In the second trajectory, the spacecraft travels from LEO to the lower end of the partial space elevator with a Hohmann transfer, and then uses the elevator to climb to GEO. The total energy required is compared between the two trajectories. The effects of tether length, spacecraft-to-climber mass ratio, altitude of LEO, and tether material are investigated.

  7. Magnetic resonance imaging in complex partial seizures

    International Nuclear Information System (INIS)

    Furune, Sunao; Negoro, Tamiko; Maehara, Mitsuo; Nomura, Kazushi; Miura, Kiyokuni; Takahashi, Izumi; Watanabe, Kazuyoshi

    1989-01-01

    Magnetic resonance imaging (MRI) and computed tomography (CT) were performed on 45 patients with intractable complex partial seizures. MRI was performed with a superconducting whole-body scanner operating at 0.5 tesla (T) and 1.5 T. In patients with temporal lobe epilepsy, 8 of 24 patients had abnormal CT, but 16 or 24 patients showed abnormal MRI. 1.5 T MRI detected more abnormality than 0.5 T MRI when CT was normal. In patients with frontal lobe epilepsy, 5 of 7 patients had normal CT and MRI. In 2 other patients, MRI demonstrated an arachnoid cyst and increased signal intensity area on the T2-weighted images which were not detected by CT. In patients with occipital lobe epilepsy, 5 of 6 patients show abnormal CT and MRI. In patients with tuberous sclerosis, MRI revealed some increased signal intensity areas on the T2-weighted images in the occipital and temporal lobe, which were not detected by CT. Most surface EEG foci corresponded with the side of MRI abnormality. These data indicate that MRI is more informative than CT in complex partial seizures. MRI is the imaging technique of choice in the diagnosis of complex partial seizures. (author)

  8. Partially ordered sets in complex networks

    International Nuclear Information System (INIS)

    Xuan Qi; Du Fang; Wu Tiejun

    2010-01-01

    In this paper, a partial-order relation is defined among vertices of a network to describe which vertex is more important than another on its contribution to the connectivity of the network. A maximum linearly ordered subset of vertices is defined as a chain and the chains sharing the same end-vertex are grouped as a family. Through combining the same vertices appearing in different chains, a directed chain graph is obtained. Based on these definitions, a series of new network measurements, such as chain length distribution, family diversity distribution, as well as the centrality of families, are proposed. By studying the partially ordered sets in three kinds of real-world networks, many interesting results are revealed. For instance, the similar approximately power-law chain length distribution may be attributed to a chain-based positive feedback mechanism, i.e. new vertices prefer to participate in longer chains, which can be inferred by combining the notable preferential attachment rule with a well-ordered recommendation manner. Moreover, the relatively large average incoming degree of the chain graphs may indicate an efficient substitution mechanism in these networks. Most of the partially ordered set-based properties cannot be explained by the current well-known scale-free network models; therefore, we are required to propose more appropriate network models in the future.

  9. Partially massless higher-spin theory

    Energy Technology Data Exchange (ETDEWEB)

    Brust, Christopher [Perimeter Institute for Theoretical Physics,31 Caroline St. N, Waterloo, Ontario N2L 2Y5 (Canada); Hinterbichler, Kurt [CERCA, Department of Physics, Case Western Reserve University,10900 Euclid Ave, Cleveland, OH 44106 (United States)

    2017-02-16

    We study a generalization of the D-dimensional Vasiliev theory to include a tower of partially massless fields. This theory is obtained by replacing the usual higher-spin algebra of Killing tensors on (A)dS with a generalization that includes “third-order” Killing tensors. Gauging this algebra with the Vasiliev formalism leads to a fully non-linear theory which is expected to be UV complete, includes gravity, and can live on dS as well as AdS. The linearized spectrum includes three massive particles and an infinite tower of partially massless particles, in addition to the usual spectrum of particles present in the Vasiliev theory, in agreement with predictions from a putative dual CFT with the same symmetry algebra. We compute the masses of the particles which are not fixed by the massless or partially massless gauge symmetry, finding precise agreement with the CFT predictions. This involves computing several dozen of the lowest-lying terms in the expansion of the trilinear form of the enlarged higher-spin algebra. We also discuss nuances in the theory that occur in specific dimensions; in particular, the theory dramatically truncates in bulk dimensions D=3,5 and has non-diagonalizable mixings which occur in D=4,7.

  10. Partially massless higher-spin theory

    International Nuclear Information System (INIS)

    Brust, Christopher; Hinterbichler, Kurt

    2017-01-01

    We study a generalization of the D-dimensional Vasiliev theory to include a tower of partially massless fields. This theory is obtained by replacing the usual higher-spin algebra of Killing tensors on (A)dS with a generalization that includes “third-order” Killing tensors. Gauging this algebra with the Vasiliev formalism leads to a fully non-linear theory which is expected to be UV complete, includes gravity, and can live on dS as well as AdS. The linearized spectrum includes three massive particles and an infinite tower of partially massless particles, in addition to the usual spectrum of particles present in the Vasiliev theory, in agreement with predictions from a putative dual CFT with the same symmetry algebra. We compute the masses of the particles which are not fixed by the massless or partially massless gauge symmetry, finding precise agreement with the CFT predictions. This involves computing several dozen of the lowest-lying terms in the expansion of the trilinear form of the enlarged higher-spin algebra. We also discuss nuances in the theory that occur in specific dimensions; in particular, the theory dramatically truncates in bulk dimensions D=3,5 and has non-diagonalizable mixings which occur in D=4,7.

  11. Partial avascular necrosis after talar neck fracture.

    Science.gov (United States)

    Babu, Nina; Schuberth, John M

    2010-09-01

    Recently, it has been shown that avascular necrosis of the talus can occur in only a portion of the talar body. There is little information regarding the geographic location of the avascular segment and the clinical significance of an incomplete avascular process. Seven patients with partial avascular necrosis after Hawkins type II or III fracture dislocations were evaluated with magnetic resonance scans. The precise anatomic location of the avascular segment was determined and assigned to a specific quadrant of the talar body. The operative exposure, incidence of collapse, and time to operative intervention was recorded. The avascular segment of the talar body was located predominantly in the anterior lateral and superior portion in six of the seven patients. Collapse occurred in three of the patients in the area of avascular process. There were no observable trends with regard to operative exposure, Hawkins classification, incidence of collapse, or time to operative intervention to the location of the avascular segment. Partial avascular necrosis can occur after fracture dislocation of the talus. The predominant location of the avascular segment was the anterior lateral and superior portion of the talar body. This observation corresponds to regional damage to the blood supply of the talus and may help clarify the pathogenesis of partial avascular process.

  12. Development of coal partial hydropyrolysis process

    Energy Technology Data Exchange (ETDEWEB)

    Hideaki Yabe; Takafumi Kawamura; Kohichiroh Gotoh; Akemitsu Akimoto [Nippon Steel Corporation, Chiba (Japan)

    2005-07-01

    Coal partial hydropyrolysis process aims at co-production of high yield of light oil such as BTX and naphthalene and synthesis gas from a low rank coal under a mild hydropyrolysis condition. The characteristic of this process is in the two-staged entrained hydropyrolysis reactor composed of the reformer and gasifier. This reactor arrangement gives us high heat efficiency of this process. So far, in order to evaluate the process concept a small-scale basic experiment and a 1t/day process development unit study were carried out. The experimental results showed that coal volatiles were partially hydrogenated to increase the light oil and hydrocarbon gases at the condition of partial hydropyrolysis such as pressure of 2-3MPa, temperature of 700-900{sup o}C and hydrogen concentration of 30-50%. This process has a possibility of producing efficiently and economically liquid and gas products as chemicals and fuel for power generation. As a further development in the period of 2003 to 2008, a 20t/day pilot plant study named ECOPRO (efficient co-production with coal flash hydropyrolysis technology) has been started to establish the process technologies for commercialization. 12 refs., 6 figs., 3 tabs.

  13. Does partial occlusion promote normal binocular function?

    Science.gov (United States)

    Li, Jingrong; Thompson, Benjamin; Ding, Zhaofeng; Chan, Lily Y L; Chen, Xiang; Yu, Minbin; Deng, Daming; Hess, Robert F

    2012-10-03

    There is growing evidence that abnormal binocular interactions play a key role in the amblyopia syndrome and represent a viable target for treatment interventions. In this context the use of partial occlusion using optical devices such as Bangerter filters as an alternative to complete occlusion is of particular interest. The aims of this study were to understand why Bangerter filters do not result in improved binocular outcomes compared to complete occlusion, and to compare the effects of Bangerter filters, optical blur and neutral density (ND) filters on normal binocular function. The effects of four strengths of Bangerter filters (0.8, 0.6, 0.4, 0.2) on letter and vernier acuity, contrast sensitivity, stereoacuity, and interocular suppression were measured in 21 observers with normal vision. In a subset of 14 observers, the partial occlusion effects of Bangerter filters, ND filters and plus lenses on stereopsis and interocular suppression were compared. Bangerter filters did not have graded effect on vision and induced significant disruption to binocular function. This disruption was greater than that of monocular defocus but weaker than that of ND filters. The effect of the Bangerter filters on stereopsis was more pronounced than their effect on monocular acuity, and the induced monocular acuity deficits did not predict the induced deficits in stereopsis. Bangerter filters appear to be particularly disruptive to binocular function. Other interventions, such as optical defocus and those employing computer generated dichoptic stimulus presentation, may be more appropriate than partial occlusion for targeting binocular function during amblyopia treatment.

  14. Pseudo Boolean Programming for Partially Ordered Genomes

    Science.gov (United States)

    Angibaud, Sébastien; Fertin, Guillaume; Thévenin, Annelyse; Vialette, Stéphane

    Comparing genomes of different species is a crucial problem in comparative genomics. Different measures have been proposed to compare two genomes: number of common intervals, number of adjacencies, number of reversals, etc. These measures are classically used between two totally ordered genomes. However, genetic mapping techniques often give rise to different maps with some unordered genes. Starting from a partial order between genes of a genome, one method to find a total order consists in optimizing a given measure between a linear extension of this partial order and a given total order of a close and well-known genome. However, for most common measures, the problem turns out to be NP-hard. In this paper, we propose a (0,1)-linear programming approach to compute a linear extension of one genome that maximizes the number of common intervals (resp. the number of adjacencies) between this linear extension and a given total order. Next, we propose an algorithm to find linear extensions of two partial orders that maximize the number of adjacencies.

  15. Memoization in Type-Directed Partial Evaluation

    DEFF Research Database (Denmark)

    Balat, Vincent; Danvy, Olivier

    2002-01-01

    We use a code generator—type-directed partial evaluation— to verify conversions between isomorphic types, or more precisely to verify that a composite function is the identity function at some complicated type. A typed functional language such as ML provides a natural support to express the funct......We use a code generator—type-directed partial evaluation— to verify conversions between isomorphic types, or more precisely to verify that a composite function is the identity function at some complicated type. A typed functional language such as ML provides a natural support to express...... originate in the handling of sums, which uses delimited continuations. We successfully eliminate these redundancies by extending type-directed partial evaluation with memoization capabilities. The result only works for pure functional programs, but it provides an unexpected use of code generation...... and it yields orders-of-magnitude improvements both in time and in space for type isomorphisms. Basic Research in Computer Science (www. brics. dk), funded by the Danish National Research Foundation....

  16. Partial lesions of the intratemporal segment of the facial nerve: graft versus partial reconstruction.

    Science.gov (United States)

    Bento, Ricardo F; Salomone, Raquel; Brito, Rubens; Tsuji, Robinson K; Hausen, Mariana

    2008-09-01

    In cases of partial lesions of the intratemporal segment of the facial nerve, should the surgeon perform an intraoperative partial reconstruction, or partially remove the injured segment and place a graft? We present results from partial lesion reconstruction on the intratemporal segment of the facial nerve. A retrospective study on 42 patients who presented partial lesions on the intratemporal segment of the facial nerve was performed between 1988 and 2005. The patients were divided into 3 groups based on the procedure used: interposition of the partial graft on the injured area of the nerve (group 1; 12 patients); keeping the preserved part and performing tubulization (group 2; 8 patients); and dividing the parts of the injured nerve (proximal and distal) and placing a total graft of the sural nerve (group 3; 22 patients). Fracture of the temporal bone was the most frequent cause of the lesion in all groups, followed by iatrogenic causes (p lesion of the facial nerve is still questionable. Among these 42 patients, the best results were those from the total graft of the facial nerve.

  17. Distal splenorenal shunt with partial spleen resection

    Directory of Open Access Journals (Sweden)

    Gajin Predrag

    2007-01-01

    Full Text Available Introduction: Hypersplenism is a common complication of portal hypertension. Cytopenia in hypersplenism is predominantly caused by splenomegaly. Distal splenorenal shunt (Warren with partial spleen resection is an original surgical technique that regulates cytopenia by reduction of the enlarged spleen. Objective. The aim of our study was to present the advantages of distal splenorenal shunt (Warren with partial spleen resection comparing morbidity and mortality in a group of patients treated by distal splenorenal shunt with partial spleen resection with a group of patients treated only by a distal splenorenal shunt. Method. From 1995 to 2003, 41 patients with portal hypertension were surgically treated due to hypersplenism and oesophageal varices. The first group consisted of 20 patients (11 male, mean age 42.3 years who were treated by distal splenorenal shunt with partial spleen resection. The second group consisted of 21 patients (13 male, mean age 49.4 years that were treated by distal splenorenal shunt only. All patients underwent endoscopy and assessment of oesophageal varices. The size of the spleen was evaluated by ultrasound, CT or by scintigraphy. Angiography was performed in all patients. The platelet and white blood cell count and haemoglobin level were registered. Postoperatively, we noted blood transfusion, complications and total hospital stay. Follow-up period was 12 months, with first checkup after one month. Results In the first group, only one patient had splenomegaly postoperatively (5%, while in the second group there were 13 patients with splenomegaly (68%. Before surgery, the mean platelet count in the first group was 51.6±18.3x109/l, to 118.6±25.4x109/l postoperatively. The mean platelet count in the second group was 67.6±22.8x109/l, to 87.8±32.1x109/l postoperatively. Concerning postoperative splenomegaly, statistically significant difference was noted between the first and the second group (p<0.05. Comparing the

  18. Partial axillary dissection in early breast cancer

    Directory of Open Access Journals (Sweden)

    Tarek Abdel Halim El-Fayoumi

    2013-09-01

    Full Text Available Background: In order to reduce the probability of later clinical involvement of the axilla and at establishing a sound basis for adjuvant treatment planning axillary dissection is an important operative procedure. So, partial axillary dissection has been applied to decrease the morbidity and postoperative axillary complications.Aim of the work was to study the reliability of partial axillary lymph node dissection in patients with breast carcinoma with clinically negative axilla. Methods: Eighteen patients underwent modified radical mastectomy, while the other two patients who were fulfilling the criteria for conservative breast surgery underwent lumpectomy. All patients did complete axillary lymph nodes dissection. Intraoperative leveling of the axilla was performed and level I axillary lymph nodes were identified according to their relation to pectoralis minor muscle; then they were subjected to intraoperative pathological examination by frozen section examination followed by complete axillary clearance. Then post operative histopathological examination of the tumor and all lymph nodes was done. Results: By intraoperative pathological examination; five patients (25% were found positive for malignant invasion, while 15 patients (75% were pathologically free. While paraffin section showed six patients (30% with malignant invasion, and 14 patients (70% were pathologically free. There was a false negative rate of 5% in level I axillary lymph nodes by intraoperative pathological examination which was positive for metastasis by paraffin section that revealed microinvasion in one lymph node out of 8 in level I. Only two cases out of 20 were found positive for metastasis in level II and III. Conclusion: Partial axillary lymph node dissection is a minimally invasive, feasible and sufficient technique that can predict the axillary lymph node status. KEYWORDS: Breast cancer, Axillary lymph nodes clearance

  19. Gravity Effects Observed In Partially Premixed Flames

    Science.gov (United States)

    Puri, Ishwar K.; Aggarwal, Suresh K.; Lock, Andrew J.; Gauguly, Ranjan; Hegde, Uday

    2003-01-01

    Partially premixed flames (PPFs) contain a rich premixed fuel air mixture in a pocket or stream, and, for complete combustion to occur, they require the transport of oxidizer from an appropriately oxidizer-rich (or fuel-lean) mixture that is present in another pocket or stream. Partial oxidation reactions occur in fuel-rich portions of the mixture and any remaining unburned fuel and/or intermediate species are consumed in the oxidizer-rich portions. Partial premixing, therefore, represents that condition when the equivalence ratio (phi) in one portion of the flowfield is greater than unity, and in another section its value is less than unity. In general, for combustion to occur efficiently, the global equivalence ratio is in the range fuel-lean to stoichiometric. These flames can be established by design by placing a fuel-rich mixture in contact with a fuel-lean mixture, but they also occur otherwise in many practical systems, which include nonpremixed lifted flames, turbulent nonpremixed combustion, spray flames, and unwanted fires. Other practical applications of PPFs are reported elsewhere. Although extensive experimental studies have been conducted on premixed and nonpremixed flames under microgravity, there is a absence of previous experimental work on burner stabilized PPFs in this regard. Previous numerical studies by our group employing a detailed numerical model showed gravity effects to be significant on the PPF structure. We report on the results of microgravity experiments conducted on two-dimensional (established on a Wolfhard-Parker slot burner) and axisymmetric flames (on a coannular burner) that were investigated in a self-contained multipurpose rig. Thermocouple and radiometer data were also used to characterize the thermal transport in the flame.

  20. [Partial replantation following proximal limb injury].

    Science.gov (United States)

    Dubert, T; Malikov, S A; Dinh, A; Kupatadze, D D; Oberlin, C; Alnot, J Y; Nabokov, B B

    2000-11-01

    Proximal replantation is a technically feasible but life-threatening procedure. Indications must be restricted to patients in good condition with a good functional prognosis. The goal of replantation must be focused not only on reimplanting the amputated limb but also on achieving a good functional outcome. For the lower limb, simple terminalization remains the best choice in many cases. When a proximal amputation is not suitable for replantation, the main aim of the surgical procedure must be to reconstruct a stump long enough to permit fitting a prosthesis preserving the function of the adjacent joint. If the proximal stump beyond the last joint is very short, it may be possible to restore some length by partial replantation of spared tissues from the amputated part. We present here the results we obtained following this policy. This series included 16 cases of partial replantations, 14 involving the lower limb and 2 the upper limb. All were osteocutaneous microsurgical transfers. For the lower limb, all transfers recovered protective sensitivity following tibial nerve repair. The functional calcaeoplantar unit was used in 13 cases. The transfer of this specialized weight bearing tissue provided a stable distal surface making higher support unnecessary. In one case, we raised a 13-cm vascularized tibial segment covered with foot skin for additional length. For the upper limb, the osteocutaneous transfer, based on the radial artery, was not reinnervated, but this lack of sensitivity did not impair prosthesis fitting. One vascular failure was finally amputated. This was the only unsuccessful result. For all other patients, the surgical procedure facilitated prosthesis fitting and preserved the proximal joint function despite an initially very proximal amputation. The advantages of partial replantation are obvious compared with simple terminalization or secondary reconstruction. There is no secondary donor site and, because there is no major muscle mass in the

  1. Nonlinear partial differential equations of second order

    CERN Document Server

    Dong, Guangchang

    1991-01-01

    This book addresses a class of equations central to many areas of mathematics and its applications. Although there is no routine way of solving nonlinear partial differential equations, effective approaches that apply to a wide variety of problems are available. This book addresses a general approach that consists of the following: Choose an appropriate function space, define a family of mappings, prove this family has a fixed point, and study various properties of the solution. The author emphasizes the derivation of various estimates, including a priori estimates. By focusing on a particular approach that has proven useful in solving a broad range of equations, this book makes a useful contribution to the literature.

  2. A partial differential equation for pseudocontact shift.

    Science.gov (United States)

    Charnock, G T P; Kuprov, Ilya

    2014-10-07

    It is demonstrated that pseudocontact shift (PCS), viewed as a scalar or a tensor field in three dimensions, obeys an elliptic partial differential equation with a source term that depends on the Hessian of the unpaired electron probability density. The equation enables straightforward PCS prediction and analysis in systems with delocalized unpaired electrons, particularly for the nuclei located in their immediate vicinity. It is also shown that the probability density of the unpaired electron may be extracted, using a regularization procedure, from PCS data.

  3. Computational partial differential equations using Matlab

    CERN Document Server

    Li, Jichun

    2008-01-01

    Brief Overview of Partial Differential Equations The parabolic equations The wave equations The elliptic equations Differential equations in broader areasA quick review of numerical methods for PDEsFinite Difference Methods for Parabolic Equations Introduction Theoretical issues: stability, consistence, and convergence 1-D parabolic equations2-D and 3-D parabolic equationsNumerical examples with MATLAB codesFinite Difference Methods for Hyperbolic Equations IntroductionSome basic difference schemes Dissipation and dispersion errors Extensions to conservation lawsThe second-order hyperbolic PDE

  4. Nonlinear elliptic partial differential equations an introduction

    CERN Document Server

    Le Dret, Hervé

    2018-01-01

    This textbook presents the essential parts of the modern theory of nonlinear partial differential equations, including the calculus of variations. After a short review of results in real and functional analysis, the author introduces the main mathematical techniques for solving both semilinear and quasilinear elliptic PDEs, and the associated boundary value problems. Key topics include infinite dimensional fixed point methods, the Galerkin method, the maximum principle, elliptic regularity, and the calculus of variations. Aimed at graduate students and researchers, this textbook contains numerous examples and exercises and provides several comments and suggestions for further study.

  5. Crowdfunding Through a Partial Organizational Lens

    DEFF Research Database (Denmark)

    Roed Nielsen, Kristian

    -professional investors to support their preferred project(s). However, while the phenomenon continues to grow rapidly our academic knowledge of this emergent organizational form has lagged behind. The literature to date remains largely ‘phenomenon-driven’ where definitions and descriptions are typically delimited...... types, where complete and partial organisations do not emerge as separate entities each filling their own presupposed role, but do so co-dependently which consequently allow for a fluid, but also entangled organizational structure. The paper finally argues that crowdfunding literature merits greater...

  6. Partial muscle carnitine palmitoyltransferase-A deficiency

    International Nuclear Information System (INIS)

    Ross, N.S.; Hoppel, C.L.

    1987-01-01

    After initiation of ibuprofen therapy, a 45-year-old woman developed muscle weakness and tenderness with rhabdomyolysis, culminating in respiratory failure. A muscle biopsy specimen showed a vacuolar myopathy, and markedly decreased muscle carnitine content and carnitine palmitoyltransferase activity. Following recovery, muscle carnitine content was normal but carnitine palmitoyltransferase activity was still abnormally low. The ratio of palmitoyl-coenzyme A plus carnitine to palmitoylcarnitine oxidation by muscle mitochondria isolated from the patient was markedly decreased. The authors conclude that transiently decreased muscle carnitine content interacted with partial deficiency of carnitine palmitoyltransferase-A to produce rhabdomyolysis and respiratory failure and that ibuprofen may have precipitated the clinical event

  7. Partial differential equation models in macroeconomics.

    Science.gov (United States)

    Achdou, Yves; Buera, Francisco J; Lasry, Jean-Michel; Lions, Pierre-Louis; Moll, Benjamin

    2014-11-13

    The purpose of this article is to get mathematicians interested in studying a number of partial differential equations (PDEs) that naturally arise in macroeconomics. These PDEs come from models designed to study some of the most important questions in economics. At the same time, they are highly interesting for mathematicians because their structure is often quite difficult. We present a number of examples of such PDEs, discuss what is known about their properties, and list some open questions for future research. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  8. On construction of partial association rules

    KAUST Repository

    Moshkov, Mikhail

    2009-01-01

    This paper is devoted to the study of approximate algorithms for minimization of partial association rule length. It is shown that under some natural assumptions on the class NP, a greedy algorithm is close to the best polynomial approximate algorithms for solving of this NP-hard problem. The paper contains various bounds on precision of the greedy algorithm, bounds on minimal length of rules based on an information obtained during greedy algorithm work, and results of the study of association rules for the most part of binary information systems. © 2009 Springer Berlin Heidelberg.

  9. Boundary value problems and partial differential equations

    CERN Document Server

    Powers, David L

    2005-01-01

    Boundary Value Problems is the leading text on boundary value problems and Fourier series. The author, David Powers, (Clarkson) has written a thorough, theoretical overview of solving boundary value problems involving partial differential equations by the methods of separation of variables. Professors and students agree that the author is a master at creating linear problems that adroitly illustrate the techniques of separation of variables used to solve science and engineering.* CD with animations and graphics of solutions, additional exercises and chapter review questions* Nearly 900 exercises ranging in difficulty* Many fully worked examples

  10. Nonlinear partial differential equations and their applications

    CERN Document Server

    Lions, Jacques Louis

    2002-01-01

    This book contains the written versions of lectures delivered since 1997 in the well-known weekly seminar on Applied Mathematics at the Collège de France in Paris, directed by Jacques-Louis Lions. It is the 14th and last of the series, due to the recent and untimely death of Professor Lions. The texts in this volume deal mostly with various aspects of the theory of nonlinear partial differential equations. They present both theoretical and applied results in many fields of growing importance such as Calculus of variations and optimal control, optimization, system theory and control, op

  11. Partial differential equations and their applications

    International Nuclear Information System (INIS)

    Gauthier-Villars

    1998-01-01

    This book is dedicated to the French mathematician J.L.Lions. It represents a compilation of articles from about 80 authors. The topics treated are diverse but the more or less commune matter is the study of the characteristics of some partial differential equations. Stability, optimal approximation, numerical resolution, particular applications are among the subjects reviewed. An article deals with the MHD stability of fusion plasmas in tokamaks, another presents the scientific and technical challenges of nuclear energy in France. The latter that contains no equations can be considered as an enjoyable break in a sea of about 40 mathematical articles. (A.C.)

  12. Turbo Equalization Using Partial Gaussian Approximation

    DEFF Research Database (Denmark)

    Zhang, Chuanzong; Wang, Zhongyong; Manchón, Carles Navarro

    2016-01-01

    This letter deals with turbo equalization for coded data transmission over intersymbol interference (ISI) channels. We propose a message-passing algorithm that uses the expectation propagation rule to convert messages passed from the demodulator and decoder to the equalizer and computes messages...... returned by the equalizer by using a partial Gaussian approximation (PGA). We exploit the specific structure of the ISI channel model to compute the latter messages from the beliefs obtained using a Kalman smoother/equalizer. Doing so leads to a significant complexity reduction compared to the initial PGA...

  13. Testing the generalized partial credit model

    OpenAIRE

    Glas, Cornelis A.W.

    1996-01-01

    The partial credit model (PCM) (G.N. Masters, 1982) can be viewed as a generalization of the Rasch model for dichotomous items to the case of polytomous items. In many cases, the PCM is too restrictive to fit the data. Several generalizations of the PCM have been proposed. In this paper, a generalization of the PCM (GPCM), a further generalization of the one-parameter logistic model, is discussed. The model is defined and the conditional maximum likelihood procedure for the method is describe...

  14. Some Considerations on the Partial Credit Model

    Directory of Open Access Journals (Sweden)

    H.H.F.M. Verstralen

    2008-01-01

    Full Text Available The Partial Credit Model (PCM is sometimes interpreted as a model for stepwise solution of polytomously scored items, where the item parameters are interpreted as di culties of the steps. It is argued that this interpretation is not justi ed. A model for stepwise solution is discussed. It is shown that the PCM is suited to model sums of binary responses which are not supposed to be stochastically independent. As a practical result, a statistical test of stochastic independence in the Rasch model is derived

  15. The Partial Mapping of the Web Graph

    Directory of Open Access Journals (Sweden)

    Kristina Machova

    2009-06-01

    Full Text Available The paper presents an approach to partial mapping of a web sub-graph. This sub-graph contains the nearest surroundings of an actual web page. Our work deals with acquiring relevant Hyperlinks of a base web site, generation of adjacency matrix, the nearest distance matrix and matrix of converted distances of Hyperlinks, detection of compactness of web representation, and visualization of its graphical representation. The paper introduces an LWP algorithm – a technique for Hyperlink filtration.  This work attempts to help users with the orientation within the web graph.

  16. Partial muscle carnitine palmitoyltransferase-A deficiency

    Energy Technology Data Exchange (ETDEWEB)

    Ross, N.S.; Hoppel, C.L.

    1987-01-02

    After initiation of ibuprofen therapy, a 45-year-old woman developed muscle weakness and tenderness with rhabdomyolysis, culminating in respiratory failure. A muscle biopsy specimen showed a vacuolar myopathy, and markedly decreased muscle carnitine content and carnitine palmitoyltransferase activity. Following recovery, muscle carnitine content was normal but carnitine palmitoyltransferase activity was still abnormally low. The ratio of palmitoyl-coenzyme A plus carnitine to palmitoylcarnitine oxidation by muscle mitochondria isolated from the patient was markedly decreased. The authors conclude that transiently decreased muscle carnitine content interacted with partial deficiency of carnitine palmitoyltransferase-A to produce rhabdomyolysis and respiratory failure and that ibuprofen may have precipitated the clinical event.

  17. Partial solvation parameters and LSER molecular descriptors

    International Nuclear Information System (INIS)

    Panayiotou, Costas

    2012-01-01

    Graphical abstract: The one-to-one correspondence of LSER molecular descriptors and partial solvation parameters (PSPs) for propionic acid. Highlights: ► Quantum-mechanics based development of a new QSPR predictive method. ► One-to-one correspondence of partial solvation parameters and LSER molecular descriptors. ► Development of alternative routes for the determination of partial solvation parameters and solubility parameters. ► Expansion and enhancement of solubility parameter approach. - Abstract: The partial solvation parameters (PSP) have been defined recently, on the basis of the insight derived from modern quantum chemical calculations, in an effort to overcome some of the inherent restrictions of the original definition of solubility parameter and expand its range of applications. The present work continues along these lines and introduces two new solvation parameters, the van der Waals and the polarity/refractivity ones, which may replace both of the former dispersion and polar PSPs. Thus, one may use either the former scheme of PSPs (dispersion, polar, acidic, and basic) or, equivalently, the new scheme (van der Waals, polarity/refractivity, acidic, basic). The new definitions are made in a simple and straightforward manner and, thus, the strength and appeal of the widely accepted concept of solubility parameter is preserved. The inter-relations of the various PSPs are critically discussed and their values are tabulated for a variety of common substances. The advantage of the new scheme of PSPs is the bridge that makes with the corresponding Abraham’s LSER descriptors. With this bridge, one may exchange information between PSPs, LSER experimental scales, and quantum mechanics calculations such as via the COSMO-RS theory. The proposed scheme is a predictive one and it is applicable to, both, homo-solvated and hetero-solvated compounds. The new scheme is tested for the calculation of activity coefficients at infinite dilution, for octanol

  18. ERC Workshop on Geometric Partial Differential Equations

    CERN Document Server

    Novaga, Matteo; Valdinoci, Enrico

    2013-01-01

    This book is the outcome of a conference held at the Centro De Giorgi of the Scuola Normale of Pisa in September 2012. The aim of the conference was to discuss recent results on nonlinear partial differential equations, and more specifically geometric evolutions and reaction-diffusion equations. Particular attention was paid to self-similar solutions, such as solitons and travelling waves, asymptotic behaviour, formation of singularities and qualitative properties of solutions. These problems arise in many models from Physics, Biology, Image Processing and Applied Mathematics in general, and have attracted a lot of attention in recent years.

  19. Numerical Methods for Partial Differential Equations

    CERN Document Server

    Guo, Ben-yu

    1987-01-01

    These Proceedings of the first Chinese Conference on Numerical Methods for Partial Differential Equations covers topics such as difference methods, finite element methods, spectral methods, splitting methods, parallel algorithm etc., their theoretical foundation and applications to engineering. Numerical methods both for boundary value problems of elliptic equations and for initial-boundary value problems of evolution equations, such as hyperbolic systems and parabolic equations, are involved. The 16 papers of this volume present recent or new unpublished results and provide a good overview of current research being done in this field in China.

  20. Economical analysis of the second partial reload for Angra 1 with partial low-leakage

    International Nuclear Information System (INIS)

    Mascarenhas, H.A.; Teixeira, M.C.C.; Dias, A.M.

    1990-01-01

    Preliminary results for the Angra 1 second reload design with partial low-leakage were assessed with NUCOST 1.0, code for nuclear power costs calculation. In the proposed scheme, some partially burned fuel assemblies (FAs) are located at the core boundary, while new FAs occupy more internal positions. The nuclear design - utilizing the code system SAV (from Siemens/KWU Group, F.R. Germany) - has been performed with detail for the 3rd cycle while simpler approach has been utilized for subsequent reloads. Results of NUCOST 1.0 show that the partial low-leakage reload in the 3rd cycle of Angra 1 offers fuel costs 1% lower when compared to the Plant's actual reload scheme, what corresponds to an savings of about US$190.000. When operation and maintenance and capital costs are also considered, economies in the order of US$2.6 million are obrained. (author) [pt

  1. Superconformal partial waves in Grassmannian field theories

    Energy Technology Data Exchange (ETDEWEB)

    Doobary, Reza; Heslop, Paul [Department of Mathematical Sciences, Durham University,South Road, Durham, DH1 3LE United Kingdom (United Kingdom)

    2015-12-23

    We derive superconformal partial waves for all scalar four-point functions on a super Grassmannian space Gr(m|n,2m|2n) for all m,n. This family of four-point functions includes those of all (arbitrary weight) half BPS operators in both N=4 SYM (m=n=2) and in N=2 superconformal field theories in four dimensions (m=2,n=1) on analytic superspace. It also includes four-point functions of all (arbitrary dimension) scalar fields in non-supersymmetric conformal field theories (m=2,n=0) on Minkowski space, as well as those of a certain class of representations of the compact SU(2n) coset spaces. As an application we then specialise to N=4 SYM and use these results to perform a detailed superconformal partial wave analysis of the four-point functions of arbitrary weight half BPS operators. We discuss the non-trivial separation of protected and unprotected sectors for the 〈2222〉, 〈2233〉 and 〈3333〉 cases in an SU(N) gauge theory at finite N. The 〈2233〉 correlator predicts a non-trivial protected twist four sector for 〈3333〉 which we can completely determine using the knowledge that there is precisely one such protected twist four operator for each spin.

  2. Decaying states as physically nonisolable partial systems

    International Nuclear Information System (INIS)

    Szasz, G.I.

    1976-01-01

    Presently the investigations of decaying quantum mechanical systems lack a well-founded concept, which is reflected by several formal difficulties of the corresponding mathematical treatment. In order to clarify in some respect the situation, it is investigated, within the framework of nonrelativistic quantum mechanics, the resonant scattering of an initially well localized partial wave packet. If the potential decreases sufficiently fast for r→infinite, the wave packet can be expressed at sufficiently long time after the scattering has taken place, as the sum of a term describing the direct scattering and a function of the resonant solution with complex 'momentum'. From such a heuristic relation one can deduce not only the probability for the creation of unstable particles but also obtain some hints to a connection between decaying states and physically nonisolable partial systems. On the other hand, this connection can perhaps display the inadequacy of attempts which suggest to solve the problem of decaying states within the usual Hilbert space methods. (author)

  3. Diffusion tensor imaging of partial intractable epilepsy

    International Nuclear Information System (INIS)

    Dumas de la Roque, Anne; Oppenheim, Catherine; Rodrigo, Sebastian; Meder, Jean-Francois; Chassoux, Francine; Devaux, Bertrand; Beuvon, Frederic; Daumas-Duport, Catherine

    2005-01-01

    Our aim was to assess the value of diffusion tensor imaging (DTI) in patients with partial intractable epilepsy. We used DTI (25 non-collinear directions) in 15 patients with a cortical lesion on conventional MRI. Fractional anisotropy (FA) was measured in the internal capsule, and in the normal-appearing white matter (WM), adjacent tothe lesion, and away from the lesion, at a set distance of 2-3 cm. In each patient, increased or decreased FA measurements were those that varied from mirror values using an arbitrary 10% threshold. Over the whole population, ipsi- and contralateral FA measurements were also compared using a Wilcoxon test (p<0.05). Over the whole population, FA was significantly reduced in the WM adjacent to and away from the lesion, whilst being normal in the internal capsule. FA was reduced by more than 10% in the WM adjacent to and distant from the lesion in 13 and 12 patients respectively. For nine of the ten patients for whom the surgical resection encompassed the limits of the lesion on conventional MRI, histological data showed WM alterations (gliosis, axonal loss, abnormal cells). DTI often reveals WM abnormalities that are undetected on conventional MRI in patients with partial intractable epilepsy. (orig.)

  4. Partial Facetectomy for Lumbar Foraminal Stenosis

    Directory of Open Access Journals (Sweden)

    Kevin Kang

    2014-01-01

    Full Text Available Background. Several different techniques exist to address the pain and disability caused by isolated nerve root impingement. Failure to adequately decompress the lumbar foramen may lead to failed back surgery syndrome. However, aggressive treatment often causes spinal instability or may require fusion for satisfactory results. We describe a novel technique for decompression of the lumbar nerve root and demonstrate its effectiveness in relief of radicular symptoms. Methods. Partial facetectomy was performed by removal of the medial portion of the superior facet in patients with lumbar foraminal stenosis. 47 patients underwent the procedure from 2001 to 2010. Those who demonstrated neurogenic claudication without spinal instability or central canal stenosis and failed conservative management were eligible for the procedure. Functional level was recorded for each patient. These patients were followed for an average of 3.9 years to evaluate outcomes. Results. 27 of 47 patients (57% reported no back pain and no functional limitations. Eight of 47 patients (17% reported moderate pain, but had no limitations. Six of 47 patients (13% continued to experience degenerative symptoms. Five of 47 patients (11% required additional surgery. Conclusions. Partial facetectomy is an effective means to decompress the lumbar nerve root foramen without causing spinal instability.

  5. Succinct partial sums and fenwick trees

    DEFF Research Database (Denmark)

    Bille, Philip; Christiansen, Anders Roy; Prezza, Nicola

    2017-01-01

    We consider the well-studied partial sums problem in succint space where one is to maintain an array of n k-bit integers subject to updates such that partial sums queries can be efficiently answered. We present two succint versions of the Fenwick Tree – which is known for its simplicity...... and practicality. Our results hold in the encoding model where one is allowed to reuse the space from the input data. Our main result is the first that only requires nk + o(n) bits of space while still supporting sum/update in O(logbn)/O(blogbn) time where 2 ≤ b ≤ log O(1)n. The second result shows how optimal...... time for sum/update can be achieved while only slightly increasing the space usage to nk + o(nk) bits. Beyond Fenwick Trees, the results are primarily based on bit-packing and sampling – making them very practical – and they also allow for simple optimal parallelization....

  6. Early structure of LPG partially premixed conically stabilized flames

    KAUST Repository

    Elbaz, Ayman M.

    2013-01-01

    This paper presents experimental investigation of LPG partially premixed turbulent flames stabilized within a conical nozzle burner under constant degree of partial premixing. The stability limits and mean flame structure are presented based

  7. Partial Orders and Fully Abstract Models for Concurrency

    DEFF Research Database (Denmark)

    Engberg, Uffe Henrik

    1990-01-01

    In this thesis sets of labelled partial orders are employed as fundamental mathematical entities for modelling nondeterministic and concurrent processes thereby obtaining so-called noninterleaving semantics. Based on different closures of sets of labelled partial orders, simple algebraic language...

  8. Partial separability and entanglement criteria for multiqubit quantum states

    NARCIS (Netherlands)

    Seevinck, M.P.; Uffink, J.B.M.

    2008-01-01

    We explore the subtle relationships between partial separability and entanglement of subsystems in multiqubit quantum states and give experimentally accessible conditions that distinguish between various classes and levels of partial separability in a hierarchical order. These conditions take the

  9. Linear algebraic theory of partial coherence: discrete fields and measures of partial coherence.

    Science.gov (United States)

    Ozaktas, Haldun M; Yüksel, Serdar; Kutay, M Alper

    2002-08-01

    A linear algebraic theory of partial coherence is presented that allows precise mathematical definitions of concepts such as coherence and incoherence. This not only provides new perspectives and insights but also allows us to employ the conceptual and algebraic tools of linear algebra in applications. We define several scalar measures of the degree of partial coherence of an optical field that are zero for full incoherence and unity for full coherence. The mathematical definitions are related to our physical understanding of the corresponding concepts by considering them in the context of Young's experiment.

  10. Partial Synchronization Manifolds for Linearly Time-Delay Coupled Systems

    OpenAIRE

    Steur, Erik; van Leeuwen, Cees; Michiels, Wim

    2014-01-01

    Sometimes a network of dynamical systems shows a form of incomplete synchronization characterized by synchronization of some but not all of its systems. This type of incomplete synchronization is called partial synchronization. Partial synchronization is associated with the existence of partial synchronization manifolds, which are linear invariant subspaces of C, the state space of the network of systems. We focus on partial synchronization manifolds in networks of system...

  11. Functional characterization of the spf/ash splicing variation in OTC deficiency of mice and man.

    Directory of Open Access Journals (Sweden)

    Ana Rivera-Barahona

    Full Text Available The spf/ash mouse model of ornithine transcarbamylase (OTC deficiency, a severe urea cycle disorder, is caused by a mutation (c.386G>A; p.R129H in the last nucleotide of exon 4 of the Otc gene, affecting the 5' splice site and resulting in partial use of a cryptic splice site 48 bp into the adjacent intron. The equivalent nucleotide change and predicted amino acid change is found in OTC deficient patients. Here we have used liver tissue and minigene assays to dissect the transcriptional profile resulting from the "spf/ash" mutation in mice and man. For the mutant mouse, we confirmed liver transcripts corresponding to partial intron 4 retention by the use of the c.386+48 cryptic site and to normally spliced transcripts, with exon 4 always containing the c.386G>A (p.R129H variant. In contrast, the OTC patient exhibited exon 4 skipping or c.386G>A (p.R129H-variant exon 4 retention by using the natural or a cryptic splice site at nucleotide position c.386+4. The corresponding OTC tissue enzyme activities were between 3-6% of normal control in mouse and human liver. The use of the cryptic splice sites was reproduced in minigenes carrying murine or human mutant sequences. Some normally spliced transcripts could be detected in minigenes in both cases. Antisense oligonucleotides designed to block the murine cryptic +48 site were used in minigenes in an attempt to redirect splicing to the natural site. The results highlight the relevance of in depth investigations of the molecular mechanisms of splicing mutations and potential therapeutic approaches. Notably, they emphasize the fact that findings in animal models may not be applicable for human patients due to the different genomic context of the mutations.

  12. Partial synchronization and spontaneous spatial ordering in coupled chaotic systems

    International Nuclear Information System (INIS)

    Ying Zhang; Gang Hu; Cerdeira, Hilda A.; Shigang Chen; Braun, Thomas; Yugui Yao

    2000-11-01

    A model of many symmetrically and locally coupled chaotic oscillators is studied. Partial chaotic synchronizations associated with spontaneous spatial ordering are demonstrated. Very rich patterns of the system are revealed, based on partial synchronization analysis. The stabilities of different partially synchronous spatiotemporal structures and some novel dynamical behaviors of these states are discussed both numerically and analytically. (author)

  13. Thin film devices used as oxygen partial pressure sensors

    Science.gov (United States)

    Canady, K. S.; Wortman, J. J.

    1970-01-01

    Electrical conductivity of zinc oxide films to be used in an oxygen partial pressure sensor is measured as a function of temperature, oxygen partial pressure, and other atmospheric constituents. Time response following partial pressure changes is studied as a function of temperature and environmental changes.

  14. Complex partial seizure, disruptive behaviours and the Nigerian ...

    African Journals Online (AJOL)

    Background: Complex partial seizure is an epileptic seizure which results in impairment of responsiveness or awareness such as altered level of consciousness. Complex partial seizures are often preceded by an aura such as depersonalization, feelings of de javu, jamais vu and fear. The ictal phase of complex partial ...

  15. 76 FR 55842 - Partial Approval and Partial Disapproval of Air Quality Implementation Plans; California; San...

    Science.gov (United States)

    2011-09-09

    ...; Reasonably Available Control Technology for Ozone AGENCY: Environmental Protection Agency (EPA). ACTION... CFR Part 52 Environmental protection, Air pollution control, Intergovernmental relations, Nitrogen... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 [EPA-R09-OAR-2011-0723; FRL-9462-3] Partial...

  16. On the relation between elementary partial difference equations and partial differential equations

    NARCIS (Netherlands)

    van den Berg, I.P.

    1998-01-01

    The nonstandard stroboscopy method links discrete-time ordinary difference equations of first-order and continuous-time, ordinary differential equations of first order. We extend this method to the second order, and also to an elementary, yet general class of partial difference/differential

  17. Theory on a partially ionized gas centrifuge

    International Nuclear Information System (INIS)

    Berg, M.S. van den.

    1982-01-01

    This thesis contains a study of some flow processes occurring in the Gaswhirl experiments. In this apparatus a partially ionized gas is forced into rotation by an azimuthal electromagnetic force. After a short introduction in which a motivation is given of our research project, a comprehensive treatment is presented of the principle of rotating plasmas. Further, a historical review is given of rotating plasma systems. A derivation of the fundamental equations is given which describe the flow system mathematically and these are applied to rotating plasmas. The occurrence of secondary flows with radial and axial components is considered. This qualitative picture of secondary whirls is confirmed by measurements reported in the next chapter. The last chapter offers a possible explanation of the occurrence of the transition process in the Gaswhirl apparatus. (Auth.)

  18. Coding with partially hidden Markov models

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Rissanen, J.

    1995-01-01

    Partially hidden Markov models (PHMM) are introduced. They are a variation of the hidden Markov models (HMM) combining the power of explicit conditioning on past observations and the power of using hidden states. (P)HMM may be combined with arithmetic coding for lossless data compression. A general...... 2-part coding scheme for given model order but unknown parameters based on PHMM is presented. A forward-backward reestimation of parameters with a redefined backward variable is given for these models and used for estimating the unknown parameters. Proof of convergence of this reestimation is given....... The PHMM structure and the conditions of the convergence proof allows for application of the PHMM to image coding. Relations between the PHMM and hidden Markov models (HMM) are treated. Results of coding bi-level images with the PHMM coding scheme is given. The results indicate that the PHMM can adapt...

  19. Partial pressure measurements with an active spectrometer

    International Nuclear Information System (INIS)

    Brooks, N.H.; Jensen, T.H.; Colchin, R.J.; Maingi, R.; Wade, M.R.; Finkenthal, D.F.; Naumenko, N.; Tugarinov, S.

    1998-07-01

    Partial pressure neutral ga measurements have been made using a commercial Penning gauge in conjunction with an active spectrometer. In prior work utilizing bandpass filters and conventional spectrometers, trace concentrations of the hydrogen isotopes H, D, T and of the noble gases He, Ne and Ar were determined from characteristic spectral lines in the light emitted by the neutral species of these elements. For all the elements mentioned, the sensitivity was limited by spectral contamination from a pervasive background of molecular hydrogen radiation. The active spectrometer overcomes this limitations by means of a digital lock-in method and correlation with reference spectra. Preliminary measurements of an admixture containing a trace amount of neon in deuterium show better than a factor of 20 improvement in sensitivity over conventional techniques. This can be further improved by correlating the relative intensities of multiple lines to sets of reference spectra

  20. Partial quantization of Lagrangian-Hamiltonian systems

    International Nuclear Information System (INIS)

    Amaral, C.M. do; Soares Filho, P.C.

    1979-05-01

    A classical variational principle is constructed in the Weiss form, for dynamical systems with support spaces of the configuration-phase kind. This extended principle rules the dynamics of classical systems, partially Hamiltonian, in interaction with Lagrangean parameterized subsidiary dynamics. The variational family of equations obtained, consists of an equation of the Hamilton-Jacobi type, coupled to a family of differential equations of the Euler-Lagrange form. The basic dynamical function appearing in the equations is a function of the Routh kind. By means of an ansatz induced by the variationally obtained family, a generalized set of equation, is proposed constituted by a wave equation of Schroedinger type, coupled to a family of equations formaly analog to those Euler-Lagrange equations. A basic operator of Routh type appears in our generalized set of equations. This operator describes the interaction between a quantized Hamiltonian dynamics, with a parameterized classical Lagrangean dynamics in semi-classical closed models. (author) [pt

  1. Two R curves for partially stabilized zirconia

    International Nuclear Information System (INIS)

    Rose, L.R.F.; Swain, M.V.

    1986-01-01

    The enhanced fracture toughness due to stress-induced transformation can be explained from two view points: (1) the increase can be attributed to the need to supply a work of transformation, or (2) the transformation can be considered to result in internal stresses which oppose crack opening. Experimental results for magnesia-partially-stabilized zirconia are presented for the two experimental measures of toughness corresponding to these two viewpoints, namely (1) the specific work of fracture, R, and (2) the nominal stress intensity factor, K/sup R/. It is observed that these two measures are not equivalent during the initial stage of R-curve behavior, prior to reaching steady-state cracking. The theoretical reason for this difference is discussed. In particular, it is noted that the usual definition for the crack extension force does not correspond to the experimentally measured work of fracture in the presence of stress-induced (or pre-existing) sources of internal stress

  2. Partially coherent imaging and spatial coherence wavelets

    International Nuclear Information System (INIS)

    Castaneda, Roman

    2003-03-01

    A description of spatially partially coherent imaging based on the propagation of second order spatial coherence wavelets and marginal power spectra (Wigner distribution functions) is presented. In this dynamics, the spatial coherence wavelets will be affected by the system through its elementary transfer function. The consistency of the model with the both extreme cases of full coherent and incoherent imaging was proved. In the last case we obtained the classical concept of optical transfer function as a simple integral of the elementary transfer function. Furthermore, the elementary incoherent response function was introduced as the Fourier transform of the elementary transfer function. It describes the propagation of spatial coherence wavelets form each object point to each image point through a specific point on the pupil planes. The point spread function of the system was obtained by a simple integral of the elementary incoherent response function. (author)

  3. Coke from partially briquetted preheated coal mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Belitskii, A.N.; Sklyar, M.G.; Toryanik, Eh.I.; Bronshtein, A.P.

    1988-07-01

    Analyzes effects of partial coal charge briquetting on coking and on quality of coke for metallurgy. Effects of mixing hot coal briquets on temperature and moisture of coal were investigated on an experimental scale in a coking plant. Coal with a moisture content of 12% was used. Coking mixture consisted of 30% briquets and 70% crushed coal. Fifteen minutes after briquet mixing with coal, the mean coal charge temperature increased to 100-105 C and moisture content was lower than 2-5%. Results of laboratory investigations were verified by tests on a commercial scale. Experiments showed briquetting of weakly caking or non-caking coal charge components to be an efficient way of preventing coke quality decline. Adding 15-20% briquets consisting of weakly caking coal did not influence coke quality. Mixing hot coal briquets reduced moisture content in crushed coal, increased its temperature and reduced coking time.

  4. Inverse problems for partial differential equations

    CERN Document Server

    Isakov, Victor

    2017-01-01

    This third edition expands upon the earlier edition by adding nearly 40 pages of new material reflecting the analytical and numerical progress in inverse problems in last 10 years. As in the second edition, the emphasis is on new ideas and methods rather than technical improvements. These new ideas include use of the stationary phase method in the two-dimensional elliptic problems and of multi frequencies\\temporal data to improve stability and numerical resolution. There are also numerous corrections and improvements of the exposition throughout. This book is intended for mathematicians working with partial differential equations and their applications, physicists, geophysicists, and financial, electrical, and mechanical engineers involved with nondestructive evaluation, seismic exploration, remote sensing, and various kinds of tomography. Review of the second edition: "The first edition of this excellent book appeared in 1998 and became a standard reference for everyone interested in analysis and numerics of...

  5. Phylogenetic search through partial tree mixing

    Science.gov (United States)

    2012-01-01

    Background Recent advances in sequencing technology have created large data sets upon which phylogenetic inference can be performed. Current research is limited by the prohibitive time necessary to perform tree search on a reasonable number of individuals. This research develops new phylogenetic algorithms that can operate on tens of thousands of species in a reasonable amount of time through several innovative search techniques. Results When compared to popular phylogenetic search algorithms, better trees are found much more quickly for large data sets. These algorithms are incorporated in the PSODA application available at http://dna.cs.byu.edu/psoda Conclusions The use of Partial Tree Mixing in a partition based tree space allows the algorithm to quickly converge on near optimal tree regions. These regions can then be searched in a methodical way to determine the overall optimal phylogenetic solution. PMID:23320449

  6. Partial structures in molten AgBr

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Hiroki [Department of Condensed Matter Chemistry and Physics, Faculty of Sciences, Kyushu University, 4-2-1 Ropponmatsu, Chuo-ku, Fukuoka 810-8560 (Japan)], E-mail: ueno@gemini.rc.kyushu-u.ac.jp; Tahara, Shuta [Faculty of Pharmacy, Niigata University of Pharmacy and Applied Life Science, Higashijima, Akiha-ku, Niigata 956-8603 (Japan); Kawakita, Yukinobu [Department of Physics, Faculty of Sciences, Kyushu University, 4-2-1 Ropponmatsu, Chuo-ku, Fukuoka 810-8560 (Japan); Kohara, Shinji [Research and Utilization Division, Japan Synchrotron Radiation Research Institute (JASRI, SPring-8), 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Takeda, Shin' ichi [Department of Physics, Faculty of Sciences, Kyushu University, 4-2-1 Ropponmatsu, Chuo-ku, Fukuoka 810-8560 (Japan)

    2009-02-21

    The structure of molten AgBr has been studied by means of neutron and X-ray diffractions with the aid of structural modeling. It is confirmed that the Ag-Ag correlation has a small but well-defined first peak in the partial pair distribution function whose tail penetrates into the Ag-Br nearest neighbor distribution. This feature on the Ag-Ag correlation is intermediate between that of molten AgCl (non-superionic melt) and that of molten AgI (superionic melt). The analysis of Br-Ag-Br bond angle reveals that molten AgBr preserves a rocksalt type local ordering in the solid phase, suggesting that molten AgBr is clarified as non-superionic melt like molten AgCl.

  7. Semi-bounded partial differential operators

    CERN Document Server

    Cialdea, Alberto

    2014-01-01

    This book examines the conditions for the semi-boundedness of partial differential operators, which are interpreted in different ways. For example, today we know a great deal about L2-semibounded differential and pseudodifferential operators, although their complete characterization in analytic terms still poses difficulties, even for fairly simple operators. In contrast, until recently almost nothing was known about analytic characterizations of semi-boundedness for differential operators in other Hilbert function spaces and in Banach function spaces. This book works to address that gap. As such, various types of semi-boundedness are considered and a number of relevant conditions which are either necessary and sufficient or best possible in a certain sense are presented. The majority of the results reported on are the authors’ own contributions.

  8. Partial Differential Equations and Solitary Waves Theory

    CERN Document Server

    Wazwaz, Abdul-Majid

    2009-01-01

    "Partial Differential Equations and Solitary Waves Theory" is a self-contained book divided into two parts: Part I is a coherent survey bringing together newly developed methods for solving PDEs. While some traditional techniques are presented, this part does not require thorough understanding of abstract theories or compact concepts. Well-selected worked examples and exercises shall guide the reader through the text. Part II provides an extensive exposition of the solitary waves theory. This part handles nonlinear evolution equations by methods such as Hirota’s bilinear method or the tanh-coth method. A self-contained treatment is presented to discuss complete integrability of a wide class of nonlinear equations. This part presents in an accessible manner a systematic presentation of solitons, multi-soliton solutions, kinks, peakons, cuspons, and compactons. While the whole book can be used as a text for advanced undergraduate and graduate students in applied mathematics, physics and engineering, Part II w...

  9. Partial differential equations mathematical techniques for engineers

    CERN Document Server

    Epstein, Marcelo

    2017-01-01

    This monograph presents a graduate-level treatment of partial differential equations (PDEs) for engineers. The book begins with a review of the geometrical interpretation of systems of ODEs, the appearance of PDEs in engineering is motivated by the general form of balance laws in continuum physics. Four chapters are devoted to a detailed treatment of the single first-order PDE, including shock waves and genuinely non-linear models, with applications to traffic design and gas dynamics. The rest of the book deals with second-order equations. In the treatment of hyperbolic equations, geometric arguments are used whenever possible and the analogy with discrete vibrating systems is emphasized. The diffusion and potential equations afford the opportunity of dealing with questions of uniqueness and continuous dependence on the data, the Fourier integral, generalized functions (distributions), Duhamel's principle, Green's functions and Dirichlet and Neumann problems. The target audience primarily comprises graduate s...

  10. Partial radiative capture of resonance neutrons

    International Nuclear Information System (INIS)

    Samour, C.

    1969-01-01

    The radiative capture of resonance neutrons has been studied near the Saclay linac between 0.5 and 700 eV with time-of-flight method and a Ge(Li) detector. 195 Pt + n and 183 W + n allow the study of the distribution of partial radiative widths and their eventual correlation and also the variation of γ i > with E γ . The mean values of Ml and El transition intensities are compared in several tin isotopes. Interference effects, either between resonances or between direct capture and resonant capture are found in 195 Pt + n, 197 Au + n and 59 Co + n. The excited level schemes of a great deal of nuclei are obtained and compared with theoretical predictions. This study has been completed by an analysis of thermal spectrum. (author) [fr

  11. Reversibility of partial denaturation of DNA

    International Nuclear Information System (INIS)

    Acuna, M.I.; Mingot, F.; Davila, C.A.

    1976-01-01

    The recovery of hypochromicity in a partially denatured DNA sample when salt concentration is suddenly increased at a intermediate stage of the thermal transition is studied. The results of CsCl gradient analysis, PEG/DEX partition analysis, behaviour in a new thermal transition hydrodynamic properties and transforming ability, support the view that the process is an intramolecular double chain denaturation. The degree of denaturation irreversibility is dependent on single chain molecular weight of DNA (discontinuities denisty) and upon the helicity value at which salt concentration jump is performed. Both dependences are formally interpreted according to Elton's model for base distribution in DNA. Kinetically the process behaves as being an hydrodynamically limited rewinding. (author)

  12. Radiant exchange in partially specular architectural environments

    Science.gov (United States)

    Beamer, C. Walter; Muehleisen, Ralph T.

    2003-10-01

    The radiant exchange method, also known as radiosity, was originally developed for thermal radiative heat transfer applications. Later it was used to model architectural lighting systems, and more recently it has been extended to model acoustic systems. While there are subtle differences in these applications, the basic method is based on solving a system of energy balance equations, and it is best applied to spaces with mainly diffuse reflecting surfaces. The obvious drawback to this method is that it is based around the assumption that all surfaces in the system are diffuse reflectors. Because almost all architectural systems have at least some partially specular reflecting surfaces in the system it is important to extend the radiant exchange method to deal with this type of surface reflection. [Work supported by NSF.

  13. Tagging partially reconstructed objects with jet substructure

    Energy Technology Data Exchange (ETDEWEB)

    Freytsis, Marat, E-mail: freytsis@uoregon.edu [Department of Physics, Harvard University, Cambridge, MA, 02138 (United States); Volansky, Tomer [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel); Walsh, Jonathan R. [Ernest Orlando Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States); Berkeley Center for Theoretical Physics, University of California, Berkeley, CA 94720 (United States)

    2017-06-10

    We present a new tagger which aims at identifying partially reconstructed objects, in which only some of the constituents are collected in a single jet. As an example, we focus on top decays in which either part of the hadronically decaying W or the b jet is soft or falls outside of the top jet cone. We construct an observable to identify remnant substructure from the decay and employ aggressive jet grooming to reject QCD backgrounds. The tagger is complementary to existing ones and works well in the intermediate boost regime where jet substructure techniques usually fail. It is anticipated that a similar tagger can be used to identify non-QCD hadronic jets, such as those expected from hidden valleys.

  14. Partial body hyperthermia: a potent radioprotector

    International Nuclear Information System (INIS)

    Baydoun, S.; Alya, GH.; Taleb, M.; Mohammad, A.

    1995-12-01

    With the aim to investigate the potential role of some radioprotectors, partial body hyperthermia (PBH) was tested as a protector against the lethality induced by γ irradiation. Two groups of Wistar rats [gr.(1): Females and gr.(2): Males] were treated with PBH by 'dipping' the lower parts of the animals in water-bath at 43 C for 1 hr. Animals were, then, irradiated with a lethal dose of γ radiation (9 Gy) 20 hrs post PBH. Our results show that: -PHB has a protecting role against the lethality induced by γ irradiation with a protection factor [Survival in rats treated with PBH and radiation / survival in rats treated with radiation] of 10 in gr.(1) and 7 in gr.(2) - The role of PBH was more enhanced in females As compared with males. (author). 19 refs., 4 figs., 1 tab

  15. Partial Body Hyperthermia: A Potent radioprotector

    International Nuclear Information System (INIS)

    Baydoun, S.A.; Mohammad, A.; Alya, Gh.; Taleb, M.

    1998-01-01

    With the aim to investigate the potential role of some radioprotectors, partial body hyperthermia (PBH) was tested as a protector against the lethality induced by gamma-irradiation. Two groups of Wistar rats [ gr. (1): females and gr. (2): males] were treated with PBH by dipping the lower parts of the animals in water-bath at 43 degree for 1 hr. Animals were, then, irradiated with a lethal dose of gamma-radiation (9 Gy) 20 hr s post PBH. Our results show that: PBH has a protecting role against the lethality induced by gamma-irradiation with a protection factor [survival in rats treated with PBH and radiation/ survival in rats treated with radiation] of 10 in gr.(1) and 7 in gr. (2). The role of PBH was more enhanced in females as compared with males

  16. Serial SPECT in children with partial epilepsy

    International Nuclear Information System (INIS)

    Hosoya, Machiko; Ushiku, Hideo

    1995-01-01

    We performed serial single-photon emission CT (SPECT) with N-isopropyl-p-( 123 I)-Iodoamphetamine to measure the regional cerebral blood flow (rCBF) in 15 children with partial epilepsy. SPECT showed focal changes in 14 cases. Ten cases had abnormalities in the initial SPECT and another four cases in the second test. The cases with normal rCBF in initial SPECT had been tested in an early phase after the onset, and then decreased rCBF were observed in the second SPECT. The cases with both abnormal rCBF in the initial SPECT and improved rCBF in the second SPECT showed good prognosis in clinico-electrophysiological evolutions. In cases with abnormal changes of rCBF in the second SPECT, clinical prognosis was found to be not so good. These findings suggest that serial SPECT may be used to follow the course of epilepsy. (author)

  17. Genetic algorithm solution for partial digest problem.

    Science.gov (United States)

    Ahrabian, Hayedeh; Ganjtabesh, Mohammad; Nowzari-Dalini, Abbas; Razaghi-Moghadam-Kashani, Zahra

    2013-01-01

    One of the fundamental problems in computational biology is the construction of physical maps of chromosomes from the hybridisation experiments between unique probes and clones of chromosome fragments. Before introducing the shotgun sequencing method, Partial Digest Problem (PDP) was an intractable problem used to construct the physical maps of DNA sequence in molecular biology. In this paper, we develop a novel Genetic Algorithm (GA) for solving the PDP. This algorithm is implemented and compared with well-known existing algorithms on different types of random and real instances data, and the obtained results show the efficiency of our algorithm. Also, our GA is adapted to handle the erroneous data and their efficiency is presented for the large instances of this problem.

  18. Stereotactic radiosurgery with an upper partial denture

    International Nuclear Information System (INIS)

    Tayama, Shusaku; Kunieda, Etsuo; Takeda, Atsushi; Takeda, Toshiaki; Oku, Yohei

    2009-01-01

    A 54-year-old male with partial denture underwent stereotactic radiosurgery with an infrared camera-guided system for a metastatic brain tumor arising from lung cancer. Although this method utilizes a biteplate mounted on the upper jaw to detect head movement, the patient only had four teeth in his upper jaw. In order to stabilize the biteplate, the maxillary denture was fixed to the biteplate with an autopolymerizing resin. In addition, the rest-occlusal position of the lower jaw was impressed on the inferior surface of the biteplate with an autopolymerizing resin. To assess reproducibility and stability, the distance between the left and right incus and left and right markers was measured during pre-planning, as well as before and after stereotactic irradiation. Wearing the biteplate ensures the accuracy of radiotherapy planning for the implementation of radiosurgery in patients who have many maxillary teeth missing. However, a large degree of error was observed when the biteplate was removed. (author)

  19. Faithful teleportation with partially entangled states

    International Nuclear Information System (INIS)

    Gour, Gilad

    2004-01-01

    We write explicitly a general protocol for faithful teleportation of a d-state particle (qudit) via a partially entangled pair of (pure) n-state particles. The classical communication cost (CCC) of the protocol is log 2 (nd) bits, and it is implemented by a projective measurement performed by Alice, and a unitary operator performed by Bob (after receiving from Alice the measurement result). We prove the optimality of our protocol by a comparison with the concentrate and teleport strategy. We also show that if d>n/2, or if there is no residual entanglement left after the faithful teleportation, the CCC of any protocol is at least log 2 (nd) bits. Furthermore, we find a lower bound on the CCC in the process transforming one bipartite state to another by means of local operation and classical communication

  20. Tagging partially reconstructed objects with jet substructure

    International Nuclear Information System (INIS)

    Freytsis, Marat; Volansky, Tomer; Walsh, Jonathan R.

    2017-01-01

    We present a new tagger which aims at identifying partially reconstructed objects, in which only some of the constituents are collected in a single jet. As an example, we focus on top decays in which either part of the hadronically decaying W or the b jet is soft or falls outside of the top jet cone. We construct an observable to identify remnant substructure from the decay and employ aggressive jet grooming to reject QCD backgrounds. The tagger is complementary to existing ones and works well in the intermediate boost regime where jet substructure techniques usually fail. It is anticipated that a similar tagger can be used to identify non-QCD hadronic jets, such as those expected from hidden valleys.

  1. Tagging partially reconstructed objects with jet substructure

    Science.gov (United States)

    Freytsis, Marat; Volansky, Tomer; Walsh, Jonathan R.

    2017-06-01

    We present a new tagger which aims at identifying partially reconstructed objects, in which only some of the constituents are collected in a single jet. As an example, we focus on top decays in which either part of the hadronically decaying W or the b jet is soft or falls outside of the top jet cone. We construct an observable to identify remnant substructure from the decay and employ aggressive jet grooming to reject QCD backgrounds. The tagger is complementary to existing ones and works well in the intermediate boost regime where jet substructure techniques usually fail. It is anticipated that a similar tagger can be used to identify non-QCD hadronic jets, such as those expected from hidden valleys.

  2. Prediction uncertainty in seasonal partial duration series

    DEFF Research Database (Denmark)

    Rasmussen, Peter Funder; Rosbjerg, Dan

    1991-01-01

    In order to obtain a good description of the exceedances in a partial duration series it is often necessary to divide the year into a number (2-4) of seasons. Hereby a stationary exceedance distribution can be maintained within each season. This type of seasonal models may, however, not be suitable...... for prediction purposes due to the large number of parameters required. In the particular case with exponentially distributed exceedances and Poissonian occurrence times the precision of the T year event estimator has been thoroughly examined considering both seasonal and nonseasonal models. The two......-seasonal probability density function of the T year event estimator has been deduced and used in the assessment of the precision of approximate moments. The nonseasonal approach covered both a total omission of seasonality by pooling data from different flood seasons and a discarding of nonsignificant season(s) before...

  3. Partial hypopituitarism and Langerhans cell histiocytosis

    Science.gov (United States)

    Balaguruswamy, S; Chattington, P D

    2011-01-01

    A case of multisystem Langerhans cell histiocytosis with pituitary involvement nearly 20 years after initial presentation. A 48-year-old man had histiocytosis X 22 years ago initially involving the groin; subsequently his external auditory meatus, scalp, gum, mandibular bone, perineum and axilla were involved and treated. The pituitary gland was involved 4 years ago. A thyrotropin-releasing hormone test showed delayed response suggestive of hypothalamic disease. Prolactin levels were normal. A gonadotropin-releasing hormone test showed impaired testosterone and gonadotrophin response in keeping with pituitary disease. A glucagon stimulation test showed an impaired growth hormone response but a normal cortisol increase. MRI pituitary showed an empty sella. There was no evidence of diabetes insipidus. Bone mineral densitometry was normal. He has partial hypopituitarism needing thyroxine and testosterone replacement. He also developed type 2 diabetes mellitus 9 years ago. He is closely monitored for any development of diabetes insipidus and the need for growth hormone supplementation. PMID:22715201

  4. Oculomotor impairment during chronic partial sleep deprivation.

    Science.gov (United States)

    Russo, M; Thomas, M; Thorne, D; Sing, H; Redmond, D; Rowland, L; Johnson, D; Hall, S; Krichmar, J; Balkin, T

    2003-04-01

    The effects of chronic partial sleep (sleep deprivation) and extended sleep (sleep augmentation) followed by recovery sleep on oculomotor function were evaluated in normal subjects to explore the usefulness of oculomotor assessment for alertness monitoring in fitness-for-duty testing. Sixty-six commercial drivers (24-62 years, 50m/16f) participated in a 15 day study composed of 3 training days with 8h time in bed per night, 7 experimental days with subjects randomly assigned to either 3, 5, 7, or 9h time in bed, and 3 recovery nights with 8h time in bed. Data from 57 subjects were used. Saccadic velocity (SV), initial pupil diameter (IPD), latency to pupil constriction (CL), and amplitude of pupil constriction (CA) were assessed and correlated with the sleep latency test (SLT), the Stanford sleepiness scale (SSS), and simulated driving performance. Regression analyses showed that SV slowed significantly in the 3 and 5h groups, IPD decreased significantly in the 9h group, and CL increased significantly in the 3h group. SLT and SSS significantly correlated with SV, IPD, CL, and driving accidents for the 3h group, and with CL for the 5h group. Analyses also showed a significant negative correlation between decreasing SV and increasing driving accidents in the 3h group and a significant negative correlation between IPD and driving accidents for the 7h group. The results demonstrate a sensitivity primarily of SV to sleepiness, and a correlation of SV and IPD to impaired simulated driving performance, providing evidence for the potential utility of oculomotor indicators in the detection of excessive sleepiness and deterioration of complex motor performance with chronic partial sleep restriction. This paper shows a relationship between sleep deprivation and oculomotor measures, and suggests a potential utility for oculometrics in assessing operational performance readiness under sleep restricted conditions.

  5. Multiple symbol partially coherent detection of MPSK

    Science.gov (United States)

    Simon, M. K.; Divsalar, D.

    1992-01-01

    It is shown that by using the known (or estimated) value of carrier tracking loop signal to noise ratio (SNR) in the decision metric, it is possible to improve the error probability performance of a partially coherent multiple phase-shift-keying (MPSK) system relative to that corresponding to the commonly used ideal coherent decision rule. Using a maximum-likeihood approach, an optimum decision metric is derived and shown to take the form of a weighted sum of the ideal coherent decision metric (i.e., correlation) and the noncoherent decision metric which is optimum for differential detection of MPSK. The performance of a receiver based on this optimum decision rule is derived and shown to provide continued improvement with increasing length of observation interval (data symbol sequence length). Unfortunately, increasing the observation length does not eliminate the error floor associated with the finite loop SNR. Nevertheless, in the limit of infinite observation length, the average error probability performance approaches the algebraic sum of the error floor and the performance of ideal coherent detection, i.e., at any error probability above the error floor, there is no degradation due to the partial coherence. It is shown that this limiting behavior is virtually achievable with practical size observation lengths. Furthermore, the performance is quite insensitive to mismatch between the estimate of loop SNR (e.g., obtained from measurement) fed to the decision metric and its true value. These results may be of use in low-cost Earth-orbiting or deep-space missions employing coded modulations.

  6. Multidisciplinary approach to restoring anterior maxillary partial edentulous area using an IPS Empress 2 fixed partial denture: a clinical report.

    Science.gov (United States)

    Dundar, Mine; Gungor, M Ali; Cal, Ebru

    2003-04-01

    Esthetics is a major concern during restoration of anterior partial edentulous areas. All-ceramic fixed partial dentures may provide better esthetics and biocompatibility in the restoration of anterior teeth. This clinic report describes a multidisciplinary approach and treatment procedures with an IPS Empress 2 fixed partial denture to restore missing anterior teeth.

  7. Telescopic Partial Dentures-Concealed Technology.

    Science.gov (United States)

    Bhagat, Tushar Vitthalrao; Walke, Ashwini Nareshchandra

    2015-09-01

    The ideal goal of good dentist is to restore the missing part of oral structure, phonetics, his look and the most important is restored the normal health of the patient, which is hampered due to less or insufficient intake of food. Removable partial denture (RPD) treatment option is considered as a notion, which precludes the inevitability of "floating plastic" in edentulous mouth, that many times fail to fulfill the above essential of the patients. In modern dentistry, though the dental implants or fixed partial denture is the better options, but they have certain limitations. However, overdentures and particularly telescopic denture is the overlooked technology in dentistry that would be a boon for such needy patients. Telescopic denture is especially indicated in the distal edentulous area with minimum two teeth bilaterally present with a good amount of periodontal support. This treatment modality is sort of preventive prosthodontics remedy, which in a conservative manner preserve the remaining teeth and helps in conservation of alveolar bone ultimately. There are two tenets related to this option, one is constant conservation edentulous ridge around the retained tooth and the most important is the endless existence of periodontal sensory action that directs and monitor gnathodynamic task. In this option the primary coping or inner coping are cemented on the prepared tooth, and a similar removable outer or inner telescopic crown placed tightly by using a mechanism of tenso-friction, this is firmly attached to a removable RPD in place without moving or rocking of the prosthesis, which is the common compliant of almost all patients of RPD. Copings are also protecting the abutment from tooth decay and also offers stabilization and maintaining of the outer crown. The outer crown engages the inner coping and gives as an anchor for the remainder of the dentition. This work is the review of telescopic prosthesis which is well supported by the case discussion, and

  8. Compatible Spatial Discretizations for Partial Differential Equations

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, Douglas, N, ed.

    2004-11-25

    From May 11--15, 2004, the Institute for Mathematics and its Applications held a hot topics workshop on Compatible Spatial Discretizations for Partial Differential Equations. The numerical solution of partial differential equations (PDE) is a fundamental task in science and engineering. The goal of the workshop was to bring together a spectrum of scientists at the forefront of the research in the numerical solution of PDEs to discuss compatible spatial discretizations. We define compatible spatial discretizations as those that inherit or mimic fundamental properties of the PDE such as topology, conservation, symmetries, and positivity structures and maximum principles. A wide variety of discretization methods applied across a wide range of scientific and engineering applications have been designed to or found to inherit or mimic intrinsic spatial structure and reproduce fundamental properties of the solution of the continuous PDE model at the finite dimensional level. A profusion of such methods and concepts relevant to understanding them have been developed and explored: mixed finite element methods, mimetic finite differences, support operator methods, control volume methods, discrete differential forms, Whitney forms, conservative differencing, discrete Hodge operators, discrete Helmholtz decomposition, finite integration techniques, staggered grid and dual grid methods, etc. This workshop seeks to foster communication among the diverse groups of researchers designing, applying, and studying such methods as well as researchers involved in practical solution of large scale problems that may benefit from advancements in such discretizations; to help elucidate the relations between the different methods and concepts; and to generally advance our understanding in the area of compatible spatial discretization methods for PDE. Particular points of emphasis included: + Identification of intrinsic properties of PDE models that are critical for the fidelity of numerical

  9. Two cases of partial trisomy 4p and partial trisomy 14q.

    Science.gov (United States)

    Kim, Yeo-Hyang; Kim, Heung-Sik; Ryoo, Nam-Hee; Ha, Jung-Sook

    2013-01-01

    We present clinical and cytogenetic data on 2 cases of partial trisomy 4p and partial trisomy 14q. Both patients had an extra der(14)t(4;14)(p15.31;q12) chromosome due to a 3:1 segregation from a balanced translocation carrier mother. Array analyses indicated that their chromosomal breakpoints were similar, but there was no relationship between the 2 families. Both patients showed prominent growth retardation and psychomotor developmental delay. Other phenotypic manifestations were generally mild and variable; for example, patient 1 had a short palpebral fissure and low-set ears whereas patient 2 had a round face, asymmetric eyes, small ears, a short neck, finger/toe abnormalities, and behavioral problems.

  10. Caudal Regression Syndrome with Partial Agenesis of the Corpus callosum and Partial Lobar Holoprosencephaly

    Science.gov (United States)

    Hashami, Hilal Al; Bataclan, Maria F; Mathew, Mariam; Krishnan, Lalitha

    2010-01-01

    Caudal regression syndrome is a rare fetal condition of diabetic pregnancy. Although the exact mechanism is not known, hyperglycaemia during embryogenesis seems to act as a teratogen. Independently, caudal regression syndrome (CRS), agenesis of the corpus callosum (ACC) and partial lobar holoprosencephaly (HPE) have been reported in infants of diabetic mothers. To our knowledge, a combination of all these three conditions has not been reported so far. PMID:21509087

  11. Caudal Regression Syndrome with Partial Agenesis of the Corpus callosum and Partial Lobar Holoprosencephaly: Case report.

    Science.gov (United States)

    Hashami, Hilal Al; Bataclan, Maria F; Mathew, Mariam; Krishnan, Lalitha

    2010-04-01

    Caudal regression syndrome is a rare fetal condition of diabetic pregnancy. Although the exact mechanism is not known, hyperglycaemia during embryogenesis seems to act as a teratogen. Independently, caudal regression syndrome (CRS), agenesis of the corpus callosum (ACC) and partial lobar holoprosencephaly (HPE) have been reported in infants of diabetic mothers. To our knowledge, a combination of all these three conditions has not been reported so far.

  12. New approach to breast cancer CAD using partial least squares and kernel-partial least squares

    Science.gov (United States)

    Land, Walker H., Jr.; Heine, John; Embrechts, Mark; Smith, Tom; Choma, Robert; Wong, Lut

    2005-04-01

    Breast cancer is second only to lung cancer as a tumor-related cause of death in women. Currently, the method of choice for the early detection of breast cancer is mammography. While sensitive to the detection of breast cancer, its positive predictive value (PPV) is low, resulting in biopsies that are only 15-34% likely to reveal malignancy. This paper explores the use of two novel approaches called Partial Least Squares (PLS) and Kernel-PLS (K-PLS) to the diagnosis of breast cancer. The approach is based on optimization for the partial least squares (PLS) algorithm for linear regression and the K-PLS algorithm for non-linear regression. Preliminary results show that both the PLS and K-PLS paradigms achieved comparable results with three separate support vector learning machines (SVLMs), where these SVLMs were known to have been trained to a global minimum. That is, the average performance of the three separate SVLMs were Az = 0.9167927, with an average partial Az (Az90) = 0.5684283. These results compare favorably with the K-PLS paradigm, which obtained an Az = 0.907 and partial Az = 0.6123. The PLS paradigm provided comparable results. Secondly, both the K-PLS and PLS paradigms out performed the ANN in that the Az index improved by about 14% (Az ~ 0.907 compared to the ANN Az of ~ 0.8). The "Press R squared" value for the PLS and K-PLS machine learning algorithms were 0.89 and 0.9, respectively, which is in good agreement with the other MOP values.

  13. Hydraulic behaviour of a partially uncovered core

    International Nuclear Information System (INIS)

    Fischer, K.; Hafner, W.

    1989-10-01

    A critical review of experimental data and theoretical models relevant to the thermohydraulic processes in a partially uncovered core has been performed. Presently available optimized thermohydraulic codes should be able to predict swell level elevations within an error band of ± 0.5 m. Rod temperature rising velocities could be predicted within an error bandwidth of ± 10%, provided the correct rod heat capacity is given. A general statement about the accuracy of predicted rod temperatures is not possible because the errors increase with simulation time. Highest errors are expected for long transients with low heating rates and low steam velocities. As a result, three areas for additional research are suggested: - a high-pressure test at 120 bar to complete the void correlation data base, - a low steam flow - low power experiment to improve heat transfer correlations, - a numerical investigation of three-dimensional effects in the reactor core with unequally heated rod bundles. For the present state of 1-dimensional experiments and models, suggestions for a satisfactory modeling have been derived. The suggested further work could improve the modelling capabilities and the code reliability for some limiting cases like high pressure boil-off, low-power long-term steam cooling, and unequal heating of neighbouring bundles considerably

  14. Laparoscopic Partial Hepatectomy of Focal Nodular Hyperplasia

    Directory of Open Access Journals (Sweden)

    Mayu Sakata

    2012-11-01

    Full Text Available Focal nodular hyperplasia is a benign liver lesion incidentally discovered with increasing frequency because of the proliferation of imaging studies. Radiographic characterization can diagnose this pathologic lesion and nonoperative therapy is the standard of care. However, surgical resection may be required for diagnostic reasons or symptomatic patients. Depending on the anatomic location of the lesion, biopsy and/or resection can be performed laparoscopically. We herein report the case of a 26-year-old Japanese woman with a hepatic tumor who required a medical examination. Her medical history was negative for alcohol abuse, oral contraceptive administration and trauma. Clinical examination showed no significant symptoms. Ultrasonography, computed tomography and magnetic resonance imaging showed a mass located in the left lateral segment of the liver with a diameter of about 40 mm. It was difficult to diagnose the tumor definitively from these imaging studies, so we performed laparoscopic partial hepatectomy with successive firing of endoscopic staplers. The histopathological diagnosis was focal nodular hyperplasia. Surgical procedures and postoperative course were uneventful and the patient was discharged from the hospital on postoperative day 5.

  15. Parameter Estimation of Partial Differential Equation Models.

    Science.gov (United States)

    Xun, Xiaolei; Cao, Jiguo; Mallick, Bani; Carroll, Raymond J; Maity, Arnab

    2013-01-01

    Partial differential equation (PDE) models are commonly used to model complex dynamic systems in applied sciences such as biology and finance. The forms of these PDE models are usually proposed by experts based on their prior knowledge and understanding of the dynamic system. Parameters in PDE models often have interesting scientific interpretations, but their values are often unknown, and need to be estimated from the measurements of the dynamic system in the present of measurement errors. Most PDEs used in practice have no analytic solutions, and can only be solved with numerical methods. Currently, methods for estimating PDE parameters require repeatedly solving PDEs numerically under thousands of candidate parameter values, and thus the computational load is high. In this article, we propose two methods to estimate parameters in PDE models: a parameter cascading method and a Bayesian approach. In both methods, the underlying dynamic process modeled with the PDE model is represented via basis function expansion. For the parameter cascading method, we develop two nested levels of optimization to estimate the PDE parameters. For the Bayesian method, we develop a joint model for data and the PDE, and develop a novel hierarchical model allowing us to employ Markov chain Monte Carlo (MCMC) techniques to make posterior inference. Simulation studies show that the Bayesian method and parameter cascading method are comparable, and both outperform other available methods in terms of estimation accuracy. The two methods are demonstrated by estimating parameters in a PDE model from LIDAR data.

  16. Correlations in a partially degenerate electron plasma

    Energy Technology Data Exchange (ETDEWEB)

    Chihara, Junzo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    The density-functional theory proves that an ion-electron mixture can be treated as a one-component liquid interacting only via a pairwise interaction in the evaluation of the ion-ion radial distribution function (RDF), and provides a set of integral equations: one is an integral equation for the ion-ion RDF and another for an effective ion-ion interaction, which depends on the ion-ion RDF. This formulation gives a set of integral equation to calculate plasma structures with combined use of the electron-electron correlations in a partially degenerate electron plasma. Therefore, it is important for this purpose to determine the electron-electron correlations at a arbitrary temperature. Here, they are calculated by the quantal version of the hypernetted chain (HNC) equation. On the basis of the jellium-vacancy model, the ionic and electronic structures of rubidium are calculated for the range from liquid metal to plasma states by increasing the temperature at the fixed density using the electron-correlation results. (author)

  17. Partial observation control in an anticipating environment

    International Nuclear Information System (INIS)

    Oeksendal, B; Sulem, A

    2004-01-01

    A study is made of a controlled stochastic system whose state X(t) at time t is described by a stochastic differential equation driven by Levy processes with filtration {F t } telementof[0,T] . The system is assumed to be anticipating, in the sense that the coefficients are assumed to be adapted to a filtration {G t } t≥0 with F t subset of equal G t for all t element of [0,T]. The corresponding anticipating stochastic differential equation is interpreted in the sense of forward integrals, which naturally generalize semimartingale integrals. The admissible controls are assumed to be adapted to a filtration {E t } telementof[0,T] such that E t subset of equal F t for all t element of [0,T]. The general problem is to maximize a given performance functional of this system over all admissible controls. This is a partial observation stochastic control problem in an anticipating environment. Examples of applications include stochastic volatity models in finance, insider influenced financial markets, and stochastic control of systems with delayed noise effects. Some particular cases in finance, involving optimal portfolios with logarithmic utility, are solved explicitly

  18. Precise Point Positioning with Partial Ambiguity Fixing.

    Science.gov (United States)

    Li, Pan; Zhang, Xiaohong

    2015-06-10

    Reliable and rapid ambiguity resolution (AR) is the key to fast precise point positioning (PPP). We propose a modified partial ambiguity resolution (PAR) method, in which an elevation and standard deviation criterion are first used to remove the low-precision ambiguity estimates for AR. Subsequently the success rate and ratio-test are simultaneously used in an iterative process to increase the possibility of finding a subset of decorrelated ambiguities which can be fixed with high confidence. One can apply the proposed PAR method to try to achieve an ambiguity-fixed solution when full ambiguity resolution (FAR) fails. We validate this method using data from 450 stations during DOY 021 to 027, 2012. Results demonstrate the proposed PAR method can significantly shorten the time to first fix (TTFF) and increase the fixing rate. Compared with FAR, the average TTFF for PAR is reduced by 14.9% for static PPP and 15.1% for kinematic PPP. Besides, using the PAR method, the average fixing rate can be increased from 83.5% to 98.2% for static PPP, from 80.1% to 95.2% for kinematic PPP respectively. Kinematic PPP accuracy with PAR can also be significantly improved, compared to that with FAR, due to a higher fixing rate.

  19. Partial Differential Equations in General Relativity

    International Nuclear Information System (INIS)

    Choquet-Bruhat, Yvonne

    2008-01-01

    General relativity is a physical theory basic in the modeling of the universe at the large and small scales. Its mathematical formulation, the Einstein partial differential equations, are geometrically simple, but intricate for the analyst, involving both hyperbolic and elliptic PDE, with local and global problems. Many problems remain open though remarkable progress has been made recently towards their solutions. Alan Rendall's book states, in a down-to-earth form, fundamental results used to solve different types of equations. In each case he gives applications to special models as well as to general properties of Einsteinian spacetimes. A chapter on ODE contains, in particular, a detailed discussion of Bianchi spacetimes. A chapter entitled 'Elliptic systems' treats the Einstein constraints. A chapter entitled 'Hyperbolic systems' is followed by a chapter on the Cauchy problem and a chapter 'Global results' which contains recently proved theorems. A chapter is dedicated to the Einstein-Vlasov system, of which the author is a specialist. On the whole, the book surveys, in a concise though precise way, many essential results of recent interest in mathematical general relativity, and it is very clearly written. Each chapter is followed by an up to date bibliography. In conclusion, this book will be a valuable asset to relativists who wish to learn clearly-stated mathematical results and to mathematicians who want to penetrate into the subtleties of general relativity, as a mathematical and physical theory. (book review)

  20. Generalized geometry and partial supersymmetry breaking

    Energy Technology Data Exchange (ETDEWEB)

    Triendl, Hagen Mathias

    2010-08-15

    This thesis consists of two parts. In the first part we use the formalism of (exceptional) generalized geometry to derive the scalar field space of SU(2) x SU(2)-structure compactifications. We show that in contrast to SU(3) x SU(3) structures, there is no dynamical SU(2) x SU(2) structure interpolating between an SU(2) structure and an identity structure. Furthermore, we derive the scalar manifold of the low-energy effective action for consistent Kaluza-Klein truncations as expected from N = 4 supergravity. In the second part we then determine the general conditions for the existence of stable Minkowski and AdS N = 1 vacua in spontaneously broken gauged N = 2 supergravities and construct the general solution under the assumption that two appropriate commuting isometries exist in the hypermultiplet sector. Furthermore, we derive the low-energy effective action below the scale of partial supersymmetry breaking and show that it satisfies the constraints of N = 1 supergravity. We then apply the discussion to special quaternionic-Kaehler geometries which appear in the low-energy limit of SU(3) x SU(3)-structure compactifications and construct Killing vectors with the right properties. Finally we discuss the string theory realizations for these solutions. (orig.)

  1. Hydrogen adsorption on partially oxidised microporous carbons

    International Nuclear Information System (INIS)

    J B Parra; C O Ania; C J Duran Valle; M L Sanchez; C Otero Arean

    2005-01-01

    The search for cost effective adsorbents for large scale gas separation, storage and transport constitutes a present day strategic issue in the energy sector, propelled mainly by the potential use of hydrogen as an energy vector in a sustainable (and cleaner) energy scenario. Both, activated carbons and carbon based nano-structured materials have been proposed as potential candidates for reversible hydrogen storage in cryogenically cooled vessels. For that purpose, surface modification so as to enhance the gas solid interaction energy is desirable. We report on hydrogen adsorption on microporous (active) carbons which have been partially oxidised with nitric acid and ammonium persulfate. From the corresponding hydrogen adsorption isotherms (Fig. 1) an isosteric heat of about 3 kJ mol -1 was derived. This value is in agreement with that of about 3 to 4 kJ mol -1 obtained by quantum chemical calculations on the interaction between the hydrogen molecule and simple model systems (Fig. 2) of both, hydroxyl and carboxyl groups. Further research is in progress with a view to further increases the gas solid interaction energy. However, the values so far obtained are significantly larger than the liquefaction enthalpy of hydrogen: 0.90 kJ mol -1 ; and this is relevant to both, hydrogen separation from gas mixtures and cryogenic hydrogen storage. (authors)

  2. Partial dehydration and cryopreservation of Citrus seeds.

    Science.gov (United States)

    Graiver, Natalia; Califano, Alicia; Zaritzky, Noemí

    2011-11-01

    Three categories of seed storage behavior are generally recognized among plant species: orthodox, intermediate and recalcitrant. Intermediate seeds cannot be stored in liquid nitrogen (LN) without a previous partial dehydration process. The water content (WC) of the seeds at the moment of immersion in LN must be regarded as the most critical factor in cryopreservation. The purpose of this study was to investigate the basis of the optimal hydration status for cryopreservation of Citrus seeds: C. sinensis (sweet orange), C. paradisi (grapefruit), C. reticulata (mandarin) in LN. To study the tolerance to dehydration and LN exposure, seeds were desiccated by equilibration at relative humidities between 11 and 95%. Sorption isotherms were determined and modeled; lipid content of the seeds was measured. Seed desiccation sensitivity was quantified by the quantal response model. Differential scanning calorimetry (DSC) thermograms were determined on cotyledon tissue at different moisture contents to measure ice melting enthalpies and unfrozen WC. Samples of total seed lipid extract were also analyzed by DSC to identify lipid transitions in the thermograms. The limit of hydration for LN Citrus seeds treatment corresponded to the unfrozen WC in the tissue, confirming that seed survival strictly depended on avoidance of intracellular ice formation. Copyright © 2011 Society of Chemical Industry.

  3. Adaptive partial volume classification of MRI data

    International Nuclear Information System (INIS)

    Chiverton, John P; Wells, Kevin

    2008-01-01

    Tomographic biomedical images are commonly affected by an imaging artefact known as the partial volume (PV) effect. The PV effect produces voxels composed of a mixture of tissues in anatomical magnetic resonance imaging (MRI) data resulting in a continuity of these tissue classes. Anatomical MRI data typically consist of a number of contiguous regions of tissues or even contiguous regions of PV voxels. Furthermore discontinuities exist between the boundaries of these contiguous image regions. The work presented here probabilistically models the PV effect using spatial regularization in the form of continuous Markov random fields (MRFs) to classify anatomical MRI brain data, simulated and real. A unique approach is used to adaptively control the amount of spatial regularization imposed by the MRF. Spatially derived image gradient magnitude is used to identify the discontinuities between image regions of contiguous tissue voxels and PV voxels, imposing variable amounts of regularization determined by simulation. Markov chain Monte Carlo (MCMC) is used to simulate the posterior distribution of the probabilistic image model. Promising quantitative results are presented for PV classification of simulated and real MRI data of the human brain.

  4. Partial Differential Equations in General Relativity

    Energy Technology Data Exchange (ETDEWEB)

    Choquet-Bruhat, Yvonne

    2008-09-07

    General relativity is a physical theory basic in the modeling of the universe at the large and small scales. Its mathematical formulation, the Einstein partial differential equations, are geometrically simple, but intricate for the analyst, involving both hyperbolic and elliptic PDE, with local and global problems. Many problems remain open though remarkable progress has been made recently towards their solutions. Alan Rendall's book states, in a down-to-earth form, fundamental results used to solve different types of equations. In each case he gives applications to special models as well as to general properties of Einsteinian spacetimes. A chapter on ODE contains, in particular, a detailed discussion of Bianchi spacetimes. A chapter entitled 'Elliptic systems' treats the Einstein constraints. A chapter entitled 'Hyperbolic systems' is followed by a chapter on the Cauchy problem and a chapter 'Global results' which contains recently proved theorems. A chapter is dedicated to the Einstein-Vlasov system, of which the author is a specialist. On the whole, the book surveys, in a concise though precise way, many essential results of recent interest in mathematical general relativity, and it is very clearly written. Each chapter is followed by an up to date bibliography. In conclusion, this book will be a valuable asset to relativists who wish to learn clearly-stated mathematical results and to mathematicians who want to penetrate into the subtleties of general relativity, as a mathematical and physical theory. (book review)

  5. Catalytic partial oxidation of pyrolysis oils

    Science.gov (United States)

    Rennard, David Carl

    2009-12-01

    This thesis explores the catalytic partial oxidation (CPO) of pyrolysis oils to syngas and chemicals. First, an exploration of model compounds and their chemistries under CPO conditions is considered. Then CPO experiments of raw pyrolysis oils are detailed. Finally, plans for future development in this field are discussed. In Chapter 2, organic acids such as propionic acid and lactic acid are oxidized to syngas over Pt catalysts. Equilibrium production of syngas can be achieved over Rh-Ce catalysts; alternatively mechanistic evidence is derived using Pt catalysts in a fuel rich mixture. These experiments show that organic acids, present in pyrolysis oils up to 25%, can undergo CPO to syngas or for the production of chemicals. As the fossil fuels industry also provides organic chemicals such as monomers for plastics, the possibility of deriving such species from pyrolysis oils allows for a greater application of the CPO of biomass. However, chemical production is highly dependent on the originating molecular species. As bio oil comprises up to 400 chemicals, it is essential to understand how difficult it would be to develop a pure product stream. Chapter 3 continues the experimentation from Chapter 2, exploring the CPO of another organic functionality: the ester group. These experiments demonstrate that equilibrium syngas production is possible for esters as well as acids in autothermal operation with contact times as low as tau = 10 ms over Rh-based catalysts. Conversion for these experiments and those with organic acids is >98%, demonstrating the high reactivity of oxygenated compounds on noble metal catalysts. Under CPO conditions, esters decompose in a predictable manner: over Pt and with high fuel to oxygen, non-equilibrium products show a similarity to those from related acids. A mechanism is proposed in which ethyl esters thermally decompose to ethylene and an acid, which decarbonylates homogeneously, driven by heat produced at the catalyst surface. Chapter 4

  6. Background Selection in Partially Selfing Populations

    Science.gov (United States)

    Roze, Denis

    2016-01-01

    Self-fertilizing species often present lower levels of neutral polymorphism than their outcrossing relatives. Indeed, selfing automatically increases the rate of coalescence per generation, but also enhances the effects of background selection and genetic hitchhiking by reducing the efficiency of recombination. Approximations for the effect of background selection in partially selfing populations have been derived previously, assuming tight linkage between deleterious alleles and neutral loci. However, loosely linked deleterious mutations may have important effects on neutral diversity in highly selfing populations. In this article, I use a general method based on multilocus population genetics theory to express the effect of a deleterious allele on diversity at a linked neutral locus in terms of moments of genetic associations between loci. Expressions for these genetic moments at equilibrium are then computed for arbitrary rates of selfing and recombination. An extrapolation of the results to the case where deleterious alleles segregate at multiple loci is checked using individual-based simulations. At high selfing rates, the tight linkage approximation underestimates the effect of background selection in genomes with moderate to high map length; however, another simple approximation can be obtained for this situation and provides accurate predictions as long as the deleterious mutation rate is not too high. PMID:27075726

  7. MICROWAVE INTERACTIONS WITH INHOMOGENEOUS PARTIALLY IONIZED PLASMA

    Energy Technology Data Exchange (ETDEWEB)

    Kritz, A. H.

    1962-11-15

    Microwave interactions with inhomogeneous plasmas are often studied by employing a simplified electromagnetic approach, i.e., by representing the effects of the plasma by an effective dielectric coefficient. The problems and approximations associated with this procedure are discussed. The equation describing the microwave field in an inhomogeneous partially ionized plasma is derived, and the method that is applied to obtain the reflected, transmitted, and absorbed intensities in inhomogeneous plasmas is presented. The interactions of microwaves with plasmas having Gaussian electron density profiles are considered. The variation of collision frequency with position is usually neglected. In general, the assumption of constant collision frequency is not justified; e.g., for a highly ionized plasma, the electron density profile determines, in part, the profile of the electron-ion collision frequency. The effect of the variation of the collision frequency profile on the interaction of microwaves with inhomogeneous plasmas is studied in order to obtain an estimate of the degree of error that may result when constant collision frequency is assumed instead of a more realistic collision frequency profile. It is shown that the degree of error is of particular importance when microwave analysis is used as a plasma diagnostic. (auth)

  8. Generalized geometry and partial supersymmetry breaking

    International Nuclear Information System (INIS)

    Triendl, Hagen Mathias

    2010-08-01

    This thesis consists of two parts. In the first part we use the formalism of (exceptional) generalized geometry to derive the scalar field space of SU(2) x SU(2)-structure compactifications. We show that in contrast to SU(3) x SU(3) structures, there is no dynamical SU(2) x SU(2) structure interpolating between an SU(2) structure and an identity structure. Furthermore, we derive the scalar manifold of the low-energy effective action for consistent Kaluza-Klein truncations as expected from N = 4 supergravity. In the second part we then determine the general conditions for the existence of stable Minkowski and AdS N = 1 vacua in spontaneously broken gauged N = 2 supergravities and construct the general solution under the assumption that two appropriate commuting isometries exist in the hypermultiplet sector. Furthermore, we derive the low-energy effective action below the scale of partial supersymmetry breaking and show that it satisfies the constraints of N = 1 supergravity. We then apply the discussion to special quaternionic-Kaehler geometries which appear in the low-energy limit of SU(3) x SU(3)-structure compactifications and construct Killing vectors with the right properties. Finally we discuss the string theory realizations for these solutions. (orig.)

  9. Partial differential equations methods, applications and theories

    CERN Document Server

    Hattori, Harumi

    2013-01-01

    This volume is an introductory level textbook for partial differential equations (PDE's) and suitable for a one-semester undergraduate level or two-semester graduate level course in PDE's or applied mathematics. Chapters One to Five are organized according to the equations and the basic PDE's are introduced in an easy to understand manner. They include the first-order equations and the three fundamental second-order equations, i.e. the heat, wave and Laplace equations. Through these equations we learn the types of problems, how we pose the problems, and the methods of solutions such as the separation of variables and the method of characteristics. The modeling aspects are explained as well. The methods introduced in earlier chapters are developed further in Chapters Six to Twelve. They include the Fourier series, the Fourier and the Laplace transforms, and the Green's functions. The equations in higher dimensions are also discussed in detail. This volume is application-oriented and rich in examples. Going thr...

  10. Epidemics in partially overlapped multiplex networks.

    Directory of Open Access Journals (Sweden)

    Camila Buono

    Full Text Available Many real networks exhibit a layered structure in which links in each layer reflect the function of nodes on different environments. These multiple types of links are usually represented by a multiplex network in which each layer has a different topology. In real-world networks, however, not all nodes are present on every layer. To generate a more realistic scenario, we use a generalized multiplex network and assume that only a fraction [Formula: see text] of the nodes are shared by the layers. We develop a theoretical framework for a branching process to describe the spread of an epidemic on these partially overlapped multiplex networks. This allows us to obtain the fraction of infected individuals as a function of the effective probability that the disease will be transmitted [Formula: see text]. We also theoretically determine the dependence of the epidemic threshold on the fraction [Formula: see text] of shared nodes in a system composed of two layers. We find that in the limit of [Formula: see text] the threshold is dominated by the layer with the smaller isolated threshold. Although a system of two completely isolated networks is nearly indistinguishable from a system of two networks that share just a few nodes, we find that the presence of these few shared nodes causes the epidemic threshold of the isolated network with the lower propagating capacity to change discontinuously and to acquire the threshold of the other network.

  11. Working memory is partially preserved during sleep.

    Directory of Open Access Journals (Sweden)

    Jérôme Daltrozzo

    Full Text Available Although several cognitive processes, including speech processing, have been studied during sleep, working memory (WM has never been explored up to now. Our study assessed the capacity of WM by testing speech perception when the level of background noise and the sentential semantic length (SSL (amount of semantic information required to perceive the incongruence of a sentence were modulated. Speech perception was explored with the N400 component of the event-related potentials recorded to sentence final words (50% semantically congruent with the sentence, 50% semantically incongruent. During sleep stage 2 and paradoxical sleep: (1 without noise, a larger N400 was observed for (short and long SSL sentences ending with a semantically incongruent word compared to a congruent word (i.e. an N400 effect; (2 with moderate noise, the N400 effect (observed at wake with short and long SSL sentences was attenuated for long SSL sentences. Our results suggest that WM for linguistic information is partially preserved during sleep with a smaller capacity compared to wake.

  12. Biologic comparison of partial breast irradiation protocols

    International Nuclear Information System (INIS)

    Rosenstein, Barry S.; Lymberis, Stella C.; Formenti, Silvia C.

    2004-01-01

    Purpose: To analyze the dose/fractionation schedules currently used in ongoing clinical trials of partial breast irradiation (PBI) by comparing their biologically effective dose (BED) values to those of three standard whole breast protocols commonly used after segmental mastectomy in the treatment of breast cancer. Methods and materials: The BED equation derived from the linear-quadratic model for radiation-induced cell killing was used to calculate the BEDs for three commonly used whole breast radiotherapy regimens, in addition to a variety of external beam radiotherapy, as well as high-dose-rate and low-dose-rate brachytherapy, PBI protocols. Results: The BED values of most PBI protocols resulted in tumor control BEDs roughly equivalent to a 50-Gy standard treatment, but consistently lower than the BEDs for regimens in which the tumor bed receives a total dose of either 60 Gy or 66 Gy. The BED values calculated for the acute radiation responses of erythema and desquamation were nearly all lower for the PBI schedules, and the late-response BEDs for most PBI regimens were in a similar range to the BEDs for the standard treatments. Conclusion: Biologically effective dose modeling raises the concern that inadequate doses might be delivered by PBI to ensure optimal in-field tumor control

  13. Extended abstract: Partial row projection methods

    Energy Technology Data Exchange (ETDEWEB)

    Bramley, R.; Lee, Y. [Indiana Univ., Bloomington, IN (United States)

    1996-12-31

    Accelerated row projection (RP) algorithms for solving linear systems Ax = b are a class of iterative methods which in theory converge for any nonsingular matrix. RP methods are by definition ones that require finding the orthogonal projection of vectors onto the null space of block rows of the matrix. The Kaczmarz form, considered here because it has a better spectrum for iterative methods, has an iteration matrix that is the product of such projectors. Because straightforward Kaczmarz method converges slowly for practical problems, typically an outer CG acceleration is applied. Definiteness, symmetry, or localization of the eigenvalues, of the coefficient matrix is not required. In spite of this robustness, work has generally been limited to structured systems such as block tridiagonal matrices because unlike many iterative solvers, RP methods cannot be implemented by simply supplying a matrix-vector multiplication routine. Finding the orthogonal projection of vectors onto the null space of block rows of the matrix in practice requires accessing the actual entries in the matrix. This report introduces a new partial RP algorithm which retains advantages of the RP methods.

  14. Silymarin Accelerates Liver Regeneration after Partial Hepatectomy

    Directory of Open Access Journals (Sweden)

    Jia-Ping Wu

    2015-01-01

    Full Text Available Partial hepatectomy (PHx is a liver regeneration physiological response induced to maintain homeostasis. Liver regeneration evolved presumably to protect wild animals from catastrophic liver loss caused by toxins or tissue injury. Silymarin (Sm ability to stimulate liver regeneration has been an object of curiosity for many years. Silymarin has been investigated for use as an antioxidant and anticarcinogen. However, its use as a supportive treatment for liver damage is elusive. In this study, we fed silymarin (Sm, 25 mg/kg to male Sprague-Dawley rats for 7 weeks. Surgical 2/3 PHx was then conducted on the rats at 6 hrs, 24 hrs, and 72 hrs. Western blot and RT-PCR were conducted to detect the cell cycle activities and silymarin effects on hepatic regeneration. The results showed that silymarin enhanced liver regeneration by accelerating the cell cycle in PHx liver. Silymarin led to increased G1 phase (cyclin D1/pRb, S phase (cyclin E/E2F, G2 phase (cyclin B, and M phase (cyclin A protein and mRNA at 6 hrs, 24 hrs, and 72 hrs PHx. HGF, TGFα, and TGFβ1 growth factor expressions were also enhanced. We suggest that silymarin plays a crucial role in accelerated liver regeneration after PHx.

  15. Turbulent flow in a partially filled pipe

    Science.gov (United States)

    Ng, Henry; Cregan, Hope; Dodds, Jonathan; Poole, Robert; Dennis, David

    2017-11-01

    Turbulent flow in a pressure driven pipe running partially full has been investigated using high-speed 2D-3C Stereoscopic Particle Imaging Velocimetry. With the field-of-view spanning the entire pipe cross section we are able to reconstruct the full three dimensional quasi-instantaneous flow field by invoking Taylor's hypothesis. The measurements were carried out over a range of flow depths at a constant Reynolds number based on hydraulic diameter and bulk velocity of Re = 32 , 000 . In agreement with previous studies, the ``velocity dip'' phenomenon, whereby the location of the maximum streamwise velocity occurs below the free surface was observed. A mean flow secondary current is observed near the free surface with each of the counter-rotating rollers filling the half-width of the pipe. Unlike fully turbulent flow in a rectangular open channel or pressurized square duct flow where the secondary flow cells appear in pairs about a corner bisector, the mean secondary motion observed here manifests only as a single pair of vortices mirrored about the pipe vertical centreline.

  16. Development of partial safety factors for the design of partially prestressed rectangular sections in biaxial flexure

    International Nuclear Information System (INIS)

    Chatterjee, Aritra; Bhattacharya, Baidurya; Agrawal, Gunjan; Mondal, Apurba

    2011-01-01

    Partial safety factors (PSFs) used in reliability-based design are intended to account for uncertainties in load, material and mathematical modeling while ensuring that the target reliability is satisfied for the relevant class of structural components in the given load combination and limit state. This paper describes the methodology in detail for developing a set of optimal reliability-based PSFs for the design of rectangular partially prestressed concrete sections subjected to biaxial flexure. The mechanical formulation of the flexural limit state is based on the principle behind prestressed concrete design recommended by IS 1343 and SP16 and failure is defined as tensile cracking of concrete extending beyond the depth of cover. The applied moments are combined according to Wood's criteria. The optimization of the PSFs is based on reliability indices obtained from first order reliability analysis of the structural components; Monte Carlo simulations are performed in each run to determine the capacity statistics and dependence between capacity and applied loads (effected through the axial loads influencing moment capacity corresponding to cracking). Numerical examples involving flexural design of partially prestressed concrete shell elements in nuclear power plant containments under accidental pressure load combination are provided. (author)

  17. Robot-assisted partial nephrectomy in contemporary practice

    Directory of Open Access Journals (Sweden)

    Youssef S. Tanagho

    2013-01-01

    Full Text Available Laparoscopic renal surgery is associated with reduced blood loss, shorter hospital stay, enhanced cosmesis, and more rapid convalescence relative to open renal surgery. Laparoscopic partial nephrectomy is a minimally invasive, nephron-sparing alternative to laparoscopic radical nephrectomy for the management of small renal masses. While offering similar oncological outcomes to laparoscopic radical nephrectomy, the technical challenges and prolonged learning curve associated with laparoscopic partial nephrectomy limit its wider dissemination. Robot-assisted partial nephrectomy, although still an evolving procedure with no long-term data, has emerged as a viable alternative to laparoscopic partial nephrectomy, with favorable preliminary outcomes. This article provides an overview of the role of robot-assisted partial nephrectomy in the management of renal cell carcinoma. The clinical indications and principles of surgical technique for this procedure are discussed. The oncological, renal functional, and perioperative outcomes of robot-assisted partial nephrectomy are also evaluated, as are complication rates.

  18. Performance of RC columns with partial length corrosion

    International Nuclear Information System (INIS)

    Wang Xiaohui; Liang Fayun

    2008-01-01

    Experimental and analytical studies on the load capacity of reinforced concrete (RC) columns with partial length corrosion are presented, where only a fraction of the column length was corroded. Twelve simply supported columns were eccentrically loaded. The primary variables were partial length corrosion in tensile or compressive zone and the corrosion level within this length. The failure of the corroded column occurs in the partial length, mainly developed from or located nearby or merged with the longitudinal corrosion cracks. For RC column with large eccentricity, load capacity of the column is mainly influenced by the partial length corrosion in tensile zone; while for RC column with small eccentricity, load capacity of the column greatly decreases due to the partial length corrosion in compressive zone. The destruction of the longitudinally mechanical integrality of the column in the partial length leads to this great reduction of the load capacity of the RC column

  19. Partial migration in fishes: definitions, methodologies and taxonomic distribution

    DEFF Research Database (Denmark)

    Chapman, B B; Skov, C; Hulthén, K

    2012-01-01

    published. In addition, previous work and synthesis has been hampered by a varied lexicon associated with this phenomenon in fishes. In this review, definitions and important concepts in partial migration research are discussed, and a classification system of the different forms of partial migration......Partial migration, where populations are composed of both migratory and resident individuals, is extremely widespread across the animal kingdom. Researchers studying fish movements have long recognized that many fishes are partial migrants, however, no detailed taxonomic review has ever been...... in fishes introduced. Next, a detailed taxonomic overview of partial migration in this group is considered. Finally, methodological approaches that ichthyologists can use to study this fascinating phenomenon are reviewed. Partial migration is more widespread amongst fishes than previously thought, and given...

  20. Partial Evaluation for Class-Based Object-Oriented Languages

    DEFF Research Database (Denmark)

    Schultz, Ulrik Pagh

    2001-01-01

    Object-oriented programming facilitates the development of generic software, but at a significant cost in terms of performance. We apply partial evaluation to object-oriented programs, to automatically map generic software into specific implementations. In this paper we give a concise, formal...... description of a simple partial evaluator for a minimal object-oriented language, and give directions for extending this partial evaluator to handle realistic programs....