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Sample records for decreased osmotic fragility

  1. Tirilazad mesylate protects stored erythrocytes against osmotic fragility.

    Science.gov (United States)

    Epps, D E; Knechtel, T J; Bacznskyj, O; Decker, D; Guido, D M; Buxser, S E; Mathews, W R; Buffenbarger, S L; Lutzke, B S; McCall, J M

    1994-12-01

    The hypoosmotic lysis curve of freshly collected human erythrocytes is consistent with a single Gaussian error function with a mean of 46.5 +/- 0.25 mM NaCl and a standard deviation of 5.0 +/- 0.4 mM NaCl. After extended storage of RBCs under standard blood bank conditions the lysis curve conforms to the sum of two error functions instead of a possible shift in the mean and a broadening of a single error function. Thus, two distinct sub-populations with different fragilities are present instead of a single, broadly distributed population. One population is identical to the freshly collected erythrocytes, whereas the other population consists of osmotically fragile cells. The rate of generation of the new, osmotically fragile, population of cells was used to probe the hypothesis that lipid peroxidation is responsible for the induction of membrane fragility. If it is so, then the antioxidant, tirilazad mesylate (U-74,006f), should protect against this degradation of stored erythrocytes. We found that tirilazad mesylate, at 17 microM (1.5 mol% with respect to membrane lecithin), retards significantly the formation of the osmotically fragile RBCs. Concomitantly, the concentration of free hemoglobin which accumulates during storage is markedly reduced by the drug. Since the presence of the drug also decreases the amount of F2-isoprostanes formed during the storage period, an antioxidant mechanism must be operative. These results demonstrate that tirilazad mesylate significantly decreases the number of fragile erythrocytes formed during storage in the blood bank.

  2. 21 CFR 864.6600 - Osmotic fragility test.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Osmotic fragility test. 864.6600 Section 864.6600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6600 Osmotic fragility...

  3. Improved Erythrocyte Osmotic Fragility and Packed Cell Volume ...

    African Journals Online (AJOL)

    Improved Erythrocyte Osmotic Fragility and Packed Cell Volume following administration of Aloe barbadensis Juice Extract in Rats. ... Abstract. Aloe barbadensis is a popular house plant that has a long history of a multipurpose folk remedy. ... Keywords: osmotic fragility, packed cell volume, haemoglobin, Aloe vera ...

  4. The osmotic fragility of human erythrocytes is inhibited by laser irradiation

    International Nuclear Information System (INIS)

    Habodaszova, D.; Sikurova, L.; Waczulikova, I.

    2004-01-01

    In this study we investigated the influence of green laser irradiation (532 nm, 30 mW, 31,7 J/cm 2 ) on the membrane integrity of human erythrocytes and compared the results with the effect of infrared laser irradiation (810 nm, 50 mW, 31,3 J/cm 2 ). To evaluate the membrane integrity of erythrocytes, one clinical parameter, the osmotic fragility, was investigated. We observed a decrease in osmotic fragility of the erythrocytes after irradiation by the green laser light as well as by the infrared laser compared to non-irradiated controls (Authors)

  5. THE IMPORTANCE OF THE ERYTHROCYTES OSMOTIC FRAGILITY TEST PERFORMED IN CHILDREN WITH INDIRECT HYPERBILIRUB1NEMIA

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    Ivana Stojanović

    2005-07-01

    Full Text Available The osmotic fragility test of erythrocytes is useful in the diagnosis of different types of hereditary hemolytic anemias followed with hyperbilirubinemia. Hemolytic anemias, characterized by accelerated destruction of red blood cells, are usually the consequence of many metabolic abnormalities like cellular membrane defect, erythrocyte enzymes defect or hemoglobin abnormalities – hemoglobinopathies. The object of our study was to assess the relationship between osmotic fragility test of erythrocytes and severity of indirect hyperbilirubinemia in some inherited erythrocytes’ disorders. We did the osmotic fragility test of erythrocytes by using Dacie, s method with normal values of erythrocytes hemolysis between 0,48 to 0,34% NaCl (minimal to maximal hemolysis. In hereditary spherocytosis, fragility of erythrocytes was increased (min. at 0,50 % NaCl to max. 0,44 % NaCl . In the child with β- thalassemia and cycle cell anemia erythrocytes fragility was decreased (min . at 0,42 to max. 0,32 % NaCl, that is 0,40% min. of hemolysis and 0,34% max. hemolysis in the second case. In newborn infants with high levels of indirect bilirubin in serum as a cause of physiological jaundice, the osmotic fragility test was within a normal range. Our findings point out the diagnostic value of osmotic fragility test in assessing patients with the indirect hyperbilirubinemia. This simple and important diagnostic test can be performed in small laboratories.

  6. Flow cytometric osmotic fragility test and eosin-5'-maleimide dye-binding tests are better than conventional osmotic fragility tests for the diagnosis of hereditary spherocytosis.

    Science.gov (United States)

    Arora, R D; Dass, J; Maydeo, S; Arya, V; Radhakrishnan, N; Sachdeva, A; Kotwal, J; Bhargava, M

    2018-03-24

    Hereditary spherocytosis (HS) is the most common inherited hemolytic anemia with heterogeneous clinico-laboratory manifestations. We evaluated the flow-cytometric tests: eosin-5'-maleimide (EMA) and flow-cytometric osmotic fragility test (FOFT) and the conventional osmotic fragility tests (OFT) for the diagnosis of hereditary spherocytosis (HS). One hundred two suspected HS patients underwent EMA, FOFT, incubated OFT (IOFT), and room temperature OFT (RT-OFT). In addition, 10 cases of immune hemolytic anemia (IHA) were included, and performance of the above 4 tests was evaluated. For EMA and FOFT, 5 normal controls were assessed together with the patients and cutoffs were calculated using receiver-operator-characteristics curve (ROC) analysis. The best cutoff for %EMA decrease was 12.5%, and for FOFT, %residual red cells (%RRC) was 25.6%. The sensitivity and specificity of RT-OFT was 62.06% and 86.3%, respectively, while that of IOFT was 79.31% and 87.67%, respectively. Both flow cytometric tests performed better. Sensitivity and specificity of EMA was 86.2% and 93.9% respectively, and that of FOFT was 96.6% and 98.63%, respectively. The combination of the FOFT with IOFT or EMA dye-binding test yields a sensitivity of 100%, but with EMA, it had a higher specificity. Hb/MCHC was a predictor of the severity of the disease while %EMA decrease and %RRC did not correlate with severity of the disease. Flow-cytometric osmotic fragility test is the best possible single test followed by EMA for diagnosis of HS. A combination of FOFT and EMA can correctly diagnose 100% patients. These tests are likely to replace conventional OFTs in future. © 2018 John Wiley & Sons Ltd.

  7. Comparative Erythrocytes Osmotic Fragility Test and some ...

    African Journals Online (AJOL)

    Erythrocytes osmotic fragility and haematological parameters of subjects with HbAS (sickle cell trait) and HbSS (sickle cell anaemia) were determined and compared with subjects with HbAA (normal adult haemoglobin), which acted as control. They were divided into three groups of 40 subjects for HbAA, 35 subjects for ...

  8. Assessment of effects of a formula used in the traditional Chinese medicine (Buzhong Yi Qi Wan on the morphologic and osmotic fragility of red blood cells

    Directory of Open Access Journals (Sweden)

    Tania S. Giani

    Full Text Available Buzhong Yi Qi Wan (BYQW is a combination of some medicinal herbs widely used in traditional Chinese medicine to treat blood, spleen and stomach disorders. Morphometric analysis and osmotic fragility assay have been used to evaluate changes on membrane integrity of red blood cells. The aim of this work was to evaluate the effect of an aqueous BYQW extract on the morphology and osmotic fragility of red blood cells. Blood samples were treated with BYQW extract, quantitative/qualitative morphological analysis and osmotic fragility assay were carried out against control groups treated with saline. The data obtained indicated no modification on morphology but osmotic fragility assay suggested a significant (p<0.05 increasing of hemolysis in red blood cells isolated from blood treated with aqueous BYQW extract. In conclusion, the aqueous BYQW extract could affect the membrane integrity decreasing the osmotic resistance but without altering the shape of red blood cells.

  9. Ebselen exhibits glycation-inhibiting properties and protects against osmotic fragility of human erythrocytes in vitro.

    Science.gov (United States)

    Soares, Julio C M; Folmer, Vanderlei; Da Rocha, João B T; Nogueira, Cristina W

    2014-05-01

    Diabetic status is associated with an increase on oxidative stress markers in humans and animal models. We have investigated the in vitro effects of high concentrations of glucose on the profile of oxidative stress and osmotic fragility of blood from control and diabetic patients; we considered whether its antioxidant properties could afford some protection against glucose-induced osmotic fragility, and whether ebselen could act as an inhibitor of hemoglobin glycation. Raising blood glucose to 5-100 mmol/L resulted in a concentration-dependent increase of glycated hemoglobin (HbA1c; P Ebselen significantly reduced the glucose-induced increase in osmotic fragility and inhibited HbA1c formation (P < 0.0001). These results indicate that blood from patients with uncontrolled diabetes are more sensitive to osmotic shock than from patients with controlled diabetes and control subjects in relation to increased production of free radicals in vivo. © 2014 International Federation for Cell Biology.

  10. Decreased erytrocyte osmotic fragility during canine leptospirosis Diminuição da fragilidade osmótica eritrocitária na leptospirose canina

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    Marcelo L. Santoro

    1994-02-01

    Full Text Available Erythrocyte osmotic fragility (EOF was carried out in nineteen dogs naturally infected by Leptospira interrogans serovar icterohaemorrhagiae/copenhagi. A decreased EOF was observed, suggesting a modification of erythrocyte components secondary to disturbances that occur during canine leptospirosis, such as renal damage and hepatic disease.A fragilidade osmótica eritrocitária foi estudada em dezenove cães infectados naturalmente pela Leptospira interrogans serovar icterohaemorrhagiae/copenhagi. Observou-se uma redução da fragilidade osmótica eritrocitária, sem a presença de anemia, possivelmente relacionada aos distúrbios hepato-renais que ocorrem nesta patologia.

  11. Effects of an angelica extract on human erythrocyte aggregation, deformation and osmotic fragility.

    Science.gov (United States)

    Wang, X; Wei, L; Ouyang, J P; Muller, S; Gentils, M; Cauchois, G; Stoltz, J F

    2001-01-01

    In Chinese traditional medicine, angelica is widely used for its known clinical effects of ameliorating blood microcirculation. But the mechanism of these beneficial effects still remains unclear. In this work the rheological behaviour of human erythrocytes treated by angelica was studied in vitro. Normal RBCs incubated with an angelica extract at different concentrations (5, 10 or 20 mg/ml) for 60 min at 37 degrees C and then their aggregation, deformation and osmotic fragility were measured with different recently developed optical techniques, namely Erythroaggregometer (Regulest, Florange, France), LORCA (Mechatronics, Amsterdam) and Fragilimeter (Regulest, Florange, France). Experimental results show that angelica (20 mg/ml) significantly decreased normal RBCs' aggregation speed (p<0.01) and could inhibit the hyperaggregability caused by dextran 500. However, the strength of normal RBCs aggregates were not influenced by angelica. When a calcium ionophore A23187 (1.9 microM) was used to harden cell membrane, angelica (20 mg/ml) could significantly (p<0.01) protect erythrocytes against the loss of their deformability even it had no effects on normal RBCs deformation. Finally angelica (5 and 10 mg/ml) decreased significantly (p<0.01) normal RBCs osmotic fragility. In conclusion angelica plays a rheologically active role on human erythrocytes, and this study suggests a possible mechanism for angelica's positive effects against certain cardiovascular diseases.

  12. Effect of road transport stress on Erthrocyte Osmotic Fragility (EOF ...

    African Journals Online (AJOL)

    After an overnight fast, venous blood was collected from each subject for the determination of serum cortisol, glucose concentration and erythrocyte osmotic fragility. The subjects were then transported at a speed of 65 – 75Km/h covering a distance of 180km. Thereafter venous blood was again collected (within 10 minutes) ...

  13. The approximate entropy of the electromyographic signals of tremor correlates with the osmotic fragility of human erythrocytes

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    Penha-Silva Nilson

    2010-06-01

    Full Text Available Abstract Background The main problem of tremor is the damage caused to the quality of the life of patients, especially those at more advanced ages. There is not a consensus yet about the origins of this disorder, but it can be examined in the correlations between the biological signs of aging and the tremor characteristics. Methods This work sought correlations between the osmotic fragility of erythrocytes and features extracted from electromyographic (EMG activity resulting from physiological tremor in healthy patients (N = 44 at different ages (24-87 years. The osmotic fragility was spectrophotometrically evaluated by the dependence of hemolysis, provided by the absorbance in 540 nm (A54o, on the concentration of NaCl. The data were adjusted to curves of sigmoidal regression and characterized by the half transition point (H50, amplitude of lysis transition (dx and values of A540 in the curve regions that characterize the presence of lysed (A1 and preserved erythrocytes (A2. The approximate entropy was estimated from EMG signals detected from the extensor carpi ulnaris muscle during the movement of the hand of subjects holding up a laser pen towards an Archimedes spiral, fixed in a whiteboard. The evaluations were carried out with the laser pen at rest, at the center of the spiral, and in movement from the center to the outside and from outside to the center. The correlations among the parameters of osmotic fragility, tremor and age were tested. Results Negative correlations with age were found for A1 and dx. With the hand at rest, a positive correlation with H50 was found for the approximate entropy. Negative correlations with H50 were found for the entropy with the hand in movement, as from the center to the outside or from the outside to the center of the spiral. Conclusion In healthy individuals, the increase in the erythrocyte osmotic fragility was associated with a decrease in the approximate entropy for rest tremor and with an increase

  14. Oral supplementation of vitamin E reduces osmotic fragility of RBC in hemolytic anemic patients with G6PD deficiency

    International Nuclear Information System (INIS)

    Sultana, N.; Begum, S.; Begum, N.; Ali, T.

    2009-01-01

    haemolytic anaemia due to G6PD deficiency in comparison to those of the healthy control. After supplementation with vitamin E starting and completing points of osmotic fragility of RBC were significantly decreased whereas, MCV, MCH, MCHC were significantly increased towards those of healthy of healthy control in supplemented group of patients in comparison to those of their pre-supplemented (day-1) and non-supplemented groups both on day 1 and day 60. From this study it may be concluded that, disturbances of some of the haematological parameter like higher osmotic fragility of RBC and lower MCV, MCH, MCHC occur in G6PD deficient haemolytic anaemic patients, which returned towards normal after supplementation of vitamin E, which clearly indicates? the role of this anti-oxidant vitamin in maintaining red cell membrane integrity and thereby decreases the rate of haemolysis in this group of patients. So, vitamin E can be supplemented along with other drugs for better management of the patients. (author)

  15. Hematology and erythrocyte osmotic fragility of the Franquet's fruit bat (Epomops franqueti).

    Science.gov (United States)

    Ekeolu, Oyetunde Kazeem; Adebiyi, Olamide Elizabeth

    2018-03-15

    Hematological parameters are vital diagnostic tools for understanding health dynamics of humans and animals. Franquet's fruit bat (Epomops franqueti) is host to several parasites such as protozoa, bacteria, viruses and mites. Yet, studies exploring the values of its blood components with interest for research or food purposes are scarce. Thus, this study was carried out to investigate the hematological values of the adult E. franqueti. Seventeen (nine female and eight male) apparently healthy adult E. franqueti were captured from their roosting colony. Blood samples were collected for determination of erythrocyte indices [red blood cell count (RBC), packed cell volume (PCV), hemoglobin (Hb) concentration, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC)] and leukocyte indices [total white blood cell counts (WBC), lymphocytes, eosinophil, monocytes, neutrophil count and erythrocytes osmotic fragility]. There were no significant (p≥0.05) sex-related differences in RBC, PCV, Hb concentration, MCV, MCH, MCHC and total and differential WBC of E. franqueti. Erythrocyte osmotic fragility was significantly higher in female than in male E. franqueti at 0.1% NaCl. These considerations are critical in establishing reference ranges of blood parameters for E. franqueti and may provide insight to why they serve as reservoir hosts for several microorganisms.

  16. Effects of Momordica charantia on osmotic fragility and label red blood cells and plasmatic protein with 99m-Tc in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Magnata, Simey S.L.P. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Energia Nuclear]. E-mail: sfmagnata@terra.com.br; Correia, Marilia B.L.; Brandao, Jose Odinilson C.; Souza, Grace M.L.; Catanho, Maria Teresa J.A. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia; Terra, Daniele A.; Amorim, Lucia F. [Rio Grande do Norte Univ., Natal, RN (Brazil). Dept. de Fisiologia

    2005-07-01

    The use of natural products in the treatment physiopathology awaken the interest in the inquiry of the action mechanisms. The Momordica charantia, Melao de Sao Caetano, is used in the Caribbean and Orient for the diseases as stomatitis, cancer and diabetes. This work aims to verify the effect of the Momordica charantia's aqueous extract leaves on osmotic fragility and on labeling red blood cells (RBC) and plasmatic proteins with {sup 99m}Tc in vitro. To evaluate the osmotic fragility, samples of heparinized blood (500 mL) was incubed for 1 hour with brut extract (500 mL) in different concentrations (0; 10; 50 and 100% v/v); after centrifugation, the RCB were submitted the incubation (1 hour) with a gradient of NaCl (0;0,1;0,25;0,4;0,7 and 0.9%), the OD of supernatant was determined. With regards to label red blood cells and plasmatic proteins with {sup 99m}Tc in vitro was carried out by incubating of anticoagulant whole blood (500 mL) for 1 hour with brut extract (500 mL) in different concentrations (0; 10; 50 and 100% v/v). A stannous chloride solution of 1,2 {mu}g/mL was added the incubation for 60 minutes. After this the {sup 99m}Tc (3,7 MBq) was added and the incubation was continued for another 10 minutes. Those were centrifuged, precipitated with trichloroacetic acid 5% and mensured in a counter. The results shows that with regard to osmotic fragility, only the extract in the concentration of 100% provoked hemolysis. The Momordica charantia's extract is an agent who modify the fixation of {sup 99m}Tc in red blood cells. The results show with regard to osmotic fragility, only the extract in the quantity 100% provoked hemolysis. It is concluded that the Momordica charantia's extract is an agent who unchains the cellular fragility and {sup 99m}Tc fixation, showing a reduction effect. (author)

  17. Effects of Momordica charantia on osmotic fragility and label red blood cells and plasmatic protein with 99m-Tc in vitro

    International Nuclear Information System (INIS)

    Magnata, Simey S.L.P.; Correia, Marilia B.L.; Brandao, Jose Odinilson C.; Souza, Grace M.L.; Catanho, Maria Teresa J.A.; Terra, Daniele A.; Amorim, Lucia F.

    2005-01-01

    The use of natural products in the treatment physiopathology awaken the interest in the inquiry of the action mechanisms. The Momordica charantia, Melao de Sao Caetano, is used in the Caribbean and Orient for the diseases as stomatitis, cancer and diabetes. This work aims to verify the effect of the Momordica charantia's aqueous extract leaves on osmotic fragility and on labeling red blood cells (RBC) and plasmatic proteins with 99m Tc in vitro. To evaluate the osmotic fragility, samples of heparinized blood (500 mL) was incubed for 1 hour with brut extract (500 mL) in different concentrations (0; 10; 50 and 100% v/v); after centrifugation, the RCB were submitted the incubation (1 hour) with a gradient of NaCl (0;0,1;0,25;0,4;0,7 and 0.9%), the OD of supernatant was determined. With regards to label red blood cells and plasmatic proteins with 99m Tc in vitro was carried out by incubating of anticoagulant whole blood (500 mL) for 1 hour with brut extract (500 mL) in different concentrations (0; 10; 50 and 100% v/v). A stannous chloride solution of 1,2 μg/mL was added the incubation for 60 minutes. After this the 99m Tc (3,7 MBq) was added and the incubation was continued for another 10 minutes. Those were centrifuged, precipitated with trichloroacetic acid 5% and mensured in a counter. The results shows that with regard to osmotic fragility, only the extract in the concentration of 100% provoked hemolysis. The Momordica charantia's extract is an agent who modify the fixation of 99m Tc in red blood cells. The results show with regard to osmotic fragility, only the extract in the quantity 100% provoked hemolysis. It is concluded that the Momordica charantia's extract is an agent who unchains the cellular fragility and 99m Tc fixation, showing a reduction effect. (author)

  18. The influence of increased hepatic sequestration after splenectomy on the survival and osmotic fragility of red cells in rats, with reference to protein levels in diets

    International Nuclear Information System (INIS)

    Hisaoka, Fumiko; Shiraki, Keizo; Sagawa, Sueko

    1977-01-01

    The sequestration of erythrocytes in rats was studied using an isologous 51-Cr labeled population of either normal or N-ethyl-maleimide treated red cells. Experiments were performed for observing the effects of the change in the hepatic sequestration of altered red cells on the osmotic fragility and the survival time of circulating red cells. The rate of sequestration in liver at different period after splenectomy was measured with respect to the survival time and osmotic fragility of red cells. The parameters of the proliferative response imposed on liver were also observed. The spleen sequestered selectively damaged red cells, while the liver compensated and overshot the sequestration for spleen after splenectomy. The sequestering response in liver increased gradually and reached the maximum level around 8 weeks after splenectomy, and then declined toward the control level. This compensatory response in liver was not observed in the rats fed with low protein diet. Therefore, the proliferative response imposed on liver by an extra work after splenectomy was not stimulated in the rats fed with low protein diet. Splenectomy prolonged erythrocyte survival and reduced the osmotic fragility of normal red cells, but the compensatory increase in the sequestration of damaged red cells in liver did not alter the survival and osmotic fragility of normal red cells. This fact indicates that the increased sequestration of reticuloendothelial cells in liver is basically reparative, and it is impossible to compensate for the absence of the spleen because of the inability to duplicate certain anatomic features peculiar to the spleen. (Iwakiri, K.)

  19. Influence of some DNA-alkylating drugs on thermal stability, acid and osmotic resistance of the membrane of whole human erythrocytes and their ghosts.

    Science.gov (United States)

    Ivanov, I T; Gadjeva, V

    2000-09-01

    Human erythrocytes and their resealed ghosts were alkylated under identical conditions using three groups of alkylating antitumor agents: mustards, triazenes and chloroethyl nitrosoureas. Osmotic fragility, acid resistance and thermal stability of membranes were changed only in alkylated ghosts in proportion to the concentration of the alkylating agent. All the alkylating agents decreased acid resistance in ghosts. The clinically used drugs sarcolysine, dacarbazine and lomustine all decreased osmotic fragility and thermal stability of ghost membranes depending on their lipophilicity. DM-COOH did not decrease osmotic fragility and thermal stability of ghost membranes, while NEM increased thermal stability of membranes. The preliminary but not subsequent treatment of ghosts with DM-COOH fully abolished the alkylation-induced thermal labilization of ghost membrane proteins while NEM had a partial effect only. The present study gives direct evidence that alkylating agents, having a high therapeutic activity against malignant growth, bind covalently to proteins of cellular membranes.

  20. Effect of packing on changes in erythrocyte osmotic fragility and malondialdehyde concentration in donkeys administered with ascorbic acid

    OpenAIRE

    Folashade Olaifa; Joseph O. Ayo; Suleiman F. Ambali; Peter I. Rekwot

    2012-01-01

    Experiments were performed with the aim of investigating the effect of packing on erythrocyte osmotic fragility (EOF) and malondialdehyde (MDA) concentration in donkeys, and the effect of ascorbic acid (AA). Twelve apparently healthy donkeys raised under the traditional extensive system served as experimental subjects. Six donkeys administered orally with AA (200 mg/kg) and subjected to packing were used as experimental animals, whilst six others not administered with AA served as contro...

  1. Erythrocyte osmotic fragility and lipid peroxidation following chronic co-exposure of rats to chlorpyrifos and deltamethrin, and the beneficial effect of alpha-lipoic acid

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    Chidiebere Uchendu

    2014-01-01

    Full Text Available The present study aimed to evaluate the effect of chronic co-exposure to chlorpyrifos (CPF and deltamethrin (DLT on erythrocyte osmotic fragility, lipid peroxidation and the ameliorative effect of alpha-lipoic acid (ALA on erythrocyte fragility. Thirty-six male Wistar rats divided into six groups of six rats each were used for the study. Groups I (S/oil and II (ALA were given soya oil (2 ml/kg and ALA (60 mg/kg, respectively. Rats in group III (DLT and IV (CPF were exposed to DLT (6.25 mg/kg and CPF (4.75 mg/kg (1/20th of the previously determined LD50 of 125 mg/kg and 95 mg/kg, respectively, over a period of 48 h. Rats in group V (CPF + DLT were co-exposed to CPF (4.75 mg/kg and DLT (6.25 mg/kg, while those in group VI (ALA + CPF + DLT were pretreated with ALA (60 mg/kg and then co-exposed to CPF and DLT, 45 min later. The treatments were administered by gavage once daily for a period of 16 weeks. Blood collected at the end of the experimental period were analyzed for erythrocyte osmotic fragility and malondialdehyde (MDA concentration. The study showed that chronic co-exposure to CPF and DLT resulted in an increase in erythrocyte fragility and MDA concentration which were ameliorated by supplementation with alpha-lipoic acid. The study concluded that repeated co-exposure to CPF and DLT elevated erythrocyte fragility probably due to increased lipid peroxidation, and pretreatment with alpha-lipoic acid ameliorated these alterations.

  2. Comparison of intraerythrocyte and intraleucocyte Sodium content and erythrocyte fragility in normotensive subjects

    International Nuclear Information System (INIS)

    Paci, A.; Cocci, F.; Cristofani, R.; Piras, F.; Balzan, S.; Mezzasalma, L.; Ghione; Giachetti, M.

    1988-01-01

    The Sodium content of mononuclear leucocytes and erythrocytes and the osmotic fragility of erythrocytes were measured in 22 young male volunteers before and after three days of increased Sodium intake. Analysis of variance for repeated measurements showed no significant correlations between intraleucocyte and intraerythrocyte Sodium and between intraerythrocyte Sodium and osmotic fragility. On the other hand, a highly significant relation was present between osmotic fragility and intraleucocyte Sodium before high salt intake, which disappeared after 3 days of increased salt intake

  3. Quantified Effects of Late Pregnancy and Lactation on the Osmotic ...

    African Journals Online (AJOL)

    Quantified Effects of Late Pregnancy and Lactation on the Osmotic Stability of ... in the composition of erythrocyte membranes associated with the physiologic states. Keywords: Erythrocyteosmotic stability, osmotic fragility, late pregnancy, ...

  4. Effects of pesticides on the osmotic fragility of erythrocytes – A brief review.

    Directory of Open Access Journals (Sweden)

    Humberto Gabriel Rodrigues

    2009-03-01

    Full Text Available Despite their applications in other fields, agriculture is the main source of environmental contamination by pesticides. Pesticides and their metabolites have been found in the oceans, soil and atmosphere, and are probably responsible for the loss of biodiversity and deterioration of the natural environment. Roundup® is the pesticide most used in Brazil. Recents studies have demonstrated that ghyphosate (the main ingredient of Roundup®, while considered to be of low risk, generates osmotic fragility at the concentrations recommended by the manufactures. The problems caused by this pesticide can be explained by hypoxia caused by hemolysis of erythrocytes. Such pesticides can be associated with the acquisition of dementia. With the growth of populational aging rates in Brazil, the time-dependent contact of individuals with dangerous substances is correspondingly greater, and putatively, the growth of dementia caused by exogenous factors also increase. Contamination of the environment by pesticides and the diseases provoked by them can therefore be considered to constitute a problem of public health.

  5. The use of the rapid osmotic fragility test as an additional test to diagnose canine immune-mediated haemolytic anaemia

    DEFF Research Database (Denmark)

    Paes, Geert; Paepe, Dominique; Meyer, Evelyne

    2013-01-01

    Background: Diagnosing canine immune-mediated haemolytic anaemia (IMHA) is often challenging because all currently available tests have their limitations. Dogs with IMHA often have an increased erythrocyte osmotic fragility (OF), a characteristic that is sometimes used in the diagnosis of IMHA...... hyperlipemic dogs (group 3), 10 dogs with lymphoma (group 4), 8 dogs with an infection (group 5) and 13 healthy dogs (group 6) were included. In all dogs, blood smear examination, in-saline auto-agglutination test, Coombs' test, COFT and ROFT were performed. In the COFT, OF5, OF50 and OF90 were defined...

  6. Phenotypic variations in osmotic lysis of Sahel goat erythrocytes in non-ionic glucose media.

    Science.gov (United States)

    Igbokwe, Nanacha Afifi; Igbokwe, Ikechukwu Onyebuchi

    2016-03-01

    Erythrocyte osmotic lysis in deionised glucose media is regulated by glucose influx, cation efflux, and changes in cell volume after water diffusion. Transmembrane fluxes may be affected by varied expression of glucose transporter protein and susceptibility of membrane proteins to glucose-induced glycosylation and oxidation in various physiologic states. Variations in haemolysis of Sahel goat erythrocytes after incubation in hyposmotic non-ionic glucose media, associated with sex, age, late pregnancy, and lactation, were investigated. The osmotic fragility curve in glucose media was sigmoidal with erythrocytes from goats in late pregnancy (PRE) or lactation (LAC) or from kid (KGT) or middle-aged (MGT) goats. Non-sigmoidal phenotype occurred in yearlings (YGT) and old (OGT) goats. The composite fragility phenotype for males and non-pregnant dry (NPD) females was non-sigmoidal. Erythrocytes with non-sigmoidal curves were more stable than those with sigmoidal curves because of inflectional shift of the curve to the left. Erythrocytes tended to be more fragile with male than female sex, KGT and MGT than YGT and OGT, and LAC and PRE than NPD. Thus, sex, age, pregnancy, and lactation affected the haemolytic pattern of goat erythrocytes in glucose media. The physiologic state of the goat affected the in vitro interaction of glucose with erythrocytes, causing variations in osmotic stability with variants of fragility phenotype. Variations in the effect of high extracellular glucose concentrations on the functions of membrane-associated glucose transporter, aquaporins, and the cation cotransporter were presumed to be relevant in regulating the physical properties of goat erythrocytes under osmotic stress.

  7. Low Red Blood Cell Vitamin C Concentrations Induce Red Blood Cell Fragility: A Link to Diabetes Via Glucose, Glucose Transporters, and Dehydroascorbic Acid

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    Hongbin Tu

    2015-11-01

    Full Text Available Strategies to prevent diabetic microvascular angiopathy focus on the vascular endothelium. Because red blood cells (RBCs are less deformable in diabetes, we explored an original concept linking decreased RBC deformability to RBC ascorbate and hyperglycemia. We characterized ascorbate concentrations from human and mouse RBCs and plasma, and showed an inverse relationship between RBC ascorbate concentrations and deformability, measured by osmotic fragility. RBCs from ascorbate deficient mice were osmotically sensitive, appeared as spherocytes, and had decreased β-spectrin. These aberrancies reversed with ascorbate repletion in vivo. Under physiologic conditions, only ascorbate's oxidation product dehydroascorbic acid (DHA, a substrate for facilitated glucose transporters, was transported into mouse and human RBCs, with immediate intracellular reduction to ascorbate. In vitro, glucose inhibited entry of physiologic concentrations of dehydroascorbic acid into mouse and human RBCs. In vivo, plasma glucose concentrations in normal and diabetic mice and humans were inversely related to respective RBC ascorbate concentrations, as was osmotic fragility. Human RBC β-spectrin declined as diabetes worsened. Taken together, hyperglycemia in diabetes produced lower RBC ascorbate with increased RBC rigidity, a candidate to drive microvascular angiopathy. Because glucose transporter expression, DHA transport, and its inhibition by glucose differed for mouse versus human RBCs, human experimentation is indicated.

  8. Erythrocyte Osmotic Fragility and Excitability Score in Rabbit fed ...

    African Journals Online (AJOL)

    olayemitoyin

    protect cells against oxidative stress in rats (Wang et al., 2000) and ... method, total red blood cell (RBC) count, total leukocyte (WBC) count .... maturative stages of the erythroblast (pluripotent stem cells) involved in cell formation (Kaur and. Kapoor, 2005). ... effect of zinc on chlorpyrifos- induced erythrocyte fragility in wistar ...

  9. Decreased level of 2,3-diphosphoglycerate and alteration of structural integrity in erythrocytes infected with Plasmodium falciparum in vitro.

    Science.gov (United States)

    Dubey, M L; Hegde, Ramakrishna; Ganguly, N K; Mahajan, R C

    2003-04-01

    2,3-Diphosphoglycerate (2,3-DPG), an intracellular metabolite of glycolytic pathway is known to affect the oxygen binding capacity of haemoglobin and mechanical properties of the red blood cells. 2,3-DPG levels have been reported to be elevated during anaemic conditions including visceral leishmaniasis. 2,3-DPG activity in P. falciparum infected red blood cells, particularly in cells infected with different stages of the parasite and its relationship with structural integrity of the cells is not known. Chloroquine sensitive and resistant strains of P. falciparum were cultured in vitro and synchronized cultures of ring, trophozoite and schizont stage rich cells along with the uninfected control erythrocytes were assayed for 2,3-DPG activity and osmotic fragility. It was observed that in both the strains, in infected erythrocytes the 2,3-DPG activity gradually decreased and osmotic fragility gradually increased as the parasite matured from ring to schizont stage. The decrease in 2,3-DPG may probably be due to increased pyruvate kinase activity of parasite origin, which has been shown in erythrocytes infected with several species of Plasmodium. The absence of compensatory increase in 2,3-DPG in P. falciparum infected erythrocytes may aggravate hypoxia due to anaemia in malaria and probably may contribute to hypoxia in cerebral malaria. As 2,3-DPG was not found to be increased in erythrocytes parasitized with P. falciparum, the increased osmotic fragility observed in these cells is not due to increased 2,3-DPG as has been suggested in visceral leishmaniasis.

  10. Effect of packing on changes in erythrocyte osmotic fragility and malondialdehyde concentration in donkeys administered with ascorbic acid.

    Science.gov (United States)

    Olaifa, Folashade; Ayo, Joseph O; Ambali, Suleiman F; Rekwot, Peter I

    2012-12-05

    Experiments were performed with the aim of investigating the effect of packing on erythrocyte osmotic fragility (EOF) and malondialdehyde (MDA) concentration in donkeys, and the effect of ascorbic acid (AA). Twelve apparently healthy donkeys raised under the traditional extensive system served as experimental subjects. Six donkeys administered orally with AA (200 mg/kg) and subjected to packing were used as experimental animals, whilst six others not administered with AA served as controls. Blood samples were collected pre- and post-packing from all the donkeys for the determination of MDA and EOF. At 0.3% Sodium Chloride (NaCl) concentration, the percentage haemolysis was 93.69% ± 2.21% in the control donkeys and the value was significantly (P < 0.05) higher than the value of 71.31% ± 8.33%, recorded in the experimental donkeys. The post-packing MDA concentration obtained in the control donkeys was 39.62 µmol ± 4.16 µmol, and was not significantly different (P > 0.05) from the value of 35.97 µmol ± 2.88 µmol recorded in the experimental donkeys. In conclusion, the increase in haemolysis obtained in the donkeys suggested that packing induced oxidative stress, which was ameliorated by AA administration.

  11. Erythrocyte Osmotic Fragility and Excitability Score in Rabbit fed Hibiscus Sabdariffa in Graded Level.

    Science.gov (United States)

    Adenkola, A Y; Oluremi, O I A

    2014-12-29

    This study was conducted for 10 weeks with the aim of investigating the erythrocyte membrane integrity as measured by erythrocyte osmotic fragility and excitability scores of rabbits fed graded level of Hibiscus sabdariffa calyx (HSC). Twenty weaners' rabbit of both sexes were used for the study and were placed on four experimental diets which contain the following percentages of HSC 0 %, 25 %, 50 %, 75 %, as feed additive and were added at 0 g, 62.5 g, 125 g, 187.5 g designated as T1, T2, T3 and T4 experimental diets. Excitability scores were measured weekly as described by Voisnet et al. (1997). At the end of the experiment, the rabbits were slaughtered by severing the jugular vein. A Blood sample (2 ml) was collected from each rabbit into sampled bottles, containing the Na EDTA as anticoagulant for hematological analysis. Packed cell volume (PCV) Haemoglobin concentration (Hb), Total red blood cell (RBC) count, Total leukocyte count as well as differential leukocyte was determined using standard method. The percentage haemolysis recorded at 0.3 % to 0.8 % was significantly (P < 0.05) higher in rabbits in T1 compared to the remaining 3 diets. The result of excitability score shows that rabbit on diet 1 and 2 had a lower value which was significantly (P < 0.05) lower than rabbits on diets 3 and 4 with a value of 65.5 ± 5.0 and 70.00 ± 5.50 % respectively. In conclusion this study demonstrated for the first time that chronic administration of HSC improves haematological parameters, brain mood and function as well as maintaining erythrocyte membrane integrity.

  12. Cryohemolysis, erythrocyte osmotic fragility, and supplementary hematimetric indices in the diagnosis of hereditary spherocytosis.

    Science.gov (United States)

    Emilse, Ledesma Achem Miryam; Cecilia, Haro; María, Terán Magdalena; Eugenia, Mónaco María; Alicia, Issé Blanca; Lazarte, Sandra Stella

    2018-03-01

    Hereditary spherocytosis (HS) is a chronic hemolytic anemia characterized by microspherocytes in the peripheral blood and increased erythrocyte osmotic fragility (EOF). This study evaluated the cryohemolysis test (CHT); initial hemolysis (IH); immediate and incubated hemolysis percentage in 5.5 g/L NaCl (H5.5); mean corpuscular hemoglobin concentration (MCHC); red blood cell distribution width (RDW); and Hb/MCHC, Hb/RDW, and MCHC/RDW ratios for the diagnosis of HS. Data from 13 patients with HS were evaluated at the Instituto de Bioquímica Aplicada and compared with data from 14 unaffected individuals and 11 patients with anemia due to another etiology. Total blood and reticulocyte counts, CHT, and immediate and incubated EOF were performed in all subjects; sensitivity, specificity, efficiency, and Youden index (YI) were calculated. Eight patients with HS had MCHC ≥345 g/L, 10 had RDW ≥14.5%, 12 had IH >5.0 g/L, 11 had immediate H5.5 ≥5%, and 13 had incubated H5.5 ≥50% (the cut-off value to consider HS). The efficiency and YI were: immediate H5.5 (0.94-0.85), incubated H5.5 (0.89-0.82), IH (0.89-0.78), MCHC (0.87-0.62), CHT (0.84-0.54), and Hb/MCHC (0.71-0.56), respectively. The calculated ratios could distinguish subjects with HS from unaffected individuals ( P 0.05). Although the CHT and supplementary hematimetric indexes were useful to differentiate individuals with SH from healthy controls, they cannot distinguish from anemias of other etiology. CHT and MCHC, in addition to EOF, are recommended for diagnosing HS patients because of their low cost and efficiency.

  13. Effect of packing on changes in erythrocyte osmotic fragility and malondialdehyde concentration in donkeys administered with ascorbic acid

    Directory of Open Access Journals (Sweden)

    Folashade Olaifa

    2012-02-01

    Full Text Available Experiments were performed with the aim of investigating the effect of packing on erythrocyte osmotic fragility (EOF and malondialdehyde (MDA concentration in donkeys, and the effect of ascorbic acid (AA. Twelve apparently healthy donkeys raised under the traditional extensive system served as experimental subjects. Six donkeys administered orally with AA (200 mg/kg and subjected to packing were used as experimental animals, whilst six others not administered with AA served as controls. Blood samples were collected pre- and post-packing from all the donkeys for the determination of MDA and EOF. At 0.3% Sodium Chloride (NaCl concentration, the percentage haemolysis was 93.69% ± 2.21% in the control donkeys and the value was significantly (P < 0.05 higher than the value of 71.31% ± 8.33%, recorded in the experimental donkeys. The post-packing MDA concentration obtained in the control donkeys was 39.62 µmol ± 4.16 µmol, and was not significantly different (P > 0.05 from the value of 35.97 µmol ± 2.88 µmol recorded in the experimental donkeys. In conclusion, the increase in haemolysis obtained in the donkeys suggested that packing induced oxidative stress, which was ameliorated by AA administration.

  14. The Influence of the Osmotic Dehydration Process on Physicochemical Properties of Osmotic Solution.

    Science.gov (United States)

    Lech, Krzysztof; Michalska, Anna; Wojdyło, Aneta; Nowicka, Paulina; Figiel, Adam

    2017-12-16

    The osmotic dehydration (OD) process consists of the removal of water from a material during which the solids from the osmotic solution are transported to the material by osmosis. This process is commonly performed in sucrose and salt solutions. Taking into account that a relatively high consumption of those substances might have a negative effect on human health, attempts have been made to search for alternatives that can be used for osmotic dehydration. One of these is an application of chokeberry juice with proven beneficial properties to human health. This study aimed to evaluate the physicochemical properties of the OD solution (chokeberry juice concentrate) before and after the osmotic dehydration of carrot and zucchini. The total polyphenolics content, antioxidant capacity (ABTS, FRAP), dynamic viscosity, density, and water activity were examined in relation to the juice concentration used for the osmotic solution before and after the OD process. During the osmotic dehydration process, the concentration of the chokeberry juice decreased. Compounds with lower molecular weight and lower antioxidant capacity present in concentrated chokeberry juice had a stronger influence on the exchange of compounds during the OD process in carrot and zucchini. The water activity of the osmotic solution increased after the osmotic dehydration process. It was concluded that the osmotic solution after the OD process might be successfully re-used as a product with high quality for i.e. juice production.

  15. The rate of hypo-osmotic challenge influences regulatory volume decrease (RVD) and mechanical properties of articular chondrocytes.

    Science.gov (United States)

    Wang, Z; Irianto, J; Kazun, S; Wang, W; Knight, M M

    2015-02-01

    Osteoarthritis (OA) is associated with a gradual reduction in the interstitial osmotic pressure within articular cartilage. The aim of this study was to compare the effects of sudden and gradual hypo-osmotic challenge on chondrocyte morphology and biomechanics. Bovine articular chondrocytes were exposed to a reduction in extracellular osmolality from 327 to 153 mOsmol/kg applied either suddenly (osmotic stress, 66% of chondrocytes exhibited an increase in diameter followed by RVD, whilst 25% showed no RVD. By contrast, cells exposed to gradual hypo-osmotic stress exhibited reduced cell swelling without subsequent RVD. There was an increase in the equilibrium modulus for cells exposed to sudden hypo-osmotic stress. However, gradual hypo-osmotic challenge had no effect on cell mechanical properties. This cell stiffening response to sudden hypo-osmotic challenge was abolished when actin organization was disrupted with cytochalasin D or RVD inhibited with REV5901. Both sudden and gradual hypo-osmotic challenge reduced cortical F-actin distribution and caused chromatin decondensation. Sudden hypo-osmotic challenge increases chondrocyte mechanics by activation of RVD and interaction with the actin cytoskeleton. Moreover, the rate of hypo-osmotic challenge is shown to have a profound effect on chondrocyte morphology and biomechanics. This important phenomenon needs to be considered when studying the response of chondrocytes to pathological hypo-osmotic stress. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  16. Effect of laser light on the fragility and permeability of the red blood cell membrane

    International Nuclear Information System (INIS)

    El-Yassin, H. D.

    2005-01-01

    The resistance of red blood cells to hypotonic hemolysis is often characterized in terms of their osmotic fragility. The percentage of cells that hemolize when plotted as a function of different concentrations of NaCl forms fragility curve, which has a sigmoidal shape. In this study we show that the exposure of red blood cells to laser light converts the sigmoidal shape of the fragility curve to a hyperbolic one, which means that the old population of the red blood cells are the ones more affected by the light which cause their destruction. At the same time it seems that transport across the cell membrane is affected also. The biochemical and physiological implications of this finding are discussed. (author)

  17. Osmotic stress alters chromatin condensation and nucleocytoplasmic transport

    Energy Technology Data Exchange (ETDEWEB)

    Finan, John D.; Leddy, Holly A. [Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC (United States); Department of Biomedical Engineering, Duke University, Durham, NC (United States); Guilak, Farshid, E-mail: guilak@duke.edu [Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC (United States); Department of Biomedical Engineering, Duke University, Durham, NC (United States)

    2011-05-06

    Highlights: {yields} The rate of nucleocytoplasmic transport increases under hyper-osmotic stress. {yields} The mechanism is a change in nuclear geometry, not a change in permeability of the nuclear envelope. {yields} Intracytoplasmic but not intranuclear diffusion is sensitive to osmotic stress. {yields} Pores in the chromatin of the nucleus enlarge under hyper-osmotic stress. -- Abstract: Osmotic stress is a potent regulator of biological function in many cell types, but its mechanism of action is only partially understood. In this study, we examined whether changes in extracellular osmolality can alter chromatin condensation and the rate of nucleocytoplasmic transport, as potential mechanisms by which osmotic stress can act. Transport of 10 kDa dextran was measured both within and between the nucleus and the cytoplasm using two different photobleaching methods. A mathematical model was developed to describe fluorescence recovery via nucleocytoplasmic transport. As osmolality increased, the diffusion coefficient of dextran decreased in the cytoplasm, but not the nucleus. Hyper-osmotic stress decreased nuclear size and increased nuclear lacunarity, indicating that while the nucleus was getting smaller, the pores and channels interdigitating the chromatin had expanded. The rate of nucleocytoplasmic transport was increased under hyper-osmotic stress but was insensitive to hypo-osmotic stress, consistent with the nonlinear osmotic properties of the nucleus. The mechanism of this osmotic sensitivity appears to be a change in the size and geometry of the nucleus, resulting in a shorter effective diffusion distance for the nucleus. These results may explain physical mechanisms by which osmotic stress can influence intracellular signaling pathways that rely on nucleocytoplasmic transport.

  18. Flow cytometric determination of osmotic behaviour of animal erythrocytes toward their engineering for drug delivery

    Directory of Open Access Journals (Sweden)

    Kostić Ivana T.

    2015-01-01

    Full Text Available Despite the fact that the methods based on the osmotic properties of the cells are the most widely used for loading of drugs in human and animal erythrocytes, data related to the osmotic properties of erythrocytes derived from animal blood are scarce. This work was performed with an aim to investigate the possibility of use the flow cytometry as a tool for determination the osmotic behaviour of porcine and bovine erythrocytes, and thus facilitate the engineering of erythrocytes from animal blood to be drug carriers. The method of flow cytometry successfully provided the information about bovine and porcine erythrocyte osmotic fragility, and made the initial steps in assessment of erythrocyte shape in a large number of erythrocytes. Although this method is not able to confirm the swelling of pig erythrocytes, it indicated to the differences in pig erythrocytes that had basic hematological parameters inside and outside the reference values. In order to apply/use the porcine and bovine erythrocytes as drug carriers, the method of flow cytometry, confirming the presence of osmotically different fractions of red blood cells, indicated that various amounts of the encapsulated drug in porcine and bovine erythrocytes can be expected.

  19. Sea Water Acidification Affects Osmotic Swelling, Regulatory Volume Decrease and Discharge in Nematocytes of the Jellyfish Pelagia noctiluca

    Directory of Open Access Journals (Sweden)

    Rossana Morabito

    2013-12-01

    Full Text Available Background: Increased acidification/PCO2 of sea water is a threat to the environment and affects the homeostasis of marine animals. In this study, the effect of sea water pH changes on the osmotic phase (OP, regulatory volume decrease (RVD and discharge of the jellyfish Pelagia noctiluca (Cnidaria, Scyphozoa nematocytes, collected from the Strait of Messina (Italy, was assessed. Methods: Isolated nematocytes, suspended in artificial sea water (ASW with pH 7.65, 6.5 and 4.5, were exposed to hyposmotic ASW of the same pH values and their osmotic response and RVD measured optically in a special flow through chamber. Nematocyte discharge was analyzed in situ in ASW at all three pH values. Results: At normal pH (7.65, nematocytes subjected to hyposmotic shock first expanded osmotically and then regulated their cell volume within 15 min. Exposure to hyposmotic ASW pH 6.5 and 4.5 compromised the OP and reduced or totally abrogated the ensuing RVD, respectively. Acidic pH also significantly reduced the nematocyte discharge response. Conclusion: Data indicate that the homeostasis and function of Cnidarians may be altered by environmental changes such as sea water acidification, thereby validating their use as novel bioindicators for the quality of the marine environment.

  20. Sea water acidification affects osmotic swelling, regulatory volume decrease and discharge in nematocytes of the jellyfish Pelagia noctiluca.

    Science.gov (United States)

    Morabito, Rossana; Marino, Angela; Lauf, Peter K; Adragna, Norma C; La Spada, Giuseppa

    2013-01-01

    Increased acidification/PCO2 of sea water is a threat to the environment and affects the homeostasis of marine animals. In this study, the effect of sea water pH changes on the osmotic phase (OP), regulatory volume decrease (RVD) and discharge of the jellyfish Pelagia noctiluca (Cnidaria, Scyphozoa) nematocytes, collected from the Strait of Messina (Italy), was assessed. Isolated nematocytes, suspended in artificial sea water (ASW) with pH 7.65, 6.5 and 4.5, were exposed to hyposmotic ASW of the same pH values and their osmotic response and RVD measured optically in a special flow through chamber. Nematocyte discharge was analyzed in situ in ASW at all three pH values. At normal pH (7.65), nematocytes subjected to hyposmotic shock first expanded osmotically and then regulated their cell volume within 15 min. Exposure to hyposmotic ASW pH 6.5 and 4.5 compromised the OP and reduced or totally abrogated the ensuing RVD, respectively. Acidic pH also significantly reduced the nematocyte discharge response. Data indicate that the homeostasis and function of Cnidarians may be altered by environmental changes such as sea water acidification, thereby validating their use as novel bioindicators for the quality of the marine environment. © 2014 S. Karger AG, Basel.

  1. Studies on osmotic concentration of radioactive effluents

    International Nuclear Information System (INIS)

    Thomas, K.C.; Ramachandhran, V.; Misra, B.M.

    1986-01-01

    The potential of direct osmosis for concentrating radioactive effluents is examined on the laboratory scale. Studies were carried out using asymmetric cellulose acetate membranes of a range of porosities under varying salinity gradients. A suitable bench scale osmotic concentrator employing tubular membrane systems has been fabricated and tested. An attempt to understand the mechanism of water permeation under osmotic and hydrostatic gradients has been made based on the irreversible thermodynamic approach. The solute separation of sodium chloride and radionuclides under osmosis is in the range of 85 to 95% for various osmotic sink solutions. The osmotic water flux is observed to be lower than the hydraulic water flux under reverse osmosis conditions. While the solute separation increases with an increase in annealing temperature, water flux decreases for both osmosis and reverse osmosis systems for various feed salinities. The effect of concentration polarization is analysed, and the effect of feed and osmotic sink velocity on the performance of the osmotic concentrator has also been studied. (orig.)

  2. The dependence of molecular transmembrane electrotransfer efficiency on medium conductivity and osmotic pressure

    OpenAIRE

    Jakutavičiūtė, Milda; Ruzgys, Paulius; Šatkauskas, Saulius

    2014-01-01

    The electrotransfer efficiency was evaluated for different external medium conductivities, osmotic pressures and electric pulse voltages. It was found that increase in conductivity or decrease in electric pulse strength decreases electrotransfer efficiency. Decrease in osmotic pressure tends to decrease electrotransfer efficiency.

  3. Plasma osmotic changes during major abdominal surgery.

    Science.gov (United States)

    Malone, R A; McLeavey, C A; Arens, J F

    1977-12-01

    Fluid balance across the capillary membrane is maintained normally by a balance of hydrostatic and colloid osmotic pressures (COP). In 12 patients having major intra-abdominal procedures, the COP was followed during the operative and immediate postoperative periods. The patients' intraoperative fluid management consisted of replacing shed blood with blood and following Shires' concept of crystalloid replacement. Significant decreases in COP to approximately two thirds of the initial value occurred in patients having intra-abdominal procedures versus only a 10 percent decrease in those having peripheral procedures (greater than .001). As a result of this decrease in COP, the balance between hydrostatic and colloid osmotic pressures is lost and risk of pulmonary intersitial edema is increased.

  4. Mechanism of actuation in conducting polymers: Osmotic expansion

    DEFF Research Database (Denmark)

    Bay, Lasse; Jacobsen, Torben; West, Keld

    2001-01-01

    Conducting polymers expand or contract when their redox state is changed. This expansion/contraction effect can be separated in an intrinsic part because of changes of the polymer backbone on reduction/oxidation and a part depending on the surrounding electrolyte phase, because of osmotic expansion...... is compared with measurements on PPy(DBS) films. The experiments show that the expansion decreases as the electrolyte concentration is increased. This means that a considerable part of the total expansion is due to the osmotic effect. The osmotic effect should be taken into account when interpreting...

  5. A micropuncture study of proximal tubular transport of lithium during osmotic diuresis

    DEFF Research Database (Denmark)

    Leyssac, P P; Holstein-Rathlou, N H; Skøtt, P

    1990-01-01

    Lithium and sodium are normally reabsorbed in parallel with water by the renal proximal tubule whereby their tubular fluid-to-plasma concentration ratios (TF/P) remain close to unity throughout the proximal convoluted segment. During osmotic diuresis, the late proximal (TF/P)Na is known to decrease....... The present experiments were undertaken to study whether the late proximal TF/P for Li decreases like that of Na during osmotic diuresis. Data were obtained in a control period (C) and in two successive periods during mannitol diuresis (P1, P2). Glomerular filtration rate decreased gradually during osmotic...

  6. The Role of Superoxide Dismutase in Inducing of Wheat Seedlings Tolerance to Osmotic Shock

    Directory of Open Access Journals (Sweden)

    Oboznyi A.I.

    2013-08-01

    Full Text Available Influence of short-term hardening osmotic exposure (immersion in 1 M sucrose solution with subsequent transferring to distilled water for 20 min on the hydrogen peroxide generation and superoxide dismutase activity in wheat (Triticum aestivum L., cv. Elegiya seedlings and their tolerance to osmotic shock were investigated. During the initial 30 min after osmotic exposure, the increasing of hydrogen peroxide amount in roots and shoots (to a lesser extent was observed, but the resistance of the seedlings and superoxide dismutase (SOD activity decreased. Sometime later the decrease in hydrogen peroxide amount and the increase of seedlings tolerance to osmotic shock took place. SOD activity increased in 10 min after hardening osmotic exposure. Transient accumulation of hydrogen peroxide induced in this way was suppressed by the treatment of seedlings with sodium diethyldithiocarbamate (DDC, SOD inhibitor. DDC and hydrogen peroxide scavenger dimethylthiourea decreased positive hardening effect of osmotic exposure on the development of seedlings tolerance. It was concluded that SOD providing the generation of signal hydrogen peroxide pool took part in the induction of seedlings tolerance to osmotic shock development caused by preliminary hardening effect.

  7. Osmotic dehydration of fruit and berry raw materials in the food industry

    Directory of Open Access Journals (Sweden)

    N. A. Gribova

    2017-01-01

    Full Text Available Osmotic dehydration has recently received more attention as an effective method of preserving fruits and berries. Osmosis is a simple process that facilitates the processing of fruits and berries in order to preserve the original characteristics, namely nutritional value and organoleptic properties: color, aroma and texture. Osmotic dehydration has found wide application in the preservation of food products, as the activity of water in fruits and berries decreases, in some of them up to 90% of water is contained. The process of osmotic dehydration with the help of various agents is less energy-intensive than the process of drying or freezing, since it can be processed at ambient temperature. Osmotic dehydration has potential advantages in preserving the quality of food and in maintaining healthy food for the food industry. Treatment includes dehydration of fruits and berries by an osmotic agent followed by dehydration in dry or frozen apparatus where the moisture content decreases and the product becomes more stable. This process is a partial dewatering process to provide improved product quality compared to conventional drying processes or freezing. The purpose of studying osmotic dehydration is to identify the advantages and disadvantages in the treatment of osmotic agents. Various aspects of osmotic dehydration technology are considered, namely the solutions used, the characteristics of solutions, the effect of variable processes and the qualitative characteristics of osmo-dehydrated products. Factors of osmotic dehydration that depend on the osmotic agent, concentration of solute, temperature, time, size, shape and compactness of the material, mixing and the ratio of the solution to the samples.

  8. Effect of plasma colloid osmotic pressure on intraocular pressure during haemodialysis

    OpenAIRE

    Tokuyama, T.; Ikeda, T.; Sato, K.

    1998-01-01

    BACKGROUND—In a previous case report, it was shown that an increase in plasma colloid osmotic pressure induced by the removal of fluid during haemodialysis was instrumental in decreasing intraocular pressure. The relation between changes in intraocular pressure, plasma osmolarity, plasma colloid osmotic pressure, and body weight before and after haemodialysis is evaluated.
METHODS—Intraocular pressure, plasma osmolarity, plasma colloid osmotic pressure, and body weight were evaluated before a...

  9. Saltstone Osmotic Pressure

    International Nuclear Information System (INIS)

    Nichols, Ralph L.; Dixon, Kenneth L.

    2013-01-01

    Recent research into the moisture retention properties of saltstone suggest that osmotic pressure may play a potentially significant role in contaminant transport (Dixon et al., 2009 and Dixon, 2011). The Savannah River Remediation Closure and Disposal Assessments Group requested the Savannah River National Laboratory (SRNL) to conduct a literature search on osmotic potential as it relates to contaminant transport and to develop a conceptual model of saltstone that incorporates osmotic potential. This report presents the findings of the literature review and presents a conceptual model for saltstone that incorporates osmotic potential. The task was requested through Task Technical Request HLW-SSF-TTR-2013-0004. Simulated saltstone typically has very low permeability (Dixon et al. 2008) and pore water that contains a large concentration of dissolved salts (Flach and Smith 2013). Pore water in simulated saltstone has a high salt concentration relative to pore water in concrete and groundwater. This contrast in salt concentration can generate high osmotic pressures if simulated saltstone has the properties of a semipermeable membrane. Estimates of osmotic pressure using results from the analysis of pore water collected from simulated saltstone show that an osmotic pressure up to 2790 psig could be generated within the saltstone. Most semi-permeable materials are non-ideal and have an osmotic efficiency 3 , KNO 3 , Na 3 PO 4 x12H 2 O, and K 3 PO 4 when exposed to a dilute solution. Typically hydraulic head is considered the only driving force for groundwater in groundwater models. If a low permeability material containing a concentrated salt solution is present in the hydrogeologic sequence large osmotic pressures may develop and lead to misinterpretation of groundwater flow and solute transport. The osmotic pressure in the semi-permeable material can significantly impact groundwater flow in the vicinity of the semi-permeable material. One possible outcome is that

  10. Drying and osmotic conditioning in Hancornia speciosa Gomes seeds

    Directory of Open Access Journals (Sweden)

    Tathiana Elisa Masetto

    Full Text Available Hancornia speciosa is a native tree species of the Brazilian Cerrado whose seeds are desiccation sensitive. In this study, we aimed to evaluate drying and osmotic conditioning in H. speciosa seeds. We used fresh seeds with 48% moisture content, which were slowly dried until they attained contents of 20%, 15%, 10% and 5%. To evaluate osmotic conditioning, the seeds were imbibed in 12 mL osmotic solutions at 0.0; -0.2; -0.4 and -0.6 MPa for two days. After that, they were dehydrated until their original moisture content. The experiments were carried out in a completely randomized design with four repetitions with 50 seeds each. Reduction in moisture content from 20% to 5% decreased the physiological potential of seeds. H. speciosa seeds do not require osmotic priming with PEG solutions, because imbibition of seeds in osmotic solutions of up to -0.6 MPa results in reduction of germination rate and seedling length.

  11. Salt Effect on Osmotic Pressure of Polyelectrolyte Solutions: Simulation Study

    Directory of Open Access Journals (Sweden)

    Jan-Michael Y. Carrillo

    2014-07-01

    Full Text Available Abstract: We present results of the hybrid Monte Carlo/molecular dynamics simulations of the osmotic pressure of salt solutions of polyelectrolytes. In our simulations, we used a coarse-grained representation of polyelectrolyte chains, counterions and salt ions. During simulation runs, we alternate Monte Carlo and molecular dynamics simulation steps. Monte Carlo steps were used to perform small ion exchange between simulation box containing salt ions (salt reservoir and simulation box with polyelectrolyte chains, counterions and salt ions (polyelectrolyte solution. This allowed us to model Donnan equilibrium and partitioning of salt and counterions across membrane impermeable to polyelectrolyte chains. Our simulations have shown that the main contribution to the system osmotic pressure is due to salt ions and osmotically active counterions. The fraction of the condensed (osmotically inactive counterions first increases with decreases in the solution ionic strength then it saturates. The reduced value of the system osmotic coefficient is a universal function of the ratio of the concentration of osmotically active counterions and salt concentration in salt reservoir. Simulation results are in a very good agreement with osmotic pressure measurements in sodium polystyrene sulfonate, DNA, polyacrylic acid, sodium polyanetholesulfonic acid, polyvinylbenzoic acid, and polydiallyldimethylammonium chloride solutions.

  12. Development of hyper osmotic resistant CHO host cells for enhanced antibody production.

    Science.gov (United States)

    Kamachi, Yasuharu; Omasa, Takeshi

    2018-04-01

    Cell culture platform processes are generally employed to shorten the duration of new product development. A fed-batch process with continuous feeding is a conventional platform process for monoclonal antibody production using Chinese hamster ovary (CHO) cells. To establish a simplified platform process, the feeding method can be changed from continuous feed to bolus feed. However, this change induces a rapid increase of osmolality by the bolus addition of nutrients. The increased osmolality suppresses cell culture growth, and the final product concentration is decreased. In this study, osmotic resistant CHO host cells were developed to attain a high product concentration. To establish hyper osmotic resistant CHO host cells, CHO-S host cells were passaged long-term in a hyper osmotic basal medium. There were marked differences in cell growth of the original and established host cells under iso- (328 mOsm/kg) or hyper-osmolality (over 450 mOsm/kg) conditions. Cell growth of the original CHO host cells was markedly decreased by the induction of osmotic stress, whereas cell growth of the hyper osmotic resistant CHO host cells was not affected. The maximum viable cell concentration of hyper osmotic resistant CHO host cells was 132% of CHO-S host cells after the induction of osmotic stress. Moreover, the hyper osmotic resistant characteristic of established CHO host cells was maintained even after seven passages in iso-osmolality basal medium. The use of hyper osmotic resistance CHO host cells to create a monoclonal antibody production cell line might be a new approach to increase final antibody concentrations with a fed-batch process. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  13. Saltstone Osmotic Pressure

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, Ralph L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Dixon, Kenneth L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRN

    2013-09-23

    Recent research into the moisture retention properties of saltstone suggest that osmotic pressure may play a potentially significant role in contaminant transport (Dixon et al., 2009 and Dixon, 2011). The Savannah River Remediation Closure and Disposal Assessments Group requested the Savannah River National Laboratory (SRNL) to conduct a literature search on osmotic potential as it relates to contaminant transport and to develop a conceptual model of saltstone that incorporates osmotic potential. This report presents the findings of the literature review and presents a conceptual model for saltstone that incorporates osmotic potential. The task was requested through Task Technical Request HLW-SSF-TTR- 2013-0004.

  14. Study of Red Cell Fragility in Different Stages of Chronic Kidney Disease in Relation to Parathyroid Hormone.

    Science.gov (United States)

    Panda, Suchismita; Mishra, Anuva; Jena, Manoranjan; Rout, Sashi Bhusan; Mohapatra, Srikrushna

    2017-08-01

    Anaemia is one of the common complications associated with Chronic Kidney Disease (CKD) responsible for the increase in the morbidity and mortality in such patients. Several factors have been attributed to cause renal anaemia, amongst which hyperparathyroidism is one of the less recognised reasons. Most studies have been conducted in this regard in CKD patients undergoing haemodialysis. The level of PTH in early stages of chronic kidney disease has not been much studied. The excess amount of Parathyroid Hormone (PTH) secondary to CKD has been suggested to be a causative factor for anaemia. To evaluate the serum PTH level in CKD patients before haemodialysis and to study the association of the haemoglobin status with the parathyroid hormone. Forty CKD patients above 18 years of age before haemodialysis and 25 age and sex matched healthy controls were included in the study. Routine biochemical and haematological parameters such as Routine Blood Sugar (RBS), urea, creatinine, Na + , K + , Ca 2+ , PTH and Hb% were perfomed. Red cell osmotic fragility was measured by serial dilutions of whole blood with varying concentrations of sodium chloride ranging from 0.1% to 0.9%. The study revealed a significant fall in Hb%, along with a rise in Median Osmotic Fragility (MOF) and PTH in the CKD patients when compared to the control group. Linear regression of PTH with Hb% revealed significant negative association between both the parameters with a R 2 value of 0.677. Multilinear regression analysis of MOF and other independent variables such as Hb%, Na + , K + , Ca 2+ , urea, PTH and creatinine highlighted the variance of MOF by 72%, maximal variance contributed by PTH. Receiver Operating Curve (ROC) analysis revealed an area under the curve of 0.980 with a sensitivity of 100% and specificity of 87% in detecting osmotic fragility at a cut off value of PTH ≥100 pg/ml. The underlying cause of anaemia should be identified early in the CKD patients before haemodialysis. Secondary

  15. Influence of electromagnetic radiation produced by mobile phone on some biophysical blood properties in rats.

    Science.gov (United States)

    El-Bediwi, Abu Bakr; Saad, Mohamed; El-kott, Attall F; Eid, Eman

    2013-04-01

    Effects of electromagnetic radiation produced by mobile phone on blood viscosity, plasma viscosity, hemolysis, Osmotic fragility, and blood components of rats have been investigated. Experimental results show that there are significant change on blood components and its viscosity which affects on a blood circulation due to many body problems. Red blood cells, White blood cells, and Platelets are broken after exposure to electromagnetic radiation produced by mobile phone. Also blood viscosity and plasma viscosity values are increased but Osmotic fragility value decreased after exposure to electromagnetic radiation produced by mobile phone.

  16. Influence of osmotic pressure changes on the opening of existing cracks in 2 intervertebral disc models

    NARCIS (Netherlands)

    Wognum, Silvia; Huyghe, Jacques M.; Baaijens, Frank P. T.

    2006-01-01

    An experimental hydrogel model and a numerical mixture model were used to investigate why the disc herniates while osmotic pressure is decreasing. To investigate the influence of decreasing osmotic pressure on the opening of cracks in the disc. In the degeneration process, the disc changes structure

  17. Neutral lipid production in Dunaliella salina during osmotic stress and adaptation

    DEFF Research Database (Denmark)

    Yao, Shuo; Lu, Jingquan; Sárossy, Zsuzsa

    2016-01-01

    The salt-tolerant green microalga Dunaliella salina can survive both hyper- and hypo-osmotic shock. Upon osmotic shock, the cells transiently and rapidly decreased or increased in size within minutes and slowly over hours acquired their original cell size and volume. Cell size distribution differs...... significantly in the cultures grown in the salinity range from 1.5 to 15 % NaCl. By using Nile Red fluorescence to detect neutral lipids, it became clear that only hyper-osmotic shock on cells induced transient neutral lipid appearance in D. salina, while those transferred from 9 to 15 % NaCl stimulated...

  18. A novel zinc-finger-like gene from Tamarix hispida is involved in salt and osmotic tolerance.

    Science.gov (United States)

    An, Yan; Wang, Yucheng; Lou, Lingling; Zheng, Tangchun; Qu, Guan-Zheng

    2011-11-01

    In the present study, a zinc-finger-like cDNA (ThZFL) was cloned from the Tamarix hispida. Northern blot analysis showed that the expression of ThZFL can be induced by salt, osmotic stress and ABA treatment. Overexpression of the ThZFL confers salt and osmotic stress tolerance in both yeast Saccharomyces cerevisiae and tobacco. Furthermore, MDA levels in ThZFL transformed tobacco were significantly decreased compared with control plants under salt and osmotic stress, suggesting ThZFL may confer stress tolerance by decreasing membrane lipid peroxidation. Subcellular localization analysis showed the ThZFL protein is localized in the cell wall. Our results indicated the ThZFL gene is an excellent candidate for genetic engineering to improve salt and osmotic tolerance in agricultural plants.

  19. Fragile X syndrome and fragile X-associated tremor ataxia syndrome.

    Science.gov (United States)

    Hall, Deborah A; Berry-Kravis, Elizabeth

    2018-01-01

    Fragile X-associated disorders encompass several conditions, which are caused by expansion mutations in the fragile X mental retardation 1 (FMR1) gene. Fragile X syndrome is the most common inherited etiology of intellectual disability and results from a full mutation or >200 CGG repeats in FMR1. It is associated with developmental delay, autism spectrum disorder, and seizures. Fragile X-associated tremor/ataxia syndrome is a progressive neurodegenerative disease that occurs in premutation carriers of 55-200 CGG repeats in FMR1 and is characterized by kinetic tremor, gait ataxia, parkinsonism, executive dysfunction, and neuropathy. Fragile X-associated primary ovarian insufficiency also occurs in premutation carrier women and manifests with infertility and early menopause. The diseases constituting fragile X-associated disorders differ mechanistically, due to the distinct molecular properties of premutation versus full mutations. Fragile X syndrome occurs when there is a lack of fragile X mental retardation protein (FMRP) due to FMR1 methylation and silencing. In fragile X-associated tremor ataxia syndrome, a toxic gain of function is postulated with the production of excess CGG repeat-containing FMR1 mRNA, abnormal translation of the repeat sequence leading to production of polyglycine, polyalanine, and other polypeptides and to outright deficits in translation leading to reduced FMRP at larger premutation sizes. The changes in underlying brain chemistry due to FMR1 mutations have led to therapeutic studies in these disorders, with some progress being made in fragile X syndrome. This paper also summarizes indications for testing, genetic counseling issues, and what the future holds for these disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Role of Osmotic Adjustment in Plant Productivity

    Energy Technology Data Exchange (ETDEWEB)

    Gebre, G.M.

    2001-01-11

    Successful implementation of short rotation woody crops requires that the selected species and clones be productive, drought tolerant, and pest resistant. Since water is one of the major limiting factors in poplar (Populus sp.) growth, there is little debate for the need of drought tolerant clones, except on the wettest of sites (e.g., lower Columbia River delta). Whether drought tolerance is compatible with productivity remains a debatable issue. Among the many mechanisms of drought tolerance, dehydration postponement involves the maintenance of high leaf water potential due to, for example, an adequate root system. This trait is compatible with productivity, but requires available soil moisture. When the plant leaf water potential and soil water content decline, the plant must be able to survive drought through dehydration tolerance mechanisms, such as low osmotic potential or osmotic adjustment. Osmotic adjustment and low osmotic potential are considered compatible with growth and yield because they aid in the maintenance of leaf turgor. However, it has been shown that turgor alone does not regulate cell expansion or stomatal conductance and, therefore, the role of osmotic adjustment is debated. Despite this finding, osmotic adjustment has been correlated with grain yield in agronomic crop species, and gene markers responsible for osmotic adjustment are being investigated to improve drought tolerance in productive progenies. Although osmotic adjustment and low osmotic potentials have been investigated in several forest tree species, few studies have investigated the relationship between osmotic adjustment and growth. Most of these studies have been limited to greenhouse or container-grown plants. Osmotic adjustment and rapid growth have been specifically associated in Populus and black spruce (Picea mariuna (Mill.) B.S.P.) progenies. We tested whether these relationships held under field conditions using several poplar clones. In a study of two hybrid poplar

  1. Biochemical changes and manifestations of envenomation produced by Odonthobuthus doriae venom in rabbits

    Directory of Open Access Journals (Sweden)

    A. Z. Mirakabadi

    2006-01-01

    Full Text Available Many toxins from scorpion venoms cause neurotransmitters release by activating the autonomic system. The aim of the present work was to determine osmotic fragility of red blood cells (RBCs and serum biochemical changes produced by the venom of Odonthobuthus doriae (O. doriae, a dangerous species of scorpion in Iran. For this study we selected 2 groups, each one containing 10 New Zealand white rabbits weighing 2 ± 0.2 kg. In vivo and in vitro osmotic fragilities as well as packed cell volume (PCV were determined. Serum was separated and used for determination of glucose, blood urea nitrogen (BUN, creatinine, uric acid (UA, triglycerides, cholesterol, aspartate aminotransferase (AST, EC 2.6.1.1, and alanine aminotransferase (ALT, EC 2.6.1.2. Results indicate that Odonthobuthus doriae venom (0.5 mg/kg, IV causes a significant increase (p<0.05 of serum glucose, UA, PCV, ALT, and AST. Increase was also observed in BUN, but it was not statistically significant. On the other hand a significant decrease (p<0.05 was observed in triglycerides and cholesterol levels. Increased in vivo osmotic fragility of RBCs was significant too, but in vitro osmotic fragility did not show a significant change. These results support the hypothesis that the biochemical variation caused by scorpion venom can be due to an autonomic storm and release of catecholamines.

  2. Whole body gamma radiation effects on rheological behaviour (deformability) of rat erythrocytes

    International Nuclear Information System (INIS)

    Soliman, M.S.

    2004-01-01

    This study was designed to determine the effect of whole body gamma irradiation on the rheological behaviour of rat erythrocytes (deformability). Animals were divided into 4 irradiated groups and 4 control groups according to their sacrificing time intervals (1 st, 3 rd, 5 th and 7 th days) post-irradiation with dose (6 Gy). In all animals and at the previous time intervals, red blood cell (RBC) membrane proteins electrophoretic pattern, RBC membrane lipids levels (cholesterol and phospholipids), RBC electrolytes levels (sodium, potassium and calcium), corpuscular osmotic fragility and RBC morphological by scanning electron microscopy were determined. Highly significant increase in membrane cholesterol, RBC sodium, calcium and corpuscular osmotic fragility accompanied by highly significant decrease in membrane phospholipids, RBC potassium and RBC deformability were found. No changes in membrane proteins electrophoretic patterns were detected. Morphologically, there were increase in the incidences of echinocytes and spherocytes development, which were time dependent. According to the previous results, irradiation promotes alterations in RBC shape (echinocytosis), membrane skeletal dysfunction, membrane lipid peroxidation, increase in membrane cholesterol/phospholipid content, changes in membrane electrolyte permeability and decrease then increase in osmotic fragility. These alterations in turn led to decrease in cellular deformability as a result of increased membrane rigidity and also due to cells dehydration caused by excess leakage of potassium ions from the RBCs

  3. Equipment fragility testing

    International Nuclear Information System (INIS)

    Holman, G.S.; Chou, C.K.; Cummings, G.E.

    1985-01-01

    Current probabilistic risk assessment (PRA) methods for nuclear power plants utilize component fragilities which are for the most part based on a limited data base and engineering judgement. The seismic design of components is based on code limits and NRC requirements that do not reflect the actual capacity of a component to resist failure. In order to improve the present component fragility data base and establish component seismic design margins, the NRC has commissioned a projected three-year program to compile existing fragilities data and at the same time independently perform fragilities tests on selected mechanical and electrical components. This paper presents the planning and technical approach being taken by LLNL in the NRC Component Fragility Program

  4. Influence of high energy electron irradiation and gamma irradiation on the osmotic resistance of human erythrocyte membranes

    International Nuclear Information System (INIS)

    Catana, D.; Hategan, Alina; Moraru, Rodica; Popescu, Alina; Morariu, V. V.

    1998-01-01

    The effects of 5 MeV electrons and of gamma irradiation at 0 deg. C on the osmotic fragility of human erythrocyte membranes are presented. Both electron and gamma radiation in the range 0-400 Gy induced no hemolysis indicating that the membrane modifications due to radiation interaction do not reach a critical point as to cause swelling of the cells and subsequent lysis. The osmotic stress experiments performed after irradiation showed that the gamma irradiated erythrocytes exhibited an almost similar sigmoidal behavior for all irradiation doses, whereas the electron irradiated samples showed a much larger increase in hemolysis degree and, in the case of a given electron dose (100 Gy), the hemolysis was found much smaller than for the control sample (a similar behavior of the erythrocytes was found in the case of microwave irradiation at temperatures under 0 deg. C). Our experimental data suggest that electron radiation and gamma radiation have different impacts on the erythrocyte membrane fluidity, involving, probably, the different rate of energy deposition in the samples and the direct interaction of electrons with the erythrocyte membranes. (authors)

  5. Hydrothermal Carbonization of Spent Osmotic Solution (SOS Generated from Osmotic Dehydration of Blueberries

    Directory of Open Access Journals (Sweden)

    Kaushlendra Singh

    2014-09-01

    Full Text Available Hydrothermal carbonization of spent osmotic solution (SOS, a waste generated from osmotic dehydration of fruits, has the potential of transformation into hydrochars, a value-added product, while reducing cost and overall greenhouse gas emissions associated with waste disposal. Osmotic solution (OS and spent osmotic solution (SOS generated from the osmotic dehydration of blueberries were compared for their thermo-chemical decomposition behavior and hydrothermal carbonization. OS and SOS samples were characterized for total solids, elemental composition, and thermo-gravimetric analysis (TGA. In addition, hydrothermal carbonization was performed at 250 °C and for 30 min to produce hydrochars. The hydrochars were characterized for elemental composition, Brunauer-Emmett-Teller (BET surface area, particle shape and surface morphology. TGA results show that the SOS sample loses more weight in the lower temperature range than the OS sample. Both samples produced, approximately, 40%–42% (wet-feed basis hydrochar during hydrothermal carbonization but with different properties. The OS sample produced hydrochar, which had spherical particles of 1.79 ± 1.30 μm diameter with a very smooth surface. In contrast, the SOS sample produced hydrochar with no definite particle shape but with a raspberry-like surface.

  6. Erythrocyte osmotic fragility and general health status of adolescent Sprague Dawley rats supplemented with Hibiscus sabdariffa aqueous calyx extracts as neonates followed by a high-fructose diet post-weaning.

    Science.gov (United States)

    Ibrahim, K G; Lembede, B W; Chivandi, E; Erlwanger, K

    2018-02-01

    High-fructose diets (HFD) can cause oxidative damage to tissues including erythrocyte cell membranes. Hibiscus sabdariffa (HS) has protective antioxidant properties. Rats were used to investigate whether the consumption of HS by neonates would result in long-term effects on their erythrocyte osmotic fragility (EOF) and general health when later fed a high-fructose diet post-weaning through adolescence. Eighty of four-day-old Sprague Dawley rat pups were divided randomly into three treatment groups. The controls (n = 27) received distilled water at 10 ml/kg b. w, while the other groups received either 50 mg/kg (n = 28) or 500 mg/kg (n = 25) of an HS aqueous calyx extract orally till post-natal day 14. The rats in each group were weaned and divided into two subgroups; one continued on normal rat chow, and the other received fructose (20% w/v) in their drinking water for 30 days. Blood was collected in heparinised tubes and added to serially diluted (0.0-0.85%) phosphate-buffered saline to determine the EOF. Clinical markers of health status were determined with an automated chemical analyser. HS extracts did not programme metabolism in the growing rats to alter their general health and EOF in response to the HFD. © 2017 Blackwell Verlag GmbH.

  7. Osmotic dehydration of fruit and berry raw materials in the food industry

    OpenAIRE

    N. A. Gribova; L. G. Eliseeva

    2017-01-01

    Osmotic dehydration has recently received more attention as an effective method of preserving fruits and berries. Osmosis is a simple process that facilitates the processing of fruits and berries in order to preserve the original characteristics, namely nutritional value and organoleptic properties: color, aroma and texture. Osmotic dehydration has found wide application in the preservation of food products, as the activity of water in fruits and berries decreases, in some of them up to 90% o...

  8. Mechanisms of diabetes mellitus-induced bone fragility

    DEFF Research Database (Denmark)

    Napoli, Nicola; Chandran, Manju; Pierroz, Dominique D

    2017-01-01

    The risk of fragility fractures is increased in patients with either type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM). Although BMD is decreased in T1DM, BMD in T2DM is often normal or even slightly elevated compared with an age-matched control population. However, in both T1DM...... and T2DM, bone turnover is decreased and the bone material properties and microstructure of bone are altered; the latter particularly so when microvascular complications are present. The pathophysiological mechanisms underlying bone fragility in diabetes mellitus are complex, and include hyperglycaemia......-induced hypoglycaemia, certain antidiabetic medications with a direct effect on bone and mineral metabolism (such as thiazolidinediones), as well as an increased propensity for falls, all contribute to the increased fracture risk in patients with diabetes mellitus....

  9. The plant cuticle is required for osmotic stress regulation of abscisic acid biosynthesis and osmotic stress tolerance in Arabidopsis

    KAUST Repository

    Wang, Zhenyu

    2011-05-01

    Osmotic stress activates the biosynthesis of abscisic acid (ABA). One major step in ABA biosynthesis is the carotenoid cleavage catalyzed by a 9-cis epoxycarotenoid dioxygenase (NCED). To understand the mechanism for osmotic stress activation of ABA biosynthesis, we screened for Arabidopsis thaliana mutants that failed to induce the NCED3 genee xpression in response to osmotic stress treatments. The ced1 (for 9-cis epoxycarotenoid dioxy genase defective 1) mutant isolated in this study showed markedly reduced expression of NCED3 in response to osmotic stress (polyethylene glycol)treatments compared with the wild type. Other ABA biosynthesis genes are also greatly reduced in ced1 under osmotic stress. ced1 mutant plants are very sensitive to even mild osmotic stress. Map-based cloning revealed unexpectedly thatCED1 encodes a putative a/b hydrolase domain-containing protein and is allelic to the BODYGUARD gene that was recently shown to be essential for cuticle biogenesis. Further studies discovered that other cut in biosynthesis mutants are also impaired in osmotic stress induction of ABA biosynthesis genes and are sensitive to osmotic stress. Our work demonstrates that the cuticle functions not merely as a physical barrier to minimize water loss but also mediates osmotic stress signaling and tolerance by regulating ABA biosynthesis and signaling. © 2011 American Society of Plant Biologists. All rights reserved.

  10. Osmotic water transport in aquaporins

    DEFF Research Database (Denmark)

    Zeuthen, Thomas; Alsterfjord, Magnus; Beitz, Eric

    2013-01-01

    Abstract  We test a novel, stochastic model of osmotic water transport in aquaporins. A solute molecule present at the pore mouth can either be reflected or permeate the pore. We assume that only reflected solute molecules induce osmotic transport of water through the pore, while permeating solute...... molecules give rise to no water transport. Accordingly, the rate of water transport is proportional to the reflection coefficient σ, while the solute permeability, P(S), is proportional to 1 - σ. The model was tested in aquaporins heterologously expressed in Xenopus oocytes. A variety of aquaporin channel...... sizes and geometries were obtained with the two aquaporins AQP1 and AQP9 and mutant versions of these. Osmotic water transport was generated by adding 20 mM of a range of different-sized osmolytes to the outer solution. The osmotic water permeability and the reflection coefficient were measured...

  11. Osmotic stress on nitrification in an airlift bioreactor

    International Nuclear Information System (INIS)

    Jin Rencun; Zheng Ping; Mahmood, Qaisar; Hu Baolan

    2007-01-01

    The effect of osmotic pressure on nitrification was studied in a lab-scale internal-loop airlift-nitrifying reactor. The reactor slowly adapted to the escalating osmotic pressure during 270 days operation. The conditions were reversed to the initial stage upon full inhibition of the process. Keeping influent ammonium concentration constant at 420 mg N L -1 and hydraulic retention time at 20.7 h, with gradual increase in osmotic pressure from 4.3 to 18.8 x 10 5 Pa by adding sodium sulphate, the ammonium removal efficiencies of the nitrifying bioreactor were maintained at 93-100%. Further increase in osmotic pressure up to 19.2 x 10 5 Pa resulted in drop of the ammonium conversion to 69.2%. The osmotic pressure caused abrupt inhibition of nitrification without any alarm and the critical osmotic pressure value causing inhibition remained between 18.8 and 19.2 x 10 5 Pa. Nitrite oxidizers were found more sensitive to osmotic stress as compared with ammonia oxidizers, leading to nitrite accumulation up to 61.7% in the reactor. The performance of bioreactor recovered gradually upon lowering the osmotic pressure. Scanning and transmission electron microscopy indicated that osmotic stress resulted in simplification of the nitrifying bacterial populations in the activated sludge as the cellular size reduced; the inner membrane became thinner and some unknown inclusions appeared within the cells. The microbial morphology and cellular structure restored upon relieving the osmotic pressure. Addition of potassium relieved the effect of osmotic pressure upon nitrification. Results demonstrate that the nitrifying reactor possesses the potential to treat ammonium-rich brines after acclimatization

  12. An analysis of the effects of osmotic backwashing on the seawater reverse osmosis process.

    Science.gov (United States)

    Park, JunYoung; Jeong, WooWon; Nam, JongWoo; Kim, JaeHun; Kim, JiHoon; Chon, Kangmin; Lee, Euijong; Kim, HyungSoo; Jang, Am

    2014-01-01

    Fouling control is an important consideration in the design and operation of membrane-based water treatment processes. It has been generally known that chemical cleaning is still the most common method to remove foultants and maintain the performance of reverse osmosis (RO) desalination. Regardless of the chemical membrane cleaning methods applied effectively, however, frequent chemical cleaning can shorten the membrane life. In addition, it also increases operating and maintenance costs due to the waste chemical disposal. As an alternative, osmotic backwashing can be applied to RO membranes by diluting the concentration polarization (CP) layer. In this study, the effects of osmotic backwashing were analysed under different total dissolved salts (TDSs) and backwashing conditions, and the parameters of the osmotic backwashing were evaluated. The results of the analysis based on the properties of the organic matters found in raw water showed that the cleaning efficiency in respect to the fouling by hydrophilic organic matters was the greatest. Osmotic backwashing was carried out by changing the TDS of the permeate. As a result, the backwashing volume decreased with time due to the CP of the permeate and the backwashing volume. The difference in the osmotic pressure between the raw water and the permeate (Delta pi) also decreased as time passed. It was confirmed that when the temperature of the effluent was high, both the cleaning efficiency and the backwashing volume, which inpours at the same time, increased. When the circulation flow of the effluent was high, both the cleaning efficiency and the backwashing volume increased.

  13. Skeletal stem cells and their contribution to skeletal fragility

    DEFF Research Database (Denmark)

    Aldahmash, A.

    2016-01-01

    Age-related osteoporotic fractures are major health care problem worldwide and are the result of impaired bone formation, decreased bone mass and bone fragility. Bone formation is accomplished by skeletal stem cells (SSC) that are recruited to bone surfaces from bone marrow microenvironment....... This review discusses targeting SSC to enhance bone formation and to abolish age-related bone fragility in the context of using stem cells for treatment of age-related disorders. Recent studies are presented that have demonstrated that SSC exhibit impaired functions during aging due to intrinsic senescence...

  14. Seismic fragility of nuclear power plant components (Phase 2): A fragility handbook on eighteen components

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.; Kassir, M.K.; Shteyngart, S.

    1991-06-01

    Fragility estimates of seven equipment classes were published in earlier reports. This report presents fragility analysis results from eleven additional equipment categories. The fragility levels are expressed in probabilistic terms. For users' convenience, this concluding report includes a summary of fragility results of all eighteen equipment classes. A set of conversion factors based on judgment is recommended for use of the information for early vintage equipment. The knowledge gained in conducting the Component Fragility Program and similar other programs is expected to provide a new direction for seismic verification and qualification of equipment. 15 refs., 12 tabs

  15. Ameliorative effects of Cnidoscolus aconitifolius on anaemia and ...

    African Journals Online (AJOL)

    This study was designed to evaluate the ameliorative effect of dietary supplementation of Cnidoscolus aconitifolius leaf on anaemia and changes in erythrocyte osmotic fragility in protein energy malnourished rats. Protein energy malnutrition has been associated with anaemia and changes in osmotic fragility, deformability ...

  16. Abnormal neural precursor cell regulation in the early postnatal Fragile X mouse hippocampus.

    Science.gov (United States)

    Sourial, Mary; Doering, Laurie C

    2017-07-01

    The regulation of neural precursor cells (NPCs) is indispensable for a properly functioning brain. Abnormalities in NPC proliferation, differentiation, survival, or integration have been linked to various neurological diseases including Fragile X syndrome. Yet, no studies have examined NPCs from the early postnatal Fragile X mouse hippocampus despite the importance of this developmental time point, which marks the highest expression level of FMRP, the protein missing in Fragile X, in the rodent hippocampus and is when hippocampal NPCs have migrated to the dentate gyrus (DG) to give rise to lifelong neurogenesis. In this study, we examined NPCs from the early postnatal hippocampus and DG of Fragile X mice (Fmr1-KO). Immunocytochemistry on neurospheres showed increased Nestin expression and decreased Ki67 expression, which collectively indicated aberrant NPC biology. Intriguingly, flow cytometric analysis of the expression of the antigens CD15, CD24, CD133, GLAST, and PSA-NCAM showed a decreased proportion of neural stem cells (GLAST + CD15 + CD133 + ) and an increased proportion of neuroblasts (PSA-NCAM + CD15 + ) in the DG of P7 Fmr1-KO mice. This was mirrored by lower expression levels of Nestin and the mitotic marker phospho-histone H3 in vivo in the P9 hippocampus, as well as a decreased proportion of cells in the G 2 /M phases of the P7 DG. Thus, the absence of FMRP leads to fewer actively cycling NPCs, coinciding with a decrease in neural stem cells and an increase in neuroblasts. Together, these results show the importance of FMRP in the developing hippocampal formation and suggest abnormalities in cell cycle regulation in Fragile X. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  17. Direct measurement of osmotic pressure of glycosaminoglycan solutions by membrane osmometry at room temperature.

    Science.gov (United States)

    Chahine, Nadeen O; Chen, Faye H; Hung, Clark T; Ateshian, Gerard A

    2005-09-01

    Articular cartilage is a hydrated soft tissue composed of negatively charged proteoglycans fixed within a collagen matrix. This charge gradient causes the tissue to imbibe water and swell, creating a net osmotic pressure that enhances the tissue's ability to bear load. In this study we designed and utilized an apparatus for directly measuring the osmotic pressure of chondroitin sulfate, the primary glycosaminoglycan found in articular cartilage, in solution with varying bathing ionic strength (0.015 M, 0.15 M, 0.5 M, 1 M, and 2 M NaCl) at room temperature. The osmotic pressure (pi) was found to increase nonlinearly with increasing chondroitin sulfate concentration and decreasing NaCl ionic bath environment. Above 1 M NaCl, pi changes negligibly with further increases in salt concentration, suggesting that Donnan osmotic pressure is negligible above this threshold, and the resulting pressure is attributed to configurational entropy. Results of the current study were also used to estimate the contribution of osmotic pressure to the stiffness of cartilage based on theoretical and experimental considerations. Our findings indicate that the osmotic pressure resulting from configurational entropy is much smaller in cartilage (based on an earlier study on bovine articular cartilage) than in free solution. The rate of change of osmotic pressure with compressive strain is found to contribute approximately one-third of the compressive modulus (H(A)(eff)) of cartilage (Pi approximately H(A)(eff)/3), with the balance contributed by the intrinsic structural modulus of the solid matrix (i.e., H(A) approximately 2H(A)(eff)/3). A strong dependence of this intrinsic modulus on salt concentration was found; therefore, it appears that proteoglycans contribute structurally to the magnitude of H(A), in a manner independent of osmotic pressure.

  18. Osmocapsules for direct measurement of osmotic strength.

    Science.gov (United States)

    Kim, Shin-Hyun; Lee, Tae Yong; Lee, Sang Seok

    2014-03-26

    Monodisperse microcapsules with ultra-thin membranes are microfluidically designed to be highly sensitive to osmotic pressure, thereby providing a tool for the direct measurement of the osmotic strength. To make such osmocapsules, water-in-oil-in-water double-emulsion drops with ultra-thin shells are prepared as templates through emulsification of core-sheath biphasic flow in a capillary microfluidic device. When photocurable monomers are used as the oil phase, the osmocapsules are prepared by in-situ photopolymerization of the monomers, resulting in semipermeable membranes with a relatively large ratio of membrane thickness to capsule radius, approximately 0.02. These osmocapsules are buckled by the outward flux of water when they are subjected to a positive osmotic pressure difference above 125 kPa. By contrast, evaporation-induced consolidation of middle-phase containing polymers enables the production of osmocapsules with a small ratio of membrane thickness to capsule radius of approximately 0.002. Such an ultra-thin membrane with semi-permeability makes the osmocapsules highly sensitive to osmotic pressure; a positive pressure as small as 12.5 kPa induces buckling of the capsules. By employing a set of distinct osmocapsules confining aqueous solutions with different osmotic strengths, the osmotic strength of unknown solutions can be estimated through observation of the capsules that are selectively buckled. This approach provides the efficient measurement of the osmotic strength using only a very small volume of liquid, thereby providing a useful alternative to other measurement methods which use complex setups. In addition, in-vivo measurement of the osmotic strength can be potentially accomplished by implanting these biocompatible osmocapsules into tissue, which is difficult to achieve using conventional methods. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Recycling of osmotic solutions in microwave-osmotic dehydration: product quality and potential for creation of a novel product.

    Science.gov (United States)

    Wray, Derek; Ramaswamy, Hosahalli S

    2016-08-01

    Despite osmotic dehydration being a cost effective process for moisture removal, the cost implications of making, regenerating, and properly disposing of the spent osmotic solutions contributes greatly to the economic feasibility of the drying operation. The potential for recycling of osmotic solutions and their use for creation of a novel product was explored using microwave-osmotic dehydration under continuous flow spray (MWODS) conditions. Identical runs were repeated 10 times to determine the progressive physical and compositional effects of the thermal treatment and leaching from the cranberry samples. The microbiological stability and constant drying performance indicated that MWODS would be well suited for employing recycled solutions. While the anthocyanin content of the solution never approached that of cranberry juice concentrate, it is demonstrated that the spent syrup can infuse these health positive components into another product (apple). This study found that re-using osmotic solutions is a viable option to reduce cost in future MWODS applications, with no detriment to product quality and potential to use the spent solution for novel products. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  20. Xylem diameter changes during osmotic stress, desiccation and freezing in Pinus sylvestris and Populus tremula.

    Science.gov (United States)

    Lintunen, Anna; Lindfors, Lauri; Nikinmaa, Eero; Hölttä, Teemu

    2017-04-01

    Trees experience low apoplastic water potential frequently in most environments. Low apoplastic water potential increases the risk of embolism formation in xylem conduits and creates dehydration stress for the living cells. We studied the magnitude and rate of xylem diameter change in response to decreasing apoplastic water potential and the role of living parenchyma cells in it to better understand xylem diameter changes in different environmental conditions. We compared responses of control and heat-injured xylem of Pinus sylvestris (L.) and Populus tremula (L.) branches to decreasing apoplastic water potential created by osmotic stress, desiccation and freezing. It was shown that xylem in control branches shrank more in response to decreasing apoplastic water potential in comparison with the samples that were preheated to damage living xylem parenchyma. By manipulating the osmotic pressure of the xylem sap, we observed xylem shrinkage due to decreasing apoplastic water potential even in the absence of water tension within the conduits. These results indicate that decreasing apoplastic water potential led to withdrawal of intracellular water from the xylem parenchyma, causing tissue shrinkage. The amount of xylem shrinkage per decrease in apoplastic water potential was higher during osmotic stress or desiccation compared with freezing. During desiccation, xylem diameter shrinkage involved both dehydration-related shrinkage of xylem parenchyma and water tension-induced shrinkage of conduits, whereas dehydration-related shrinkage of xylem parenchyma was accompanied by swelling of apoplastic ice during freezing. It was also shown that the exchange of water between symplast and apoplast within xylem is clearly faster than previously reported between the phloem and the xylem. Time constant of xylem shrinkage was 40 and 2 times higher during osmotic stress than during freezing stress in P. sylvestris and P. tremula, respectively. Finally, it was concluded that the

  1. Fragile X-associated tremor/ataxia syndrome: another phenotype of the fragile X gene.

    Science.gov (United States)

    Hessl, David; Grigsby, Jim

    2016-08-01

    Neuropsychologists have an important role in evaluating patients with fragile X-associated disorders, but most practitioners are unaware of the recently identified neurodegenerative movement disorder known as fragile X-associated tremor ataxia syndrome (FXTAS). The objective of this editorial is to orient the reader to FXTAS and highlight the importance of clinical neuropsychology in describing the fragile X premutation phenotype and the role practitioners may have in assessing and monitoring patients with or at risk for neurodegeneration. We issued a call for papers for the special issue, highlighting the primary objective of familiarizing clinical neuropsychologists with FXTAS, and with the neuropsychological phenotype of both male and female asymptomatic carriers. Eight papers are included, including an overview of the fragile X-associated disorders (Grigsby), a review of the neuroradiological and neurological aspects of FXTAS and how the disorder compares to other movement disorders (O'Keefe et al.), a perspective on the prominence of white matter disease and dementia in FXTAS (Filley), and a review of mouse models of FXTAS (Foote). There are four research papers, including one on self-reported memory problems in FXTAS (Birch et al.), and three papers focused on the neuropsychiatric aspects of the fragile X premutation, a review (Bourgeois), an examination of autism-related traits (Schneider), and a research paper on executive functioning and psychopathology (Grigsby). The issue highlights the importance of awareness of fragile X-associated disorders for neuropsychologists, an awareness that must reach beyond neurodevelopmental aspects related to fragile X syndrome into the realm of neurodegenerative disease and aging.

  2. The effect of atom mismatch on the fragility of supercooled Lennard-Jones binary mixtures

    International Nuclear Information System (INIS)

    Sun Minhua; Sun Yongli; Wang Aiping; Ma Congxiao; Li Jiayun; Cheng Weidong; Liu Fang

    2006-01-01

    The shear viscosity of the well-known binary Lennard-Jones mixture is simulated under constant temperature and constant volume conditions (NVT) by a molecular-dynamics (MD) method. The effect of atomic size mismatch on the fragility parameter and glass-forming ability is studied. The fragility parameters calculated from shear viscosity data decrease with the increment of the atomic size mismatch. The value of the fragility changes from 168.963 to 22.976 when the mismatch changes from 0.023 to 0.25. It is shown that the fragility parameter is sensitive to the atomic size mismatch. The calculated pair distribution functions and mean square displacements indicate that the glass-forming ability increases with the atomic size mismatch

  3. Alterations in the colonic microbiota in response to osmotic diarrhea.

    Science.gov (United States)

    Gorkiewicz, Gregor; Thallinger, Gerhard G; Trajanoski, Slave; Lackner, Stefan; Stocker, Gernot; Hinterleitner, Thomas; Gülly, Christian; Högenauer, Christoph

    2013-01-01

    Diseases of the human gastrointestinal (GI) tract are often accompanied by diarrhea with profound alterations in the GI microbiota termed dysbiosis. Whether dysbiosis is due to the disease itself or to the accompanying diarrhea remains elusive. With this study we characterized the net effects of osmotic diarrhea on the composition of the GI microbiota in the absence of disease. We induced osmotic diarrhea in four healthy adults by oral administration of polyethylene glycol 4000 (PEG). Stool as well as mucosa specimens were collected before, during and after diarrhea and 16S rDNA-based microbial community profiling was used to assess the microbial community structure. Stool and mucosal microbiotas were strikingly different, with Firmicutes dominating the mucosa and Bacteroidetes the stools. Osmotic diarrhea decreased phylotype richness and showed a strong tendency to equalize the otherwise individualized microbiotas on the mucosa. Moreover, diarrhea led to significant relative shifts in the phyla Bacteroidetes and Firmicutes and to a relative increase in the abundance of Proteobacteria on the mucosa, a phenomenon also noted in several inflammatory and diarrheal GI diseases. Changes in microbial community structure induced by osmotic diarrhea are profound and show similarities to changes observed in other GI diseases including IBD. These effects so must be considered when specimens from diarrheal diseases (i.e. obtained by stratification of samples according to diarrheal status) or conditions wherein bowel preparations like PEG (i.e. specimens obtained during endoscopy) are used.

  4. Alterations in the colonic microbiota in response to osmotic diarrhea.

    Directory of Open Access Journals (Sweden)

    Gregor Gorkiewicz

    Full Text Available BACKGROUND & AIMS: Diseases of the human gastrointestinal (GI tract are often accompanied by diarrhea with profound alterations in the GI microbiota termed dysbiosis. Whether dysbiosis is due to the disease itself or to the accompanying diarrhea remains elusive. With this study we characterized the net effects of osmotic diarrhea on the composition of the GI microbiota in the absence of disease. METHODS: We induced osmotic diarrhea in four healthy adults by oral administration of polyethylene glycol 4000 (PEG. Stool as well as mucosa specimens were collected before, during and after diarrhea and 16S rDNA-based microbial community profiling was used to assess the microbial community structure. RESULTS: Stool and mucosal microbiotas were strikingly different, with Firmicutes dominating the mucosa and Bacteroidetes the stools. Osmotic diarrhea decreased phylotype richness and showed a strong tendency to equalize the otherwise individualized microbiotas on the mucosa. Moreover, diarrhea led to significant relative shifts in the phyla Bacteroidetes and Firmicutes and to a relative increase in the abundance of Proteobacteria on the mucosa, a phenomenon also noted in several inflammatory and diarrheal GI diseases. CONCLUSIONS: Changes in microbial community structure induced by osmotic diarrhea are profound and show similarities to changes observed in other GI diseases including IBD. These effects so must be considered when specimens from diarrheal diseases (i.e. obtained by stratification of samples according to diarrheal status or conditions wherein bowel preparations like PEG (i.e. specimens obtained during endoscopy are used.

  5. Mechanisms of diabetes mellitus-induced bone fragility.

    Science.gov (United States)

    Napoli, Nicola; Chandran, Manju; Pierroz, Dominique D; Abrahamsen, Bo; Schwartz, Ann V; Ferrari, Serge L

    2017-04-01

    The risk of fragility fractures is increased in patients with either type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM). Although BMD is decreased in T1DM, BMD in T2DM is often normal or even slightly elevated compared with an age-matched control population. However, in both T1DM and T2DM, bone turnover is decreased and the bone material properties and microstructure of bone are altered; the latter particularly so when microvascular complications are present. The pathophysiological mechanisms underlying bone fragility in diabetes mellitus are complex, and include hyperglycaemia, oxidative stress and the accumulation of advanced glycation endproducts that compromise collagen properties, increase marrow adiposity, release inflammatory factors and adipokines from visceral fat, and potentially alter the function of osteocytes. Additional factors including treatment-induced hypoglycaemia, certain antidiabetic medications with a direct effect on bone and mineral metabolism (such as thiazolidinediones), as well as an increased propensity for falls, all contribute to the increased fracture risk in patients with diabetes mellitus.

  6. Self-assembly of silk fibroin under osmotic stress

    Science.gov (United States)

    Sohn, Sungkyun

    The supramolecular self-assembly behavior of silk fibroin was investigated using osmotic stress technique. In Chapter 2, a ternary phase diagram of water-silk-LiBr was constructed based on X-ray results on the osmotically stressed regenerated silk fibroin of Bombyx mori silkworm. Microscopic data indicated that silk I is a hydrated structure and a rough estimate of the number of water molecules lost by the structure upon converting from silk I to silk II has been made, and found to be about 2.2 per [GAGAGS] hexapeptide. In Chapter 3, wet-spinning of osmotically stressed, regenerated silk fibroin was performed, based on the prediction that the enhanced control over structure and phase behavior using osmotic stress method helps improve the physical properties of wet-spun regenerated silk fibroin fibers. The osmotic stress was applied in order to pre-structure the regenerated silk fibroin molecule from its original random coil state to more oriented state, manipulating the phase of the silk solution in the phase diagram before the start of spinning. Monofilament fiber with a diameter of 20 microm was produced. In Chapter 4, we investigated if there is a noticeable synergistic osmotic pressure increase between co-existing polymeric osmolyte and salt when extremely highly concentrated salt molecules are present both at sample subphase and stressing subphase, as is the case of silk fibroin self-assembly. The equilibration method that measures osmotic pressure relative to a reference with known osmotic pressure was introduced. Osmotic pressure of aqueous LiBr solution up to 2.75M was measured and it was found that the synergistic effect was insignificant up to this salt concentration. Solution parameters of stressing solutions and Arrhenius kinetics based on time-temperature relationship for the equilibration process were derived as well. In Chapter 5, self-assembly behavior of natural silk fibroin within the gland of Bombyx mori silkworm was investigated using osmotic

  7. Does Osmotic Stress Affect Natural Product Expression in Fungi?

    Science.gov (United States)

    Overy, David; Correa, Hebelin; Roullier, Catherine; Chi, Wei-Chiung; Pang, Ka-Lai; Rateb, Mostafa; Ebel, Rainer; Shang, Zhuo; Capon, Rob; Bills, Gerald; Kerr, Russell

    2017-08-13

    The discovery of new natural products from fungi isolated from the marine environment has increased dramatically over the last few decades, leading to the identification of over 1000 new metabolites. However, most of the reported marine-derived species appear to be terrestrial in origin yet at the same time, facultatively halo- or osmotolerant. An unanswered question regarding the apparent chemical productivity of marine-derived fungi is whether the common practice of fermenting strains in seawater contributes to enhanced secondary metabolism? To answer this question, a terrestrial isolate of Aspergillus aculeatus was fermented in osmotic and saline stress conditions in parallel across multiple sites. The ex-type strain of A. aculeatus was obtained from three different culture collections. Site-to-site variations in metabolite expression were observed, suggesting that subculturing of the same strain and subtle variations in experimental protocols can have pronounced effects upon metabolite expression. Replicated experiments at individual sites indicated that secondary metabolite production was divergent between osmotic and saline treatments. Titers of some metabolites increased or decreased in response to increasing osmolite (salt or glycerol) concentrations. Furthermore, in some cases, the expression of some secondary metabolites in relation to osmotic and saline stress was attributed to specific sources of the ex-type strains.

  8. Fragility of chalcogenide glass in relation to characteristic temperature T0/Tg

    Science.gov (United States)

    Shaker, A. M.; Shanker Rao, T.; Lilly Shanker Rao, T.; Venkataraman, K.

    2018-03-01

    The present study reports the mutual relationship between the fragility index m and the characteristic temperature T0/Tg. The fragility of the chalcogenide amorphous glass of Ge10Se50Te40 is calculated by utilizing glass transition temperature (Tg) measured by DSC (Differential Scanning Calorimetry) at different heating rates (β) in the range 5 to 20 K/min. Vogel-Fulcher-Tammann (VFT) equation is fitted to the data of Tg. In addition to the VFT method, three other methods are also used to evaluate m. The fragility index m of the Ge10Se50Te40 system showed the trend of decrease with increasing heating rate but remained stable around 22 for the heating rate 10 K/min. The value of m for the glass is near the lower limit (m ≈ 16) this indicates the alloy is a strong glass forming material in accordance of Angell’s interpretation of fragility. The calculated values of characteristic temperature T0/Tg is very close to 1 which also indicates that clearly the system is most fragile.

  9. Molecular sieving action of the cell membrane during gradual osmotic hemolysis

    Energy Technology Data Exchange (ETDEWEB)

    MacGregor, R.D. II

    1977-05-01

    Rat erythrocytes were hemolyzed by controlled gradual osmotic hemolysis to study cell morphology and hemoglobin loss from individual cells. Results suggest that each increase in the rate of loss of a protein from the cells during the initial phases of controlled gradual osmotic hemolysis is caused by the passage of a previously impermeable species across the stressed membrane. Similarly, during the final stages of controlled gradual osmotic hemolysis, each sharp decrease in the rate of loss of a protein corresponds to the termination of a molecular flow. A theoretical model is described that predicts the molecular sieving of soluble globular proteins across the stressed red cell membrane. Hydrophobic interactions occur between the soluble proteins and the lipid bilayer portion of the cell membrane. A spectrin network subdivides the bilayer into domains that restrict the insertion of large molecules into the membrane. Other membrane proteins affect soluble protein access to the membrane. Changes in the loss curves caused by incubation of red cells are discussed in terms of the model.

  10. Controlling Release of Integral Lipid Nanoparticles Based on Osmotic Pump Technology.

    Science.gov (United States)

    Tian, Zhiqiang; Yu, Qin; Xie, Yunchang; Li, Fengqian; Lu, Yi; Dong, Xiaochun; Zhao, Weili; Qi, Jianping; Wu, Wei

    2016-08-01

    To achieve controlled release of integral nanoparticles by the osmotic pump strategy using nanostructured lipid carriers (NLCs) as model nanoparticles. NLCs was prepared by a hot-homogenization method, transformed into powder by lyophilization, and formulated into osmotic pump tablets (OPTs). Release of integral NLCs was visualized by live imaging after labeling with a water-quenching fluorescent probe. Effects of formulation variables on in vitro release characteristics were evaluated by measuring the model drug fenofibrate. Pharmacokinetics were studied in beagle dogs using the core tablet and a micronized fenofibrate formulation as references. NLCs are released through the release orifices of the OPTs as integral nanoparticles. Near zero-order kinetics can be achieved by optimizing the influencing variables. After oral administration, decreased C max and steady drug levels for as long as over 24 h are observed. NLC-OPTs show an oral bioavailability of the model drug fenofibrate similar to that of the core tablets, which is about 1.75 folds that of a fast-release formulation. Controlled release of integral NLCs is achieved by the osmotic pump strategy.

  11. Colloid osmotic pressure during and after surgical interventions in adult and geriatric dogs

    Directory of Open Access Journals (Sweden)

    Mario A.F. Rego

    Full Text Available ABSTRACT: The objective this study is to evaluate colloid osmotic pressure (COP fluctuations in adult and senile dogs during surgical interventions. Thirty-six healthy dogs to surgical interventions, distributed in two groups, A and B, according to their age, and were all subjected to the same anesthetic protocol. Values of albumin, total plasmatic protein and COP were evaluated from samples collected before pre-anesthetic medication, fifteen minutes after pre-anesthetic medication, and shortly after the end of the intervention. Results were tested using t-test to compare among groups and ANOVA for repeated measures followed by Tukey’s test to compare different moments within the same group. Statistical significance was set at p<0.05. In both groups, significant decreases were observed in colloid osmotic pressure, as well as albumin and total proteins (p<0.001. Despite slightly lower COP values for the group of adult animals, this difference was not significant as there was a high individual variation within groups. The results therefore indicate no difference in colloid osmotic pressure values or fluctuation patterns among adult and senile dogs (p=0.124. The observed results indicate that colloid osmotic pressure decreases significantly during surgical procedures, due to hypotension caused by the anesthetic drugs and to hemodilution caused by the fluid administration but there is no difference between groups. However, in both adult and senile dogs, these variables recover gradually after the animals awaken, through increased urine production and recovery of vascular tonus, indicating the successful reestablishment of homeostasis.

  12. PEG-induced osmotic stress in Mentha x piperita L.: Structural features and metabolic responses.

    Science.gov (United States)

    Búfalo, Jennifer; Rodrigues, Tatiane Maria; de Almeida, Luiz Fernando Rolim; Tozin, Luiz Ricardo Dos Santos; Marques, Marcia Ortiz Mayo; Boaro, Carmen Silvia Fernandes

    2016-08-01

    The present study investigated whether osmotic stress induced by the exposure of peppermint (Mentha x piperita L.) to moderate and severe stress for short periods of time changes the plant's physiological parameters, leaf anatomy and ultrastructure and essential oil. Plants were exposed to two levels of polyethyleneglycol (50 g L(-1) and 100 g L(-1) of PEG) in a hydroponic experiment. The plants exposed to 50 g L(-1) maintained metabolic functions similar to those of the control group (0 g L(-1)) without changes in gas exchange or structural characteristics. The increase in antioxidant enzyme activity reduced the presence of free radicals and protected membranes, including chloroplasts and mitochondria. In contrast, the osmotic stress caused by 100 g L(-1) of PEG inhibited leaf gas exchange, reduced the essential oil content and changed the oil composition, including a decrease in menthone and an increase in menthofuran. These plants also showed an increase in peroxidase activity, but this increase was not sufficient to decrease the lipid peroxidation level responsible for damaging the membranes of organelles. Morphological changes were correlated with the evaluated physiological features: plants exposed to 100 g L(-1) of PEG showed areas with collapsed cells, increases in mesophyll thickness and the area of the intercellular space, cuticle shrinkage, morphological changes in plastids, and lysis of mitochondria. In summary, our results revealed that PEG-induced osmotic stress in M. x piperita depends on the intensity level of the osmotic stress applied; severe osmotic stress changed the structural characteristics, caused damage at the cellular level, and reduced the essential oil content and quality. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  13. Genetics Home Reference: fragile X syndrome

    Science.gov (United States)

    ... Facebook Twitter Home Health Conditions Fragile X syndrome Fragile X syndrome Printable PDF Open All Close All Enable Javascript to view the expand/collapse boxes. Description Fragile X syndrome is a genetic condition that causes a ...

  14. Casein Micelle Dispersions under Osmotic Stress

    Science.gov (United States)

    Bouchoux, Antoine; Cayemitte, Pierre-Emerson; Jardin, Julien; Gésan-Guiziou, Geneviève; Cabane, Bernard

    2009-01-01

    Abstract Casein micelles dispersions have been concentrated and equilibrated at different osmotic pressures using equilibrium dialysis. This technique measured an equation of state of the dispersions over a wide range of pressures and concentrations and at different ionic strengths. Three regimes were found. i), A dilute regime in which the osmotic pressure is proportional to the casein concentration. In this regime, the casein micelles are well separated and rarely interact, whereas the osmotic pressure is dominated by the contribution from small residual peptides that are dissolved in the aqueous phase. ii), A transition range that starts when the casein micelles begin to interact through their κ-casein brushes and ends when the micelles are forced to get into contact with each other. At the end of this regime, the dispersions behave as coherent solids that do not fully redisperse when osmotic stress is released. iii), A concentrated regime in which compression removes water from within the micelles, and increases the fraction of micelles that are irreversibly linked to each other. In this regime the osmotic pressure profile is a power law of the residual free volume. It is well described by a simple model that considers the micelle to be made of dense regions separated by a continuous phase. The amount of water in the dense regions matches the usual hydration of proteins. PMID:19167314

  15. Aquaporin-mediated increase in root hydraulic conductance is involved in silicon-induced improved root water uptake under osmotic stress in Sorghum bicolor L.

    Science.gov (United States)

    Liu, Peng; Yin, Lina; Deng, Xiping; Wang, Shiwen; Tanaka, Kiyoshi; Zhang, Suiqi

    2014-09-01

    The fact that silicon application alleviates water deficit stress has been widely reported, but the underlying mechanism remains unclear. Here the effects of silicon on water uptake and transport of sorghum seedlings (Sorghum bicolor L.) growing under polyethylene glycol-simulated osmotic stress in hydroponic culture and water deficit stress in sand culture were investigated. Osmotic stress dramatically decreased dry weight, photosynthetic rate, transpiration rate, stomatal conductance, and leaf water content, but silicon application reduced these stress-induced decreases. Although silicon application had no effect on stem water transport capacity, whole-plant hydraulic conductance (Kplant) and root hydraulic conductance (Lp) were higher in silicon-treated seedlings than in those without silicon treatment under osmotic stress. Furthermore, the extent of changes in transpiration rate was similar to the changes in Kplant and Lp. The contribution of aquaporin to Lp was characterized using the aquaporin inhibitor mercury. Under osmotic stress, the exogenous application of HgCl2 decreased the transpiration rates of seedlings with and without silicon to the same level; after recovery induced by dithiothreitol (DTT), however, the transpiration rate was higher in silicon-treated seedlings than in untreated seedlings. In addition, transcription levels of several root aquaporin genes were increased by silicon application under osmotic stress. These results indicate that the silicon-induced up-regulation of aquaporin, which was thought to increase Lp, was involved in improving root water uptake under osmotic stress. This study also suggests that silicon plays a modulating role in improving plant resistance to osmotic stress in addition to its role as a mere physical barrier. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  16. Osmotic dehydration of fruits and vegetables: a review.

    Science.gov (United States)

    Yadav, Ashok Kumar; Singh, Satya Vir

    2014-09-01

    The main cause of perishability of fruits and vegetables are their high water content. To increase the shelf life of these fruits and vegetables many methods or combination of methods had been tried. Osmotic dehydration is one of the best and suitable method to increase the shelf life of fruits and vegetables. This process is preferred over others due to their vitamin and minerals, color, flavor and taste retention property. In this review different methods, treatments, optimization and effects of osmotic dehydration have been reviewed. Studied showed that combination of different osmotic agents were more effective than sucrose alone due to combination of properties of solutes. During the experiments it was found that optimum osmosis was found at approximately 40 °C, 40 °B of osmotic agent and in near about 132 min. Pretreatments also leads to increase the osmotic process in fruits and vegetables. Mass transfer kinetics study is an important parameter to study osmosis. Solids diffusivity were found in wide range (5.09-32.77 kl/mol) studied by Fick's laws of diffusion. These values vary depending upon types of fruits and vegetables and osmotic agents.

  17. Effect of Osmotic Stress on Seed Germination Indices of Nigella sativa and Silybum marianum

    Directory of Open Access Journals (Sweden)

    H Balouchi

    2012-04-01

    Full Text Available Evaluation of medicinal plants to drought and salt stress tolerance, in an attempt to plant them under drought and saline regions, is of utmost importance. Environmental stresses, especially drought and salt, reduce the global crop yields more than other factors. Selection of drought tolerant crops at germination stage, usually is, the fast and low cost method. In order to study the effect of osmotic stress on germination indices of black cumin and milk thistle, an experiment carried out in a completely randomized design with four replications at the Seed Technology Laboratoary of Yasouj University in 2008. Treatments were 0 (as control, -2.4, -4.8, -7.2 and -9.4 bar osmotic potentials created by using PEG 6000. Results showed that, decreasing of osmotic potential reduced speed of germination and its percentage, root and shoot lengths and dry matter in these two plants. Black cumin showed higher tolerance, to -4.8 bar osmotic potential, as compared to milk thistle. However, milk thistle showed higher tolerance to drought stress, up to this osmotic potential (-4.8 bar, compared to black cumin. Milk thistle had lower germination speed and percentage at higher drought stress as compared to black cumin. Generally, milk thistle showed better growth and survival than black cumin due to its higher root and shoot length and dry matter.

  18. The plant cuticle is required for osmotic stress regulation of abscisic acid biosynthesis and osmotic stress tolerance in Arabidopsis

    KAUST Repository

    Wang, Zhenyu; Xiong, Liming; Li, Wenbo; Zhu, Jian-Kang; Zhu, Jianhua

    2011-01-01

    Osmotic stress activates the biosynthesis of abscisic acid (ABA). One major step in ABA biosynthesis is the carotenoid cleavage catalyzed by a 9-cis epoxycarotenoid dioxygenase (NCED). To understand the mechanism for osmotic stress activation of ABA

  19. Prevalence and factors associated with fragility syndrome in older adults attending

    Directory of Open Access Journals (Sweden)

    Milton Carlos Gonzáles-Mechán

    2017-03-01

    Full Text Available Objectives: To identify the prevalence and factors associated with fragility syndrome in older adults attending the EsSalud (Peruvian Social Security Health Insurance primary health care service, Chiclayo - Peru. Materials and methods: A descriptive, prospective and cross-sectional study was conducted on a sample consisting of 326 older adults from urban areas and surrounding districts of Chiclayo, who attend the outpatient service at the Hospital Naylamp and Policlínico Chiclayo Oeste. A data collection sheet including social-demographic variables, comorbidity and polypharmacy, and fragility syndrome clinical criteria was filled in. Results: The prevalence of fragility was 17.5% and that of pre-fragility, 40.9%. The most frequent fragility clinical criteria were as follows: self-reported fatigue (42.3% and decreased grip strength (32.8%. The bivariate analysis showed an association with age, level of education, occupation (class IV and V concerning manual work, comorbidity (class II, asymptomatic disease or asymptomatic disease that requires medication but is under control, polypharmacy, anemia, Parkinson’s disease and non-vascular neurological disease. The final prediction model covering the age (1.08, 95% CI: 1.03 to 1.12, higher education level as a preventive variable (0.21, 95% CI: 0.07 to 0.62, type II comorbidity (11 08, 95% CI: 1.45 to 84.38 and polypharmacy (2.49, 95% CI: 1.24 to 5.03 predicts the likelihood of fragility syndrome in 75.6%. Conclusions: There is a high prevalence of fragility in the elderly population attending the primary health care service, and a significant association with age, higher education level, type II comorbidity and polypharmacy

  20. Systems fragility: The sociology of chaos.

    Science.gov (United States)

    Hodges, Lori R

    2016-01-01

    This article examines the concept of community fragility in emergency management from a systems perspective. Using literature that addresses fragility in four areas of complex systems, including ecosystems, social systems, sociotechnical systems, and complex adaptive systems, a theoretical framework focused on the emergency management field is created. These findings illustrate how community fragility factors can be used in the emergency management field to not only improve overall outcomes after disaster but also build less fragile systems and communities in preparation for future disasters.

  1. Manipulations of attention dissociate fragile visual short-term memory from visual working memory.

    Science.gov (United States)

    Vandenbroucke, Annelinde R E; Sligte, Ilja G; Lamme, Victor A F

    2011-05-01

    People often rely on information that is no longer in view, but maintained in visual short-term memory (VSTM). Traditionally, VSTM is thought to operate on either a short time-scale with high capacity - iconic memory - or a long time scale with small capacity - visual working memory. Recent research suggests that in addition, an intermediate stage of memory in between iconic memory and visual working memory exists. This intermediate stage has a large capacity and a lifetime of several seconds, but is easily overwritten by new stimulation. We therefore termed it fragile VSTM. In previous studies, fragile VSTM has been dissociated from iconic memory by the characteristics of the memory trace. In the present study, we dissociated fragile VSTM from visual working memory by showing a differentiation in their dependency on attention. A decrease in attention during presentation of the stimulus array greatly reduced the capacity of visual working memory, while this had only a small effect on the capacity of fragile VSTM. We conclude that fragile VSTM is a separate memory store from visual working memory. Thus, a tripartite division of VSTM appears to be in place, comprising iconic memory, fragile VSTM and visual working memory. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Alternative oxidase pathway optimizes photosynthesis during osmotic and temperature stress by regulating cellular ROS, malate valve and antioxidative systems

    Directory of Open Access Journals (Sweden)

    DINAKAR eCHALLABATHULA

    2016-02-01

    Full Text Available The present study reveals the importance of alternative oxidase (AOX pathway in optimizing photosynthesis under osmotic and temperature stress conditions in the mesophyll protoplasts of Pisum sativum. The responses of photosynthesis and respiration were monitored at saturating light intensity of 1000 µmoles m-2 s-1 at 25 oC under a range of sorbitol concentrations from 0.4 M to 1.0M to induce hyper-osmotic stress and by varying the temperature of the thermo-jacketed pre-incubation chamber from 25 oC to 10 oC to impose sub-optimal temperature stress. Compared to controls (0.4 M sorbitol and 25 OC, the mesophyll protoplasts showed remarkable decrease in NaHCO3-dependent O2 evolution (indicator of photosynthetic carbon assimilation, under both hyper-osmotic (1.0 M sorbitol and sub-optimal temperature stress conditions (10 OC, while the decrease in rates of respiratory O2 uptake were marginal. The capacity of AOX pathway increased significantly in parallel to increase in intracellular pyruvate and reactive oxygen species (ROS levels under both hyper-osmotic stress and sub-optimal temperature stress under the background of saturating light. The ratio of redox couple (Malate/OAA related to malate valve increased in contrast to the ratio of redox couple (GSH/GSSG related to antioxidative system during hyper-osmotic stress. Nevertheless, the ratio of GSH/GSSG decreased in the presence of sub-optimal temperature, while the ratio of Malate/OAA showed no visible changes. Also, the redox ratios of pyridine nucleotides increased under hyper-osmotic (NADH/NAD and sub-optimal temperature (NADPH/NADP stresses, respectively. However, upon restriction of AOX pathway by using salicylhydroxamic acid (SHAM, the observed changes in NaHCO3 dependent O2 evolution, cellular ROS, redox ratios of Malate/OAA, NAD(PH/NAD(P and GSH/GSSG were further aggravated under stress conditions with concomitant modulations in NADP-MDH and antioxidant enzymes. Taken together, the

  3. Association between change in BMD and fragility fracture in women and men.

    Science.gov (United States)

    Berger, Claudie; Langsetmo, Lisa; Joseph, Lawrence; Hanley, David A; Davison, K Shawn; Josse, Robert G; Prior, Jerilynn C; Kreiger, Nancy; Tenenhouse, Alan; Goltzman, David

    2009-02-01

    Our objective was to estimate the relationship between longitudinal change in BMD and fragility fractures. We studied 3635 women and 1417 men 50-85 yr of age in the Canadian Multicentre Osteoporosis Study who had at least two BMD measurements (lumbar spine, femoral neck, total hip, and trochanter) within the first 5 yr of the study and fragility fractures (any, main, forearm/wrist, ribs, hip) within the first 7 yr. Multiple logistic regression was used to model the relationship between baseline BMD, BMD change, and fragility fractures. We found that, among nonusers of antiresorptives, independent of baseline BMD, a decrease of 0.01 g/cm(2)/yr in total hip BMD was associated with an increased risk of fragility fracture with ORs of 1.15 (95% CI: 1.01; 1.32) in women and 1.34 (95% CI: 1.02; 1.78) in men. The risk of fragility fractures in subgroups such as fast losers and those with osteopenia was better estimated by models that included BMD change than by models that included baseline BMD but excluded BMD change. Although the association between baseline BMD and fragility fractures was similar in users and nonusers of antiresorptives, the association was stronger in nonusers compared with users. These results show that BMD change in both men and women is an independent risk factor for fragility fractures and also predicts fracture risk in those with osteopenia. The results suggest that BMD change should be included with other variables in a comprehensive fracture prediction model to capture its contribution to osteoporotic fracture risk.

  4. Fragile X syndrome and fragile X-associated disorders [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Akash Rajaratnam

    2017-12-01

    Full Text Available Fragile X syndrome (FXS is caused by a full mutation on the FMR1 gene and a subsequent lack of FMRP, the protein product of FMR1. FMRP plays a key role in regulating the translation of many proteins involved in maintaining neuronal synaptic connections; its deficiency may result in a range of intellectual disabilities, social deficits, psychiatric problems, and dysmorphic physical features. A range of clinical involvement is also associated with the FMR1 premutation, including fragile X-associated tremor ataxia syndrome, fragile X-associated primary ovarian insufficiency, psychiatric problems, hypertension, migraines, and autoimmune problems. Over the past few years, there have been a number of advances in our knowledge of FXS and fragile X-associated disorders, and each of these advances offers significant clinical implications. Among these developments are a better understanding of the clinical impact of the phenomenon known as mosaicism, the revelation that various types of mutations can cause FXS, and improvements in treatment for FXS.

  5. Ion and solvent Transport in Polypyrrole: Experimental Test of Osmotic Model

    DEFF Research Database (Denmark)

    Velmurugu, Yogambigai; Skaarup, Steen

    2005-01-01

    Ion and solvent transport in the conjugated polymer actuator material, polypyrrole, doped with the immobile anion dodecyl benzene sulphonate, has been investigated by simultaneous cyclic voltammetry and Electrochemical Quartz Crystal Microbalance measurements. The purpose was to elucidate the pre...... from almost pure cation transport to ca. equal amount of anion transport; exchanging Br- for Cl- ions has only negligible effect at lower concentrations at equal osmotic pressures. Ca. 4 H2O molecules are tightly bound to each Na+ ion at concentrations ... the precise nature of the mobile species during redox cycling, and to seek confirmation for the osmotic mechanism of actuation. Three testable aspects of the model were confirmed: The number of inserted H2O molecules decreases with electrolyte concentration; at the same time the mechanism gradually changes...

  6. Alleviation of Osmotic Stress Effects by Exogenous Application of Salicylic or Abscisic Acid on Wheat Seedlings

    Science.gov (United States)

    Marcińska, Izabela; Czyczyło-Mysza, Ilona; Skrzypek, Edyta; Grzesiak, Maciej T.; Janowiak, Franciszek; Filek, Maria; Dziurka, Michał; Dziurka, Kinga; Waligórski, Piotr; Juzoń, Katarzyna; Cyganek, Katarzyna; Grzesiak, Stanisław

    2013-01-01

    The aim of the study was to assess the role of salicylic acid (SA) and abscisic acid (ABA) in osmotic stress tolerance of wheat seedlings. This was accomplished by determining the impact of the acids applied exogenously on seedlings grown under osmotic stress in hydroponics. The investigation was unique in its comprehensiveness, examining changes under osmotic stress and other conditions, and testing a number of parameters simultaneously. In both drought susceptible (SQ1) and drought resistant (CS) wheat cultivars, significant physiological and biochemical changes were observed upon the addition of SA (0.05 mM) or ABA (0.1 μM) to solutions containing half-strength Hoagland medium and PEG 6000 (−0.75 MPa). The most noticeable result of supplementing SA or ABA to the medium (PEG + SA and PEG + ABA) was a decrease in the length of leaves and roots in both cultivars. While PEG treatment reduced gas exchange parameters, chlorophyll content in CS, and osmotic potential, and conversely, increased lipid peroxidation, soluble carbohydrates in SQ1, proline content in both cultivars and total antioxidants activity in SQ1, PEG + SA or PEG + ABA did not change the values of these parameters. Furthermore, PEG caused a two-fold increase of endogenous ABA content in SQ1 and a four-fold increase in CS. PEG + ABA increased endogenous ABA only in SQ1, whereas PEG + SA caused a greater increase of ABA content in both cultivars compared to PEG. In PEG-treated plants growing until the harvest, a greater decrease of yield components was observed in SQ1 than in CS. PEG + SA, and particularly PEG + ABA, caused a greater increase of these yield parameters in CS compared to SQ1. In conclusion, SA and ABA ameliorate, particularly in the tolerant wheat cultivar, the harmful effects and after effects of osmotic stress induced by PEG in hydroponics through better osmotic adjustment achieved by an increase in proline and carbohydrate content as well as by an increase in antioxidant activity

  7. Alleviation of Osmotic Stress Effects by Exogenous Application of Salicylic or Abscisic Acid on Wheat Seedlings

    Directory of Open Access Journals (Sweden)

    Katarzyna Cyganek

    2013-06-01

    Full Text Available The aim of the study was to assess the role of salicylic acid (SA and abscisic acid (ABA in osmotic stress tolerance of wheat seedlings. This was accomplished by determining the impact of the acids applied exogenously on seedlings grown under osmotic stress in hydroponics. The investigation was unique in its comprehensiveness, examining changes under osmotic stress and other conditions, and testing a number of parameters simultaneously. In both drought susceptible (SQ1 and drought resistant (CS wheat cultivars, significant physiological and biochemical changes were observed upon the addition of SA (0.05 mM or ABA (0.1 μM to solutions containing half-strength Hoagland medium and PEG 6000 (−0.75 MPa. The most noticeable result of supplementing SA or ABA to the medium (PEG + SA and PEG + ABA was a decrease in the length of leaves and roots in both cultivars. While PEG treatment reduced gas exchange parameters, chlorophyll content in CS, and osmotic potential, and conversely, increased lipid peroxidation, soluble carbohydrates in SQ1, proline content in both cultivars and total antioxidants activity in SQ1, PEG + SA or PEG + ABA did not change the values of these parameters. Furthermore, PEG caused a two-fold increase of endogenous ABA content in SQ1 and a four-fold increase in CS. PEG + ABA increased endogenous ABA only in SQ1, whereas PEG + SA caused a greater increase of ABA content in both cultivars compared to PEG. In PEG-treated plants growing until the harvest, a greater decrease of yield components was observed in SQ1 than in CS. PEG + SA, and particularly PEG + ABA, caused a greater increase of these yield parameters in CS compared to SQ1. In conclusion, SA and ABA ameliorate, particularly in the tolerant wheat cultivar, the harmful effects and after effects of osmotic stress induced by PEG in hydroponics through better osmotic adjustment achieved by an increase in proline and carbohydrate content as well as by an increase in antioxidant

  8. The Evaluation of Corneal Fragility After UVA/Riboflavin Crosslinking.

    Science.gov (United States)

    Li, Zhiwei; Wang, Yumeng; Xu, Yanyun; Jhanji, Vishal; Zhang, Chunxiao; Mu, Guoying

    2017-03-01

    To evaluate the fragility of cornea after UVA/riboflavin crosslinking (CXL). Sixty New Zealand rabbits received UVA/riboflavin crosslinking treatment (wavelength 365 nm, irradiance 3.0 mW/cm, and total dose 5.4 J/cm) on right eyes. Animals were sacrificed before and immediately after treatment (day 0), day 1, 3, 7, and 28 after treatment. A 4×10 mm corneal strip for biomechanical evaluation was harvested after sacrifice. The corneal fragility was evaluated by measurement of elongation rate, whereby the elongation rate equals elongation length/baseline length. The Youngs modulus and maximal stress were 1.41±0.51 MPa and 5.56±1.84 MPa before CXL, and increased to 2.31±0.68 MPa (P=0.008) and 9.25±2.74 MPa (P=0.04), respectively, on day 0, then maintained a stable level within a 28 days follow-up. The elongation rate was 62.04±9.34% before CXL and decreased to 48.95%±8.24% (P=0.02) on day 0, then maintained a stable level within a 28 days follow-up. This study showed an increase in the corneal fragility after UVA/riboflavin crosslinking along with an increase in the corneal stiffness. A long-term follow-up should be taken to evaluate the potential deleterious effect of the increasing corneal fragility after UVA/riboflavin crosslinking.

  9. Three Faces of Fragile X.

    Science.gov (United States)

    Lieb-Lundell, Cornelia C E

    2016-11-01

    Fragile X syndrome (FXS) is the first of 3 syndromes identified as a health condition related to fragile X mental retardation (FMR1) gene dysfunction. The other 2 syndromes are fragile X-associated primary ovarian insufficiency syndrome (FXPOI) and fragile X-associated tremor/ataxia syndrome (FXTAS), which together are referred to as fragile X-associated disorders (FXDs). Collectively, this group comprises the 3 faces of fragile X. Even though the 3 conditions share a common genetic defect, each one is a separate health condition that results in a variety of body function impairments such as motor delay, musculoskeletal issues related to low muscle tone, coordination limitations, ataxia, tremor, undefined muscle aches and pains, and, for FXTAS, a late-onset neurodegeneration. Although each FXD condition may benefit from physical therapy intervention, available evidence as to the efficacy of intervention appropriate to FXDs is lacking. This perspective article will discuss the genetic basis of FMR1 gene dysfunction and describe health conditions related to this mutation, which have a range of expressions within a family. Physical therapy concerns and possible assessment and intervention strategies will be introduced. Understanding the intergenerational effect of the FMR1 mutation with potential life-span expression is a key component to identifying and treating the health conditions related to this specific genetic condition. © 2016 American Physical Therapy Association.

  10. Abscisic acid-regulated protein degradation causes osmotic stress-induced accumulation of branched-chain amino acids in Arabidopsis thaliana.

    Science.gov (United States)

    Huang, Tengfang; Jander, Georg

    2017-10-01

    Whereas proline accumulates through de novo biosynthesis in plants subjected to osmotic stress, leucine, isoleucine, and valine accumulation in drought-stressed Arabidopsis thaliana is caused by abscisic acid-regulated protein degradation. In response to several kinds of abiotic stress, plants greatly increase their accumulation of free amino acids. Although stress-induced proline increases have been studied the most extensively, the fold-increase of other amino acids, in particular branched-chain amino acids (BCAAs; leucine, isoleucine, and valine), is often higher than that of proline. In Arabidopsis thaliana (Arabidopsis), BCAAs accumulate in response to drought, salt, mannitol, polyethylene glycol, herbicide treatment, and nitrogen starvation. Plants that are deficient in abscisic acid signaling accumulate lower amounts of BCAAs, but not proline and most other amino acids. Previous bioinformatic studies had suggested that amino acid synthesis, rather than protein degradation, is responsible for the observed BCAA increase in osmotically stressed Arabidopsis. However, whereas treatment with the protease inhibitor MG132 decreased drought-induced BCAA accumulation, inhibition of BCAA biosynthesis with the acetolactate synthase inhibitors chlorsulfuron and imazapyr did not. Additionally, overexpression of BRANCHED-CHAIN AMINO ACID TRANSFERASE2 (BCAT2), which is upregulated in response to osmotic stress and functions in BCAA degradation, decreased drought-induced BCAA accumulation. Together, these results demonstrate that BCAA accumulation in osmotically stressed Arabidopsis is primarily the result of protein degradation. After relief of the osmotic stress, BCAA homeostasis is restored over time by amino acid degradation involving BCAT2. Thus, drought-induced BCAA accumulation is different from that of proline, which is accumulated due to de novo synthesis in an abscisic acid-independent manner and remains elevated for a more prolonged period of time after removal of

  11. Magnetic resonance studies on the brain edema by the administration of the osmotic agents

    International Nuclear Information System (INIS)

    Niino, Masaki; Asakura, Tetsuhiko; Nakamura, Katsumi; Yatsushiro, Kazutaka; Kadota, Koki; Sasahira, Masahiro; Fujimoto, Toshiro; Shimooki, Susumu.

    1990-01-01

    Changes of proton relaxation times (T 1 and T 2 ) and MR imaging of the brain edema by the administration of the osmotic agents (mannitol or glycerol) were studied. Subjects were 11 patients who were composed of 4 gliomas, 2 metastatic brain tumors, 2 meningiomas, 2 hypertensive intracerebral hematomas, and a C-P angle tumor. 20% mannitol or 10% glycerol 550 ml was rapidly injected intravenously. Scanning was done before injection, just after injection, and post injection until 2 hours with passing times. We regarded the peritumoral or perihemorrahgical low density area on the CT scan as the edema, and then, relaxation times of the edema was obtained from the ROI of the calculated images corresponding to the surrounding low density area on the CT scan. The results were as follows. 1) In general, relaxation times of the edema showed a tendency to decrease after injection of the osmotic agents. Normal white matter, in the same way, showed the decreasing tendency, but the degree of the decreasing was more clearly in the edematous areas than in the white matter. 2) The changes of relaxation times did not show a uniform pattern. In most cases, relaxation times decreased just after injection. But in a few cases, relaxation times increased just after injection, transiently. In some cases, decreased relaxation times continued more than 2 hours, in the other cases, relaxation times increased at 2 hours. 3) The changes of relaxation times thought to be varied by some factors, that is --kinds of the lesions causing edema, degree of malignancy of the lesions, or phase of edema (acute or chronic) etc. 4) Osmotic agents were supposed to dehydrate the edematous lesions. In the current MR systems, there are considerably large standard deviations and inequality in the magnetic field, therefore, further investigations should be done moreover. (author)

  12. Osmotic effects of polyethylene glycol.

    Science.gov (United States)

    Schiller, L R; Emmett, M; Santa Ana, C A; Fordtran, J S

    1988-04-01

    Polyethylene glycol (PEG) has been used to increase the osmotic pressure of fluids used to cleanse the gastrointestinal tract. However, little is known about its osmotic activity. To investigate this activity systematically, solutions of PEG of differing molecular weights were made and subjected to measurement of osmolality by both freezing point depression and vapor pressure osmometry. Measured osmolality was increasingly greater than predicted from average molecular weight as PEG concentration increased. Measurement of sodium activity in NaCl/PEG solutions by means of an ion-selective electrode suggested that the higher than expected osmolality could be due in part to interactions that, in effect, sequestered water from the solution. Osmolality was consistently greater by freezing point osmometry than by vapor pressure osmometry. To determine which osmometry method reflected biologically relevant osmolality, normal subjects underwent steady-state total gut perfusion with an electrolyte solution containing 105 g/L of PEG 3350. This produced rectal effluent that was hypertonic by freezing point osmometry but isotonic by vapor pressure osmometry. Assuming that luminal fluid reaches osmotic equilibrium with plasma during total gut perfusion, this result suggests that the vapor pressure osmometer accurately reflects the biologically relevant osmolality of intestinal contents. We conclude that PEG exerts more of an osmotic effect than would be predicted from its molecular weight. This phenomenon may reflect interactions between PEG and water molecules that alter the physical chemistry of the solution and sequester water from the solution.

  13. Osmotic homeostasis and NKLy lymphoma cells radiosensitivity

    International Nuclear Information System (INIS)

    Tishchenko, V.V.; Magda, I.N.

    1992-01-01

    In experiments with cells of ascites NKLy lymphoma differing in ploidy and position in the cell cycle, a study was made of the radiosensitivity, osmotic homeostasis peculiarities and thermoradiation changes in potassium content. It was shown that the resistance of osmotic homeostasis of NKLy cells to thermoradiation correlated with their radioresistance

  14. Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS) Motor Dysfunction Modeled in Mice.

    Science.gov (United States)

    Foote, Molly; Arque, Gloria; Berman, Robert F; Santos, Mónica

    2016-10-01

    Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder that affects some carriers of the fragile X premutation (PM). In PM carriers, there is a moderate expansion of a CGG trinucleotide sequence (55-200 repeats) in the fragile X gene (FMR1) leading to increased FMR1 mRNA and small to moderate decreases in the fragile X mental retardation protein (FMRP) expression. The key symptoms of FXTAS include cerebellar gait ataxia, kinetic tremor, sensorimotor deficits, neuropsychiatric changes, and dementia. While the specific trigger(s) that causes PM carriers to progress to FXTAS pathogenesis remains elusive, the use of animal models has shed light on the underlying neurobiology of the altered pathways involved in disease development. In this review, we examine the current use of mouse models to study PM and FXTAS, focusing on recent advances in the field. Specifically, we will discuss the construct, face, and predictive validities of these PM mouse models, the insights into the underlying disease mechanisms, and potential treatments.

  15. Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) Motor Dysfunction Modeled in Mice

    Science.gov (United States)

    Foote, Molly; Arque, Gloria; Berman, Robert F.; Santos, Mónica

    2016-01-01

    Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late onset neurodegenerative disorder that affects some carriers of the Fragile X premutation (PM). In PM carriers there is a moderate expansion of a CGG trinucleotide sequence (55-200 repeats) in the fragile X gene (FMR1) leading to increased FMR1 mRNA and small to moderate decreases in the Fragile X Mental Retardation Protein (FMRP) expression. The key symptoms of FXTAS include cerebellar gait ataxia, kinetic tremor, sensorimotor deficits, neuropsychiatric changes, and dementia. While the specific trigger(s) that cause PM carriers to progress to FXTAS pathogenesis remains elusive, the use of animal models has shed light on the underlying neurobiology of the altered pathways involved in disease development. In this review, we examine the current use of mouse models to study PM and FXTAS, focusing on recent advances in the field. Specifically we will discuss the construct, face and predictive validities of these PM mouse models, the insights into the underlying disease mechanisms and potential treatments. PMID:27255703

  16. Repeat-mediated genetic and epigenetic changes at the FMR1 locus in the Fragile X-related disorders

    Science.gov (United States)

    Usdin, Karen; Hayward, Bruce E.; Kumari, Daman; Lokanga, Rachel A.; Sciascia, Nicholas; Zhao, Xiao-Nan

    2014-01-01

    The Fragile X-related disorders are a group of genetic conditions that include the neurodegenerative disorder, Fragile X-associated tremor/ataxia syndrome (FXTAS), the fertility disorder, Fragile X-associated primary ovarian insufficiency (FXPOI) and the intellectual disability, Fragile X syndrome (FXS). The pathology in all these diseases is related to the number of CGG/CCG-repeats in the 5′ UTR of the Fragile X mental retardation 1 (FMR1) gene. The repeats are prone to continuous expansion and the increase in repeat number has paradoxical effects on gene expression increasing transcription on mid-sized alleles and decreasing it on longer ones. In some cases the repeats can simultaneously both increase FMR1 mRNA production and decrease the levels of the FMR1 gene product, Fragile X mental retardation 1 protein (FMRP). Since FXTAS and FXPOI result from the deleterious consequences of the expression of elevated levels of FMR1 mRNA and FXS is caused by an FMRP deficiency, the clinical picture is turning out to be more complex than once appreciated. Added complications result from the fact that increasing repeat numbers make the alleles somatically unstable. Thus many individuals have a complex mixture of different sized alleles in different cells. Furthermore, it has become apparent that the eponymous fragile site, once thought to be no more than a useful diagnostic criterion, may have clinical consequences for females who inherit chromosomes that express this site. This review will cover what is currently known about the mechanisms responsible for repeat instability, for the repeat-mediated epigenetic changes that affect expression of the FMR1 gene, and for chromosome fragility. It will also touch on what current and future options are for ameliorating some of these effects. PMID:25101111

  17. Increased Resistance to osmotic lysis of sickled erythrocytes ...

    African Journals Online (AJOL)

    treated with CNw had significantly reduced osmotic lysis when compared with the untreated set (P<0.05, respectively) at various hypotonic NaCl concentrations. Various Hb genotypes exhibited a graded increase in osmotic pressure lysis in ...

  18. Currency crisis and external fragility: a Minskyan interpretation applied to the Brazilian economy between 1999 and 2013

    Directory of Open Access Journals (Sweden)

    Victor Hugo Rocha Sarto

    2016-12-01

    Full Text Available This work has two goals. The first one is to develop an interpretation for open economies founded on Minsky’s financial fragility hypothesis about the process of a currency crisis and its determinants. The deterioration of an economy’s external financial structure is identified as the reason for the increase of its crisis susceptibility. With this approach, we create external fragility indexes intending to measure an economy’s crisis susceptibility. Our second objective is to evaluate the Brazilian external fragility between 1999 and 2013 using the index and the interpretation previously developed. The results suggest that Brazilian’s external fragility suffered a gradual and significant decrease and tends to follow stable trend in the coming years.

  19. Structure and osmotic pressure of ionic microgel dispersions

    Energy Technology Data Exchange (ETDEWEB)

    Hedrick, Mary M. [Department of Physics, North Dakota State University, Fargo, North Dakota 58108-6050 (United States); Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108-6050 (United States); Chung, Jun Kyung; Denton, Alan R., E-mail: alan.denton@ndsu.edu [Department of Physics, North Dakota State University, Fargo, North Dakota 58108-6050 (United States)

    2015-01-21

    We investigate structural and thermodynamic properties of aqueous dispersions of ionic microgels—soft colloidal gel particles that exhibit unusual phase behavior. Starting from a coarse-grained model of microgel macroions as charged spheres that are permeable to microions, we perform simulations and theoretical calculations using two complementary implementations of Poisson-Boltzmann (PB) theory. Within a one-component model, based on a linear-screening approximation for effective electrostatic pair interactions, we perform molecular dynamics simulations to compute macroion-macroion radial distribution functions, static structure factors, and macroion contributions to the osmotic pressure. For the same model, using a variational approximation for the free energy, we compute both macroion and microion contributions to the osmotic pressure. Within a spherical cell model, which neglects macroion correlations, we solve the nonlinear PB equation to compute microion distributions and osmotic pressures. By comparing the one-component and cell model implementations of PB theory, we demonstrate that the linear-screening approximation is valid for moderately charged microgels. By further comparing cell model predictions with simulation data for osmotic pressure, we chart the cell model’s limits in predicting osmotic pressures of salty dispersions.

  20. Structure and osmotic pressure of ionic microgel dispersions

    International Nuclear Information System (INIS)

    Hedrick, Mary M.; Chung, Jun Kyung; Denton, Alan R.

    2015-01-01

    We investigate structural and thermodynamic properties of aqueous dispersions of ionic microgels—soft colloidal gel particles that exhibit unusual phase behavior. Starting from a coarse-grained model of microgel macroions as charged spheres that are permeable to microions, we perform simulations and theoretical calculations using two complementary implementations of Poisson-Boltzmann (PB) theory. Within a one-component model, based on a linear-screening approximation for effective electrostatic pair interactions, we perform molecular dynamics simulations to compute macroion-macroion radial distribution functions, static structure factors, and macroion contributions to the osmotic pressure. For the same model, using a variational approximation for the free energy, we compute both macroion and microion contributions to the osmotic pressure. Within a spherical cell model, which neglects macroion correlations, we solve the nonlinear PB equation to compute microion distributions and osmotic pressures. By comparing the one-component and cell model implementations of PB theory, we demonstrate that the linear-screening approximation is valid for moderately charged microgels. By further comparing cell model predictions with simulation data for osmotic pressure, we chart the cell model’s limits in predicting osmotic pressures of salty dispersions

  1. Red blood cell phosphate concentration and osmotic resistance during dietary phosphate depletion in dairy cows

    NARCIS (Netherlands)

    Grünberg, W; Mol, J A; Teske, E

    BACKGROUND: Hypophosphatemia in early lactating dairy cows has been implicated as primary cause for postparturient hemoglobinuria in cattle. Decreased availability of phosphorus has been proposed to reduce adenosine triphosphate synthesis of erythrocytes and thereby reduce osmotic resistance of

  2. Effect of drought and abscisic acid application on the osmotic adjustment of four wheat cultivars

    International Nuclear Information System (INIS)

    Iqbal, S.; Bano, A.

    2010-01-01

    The accumulation of osmolytes in leaf tissues and the abscisic acid-induced stomatal closure are well-recognized mechanisms associated with drought tolerance in crop plants. We determine the response in terms of osmotic potential and the contents of leaf proline, glycine betaine and soluble sugar at booting and grain filling stages of four wheat (Triticum aestivum L.) cultivars to drought and exogenously applied abscisic acid (ABA) in a pot study. Leaf sample were collected 3, 6 and 9 days after drought induction and at 48 and 72 h of re-watering (recovery). Marked decreases in osmotic potential associated with the accumulation of proline, glycine betaine and soluble sugars occurred under conditions of drought stress Accession 011320 was most sensitive to drought and showed the largest decrease in osmotic potential and least accumulation of proline, sugar and glycine betaine The inhibitory effects of drought stress were ameliorated by exogenous application of ABA. This ameliorating effect was more pronounced at the booting than at grain filling stage particularly in the sensitive accession 011320. Upon rewatering the recovery from drought stress was found to be greater in case of abscisic acid application. The leaf praline content is seen to be a suitable indicator for selecting drought-tolerant genotypes. (author)

  3. Enhanced monoclonal antibody production by gradual increase of osmotic pressure

    OpenAIRE

    Lin, Jianqiang; Takagi, Mutsumi; Qu, Yinbo; Gao, Peiji; Yoshida, Toshiomi

    1999-01-01

    The time length required for the adaptation of AFP-27 hybridoma cells to high osmotic pressure and the effect of a gradual increase of osmotic pressure on monoclonal antibody production were investigated. When the cells were subjected to an increase of osmotic pressure from 300 mOsmol kg-1 to 366 mOsmol kg- 1, the intracellular content of osmoprotective free amino acids reached a maximum level 6 h after the osmotic pressure was increased to 366 mOsmol kg-1. The same time period of 6 h incubat...

  4. Photosystem I shows a higher tolerance to sorbitol-induced osmotic stress than photosystem II in the intertidal macro-algae Ulva prolifera (Chlorophyta).

    Science.gov (United States)

    Gao, Shan; Zheng, Zhenbing; Gu, Wenhui; Xie, Xiujun; Huan, Li; Pan, Guanghua; Wang, Guangce

    2014-10-01

    The photosynthetic performance of the desiccation-tolerant, intertidal macro-algae Ulva prolifera was significantly affected by sorbitol-induced osmotic stress. Our results showed that photosynthetic activity decreased significantly with increases in sorbitol concentration. Although the partial activity of both photosystem I (PS I) and photosystem II (PS II) was able to recover after 30 min of rehydration, the activity of PS II decreased more rapidly than PS I. At 4 M sorbitol concentration, the activity of PS II was almost 0 while that of PS I was still at about one third of normal levels. Following prolonged treatment with 1 and 2 M sorbitol, the activity of PS I and PS II decreased slowly, suggesting that the effects of moderate concentrations of sorbitol on PS I and PS II were gradual. Interestingly, an increase in non-photochemical quenching occurred under these conditions in response to moderate osmotic stress, whereas it declined significantly under severe osmotic stress. These results suggest that photoprotection in U. prolifera could also be induced by moderate osmotic stress. In addition, the oxidation of PS I was significantly affected by osmotic stress. P700(+) in the thalli treated with high concentrations of sorbitol could still be reduced, as PS II was inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), but it could not be fully oxidized. This observation may be caused by the higher quantum yield of non-photochemical energy dissipation in PS I due to acceptor-side limitation (Y(NA)) during rehydration in seawater containing DCMU. © 2014 Scandinavian Plant Physiology Society.

  5. Dissociation of social and nonsocial anxiety in a mouse model of fragile X syndrome

    OpenAIRE

    Liu, Zhong-Hua; Smith, Carolyn Beebe

    2009-01-01

    Anxiety is a common symptom in fragile X patients. However, an anxiety-prone phenotype in mouse models of fragile X syndrome is not clear. In most studies of fmr1 knockout mice, decreased anxiety-like responses in exploratory-based models are found, but mice also exhibit abnormal social interactions. We hypothesize the coexistence of elevated social anxiety and reduced nonsocial anxiety in fmr1 knockout mice. In the present study, we applied an automated three-chambered social approach method...

  6. Flooding Fragility Experiments and Prediction

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Curtis L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Tahhan, Antonio [Idaho National Lab. (INL), Idaho Falls, ID (United States); Muchmore, Cody [Idaho National Lab. (INL), Idaho Falls, ID (United States); Nichols, Larinda [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bhandari, Bishwo [Idaho National Lab. (INL), Idaho Falls, ID (United States); Pope, Chad [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    This report describes the work that has been performed on flooding fragility, both the experimental tests being carried out and the probabilistic fragility predictive models being produced in order to use the text results. Flooding experiments involving full-scale doors have commenced in the Portal Evaluation Tank. The goal of these experiments is to develop a full-scale component flooding experiment protocol and to acquire data that can be used to create Bayesian regression models representing the fragility of these components. This work is in support of the Risk-Informed Safety Margin Characterization (RISMC) Pathway external hazards evaluation research and development.

  7. Plant response to sunflower seeds to osmotic conditioning

    Directory of Open Access Journals (Sweden)

    Camila Santos Barros de Morais

    2014-10-01

    Full Text Available The aim of this study was to evaluate the effect of seeds osmotic conditioning in seedlings emergence and plants performance of sunflower. Three lots of seeds sunflower (Catissol, was submited to osmotic conditioning with polyethylene glycol solution, –2,0 MPa in aerated system, under 15 ºC for 8 hour and then was evaluated for germination tests and vigour. Under filed conditions was conducted emergency evaluations of seedling, plants development as well as the productivity and seeds quality, and the accumulation of nutrients in the seeds. The osmotic conditioning improve the survival of seedling, the dry matter mass to aerial part of plants from 60 days after sowing and oil content, in lots with low seeds physiological quality. The osmotic conditioning not increase the seeds yield but promotes the vigour of seeds produced, regardless of the lot used for sowing seeds.

  8. New Osmosis Law and Theory: the New Formula that Replaces van't Hoff Osmotic Pressure Equation

    OpenAIRE

    Huang, Hung-Chung; Xie, Rongqing

    2012-01-01

    This article derived a new abstract concept from the osmotic process and concluded it via "osmotic force" with a new law -- "osmotic law". The "osmotic law" describes that, in an osmotic system, osmolyte moves osmotically from the side with higher "osmotic force" to the side with lower "osmotic force". In addition, it was proved mathematically that the osmotic process could be explained perfectly via "osmotic force" and "osmotic laws", which can prevent the difficulties in using current "osmo...

  9. Fragile X-associated disorders: Don't miss them.

    Science.gov (United States)

    Birch, Rachael C; Cohen, Jonathan; Trollor, Julian N

    2017-01-01

    Fragile X-associated disorders are a family of inherited disorders caused by expansions in the Fragile X Mental Retardation 1 (FMR1) gene. Premutation expansions of the FMR1 gene confer risk for fragile X-associated primary ovarian insufficiency and fragile X-associated tremor ataxia syndrome, as well as other medical and psychiatric comorbidities. Premutation expansions of the FMR1 gene are common in the general population. However, fragile X-associated disorders are frequently under-recognised and often misdiagnosed. The aim of this article is to describe fragile X-associated disorders and identify specific considerations for general practitioners (GPs) during identification and management of these disorders. GPs have a critical role in the identification of fragile X-associated disorders, as well as coordination of complex care needs. Prompt recognition and appropriate management of these disorders and potential medical and psychiatric comorbidities will have important implications not only for the affected patient, but also other family members who may be at risk.

  10. Component fragilities - data collection, analysis and interpretation

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.

    1986-01-01

    As part of the component fragility research program sponsored by the US Nuclear Regulatory Commission, BNL is involved in establishing seismic fragility levels for various nuclear power plant equipment with emphasis on electrical equipment, by identifying, collecting and analyzing existing test data from various sources. BNL has reviewed approximately seventy test reports to collect fragility or high level test data for switchgears, motor control centers and similar electrical cabinets, valve actuators and numerous electrical and control devices of various manufacturers and models. Through a cooperative agreement, BNL has also obtained test data from EPRI/ANCO. An analysis of the collected data reveals that fragility levels can best be described by a group of curves corresponding to various failure modes. The lower bound curve indicates the initiation of malfunctioning or structural damage, whereas the upper bound curve corresponds to overall failure of the equipment based on known failure modes occurring separately or interactively. For some components, the upper and lower bound fragility levels are observed to vary appreciably depending upon the manufacturers and models. An extensive amount of additional fragility or high level test data exists. If completely collected and properly analyzed, the entire data bank is expected to greatly reduce the need for additional testing to establish fragility levels for most equipment

  11. Optimisation of ultrasound-assisted osmotic dehydration of sweet potato (Ipomea batatas) using response surface methodology.

    Science.gov (United States)

    Oladejo, Ayobami Olayemi; Ma, Haile

    2016-08-01

    Sweet potato is a highly nutritious tuber crop that is rich in β-carotene. Osmotic dehydration is a pretreatment method for drying of fruit and vegetables. Recently, ultrasound technology has been applied in food processing because of its numerous advantages which include time saving, little damage to the quality of the food. Thus, there is need to investigate and optimise the process parameters [frequency (20-50 kHz), time (10-30 min) and sucrose concentration (20-60% w/v)] for ultrasound-assisted osmotic dehydration of sweet potato using response surface methodology. The optimised values obtained were frequency of 33.93 kHz, time of 30 min and sucrose concentration of 35.69% (w/v) to give predicted values of 21.62, 4.40 and 17.23% for water loss, solid gain and weight reduction, respectively. The water loss and weight reduction increased when the ultrasound frequency increased from 20 to 35 kHz and then decreased as the frequency increased from 35 to 50 kHz. The results from this work show that low ultrasound frequency favours the osmotic dehydration of sweet potato and also reduces the use of raw material (sucrose) needed for the osmotic dehydration of sweet potato. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  12. Component fragility research program

    International Nuclear Information System (INIS)

    Tsai, N.C.; Mochizuki, G.L.; Holman, G.S.

    1989-11-01

    To demonstrate how ''high-level'' qualification test data can be used to estimate the ultimate seismic capacity of nuclear power plant equipment, we assessed in detail various electrical components tested by the Pacific Gas ampersand Electric Company for its Diablo Canyon plant. As part of our Phase I Component Fragility Research Program, we evaluated seismic fragility for five Diablo Canyon components: medium-voltage (4kV) switchgear; safeguard relay board; emergency light battery pack; potential transformer; and station battery and racks. This report discusses our Phase II fragility evaluation of a single Westinghouse Type W motor control center column, a fan cooler motor controller, and three local starters at the Diablo Canyon nuclear power plant. These components were seismically qualified by means of biaxial random motion tests on a shaker table, and the test response spectra formed the basis for the estimate of the seismic capacity of the components. The seismic capacity of each component is referenced to the zero period acceleration (ZPA) and, in our Phase II study only, to the average spectral acceleration (ASA) of the motion at its base. For the motor control center, the seismic capacity was compared to the capacity of a Westinghouse Five-Star MCC subjected to actual fragility tests by LLNL during the Phase I Component Fragility Research Program, and to generic capacities developed by the Brookhaven National Laboratory for motor control center. Except for the medium-voltage switchgear, all of the components considered in both our Phase I and Phase II evaluations were qualified in their standard commercial configurations or with only relatively minor modifications such as top bracing of cabinets. 8 refs., 67 figs., 7 tabs

  13. Mass transfer kinetics during osmotic dehydration of pomegranate arils.

    Science.gov (United States)

    Mundada, Manoj; Hathan, Bahadur Singh; Maske, Swati

    2011-01-01

    The mass transfer kinetics during osmotic dehydration of pomegranate arils in osmotic solution of sucrose was studied to increase palatability and shelf life of arils. The freezing of the whole pomegranate at -18 °C was carried out prior to osmotic dehydration to increase the permeability of the outer cellular layer of the arils. The osmotic solution concentrations used were 40, 50, 60°Bx, osmotic solution temperatures were 35, 45, 55 °C. The fruit to solution ratio was kept 1:4 (w/w) during all the experiments and the process duration varied from 0 to 240 min. Azuara model and Peleg model were the best fitted as compared to other models for water loss and solute gain of pomegranate arils, respectively. Generalized Exponential Model had an excellent fit for water loss ratio and solute gain ratio of pomegranate arils. Effective moisture diffusivity of water as well as solute was estimated using the analytical solution of Fick's law of diffusion. For above conditions of osmotic dehydration, average effective diffusivity of water loss and solute gain varied from 2.718 × 10(-10) to 5.124 × 10(-10) m(2)/s and 1.471 × 10(-10) to 5.147 × 10(-10) m(2)/s, respectively. The final product was successfully utilized in some nutritional formulations such as ice cream and bakery products.

  14. Osmotic stress alters the balance between organic and inorganic solutes in flax (Linum usitatissimum).

    Science.gov (United States)

    Quéro, Anthony; Molinié, Roland; Elboutachfaiti, Redouan; Petit, Emmanuel; Pau-Roblot, Corinne; Guillot, Xavier; Mesnard, François; Courtois, Josiane

    2014-01-01

    Flax (Linum usitatissimum) is grown for its oil and its fiber. This crop, cultivated in temperate regions, has seen a renewed interest due to the presence of abundant molecules of interest for many applications. Little information is available about the behavior of flax during osmotic stress; yet this is considered a major stress that causes significant yield losses in most crops. To control the presence of this stress better, flax behavior was investigated following the application of osmotic stress and the response was examined by applying increasing concentrations of PEG 8000. This resulted in the reorganization of 32 metabolites and 6 mineral ions in the leaves. The analysis of these two types of solute highlighted the contrasting behavior between a higher metabolite content (particularly fructose, glucose and proline) and a decrease in mineral ions (especially nitrate and potassium) following PEG treatment. However, this reorganization did not lead to a greater accumulation of solutes, with the total amount remaining unchanged in leaves during osmotic stress. Copyright © 2013 Elsevier GmbH. All rights reserved.

  15. Silicon alleviates salt and drought stress of Glycyrrhiza uralensis seedling by altering antioxidant metabolism and osmotic adjustment.

    Science.gov (United States)

    Zhang, Wenjin; Xie, Zhicai; Wang, Lianhong; Li, Ming; Lang, Duoyong; Zhang, Xinhui

    2017-05-01

    This study was conducted to determine effect and mechanism of exogenous silicon (Si) on salt and drought tolerance of Glycyrrhiza uralensis seedling by focusing on the pathways of antioxidant defense and osmotic adjustment. Seedling growth, lipid peroxidation, antioxidant metabolism, osmolytes concentration and Si content of G. uralensis seedlings were analyzed under control, salt and drought stress [100 mM NaCl with 0, 10 and 20% of PEG-6000 (Polyethylene glycol-6000)] with or without 1 mM Si. Si addition markedly affected the G. uralensis growth in a combined dose of NaCl and PEG dependent manner. In brief, Si addition improved germination rate, germination index, seedling vitality index and biomass under control and NaCl; Si also increased radicle length under control, NaCl and NaCl-10% PEG, decreased radicle length, seedling vitality index and germination parameters under NaCl-20% PEG. The salt and drought stress-induced-oxidative stress was modulated by Si application. Generally, Si application increased catalase (CAT) activity under control and NaCl-10% PEG, ascorbate peroxidase (APX) activity under all treatments and glutathione (GSH) content under salt combined drought stress as compared with non-Si treatments, which resisted to the increase of superoxide radicals and hydrogen peroxide caused by salt and drought stress and further decreased membrane permeability and malondialdehyde (MDA) concentration. Si application also increased proline concentration under NaCl and NaCl-20% PEG, but decreased it under NaCl-10% PEG, indicating proline play an important role in G. uralensis seedling response to osmotic stress. In conclusion, Si could ameliorate adverse effects of salt and drought stress on G. uralensis likely by reducing oxidative stress and osmotic stress, and the oxidative stress was regulated through enhancing of antioxidants (mainly CAT, APX and GSH) and osmotic stress was regulated by proline.

  16. Efficiency of Osmotic Dehydration of Apples in Polyols Solutions.

    Science.gov (United States)

    Cichowska, Joanna; Żubernik, Joanna; Czyżewski, Jakub; Kowalska, Hanna; Witrowa-Rajchert, Dorota

    2018-02-17

    The present study aimed to evaluate the influence of selected compounds from the polyol group, as well as other saccharides, on the osmotic dehydration process of apples. The following alternative solutions were examined: erythritol, xylitol, maltitol, inulin and oligofructose. Efficiency of the osmotic dehydration process was evaluated based on the kinetics of the process, and through comparison of the results obtained during the application of a sucrose solution. This innovative research utilizes alternative solutions in osmotic pretreatment, which until now, have not been commonly used in fruit processing by researchers worldwide. Results indicate that erythritol and xylitol show stronger or similar efficiency to sucrose; however, the use of inulin, as well as oligofructose, was not satisfactory due to the insufficient, small osmotic driving forces of the process, and the low values of mass transfer parameters.

  17. Inverse osmotic process for radioactive laundry waste

    Energy Technology Data Exchange (ETDEWEB)

    Ebara, K; Takahashi, S; Sugimoto, Y; Yusa, H; Hyakutake, H

    1977-01-07

    Purpose: To effectively recover the processing amount reduced in a continuous treatment. Method: Laundry waste containing radioactive substances discharged from a nuclear power plant is processed in an inverse osmotic process while adding starch digesting enzymes such as amylase and takadiastase, as well as soft spherical bodies such as sponge balls of a particle diameter capable of flowing in the flow of the liquid wastes along the inverse osmotic membrane pipe and having such a softness and roundness as not to damage the inverse osmotic membrane. This process can remove the floating materials such as thread dusts or hairs deposited on the membrane surface by the action of the soft elastic balls and remove paste or the like through decomposition by the digesting enzymes. Consequently, effective recovery can be attained for the reduced processing amount.

  18. Osmotic stress tolerance in semi-terrestrial tardigrades

    DEFF Research Database (Denmark)

    Heidemann, Nanna W T; Smith, Daniel K.; Hygum, Thomas L.

    2016-01-01

    Little is known about ionic and osmotic stress tolerance in tardigrades. Here, we examine salt stress tolerance in Ramazzottius oberhaeuseri and Echiniscus testudo from Nivå (Denmark) and address whether limno-terrestrial tardigrades can enter a state of quiescence (osmobiosis) in the face of high......-ionic osmolytes as compared to NaCl. Ramazzottius oberhaeuseri furthermore readily regained activity following gradual increases in non-ionic osmolytes and NaCl of up to 2434 ± 28 and 1905 ± 3 mOsm kg−1, respectively, showing that short-term acclimation promoted salt stress tolerance. Our results suggest...... that the limno-terrestrial R. oberhaeuseri enters a state of quiescence in the face of high external osmotic pressure and that it, in this state, is highly tolerant of ionic and osmotic stress....

  19. Seismic component fragility data base for IPEEE

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.; Hofmayer, C.

    1990-01-01

    Seismic probabilistic risk assessment or a seismic margin study will require a reliable data base of seismic fragility of various equipment classes. Brookhaven National Laboratory (BNL) has selected a group of equipment and generically evaluated the seismic fragility of each equipment class by use of existing test data. This paper briefly discusses the evaluation methodology and the fragility results. The fragility analysis results when used in the Individual Plant Examination for External Events (IPEEE) Program for nuclear power plants are expected to provide insights into seismic vulnerabilities of equipment for earthquakes beyond the design basis. 3 refs., 1 fig., 1 tab

  20. MUS81 promotes common fragile site expression

    DEFF Research Database (Denmark)

    Ying, Songmin; Minocherhomji, Sheroy; Chan, Kok Lung

    2013-01-01

    Fragile sites are chromosomal loci with a propensity to form gaps or breaks during early mitosis, and their instability is implicated as being causative in certain neurological disorders and cancers. Recent work has demonstrated that the so-called common fragile sites (CFSs) often impair the fait......Fragile sites are chromosomal loci with a propensity to form gaps or breaks during early mitosis, and their instability is implicated as being causative in certain neurological disorders and cancers. Recent work has demonstrated that the so-called common fragile sites (CFSs) often impair...... the faithful disjunction of sister chromatids in mitosis. However, the mechanisms by which CFSs express their fragility, and the cellular factors required to suppress CFS instability, remain largely undefined. Here, we report that the DNA structure-specific nuclease MUS81-EME1 localizes to CFS loci in early...

  1. Calcium and Calmodulin Are Involved in Nitric Oxide-Induced Adventitious Rooting of Cucumber under Simulated Osmotic Stress.

    Science.gov (United States)

    Niu, Lijuan; Yu, Jian; Liao, Weibiao; Yu, Jihua; Zhang, Meiling; Dawuda, Mohammed M

    2017-01-01

    Osmotic stress is a major form of abiotic stress that adversely affects growth and development of plants and subsequently reduces yield and quality of crops. In this study, the effect of nitric oxide (NO) and calcium (Ca 2+ ) on the process of adventitious rooting in cucumber ( Cucumis sativus L.) under simulated osmotic stress was investigated. The results revealed that the effect of exogenous NO and Ca 2+ in promoting the development of adventitious roots in cucumber seedlings under simulated osmotic stress was dose-dependent, with a maximal biological response at 10 μM NO donor nitroprusside (SNP) or 200 μM Ca 2+ . The application of Ca 2+ chelators or channel inhibitors and calmodulin (CaM) antagonists significantly reversed NO-induced adventitious rooting, implying that endogenous Ca 2+ /CaM might be involved in NO-induced adventitious rooting under osmotic stress. Moreover, intracellular Ca amount was also increased by NO in cucumber hypocotyls during the development of adventitious roots under osmotic stress. This increase of endogenous Ca 2+ was inhibited by NO specific scavenger 2-(4-carboxyphenyl) -4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt (cPTIO), nitrate reductase inhibitors tungstate (Na 2 WO 4 ) and sodium azide (NaN 3 ) . This gives an indication that Ca 2+ might be a downstream signaling molecule in the adventitious root development by NO under osmotic condition. The results also show that NO or Ca 2+ play a positive role in improving plant water status and photosynthetic system by increasing chlorophyll content and photochemical activity in leaves. Furthermore, NO and Ca 2+ treatment might alleviate the negative effects of osmotic stress by decreasing membrane damage and reactive oxygen species (ROS) production by enhancing the activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). Therefore, Ca 2+ /CaM may act as a downstream signaling molecule in NO-induced development of adventitious root

  2. Effect of salinity on hemolymph osmotic pressure, sodium concentration and Na+-K+-ATPase activity of gill of Chinese crab, Eriocheir sinensis

    Science.gov (United States)

    Liu, Hongyu; Pan, Luqing; Fu, Lü

    2008-02-01

    The effects of salinity on hemolymph osmotic pressure, Na+ concentration and Na+-K+-ATPase activity of gill of Chinese crab Eriocheir sinensis were studied. The results showed that hemolymph osmotic pressure and Na+ concentration increased significantly ( P0.05); However, the protein concentration decreased gradually with the increase of salinity from 0.25 d to 1 d, and then tended to be stable from day 1 to day 15.

  3. MORPHOMETRIC PARAMETERS AND MICRORELIEF OF THE LUMBRICUS CELOMOCYTES IN THE CONDITIONS OF THE OSMOTIC PRESSURE

    Directory of Open Access Journals (Sweden)

    Andrey Andreevich Prisnyi

    2017-10-01

    Full Text Available Background: Study the morphometric parameters and microrelief of the coelomocytes membrane of the Lumbricus representatives in normal and under osmotic pressure. Materials and methods: In the experiments, representatives of three species belonging to the genus Lumbricus were used. To conduct each series of experiments a coelomic liquid of 15 representatives of each species was used. From the circulation system of each individual examined, at least 250 cells were processed. The study of morphometric parameters of coelomocytes was carried out in isotonic conditions, and also with the use of osmotic tests in vitro. The features of the surface topography of coelomocytes were study using the “Integra Vita Probe Nanaboratorium” (NT-MDT, Russia. The analysis of amplitude and functional average statistical parameters of membrane roughness is carried out. The results of the research were processed using statistics methods using the Microsoft Excel 7.0 analysis package. Results: The Lumbricus representatives of revealed differences in the responses of amoebocytes and eleocytes to the effect of osmotic stress. Under the conditions of osmotic pressure, several morphologically different forms were found among the cells of each type. This indicates the potential ability of coelomocytes to spread out on the substrate for any type of osmotic pressure. The change in the topography of the cell membrane of coelomocytes under the hypoosmotic pressure is characterized by a smoothing of the microrelief structures with a decrease in the size of the microvysings and microinvaginations. Conclusion: The microrelief of the coelomocytes membrane reflects the features of their functional status changing under the influence of environmental factors.

  4. Recovery of leaf elongation during short term osmotic stress correlates with osmotic adjustment and cell turgor restoration in different durum wheat cultivars

    International Nuclear Information System (INIS)

    Mahdid, M.

    2014-01-01

    In order to investigate the responses of leaf elongation rate (LER), turgor and osmotic adjustment (OA) during a short-term stress (7 hours) imposed by PEG6000 and a recovery phase, three durum wheat (Triticum durum L.) varieties (Inrat; MBB; and OZ ) were grown in aerated nutrient solutions. Leaf elongation kinetics of leaf 3 was estimated using LVDT. Turgor was estimated using a cell pressure probe; osmotic potential as well as total sugars and potassium (K+) concentrations were estimated from expressed sap of elongation zone. Growth recovered rapidly and then stabilised at a lower value. A significant difference was found in % recovery of LER between the varieties. The cessation of growth after stress coincided with a decrease in turgor followed by a recovery period reaching control values in MBB and Inrat. A strong correlation (R2 = 0.83) between the reduction in turgor (turgor) and % recovery of LER was found at 7 hours after stress. The difference in the partial recovery of LER between varieties was thus related to the capacity of partial turgor recovery. Partial turgor recovery is associated with sugar or K+ based OA which indicates its importance in maintaining high LER values under water deficit. (author)

  5. Fecal osmotic gap and pH in experimental diarrhea of various causes.

    Science.gov (United States)

    Eherer, A J; Fordtran, J S

    1992-08-01

    Although the osmotic gap of fecal fluid is often used to distinguish osmotic diarrhea from secretory diarrhea, there has never been a scientific evaluation of the validity of this concept. Similarly, although a low fecal fluid pH value is used to indicate that diarrhea is mediated by carbohydrate malabsorption, the validity of this method is unproven. Therefore, in the present study, diarrhea was induced in normal subjects by different mechanisms and fecal fluid osmotic gap (using an assumed fecal fluid osmolality of 290 mOsm/kg) and pH were measured. In secretory diarrhea caused by phenolphthalein, the osmotic gap was always less than 50 mOsm/kg, whereas in osmotic diarrhea caused by polyethylene glycol, magnesium hydroxide, lactulose, and sorbitol, the osmotic gap always exceeded 50 mOsm/kg. In osmotic diarrhea caused by sodium sulfate, the fecal fluid osmotic gap was less than 50 mOsm/kg, but phenolphthalein-induced secretory diarrhea could be distinguished from sodium sulfate-induced osmotic diarrhea by the fecal chloride concentration. When diarrhea was caused by carbohydrate malabsorption (lactulose or sorbitol), the fecal fluid pH was always less than 5.6 and usually less than 5.3; by contrast, other causes of diarrhea rarely caused a fecal pH as low as 5.6 and never caused a pH less than 5.3. It is concluded that measurement of fecal fluid osmotic gap and pH can distinguish various mechanisms of experimental diarrhea in normal subjects. The concepts on which these tests are based are therefore verified experimentally.

  6. A Simple Membrane Osmometer System & Experiments that Quantitatively Measure Osmotic Pressure

    Science.gov (United States)

    Marvel, Stephen C.; Kepler, Megan V.

    2009-01-01

    It is important for students to be exposed to the concept of osmotic pressure. Understanding this concept lays the foundation for deeper discussions that lead to more theoretical aspects of water movement associated with the concepts of free energy, water potential, osmotic potential, pressure potential, and osmotic adjustment. The concept of…

  7. Efficiency of Osmotic Dehydration of Apples in Polyols Solutions

    Directory of Open Access Journals (Sweden)

    Joanna Cichowska

    2018-02-01

    Full Text Available The present study aimed to evaluate the influence of selected compounds from the polyol group, as well as other saccharides, on the osmotic dehydration process of apples. The following alternative solutions were examined: erythritol, xylitol, maltitol, inulin and oligofructose. Efficiency of the osmotic dehydration process was evaluated based on the kinetics of the process, and through comparison of the results obtained during the application of a sucrose solution. This innovative research utilizes alternative solutions in osmotic pretreatment, which until now, have not been commonly used in fruit processing by researchers worldwide. Results indicate that erythritol and xylitol show stronger or similar efficiency to sucrose; however, the use of inulin, as well as oligofructose, was not satisfactory due to the insufficient, small osmotic driving forces of the process, and the low values of mass transfer parameters.

  8. Influence of power ultrasound on the main quality properties and cell viability of osmotic dehydrated cranberries.

    Science.gov (United States)

    Nowacka, Malgorzata; Fijalkowska, Aleksandra; Wiktor, Artur; Dadan, Magdalena; Tylewicz, Urszula; Dalla Rosa, Marco; Witrowa-Rajchert, Dorota

    2018-02-01

    The aim of the study was to investigate the effect of ultrasound treatment in two osmotic solutions, carried out at different time, on some physical properties, antioxidant activity and cell survival of cranberries. Ultrasound treatment was conducted at 21kHz for 30 and 60min in liquid medium: 61.5% sucrose solution and 30% sucrose solution with 0.1% steviol glycosides addition. Some samples before the ultrasound treatment were subjected to cutting or blanching. The results showed that dry matter content and concentration of the dissolved substances increased during ultrasound treatment in osmotic solution, however higher value was observed for treatment in 61.5% sucrose solution and for longer time. Water activity and volume of cranberries did not change after the ultrasonic treatment. Combined treatment led to colour and antioxidant activity alterations as well. A cell viability of whole and cut samples decreased after 60min of osmotic treatment and completely lost in the blanched samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Inverse osmotic process for radioactive laundry waste

    International Nuclear Information System (INIS)

    Ebara, Katsuya; Takahashi, Sankichi; Sugimoto, Yoshikazu; Yusa, Hideo; Hyakutake, Hiroshi.

    1977-01-01

    Purpose: To effectively recover the processing amount reduced in a continuous treatment. Method: Laundry waste containing radioactive substances discharged from a nuclear power plant is processed in an inverse osmotic process while adding starch digesting enzymes such as amylase and takadiastase, as well as soft spherical bodies such as sponge balls of a particle diameter capable of flowing in the flow of the liquid wastes along the inverse osmotic membrane pipe and having such a softness and roundness as not to damage the inverse osmotic membrane. This process can remove the floating materials such as thread dusts or hairs deposited on the membrane surface by the action of the soft elastic balls and remove paste or the like through decomposition by the digesting enzymes. Consequently, effective recovery can be attained for the reduced processing amount. (Furukawa, Y.)

  10. Erythrocyte swelling and membrane hole formation in hypotonic media as studied by conductometry.

    Science.gov (United States)

    Pribush, A; Meyerstein, D; Hatskelzon, L; Kozlov, V; Levi, I; Meyerstein, N

    2013-02-01

    Hypoosmotic swelling of erythrocytes and the formation of membrane holes were studied by measuring the dc conductance (G). In accordance with the theoretical predictions, these processes are manifested by a decrease in G followed by its increase. Thus, unlike the conventional osmotic fragility test, the proposed methodological approach allows investigations of both the kinetics of swelling and the erythrocyte fragility. It is shown that the initial rate of swelling and the equilibrium size of the cells are affected by the tonicity of a hypotonic solution and the membrane rheological properties. Because the rupture of biological membranes is a stochastic process, a time-dependent increase in the conductance follows an integral distribution function of the membrane lifetime. The main conclusion which stems from reported results is that information about rheological properties of red blood cell (RBC) membranes and the resistivity of RBCs to a certain osmotic shock may be extracted from conductance signals.

  11. Transcriptome Profiling of Watermelon Root in Response to Short-Term Osmotic Stress.

    Science.gov (United States)

    Yang, Yongchao; Mo, Yanling; Yang, Xiaozheng; Zhang, Haifei; Wang, Yongqi; Li, Hao; Wei, Chunhua; Zhang, Xian

    2016-01-01

    Osmotic stress adversely affects the growth, fruit quality and yield of watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai). Increasing the tolerance of watermelon to osmotic stress caused by factors such as high salt and water deficit is an effective way to improve crop survival in osmotic stress environments. Roots are important organs in water absorption and are involved in the initial response to osmosis stress; however, few studies have examined the underlying mechanism of tolerance to osmotic stress in watermelon roots. For better understanding of this mechanism, the inbred watermelon accession M08, which exhibits relatively high tolerance to water deficits, was treated with 20% polyethylene glycol (PEG) 6000. The root samples were harvested at 6 h after PEG treatment and untreated samples were used as controls. Transcriptome analyses were carried out by Illumina RNA sequencing. A total of 5246 differentially expressed genes were identified. Gene ontology enrichment and biochemical pathway analyses of these 5246 genes showed that short-term osmotic stress affected osmotic adjustment, signal transduction, hormone responses, cell division, cell cycle and ribosome, and M08 may repress root growth to adapt osmotic stress. The results of this study describe the watermelon root transcriptome under osmotic stress and propose new insight into watermelon root responses to osmotic stress at the transcriptome level. Accordingly, these results allow us to better understand the molecular mechanisms of watermelon in response to drought stress and will facilitate watermelon breeding projects to improve drought tolerance.

  12. Electro-osmotic flows inside triangular microchannels

    International Nuclear Information System (INIS)

    Vocale, P; Spiga, M; Geri, M; Morini, G L

    2014-01-01

    This work presents a numerical investigation of both pure electro-osmotic and combined electro-osmotic/pressure-driven flows inside triangular microchannels. A finite element analysis has been adopted to solve the governing equations for the electric potential and the velocity field, accounting for a finite thickness of the electric double layer. The influence of non-dimensional parameters such as the aspect ratio of the cross-section, the electrokinetic diameter and the ratio of the pressure force to the electric force on the flow behavior has been investigated. Numerical results point out that the velocity field is significantly influenced by the aspect ratio of the cross section and the electrokinetic diameter. More specifically, the aspect ratio plays an important role in determining the maximum volumetric flow rate, while the electrokinetic diameter is crucial to establishing the range of pressures that may be sustained by the electro-osmotic flow. Numerical results are also compared with two correlations available in the literature which enable to assess the volumetric flow rate and the pressure head for microchannels featuring a rectangular, a trapezoidal or an elliptical cross-section.

  13. Determinants of Banking System Fragility : A Regional Perspective

    NARCIS (Netherlands)

    Degryse, H.A.; Elahi, M.A.; Penas, M.F.

    2012-01-01

    Abstract: Banking systems are fragile not only within one country but also within and across regions. We study the role of regional banking system characteristics for regional banking system fragility. We find that regional banking system fragility reduces when banks in the region jointly hold more

  14. Employment Impact and Financial Burden for Families of Children with Fragile X Syndrome: Findings from the National Fragile X Survey

    Science.gov (United States)

    Ouyang, L.; Grosse, S.; Raspa, M.; Bailey, D.

    2010-01-01

    Background: The employment impact and financial burden experienced by families of children with fragile X syndrome (FXS) has not been quantified in the USA. Method: Using a national fragile X family survey, we analysed data on 1019 families with at least one child who had a full FXS mutation. Out-of-pocket expenditures related to fragile X were…

  15. Non-thermal Production of Natural betalain Colorant Concentrate from Red Beet Extract by Using the Osmotic Distillation

    Directory of Open Access Journals (Sweden)

    Nazanin Amirasgari

    2016-04-01

    Full Text Available Background and Objectives: Red beet extract concentrate can be used as a natural colorant in food products; however, destructive effects of thermal methods to produce juice concentrate decrease nutritional value in the final product. Materials and Methods: In this study, red beet extract was concentrated using osmotic distillation method, and the best pretreatment was evaluated to increase the efficiency of the concentration process. Also changes in some physicochemical properties such as betacyanins and betaxanthins contents, total phenolic compounds and antioxidant activity of red beet juice were evaluated by both the membrane and thermal concentration methods. Results: The results showed that the best concentration efficiency was obtained after pretreatment of the fresh juice with centrifugation at 1699 G for 17 min. Evaluation of the effect of both the membrane and thermal concentration processes on the physicochemical properties of juice showed that the membrane method did not change betacyanin and betaxanthin contents, total phenolic compounds, and antioxidant activity of the red beet extract. However, these properties decreased with the thermal concentration method by 26, 15, 11 and 13%, respectively. Conclusions: According to the results, osmotic distillation can produce red beet concentrate with more nutritional value than the concentrate produced with thermal method. Keywords: Membrane, Natural betalain colorant, Osmotic distillation, Red beet

  16. Method of osmotic energy harvesting using responsive compounds and molecules

    KAUST Repository

    Hu, Xiao

    2017-07-27

    The present invention discloses and claims a more efficient and economical method and system for osmotic energy production and capture using responsive compounds and molecules. The present invention is an energy harvest system enabled by stimuli responsive draw solutions that are competent in terms of energy production, geographic location flexibility, and the affordable, efficient and economical production and delivery of osmotic power. Specifically, the present invention is a novel osmotic power system that uses stimuli responsive draw solutions, economically feasible larger permeable membranes, and low grade heat sources to deliver osmotic power more efficiently and economically with less negative environmental impact, greater power output, and located in more geographically diverse areas of the world than previously thought possible for supporting such a power source.

  17. Financial fragility in the Great Moderation

    NARCIS (Netherlands)

    Bezemer, Dirk; Grydaki, Maria

    2014-01-01

    A nascent literature explores the measurement of financial fragility. This paper considers evidence for rising financial fragility during the 1984-2007 Great Moderation in the U.S. The literature suggests that macroeconomic stability combined with strong growth of credit to asset markets, in asset

  18. Drying characteristics of osmotically pretreated cranberries : Energy and quality aspects

    Energy Technology Data Exchange (ETDEWEB)

    Grabowski, S.; Marcotte, M. [Agriculture and Agri-Food Canada, St. Hyacinthe, PQ (Canada). Food Research and Development Centre; Poirier, M.; Kudra, T. [Natural Resources Canada, Varennes, PQ (Canada). CANMET Energy Technology Centre

    2002-06-01

    This paper presents the results of a study in which osmotically pretreated cranberries were dried. The osmotic treatment included dehydration and sugar infusion. The process involved pretreating halved cranberries in a standard osmotic solution followed by freeze-drying, vacuum-drying and air-drying in various dryers, such as cabinet-air-through, fluid bed, pulsed fluid bed, and vibrated fluid bed dryers. The intent was to identify the best drying technology. The comparison criteria selected were energy consumption and product quality. Product quality for freeze-dried berries was quantified based on anthocyanins content, rehydration ratio, color, and taste. Unit heat consumption could be used for selecting the drying method, as all other drying methods yielded similar but slightly lower quality products. The highest energy efficiency was obtained with the vibrated fluid bed and the pulsed fluid bed. It was noted that drying rates were reduced during the second drying period when sugar was infused into the cranberries during osmotic pretreatment, but the total energy consumption was reduced by osmotic dehydration. 22 refs., 1 tab., 5 figs.

  19. Detection of osmotic damages in GRP boat hulls

    Science.gov (United States)

    Krstulović-Opara, L.; Domazet, Ž.; Garafulić, E.

    2013-09-01

    Infrared thermography as a tool of non-destructive testing is method enabling visualization and estimation of structural anomalies and differences in structure's topography. In presented paper problem of osmotic damage in submerged glass reinforced polymer structures is addressed. The osmotic damage can be detected by a simple humidity gauging, but for proper evaluation and estimation testing methods are restricted and hardly applicable. In this paper it is demonstrated that infrared thermography, based on estimation of heat wave propagation, can be used. Three methods are addressed; Pulsed thermography, Fast Fourier Transform and Continuous Morlet Wavelet. An additional image processing based on gradient approach is applied on all addressed methods. It is shown that the Continuous Morlet Wavelet is the most appropriate method for detection of osmotic damage.

  20. Osmotic stress represses strigolactone biosynthesis in Lotus japonicus roots: exploring the interaction between strigolactones and ABA under abiotic stress

    KAUST Repository

    Liu, Junwei; He, Hanzi; Vitali, Marco; Visentin, Ivan; Charnikhova, Tatsiana V.; Haider, Imran; Schubert, Andrea; Ruyter-Spira, Carolien P.; Bouwmeester, Harro J J; Lovisolo, Claudio; Cardinale, Francesca

    2015-01-01

    Main conclusion: Strigolactone changes and cross talk with ABA unveil a picture of root-specific hormonal dynamics under stress.Abstract: Strigolactones (SLs) are carotenoid-derived hormones influencing diverse aspects of development and communication with (micro)organisms, and proposed as mediators of environmental stimuli in resource allocation processes; to contribute to adaptive adjustments, therefore, their pathway must be responsive to environmental cues. To investigate the relationship between SLs and abiotic stress in Lotus japonicus, we compared wild-type and SL-depleted plants, and studied SL metabolism in roots stressed osmotically and/or phosphate starved. SL-depleted plants showed increased stomatal conductance, both under normal and stress conditions, and impaired resistance to drought associated with slower stomatal closure in response to abscisic acid (ABA). This confirms that SLs contribute to drought resistance in species other than Arabidopsis. However, we also observed that osmotic stress rapidly and strongly decreased SL concentration in tissues and exudates of wild-type Lotus roots, by acting on the transcription of biosynthetic and transporter-encoding genes and independently of phosphate abundance. Pre-treatment with exogenous SLs inhibited the osmotic stress-induced ABA increase in wild-type roots and down-regulated the transcription of the ABA biosynthetic gene LjNCED2. We propose that a transcriptionally regulated, early SL decrease under osmotic stress is needed (but not sufficient) to allow the physiological increase of ABA in roots. This work shows that SL metabolism and effects on ABA are seemingly opposite in roots and shoots under stress.

  1. Osmotic stress represses strigolactone biosynthesis in Lotus japonicus roots: exploring the interaction between strigolactones and ABA under abiotic stress

    KAUST Repository

    Liu, Junwei

    2015-02-26

    Main conclusion: Strigolactone changes and cross talk with ABA unveil a picture of root-specific hormonal dynamics under stress.Abstract: Strigolactones (SLs) are carotenoid-derived hormones influencing diverse aspects of development and communication with (micro)organisms, and proposed as mediators of environmental stimuli in resource allocation processes; to contribute to adaptive adjustments, therefore, their pathway must be responsive to environmental cues. To investigate the relationship between SLs and abiotic stress in Lotus japonicus, we compared wild-type and SL-depleted plants, and studied SL metabolism in roots stressed osmotically and/or phosphate starved. SL-depleted plants showed increased stomatal conductance, both under normal and stress conditions, and impaired resistance to drought associated with slower stomatal closure in response to abscisic acid (ABA). This confirms that SLs contribute to drought resistance in species other than Arabidopsis. However, we also observed that osmotic stress rapidly and strongly decreased SL concentration in tissues and exudates of wild-type Lotus roots, by acting on the transcription of biosynthetic and transporter-encoding genes and independently of phosphate abundance. Pre-treatment with exogenous SLs inhibited the osmotic stress-induced ABA increase in wild-type roots and down-regulated the transcription of the ABA biosynthetic gene LjNCED2. We propose that a transcriptionally regulated, early SL decrease under osmotic stress is needed (but not sufficient) to allow the physiological increase of ABA in roots. This work shows that SL metabolism and effects on ABA are seemingly opposite in roots and shoots under stress.

  2. Investigation of the Effects of Extracellular Osmotic Pressure on Morphology and Mechanical Properties of Individual Chondrocyte.

    Science.gov (United States)

    Nguyen, Trung Dung; Oloyede, Adekunle; Singh, Sanjleena; Gu, YuanTong

    2016-06-01

    It has been demonstrated that most cells of the body respond to osmotic pressure in a systematic manner. The disruption of the collagen network in the early stages of osteoarthritis causes an increase in water content of cartilage which leads to a reduction of pericellular osmolality in chondrocytes distributed within the extracellular environment. It is therefore arguable that an insight into the mechanical properties of chondrocytes under varying osmotic pressure would provide a better understanding of chondrocyte mechanotransduction and potentially contribute to knowledge on cartilage degeneration. In this present study, the chondrocyte cells were exposed to solutions with different osmolality. Changes in their dimensions and mechanical properties were measured over time. Atomic force microscopy (AFM) was used to apply load at various strain-rates and the force-time curves were logged. The thin-layer elastic model was used to extract the elastic stiffness of chondrocytes at different strain-rates and at different solution osmolality. In addition, the porohyperelastic (PHE) model was used to investigate the strain-rate-dependent responses under the loading and osmotic pressure conditions. The results revealed that the hypo-osmotic external environment increased chondrocyte dimensions and reduced Young's modulus of the cells at all strain-rates tested. In contrast, the hyper-osmotic external environment reduced dimensions and increased Young's modulus. Moreover, using the PHE model coupled with inverse FEA simulation, we established that the hydraulic permeability of chondrocytes increased with decreasing extracellular osmolality which is consistent with previous work in the literature. This could be due to a higher intracellular fluid volume fraction with lower osmolality.

  3. Modeling osmotic salinity effects on yield characteristics of substrate-grown greenhouse crops

    NARCIS (Netherlands)

    Sonneveld, C.; Bos, van den A.L.; Voogt, W.

    2004-01-01

    In a series of experiments with different osmotic potentials in the root environment, various vegetables, and ornamentals were grown in a substrate system. The osmotic potential was varied by addition of nutrients. Yield characteristics of the crop were related to the osmotic potential of the

  4. PHOTOMETRIC EVIDENCE FOR THE OSMOTIC BEHAVIOR OF RAT LIVER MICROSOMES

    Science.gov (United States)

    Tedeschi, Henry; James, Joseph M.; Anthony, William

    1963-01-01

    Electron microscope observations are consistent with the interpretation that the elements of the endoplasmic reticulum are osmotically active in situ as well as after isolation. More recently, it has been reported that microsomal suspensions equilibrate almost completely with added C14-sucrose and that no osmotic behavior is evident from photometric data. These findings were considered at variance with the electron microscope data. However, equilibration with added label simply attests to a relatively high permeability, and, in addition, the photometric data need not be critical. Osmotic volume changes, measured photometrically, may be masked by concomitant events (e.g., changes in the refractive index of the test solutions at varying osmotic pressures, breakdown of the particles, and agglutination). For these reasons the photometric experiments were repeated. In this work, the reciprocal of optical density of microsomal suspensions was found to vary linearly with the reciprocal of concentration of the medium at constant refractive index. These changes probably correspond to osmotic volume changes, since the effect was found to be (a) independent of substance used and (b) osmotically reversible. The transmission of the suspension was found to vary with the refractive index of the medium, the concentration of particles, and the wavelength of incident light, according to relationships that are similar to or identical with those obtained for mitochondrial suspensions. PMID:14064105

  5. Use of osmotic dehydration to improve fruits and vegetables quality during processing.

    Science.gov (United States)

    Maftoonazad, Neda

    2010-11-01

    Osmotic treatment describes a preparation step to further processing of foods involving simultaneous transient moisture loss and solids gain when immersing in osmotic solutions, resulting in partial drying and improving the overall quality of food products. The different aspects of the osmotic dehydration (OD) technology namely the solutes employed, solutions characteristics used, process variables influence, as well as, the quality characteristics of the osmodehydrated products will be discussed in this review. As the process is carried out at mild temperatures and the moisture is removed by a liquid diffusion process, phase change that would be present in the other drying processes will be avoided, resulting in high quality products and may also lead to substantial energy savings. To optimize this process, modeling of the mass transfer phenomenon can improve high product quality. Several techniques such as microwave heating, vacuum, high pressure, pulsed electric field, etc. may be employed during or after osmotic treatment to enhance performance of the osmotic dehydration. Moreover new technologies used in osmotic dehydration will be discussed. Patents on osmotic dehydration of fruits and vegetables are also discussed in this article.

  6. Chromosome fragility at FRAXA in human cleavage stage embryos at risk for fragile X syndrome.

    Science.gov (United States)

    Verdyck, Pieter; Berckmoes, Veerle; De Vos, Anick; Verpoest, Willem; Liebaers, Inge; Bonduelle, Maryse; De Rycke, Martine

    2015-10-01

    Fragile X syndrome (FXS), the most common inherited intellectual disability syndrome, is caused by expansion and hypermethylation of the CGG repeat in the 5' UTR of the FMR1 gene. This expanded repeat, also known as the rare fragile site FRAXA, causes X chromosome fragility in cultured cells from patients but only when induced by perturbing pyrimidine synthesis. We performed preimplantation genetic diagnosis (PGD) on 595 blastomeres biopsied from 442 cleavage stage embryos at risk for FXS using short tandem repeat (STR) markers. In six blastomeres, from five embryos an incomplete haplotype was observed with loss of all alleles telomeric to the CGG repeat. In all five embryos, the incomplete haplotype corresponded to the haplotype carrying the CGG repeat expansion. Subsequent analysis of additional blastomeres from three embryos by array comparative genomic hybridization (aCGH) confirmed the presence of a terminal deletion with a breakpoint close to the CGG repeat in two blastomeres from one embryo. A blastomere from another embryo showed the complementary duplication. We conclude that a CGG repeat expansion at FRAXA causes X chromosome fragility in early human IVF embryos at risk for FXS. © 2015 Wiley Periodicals, Inc.

  7. The fragile X syndrome: Isolation of the FMR-1 gene and characterization of the fragile X mutation

    NARCIS (Netherlands)

    B.A. Oostra (Ben); A. Verkerk

    1992-01-01

    markdownabstractConclusion Rapid progress has been made in the analysis of the fragile X syndrome during 1991. Different groups have discovered that fragile X chromosomes are preferentially methylated. In these X chromosomes an insertion has been found in the methylated region. The FMR-1 gene,

  8. Seismic fragility capacity of equipment

    International Nuclear Information System (INIS)

    Iijima, Toru; Abe, Hiroshi; Suzuki, Kenichi

    2006-01-01

    Seismic probabilistic safety assessment (PSA) is an available method to evaluate residual risks of nuclear plants that are designed on definitive seismic conditions. From our preliminary seismic PSA analysis, horizontal shaft pumps are important components that have significant influences on the core damage frequency (CDF). An actual horizontal shaft pump and some kinds of elements were tested to evaluate realistic fragility capacities. Our test results showed that the realistic fragility capacity of horizontal shaft pump would be at least four times as high as a current value, 1.6 x 9.8 m/s 2 , used for our seismic PSA. We are going to incorporate the fragility capacity data that were obtained from those tests into our seismic PSA analysis, and we expect that the reliability of seismic PSA should increase. (author)

  9. Physicochemical characteristics of guava “Paluma” submitted to osmotic dehydration

    OpenAIRE

    Roselene Ferreira Oliveira; Lia Mara Moterlle; Edmar Clemente

    2014-01-01

    The aim of this work was to evaluate the conservation post process osmotic of guava stored temperature at 5oC. Guava (Psidium guajava L.), red variety “Paluma” minimally processed by mild osmotic dehydration, were packaged in polyethylene terephthalate (PET) and stored temperature at 5ºC. Non-treated guava, packed in PET trays, was used as control. The treatment used was osmotic dehydration in sucrose syrup at 60ºBrix and physicochemical determinations were pH, total soluble solids (TSS), tot...

  10. Seismic fragility analyses

    International Nuclear Information System (INIS)

    Kostov, Marin

    2000-01-01

    In the last two decades there is increasing number of probabilistic seismic risk assessments performed. The basic ideas of the procedure for performing a Probabilistic Safety Analysis (PSA) of critical structures (NUREG/CR-2300, 1983) could be used also for normal industrial and residential buildings, dams or other structures. The general formulation of the risk assessment procedure applied in this investigation is presented in Franzini, et al., 1984. The probability of failure of a structure for an expected lifetime (for example 50 years) can be obtained from the annual frequency of failure, β E determined by the relation: β E ∫[d[β(x)]/dx]P(flx)dx. β(x) is the annual frequency of exceedance of load level x (for example, the variable x may be peak ground acceleration), P(fI x) is the conditional probability of structure failure at a given seismic load level x. The problem leads to the assessment of the seismic hazard β(x) and the fragility P(fl x). The seismic hazard curves are obtained by the probabilistic seismic hazard analysis. The fragility curves are obtained after the response of the structure is defined as probabilistic and its capacity and the associated uncertainties are assessed. Finally the fragility curves are combined with the seismic loading to estimate the frequency of failure for each critical scenario. The frequency of failure due to seismic event is presented by the scenario with the highest frequency. The tools usually applied for probabilistic safety analyses of critical structures could relatively easily be adopted to ordinary structures. The key problems are the seismic hazard definitions and the fragility analyses. The fragility could be derived either based on scaling procedures or on the base of generation. Both approaches have been presented in the paper. After the seismic risk (in terms of failure probability) is assessed there are several approaches for risk reduction. Generally the methods could be classified in two groups. The

  11. Fragile X syndrome

    Science.gov (United States)

    ... problems, or intellectual disability may not be present. Symptoms Behavior problems associated with fragile X syndrome include: Autism spectrum disorder Delay in crawling, walking, or twisting Hand flapping ...

  12. The Detection and Analysis of Chromosome Fragile Sites

    DEFF Research Database (Denmark)

    Bjerregaard, Victoria A; Özer, Özgün; Hickson, Ian D

    2018-01-01

    A fragile site is a chromosomal locus that is prone to form a gap or constriction visible within a condensed metaphase chromosome, particularly following exposure of cells to DNA replication stress. Based on their frequency, fragile sites are classified as either common (CFSs; present in all...... for detection and analysis of chromosome fragile sites....

  13. Optimum condition of producing crisp osmotic banana using superheated steam puffing.

    Science.gov (United States)

    Tabtiang, Surapit; Prachayawarakorn, Somkiat; Soponronnarit, Somchart

    2017-03-01

    Puffing can improve textural property of snacks. Nevertheless, high temperature puffing accelerates non-enzymatic browning reactions. The osmotic treatment using sucrose solution potentially retards the browning, but the high amount of sucrose gain causes hard texture. The objective of this work was therefore to study the effects of osmotic time, puffing time and puffing temperature on banana qualities such as colour, shrinkage and textural property. The experimental results showed that puffing temperature, puffing time and osmotic time significantly affected colour, shrinkage and textual properties. The optimisation using response surface methodology was used for a trade-off between colour and textural properties. To obtain a good quality product, the puffed osmotic banana should be operated at the osmotic time of 43 min and puffing temperature of 220 °C and puffing time of 2 min. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  14. Soybean mother plant exposure to temperature stress and its effect on germination under osmotic stress

    International Nuclear Information System (INIS)

    Khalil, S.K.; Rehman, A.; Khan, A.Z.; Mexal, J.G.; Zubair, M.; Wahab, S.; Khalil, I.H.; Mohammad, F.

    2010-01-01

    High temperature reduces quality of soybean seed developed at different positions on the plant. The objective of this research was to study the quality of seed produced under different temperature regimes located at different position in the canopy. Soybean plants grown in pots were transferred at first pod stage to three growth chambers fixed at 18/10, 25/15 and 32/20 deg. C day/night temperature having 13/11 hrs day/night length. The plants remained in growth chambers until physiological maturity. Seeds harvested from each growth chamber were exposed to osmotic stress having osmotic potential of -0.5 MPa and unstressed control. Both stressed and control treatments were germinated in three growth chambers fixed at 18, 25 and 35 deg. C. Seed developed at lowest temperature (18/10 deg. C day/night) had maximum germination. Germination decreased linearly with increased day/night temperature and lowest germination was recorded at highest temperature of 32/20 deg. C (day/night). Seed developed at bottom position was heaviest and had better germination compared with seed developed at middle and top position. Seed germination was highest at 25 deg. C and took fewer days to 50% germination than 18 and 25 deg. C. Osmotic stress decreased germination and delayed days to 50% germination than control. It can be concluded that optimum temperature for seed development was 18/10 deg. C (day/night) whereas best germination temperature was 25 deg. C. (author)

  15. Osmotic stress upregulates the transcription of thiamine (vitamin B1 ...

    African Journals Online (AJOL)

    Osmotic stress upregulates the transcription of thiamine (vitamin B1) ... Oil palm's responses in terms of the expression profiles of these two thiamine biosynthesis genes to an osmotic stress inducer, polyethylene glycol ... from 32 Countries:.

  16. Osmotic Compounds Enhance Antibiotic Efficacy against Acinetobacter baumannii Biofilm Communities.

    Science.gov (United States)

    Falghoush, Azeza; Beyenal, Haluk; Besser, Thomas E; Omsland, Anders; Call, Douglas R

    2017-10-01

    Biofilm-associated infections are a clinical challenge, in part because a hydrated matrix protects the bacterial community from antibiotics. Herein, we evaluated how different osmotic compounds (maltodextrin, sucrose, and polyethylene glycol [PEG]) enhance antibiotic efficacy against Acinetobacter baumannii biofilm communities. Established (24-h) test tube biofilms (strain ATCC 17978) were treated with osmotic compounds in the presence or absence of 10× the MIC of different antibiotics (50 μg/ml tobramycin, 20 μg/ml ciprofloxacin, 300 μg/ml chloramphenicol, 30 μg/ml nalidixic acid, or 100 μg/ml erythromycin). Combining antibiotics with hypertonic concentrations of the osmotic compounds for 24 h reduced the number of biofilm bacteria by 5 to 7 log ( P baumannii strains were similarly treated with 400-Da PEG and tobramycin, resulting in a mean 2.7-log reduction in recoverable bacteria compared with tobramycin treatment alone. Multivariate regression models with data from different osmotic compounds and nine antibiotics demonstrated that the benefit from combining hypertonic treatments with antibiotics is a function of antibiotic mass and lipophilicity ( r 2 > 0.82; P baumannii and Escherichia coli K-12. Augmenting topical antibiotic therapies with a low-mass hypertonic treatment may enhance the efficacy of antibiotics against wound biofilms, particularly when using low-mass hydrophilic antibiotics. IMPORTANCE Biofilms form a barrier that protects bacteria from environmental insults, including exposure to antibiotics. We demonstrated that multiple osmotic compounds can enhance antibiotic efficacy against Acinetobacter baumannii biofilm communities, but viscosity is a limiting factor, and the most effective compounds have lower molecular mass. The synergism between osmotic compounds and antibiotics is also dependent on the hydrophobicity and mass of the antibiotics. The statistical models presented herein provide a basis for predicting the optimal combination of

  17. Diminuição da fragilidade osmótica eritrocitária na leptospirose canina

    OpenAIRE

    Santoro, Marcelo L.; Kogika, Marcia M.; Hagiwara, Mitika K.; Mirandola, Regina M. S.; Castelar, Izaura L. C. G.

    1994-01-01

    Erythrocyte osmotic fragility (EOF) was carried out in nineteen dogs naturally infected by Leptospira interrogans serovar icterohaemorrhagiae/copenhagi. A decreased EOF was observed, suggesting a modification of erythrocyte components secondary to disturbances that occur during canine leptospirosis, such as renal damage and hepatic disease.A fragilidade osmótica eritrocitária foi estudada em dezenove cães infectados naturalmente pela Leptospira interrogans serovar icterohaemorrhagiae/copenhag...

  18. Osmotic Power: A Fresh Look at an Old Experiment

    Science.gov (United States)

    Dugdale, Pam

    2014-01-01

    Electricity from osmotic pressure might seem a far-fetched idea but this article describes a prototype in Norway where the osmotic pressure generated between salt and fresh water drives a turbine. This idea was applied in a student investigation, where they were tasked with researching which alternative materials could be used for the…

  19. Osmotic Pressure Simulations of Amino Acids and Peptides Highlight Potential Routes to Protein Force Field Parameterization

    Science.gov (United States)

    Miller, Mark S.; Lay, Wesley K.

    2016-01-01

    Recent molecular dynamics (MD) simulations of proteins have suggested that common force fields overestimate the strength of amino acid interactions in aqueous solution. In an attempt to determine the causes of these effects, we have measured the osmotic coefficients of a number of amino acids using the AMBER ff99SB-ILDN force field with two popular water models, and compared the results with available experimental data. With TIP4P-Ew water, interactions between aliphatic residues agree well with experiment, but interactions of the polar residues serine and threonine are found to be excessively attractive. For all tested amino acids, the osmotic coefficients are lower when the TIP3P water model is used. Additional simulations performed on charged amino acids indicate that the osmotic coefficients are strongly dependent on the parameters assigned to the salt ions, with a reparameterization of the sodium:carboxylate interaction reported by the Aksimentiev group significantly improving description of the osmotic coefficient for glutamate. For five neutral amino acids, we also demonstrate a decrease in solute-solute attractions using the recently reported TIP4P-D water model and using the KBFF force field. Finally, we show that for four two-residue peptides improved agreement with experiment can be achieved by re-deriving the partial charges for each peptide. PMID:27052117

  20. Behavioral Phenotype of Fragile X Syndrome in Adolescence and Adulthood

    Science.gov (United States)

    Smith, Leann E.; Barker, Erin T.; Seltzer, Marsha Mailick; Abbeduto, Leonard; Greenberg, Jan S.

    2012-01-01

    The present study explored the behavioral profile of individuals with fragile X syndrome during adolescence and adulthood. Individuals with both fragile X syndrome and autism (n = 30) were compared with (a) individuals diagnosed with fragile X syndrome (but not autism; n = 106) and (b) individuals diagnosed with autism (but not fragile X syndrome;…

  1. An analysis of electro-osmotic and magnetohydrodynamic heat pipes

    International Nuclear Information System (INIS)

    Harrison, M.A.

    1988-01-01

    Mechanically simple methods of improving heat transport in heat pipes are investigated. These methods are electro-osmotic and magnetohydrodynamic augmentation. For the electro-osmotic case, a detailed electrokinetic model is used. The electrokinetic model used includes the effects of pore surface curvature and multiple ion diffusivities. The electrokinetic model is extended to approximate the effects of elevated temperature. When the electro-osmotic model is combined with a suitable heat-pipe model, it is found that the electro-osmotic pump should be a thin membrane. Arguments are provided that support the use of a volatile electrolyte. For the magnetohydrodynamic case, a brief investigation is provided. A quasi-one-dimensional hydromagnetic duct flow model is used. This hydromagnetic model is extended to approximate flow effects unique to heat pipes. When combined with a suitable heat pipe model, it is found that there is no performance gain for the case considered. In fact, there are serious pressure-distribution problems that have not been previously recognized. Potential solutions to these pressure-distribution problems are suggested

  2. Effect of pore structure on chemico-osmotic, diffusion and hydraulic properties of mud-stones

    International Nuclear Information System (INIS)

    Takeda, M.; Manaka, M.; Ito, K.; Miyoshi, S.; Tokunaga, T.

    2012-01-01

    Formations in the Horonobe research area of Japan, where the Japan Atomic Energy Agency (JAEA) has been operating an Underground Research Laboratory. The rock samples are of cylindrical shape with 50 mm in diameter and 10 mm in length. The rock samples were immersed in 0.1 M NaCl solutions before experiments. The densities, specific surface area and cation exchange capacity were measured for the remains of drill cores from which the samples were taken. Pore radius distribution, average pore radius and porosity were also evaluated for each drill cores by mercury porosimetry. The permeability and chemical-osmosis experiments were performed in sequence on each rock sample under the confining pressures simulating in-situ effective stress condition. 0.1 M NaCl solution was used as permeant fluid in the permeability experiment, and the same solution was used as initial solution in the subsequent chemical-osmosis experiment. In the permeability experiment, a constant pressure was applied to the upper surface of rock sample. In the chemical-osmosis experiment, the bottom reservoir solution was replaced with 0.6 M NaCl solution. Both experiments were performed with the bottom reservoir isolated from the pressure buffer tank, and the progress of each experiment was monitored by measuring the bottom reservoir pressure. Figure 2 shows the chemico-osmotic, diffusion and hydraulic parameters determined for the Koetoi and Wakkanai mud-stone samples as functions of porosity. The diffusion and hydraulic parameters of these samples generally decrease with the decrease of porosity, while the osmotic efficiency is not a simple function of porosity. A relatively large osmotic efficiency was obtained only from a Wakkanai mud-stone sample with porosity of 0.33. The Wakkanai mud-stone samples have similar average pore radius, ranging from 6.8 to 7.6 nm; however, the Wakkanai mud-stone samples without large osmotic efficiency have bimodal pore structures. These suggest that even if small size pores

  3. Autism Spectrum Disorder and Fragile X Syndrome

    Science.gov (United States)

    ... only after another family member has been diagnosed. Autism Spectrum Disorder and Fragile X Syndrome Fragile X syndrome is ... gene cause of ASD What Is Autism Spectrum Disorder? Autism spectrum disorder (ASD) is a behavioral diagnosis. The range ...

  4. Relay testing parametric investigation of seismic fragility

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.; Hofmayer, C.; Kassir, M.; Pepper, S.

    1989-01-01

    The seismic capacity of most electrical equipment is governed by malfunction of relays. An evaluation of the existing relay test data base at Brookhaven National Laboratory (BNL) has indicated that the seismic fragility of a relay may depend on various parameters related to the design or the input motion. In particular, the electrical mode, contact state, adjustment, chatter duration acceptance limit, and the frequency and the direction of the vibration input have been considered to influence the relay fragility level. For a particular relay type, the dynamics of its moving parts depends on the exact model number and vintage and hence, these parameters may also influence the fragility level. In order to investigate the effect of most of these parameters on the seismic fragility level, BNL has conducted a relay test program. The testing has been performed at Wyle Laboratories. Establishing the correlation between the single frequency fragility test input and the corresponding multifrequency response spectrum (TRS) is also an objective of this test program. This paper discusses the methodology used for testing and presents a brief summary of important test results. 1 ref., 10 figs

  5. Seismic fragility of nuclear power plant components (Phase II)

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.; Kassir, M.K.; Pepper, S.E.

    1990-02-01

    As part of the Component Fragility Program which was initiated in FY 1985, three additional equipment classes have been evaluated. This report contains the fragility results and discussions on these equipment classes which are switchgear, I and C panels and relays. Both low and medium voltage switchgear assemblies have been considered and a separate fragility estimate for each type is provided. Test data on cabinets from the nuclear instrumentation/neutron monitoring system, plant/process protection system, solid state protective system and engineered safeguards test system comprise the BNL data base for I and C panels (NSSS). Fragility levels have been determined for various failure modes of switchgear and I ampersand C panels, and the deterministic results are presented in terms of test response spectra. In addition, the test data have been evaluated for estimating the respective probabilistic fragility levels which are expressed in terms of a median value, an uncertainty coefficient, a randomness coefficient and an HCLPF value. Due to a wide variation of relay design and the fragility level, a generic fragility level cannot be established for relays. 7 refs., 13 figs., 12 tabs

  6. Resilience and the Fragile City

    Directory of Open Access Journals (Sweden)

    John de Boer

    2015-04-01

    Full Text Available Humanitarian, security, and development actors are witnessing two distinct but intertwined trends that will have a dramatic impact on their operations. The first relates to the fact that the locus of global poverty and vulnerability to disaster are increasingly concentrated in fragile and conflict affected states. The second trend is associated with the notion that the world has entered a period of unprecedented urbanization. For the first time in history, more people live inside urban centres than outside of them. As the world continues to urbanize, global emergencies will increasingly be concentrated in cities, particularly in lower income and fragile countries where the pace of urbanization is fastest. Yet, despite the growing risks facing urban populations living in fragile and conflict affected countries, there is very little understanding of what can be done to reduce the risks posed to these cities and their populations.

  7. Seismic fragility levels of nuclear power plant equipment

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.

    1987-01-01

    Seismic fragility levels of safety-related electrical and mechanical equipment used in nuclear power plants are discussed. The fragility level is defined as the vibration level corresponding to initiation of equipment malfunctions. The test response spectrum is used as a measure of this vibration level. The fragility phenomenon of an equipment is represented by a number of response spectra corresponding to various failure modes. Analysis methods are described for determination of the fragility level by use of existing test data. Useful conversion factors are tabulated to transform test response spectra from one damping value to another. Results are presented for switch-gears and motor control centers. The capacity levels of these equipment assemblies are observed to be limited by malfunctioning of contactors, motor starters, relays and/or switches. The applicability of the fragility levels, determined in terms of test response spectra, to Seismic Margin Studies and Probabilistic Risk Assessments is discussed and specific recommendations are provided

  8. Faba Bean Can Adapt to Chocolate Spot Disease by Pretreatment with Shikimic and Salicylic Acids through Osmotic Adjustment, Solutes Allocation and Leaf Turgidity

    Directory of Open Access Journals (Sweden)

    Heshmat S. Aldesuquy

    2014-03-01

    Full Text Available This study investigated the effect of shikimic and salicylic acids at the concentrations of 0.4 and 0.7 mM, respectively, or their combination as phenolic compounds and Ridomil MZ at the concentration of 250 g/100 L as a fungicide on osmotic pressure (OP, solutes allocation, organic acids, inorganic ions and relative water content were quantified in Vicia faba leaves infected by Botrytis fabae. Pathogen induced noticeable decrease in osmotic pressure, total soluble sugar (TSS and inorganic osmolytes (i.e. Na+, K+, Ca2+, Mg2+ and Cl- while caused obvious increase in proline, total soluble nitrogen (TSN and organic acids (i.e. Keto and citric acids in water extract of the leaf of faba bean plants. Furthermore, pathogen caused marked decrease in relative water content (RWC of infected leaves and as a consequence the saturation water deficit (SWD was increased. Exogenous application of shikimic acid, salicylic acid or their combination could counteract the adverse effects of B. fabae on osmotic adjustment by inducing additional increase in proline, total soluble sugars, total soluble nitrogen and organic acids which in turn increase the osmotic pressure as well as relative water content in leaves of infected plants. Recovery of osmotic adjustment as well as leaf turgidity of infected host by using these chemical inducers may encourage the using of them as protective control means. The results of the present study showed also that the application of chemical inducers such as shikimic and salicylic acids or their interaction increased the resistance of Vicia faba against the chocolate spot disease.

  9. Fouling in Membrane Distillation, Osmotic Distillation and Osmotic Membrane Distillation

    Directory of Open Access Journals (Sweden)

    Mourad Laqbaqbi

    2017-03-01

    Full Text Available Various membrane separation processes are being used for seawater desalination and treatment of wastewaters in order to deal with the worldwide water shortage problem. Different types of membranes of distinct morphologies, structures and physico-chemical characteristics are employed. Among the considered membrane technologies, membrane distillation (MD, osmotic distillation (OD and osmotic membrane distillation (OMD use porous and hydrophobic membranes for production of distilled water and/or concentration of wastewaters for recovery and recycling of valuable compounds. However, the efficiency of these technologies is hampered by fouling phenomena. This refers to the accumulation of organic/inorganic deposits including biological matter on the membrane surface and/or in the membrane pores. Fouling in MD, OD and OMD differs from that observed in electric and pressure-driven membrane processes such electrodialysis (ED, membrane capacitive deionization (MCD, reverse osmosis (RO, nanofiltration (NF, ultrafiltration (UF, microfiltration (MF, etc. Other than pore blockage, fouling in MD, OD and OMD increases the risk of membrane pores wetting and reduces therefore the quantity and quality of the produced water or the concentration efficiency of the process. This review deals with the observed fouling phenomena in MD, OD and OMD. It highlights different detected fouling types (organic fouling, inorganic fouling and biofouling, fouling characterization techniques as well as various methods of fouling reduction including pretreatment, membrane modification, membrane cleaning and antiscalants application.

  10. A Simple Student Laboratory on Osmotic Flow, Osmotic Pressure, and the Reflection Coefficient.

    Science.gov (United States)

    Feher, Joseph J.; Ford, George D.

    1995-01-01

    Describes a laboratory exercise containing a practical series of experiments that novice students can perform within two hours. The exercise provides a confirmation of van't Hoff's law while placing more emphasis on osmotic flow than pressure. Students can determine parameters such as the reflection coefficient which stress the interaction of both…

  11. Physicochemical characteristics of guava “Paluma” submitted to osmotic dehydration

    Directory of Open Access Journals (Sweden)

    Roselene Ferreira Oliveira

    2014-09-01

    Full Text Available The aim of this work was to evaluate the conservation post process osmotic of guava stored temperature at 5oC. Guava (Psidium guajava L., red variety “Paluma” minimally processed by mild osmotic dehydration, were packaged in polyethylene terephthalate (PET and stored temperature at 5ºC. Non-treated guava, packed in PET trays, was used as control. The treatment used was osmotic dehydration in sucrose syrup at 60ºBrix and physicochemical determinations were pH, total soluble solids (TSS, total titratable acidity (TTA, reducing sugars (RS, total sugars (TS and parameters related to colour read (a*, chroma (c*, yellow (b*, luminosity (L* of the fresh and osmotically dehydrated guava slices. The dehydrated fruits lost about 34.45% of water, concentrating contents of soluble solids, total and reducing sugars, when compared to control samples. The pH value remained around 3.76 for the OD fruits and 3.87 for the fresh fruits. The colour of the dehydrated fruits was more intense than the control samples’. The guava slices osmotic dehydration had 21 days of shelf life, showed physicochemical characteristics significantly superior to the control samples’, having a stable and high quality product as a result.

  12. Study on the Progress of Ecological Fragility Assessment in China

    Science.gov (United States)

    Chen, Pei; Hou, Kang; Chang, Yue; Li, Xuxiang; Zhang, Yunwei

    2018-02-01

    The basic elements of human survival are based on the ecological environment. The development of social economic and the security of the ecological environment are closely linked and interact with each other. The fragility of the environment directly affects the stability of the regional ecosystem and the sustainable development of the ecological environment. As part of the division of the national ecological security, the assessment of ecological fragility has become a hot and difficult issue in environmental research, and researchers at home and abroad have systematically studied the causes and states of ecological fragility. The assessment of regional ecological fragility is a qualitative and quantitative analysis of the unbalanced distribution of ecological environment factors caused by human socio-economic activities or changes in ecosystems. At present, researches on ecological fragility has not formed a complete and unified index assessment system, and the unity of the assessment model has a direct impact on the accuracy of the index weights. Therefore, the discussion on selection of ecological fragility indexes and the improvement of ecological fragility assessment model is necessary, which is good for the improvement of ecological fragility assessment system in China.

  13. Frequency of fragile-x in x‑linked mental retardation

    African Journals Online (AJOL)

    ... with isolated mental retardation or autism of unknown etiology with considerable fragile X dysmorphic features or established family history of fragile X syndrome, chromosomal study that identifies the fragile site at Xq27.3 in addition to other cytogenetic abnormalities could be useful or early diagnosis and intervention by ...

  14. Repeat-mediated epigenetic dysregulation of the FMR1 gene in the fragile X-related disorders.

    Science.gov (United States)

    Usdin, Karen; Kumari, Daman

    2015-01-01

    The fragile X-related disorders are members of the Repeat Expansion Diseases, a group of genetic conditions resulting from an expansion in the size of a tandem repeat tract at a specific genetic locus. The repeat responsible for disease pathology in the fragile X-related disorders is CGG/CCG and the repeat tract is located in the 5' UTR of the FMR1 gene, whose protein product FMRP, is important for the proper translation of dendritic mRNAs in response to synaptic activation. There are two different pathological FMR1 allele classes that are distinguished only by the number of repeats. Premutation alleles have 55-200 repeats and confer risk of fragile X-associated tremor/ataxia syndrome and fragile X-associated primary ovarian insufficiency. Full mutation alleles on the other hand have >200 repeats and result in fragile X syndrome, a disorder that affects learning and behavior. Different symptoms are seen in carriers of premutation and full mutation alleles because the repeat number has paradoxical effects on gene expression: Epigenetic changes increase transcription from premutation alleles and decrease transcription from full mutation alleles. This review will cover what is currently known about the mechanisms responsible for these changes in FMR1 expression and how they may relate to other Repeat Expansion Diseases that also show repeat-mediated changes in gene expression.

  15. The effects of exogenous proline and osmotic stress on morpho ...

    African Journals Online (AJOL)

    USER

    2010-06-21

    Jun 21, 2010 ... For evaluation of growth parameters of strawberry callus under osmotic stress and exogenous proline, embryonic calli were transferred to Murashige and Skoog (MS) medium containing four sucrose. (osmotic stress) treatments including 3, 6, 9 and 12% and various concentrations of exogenous L- proline ...

  16. Swelling, mechanical and friction properties of PVA/PVP hydrogels after swelling in osmotic pressure solution.

    Science.gov (United States)

    Shi, Yan; Xiong, Dangsheng; Liu, Yuntong; Wang, Nan; Zhao, Xiaoduo

    2016-08-01

    The potential of polyvinyl alcohol/polyvinylpyrrolidone (PVA/PVP) hydrogels as articular cartilage replacements was in vitro evaluated by using a macromolecule-based solution to mimic the osmotic environment of cartilage tissue. The effects of osmotic pressure solution on the morphology, crystallinity, swelling, mechanical and friction properties of PVA/PVP hydrogels were investigated by swelling them in non-osmotic and osmotic pressure solutions. The results demonstrated that swelling ratio and equilibrium water content were greatly reduced by swelling in osmotic solution, and the swelling process was found to present pseudo-Fickian diffusion character. The crystallization degree of hydrogels after swelling in osmotic solution increased more significantly when it compared with that in non-osmotic solution. After swelling in osmotic solution for 28days, the compressive tangent modulus and storage modulus of hydrogels were significantly increased, and the low friction coefficient was reduced. However, after swelling in the non-osmotic solution, the compressive tangent modulus and friction coefficient of hydrogels were comparable with those of as-prepared hydrogels. The better material properties of hydrogels in vivo than in vitro evaluation demonstrated their potential application in cartilage replacement. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Osmotic actuation for microfluidic components in point-of-care applications

    KAUST Repository

    Chen, Yu-Chih

    2013-01-01

    We present a novel design of micropumps and valves driven by osmotic force for point-of-care applications. Although there have been significant progresses in microfluidic components and control devices such as fluidic diodes, switches, resonators and digital-to-analog converters, the ultimate power source still depends on bulky off-chip components, which are expensive and cannot be easily miniaturized. For point-of-care applications, it is critical to integrate all the components in a compact size at low cost. In this work, we report two key active components actuated by osmotic mechanism for total integrated microfluidic system. For the proof of concept, we have demonstrated valve actuation, which can maintain stable ON/OFF switching operations under 125 kPa back pressure. We have also implemented an osmotic pump, which can pump a high flow rate over 30 μL/min for longer than 30 minutes. The experimental data demonstrates the possibility and potential of applying osmotic actuation in point-of-care disposable microfluidics. © 2013 IEEE.

  18. Osmotic dehydration of fish: principal component analysis

    Directory of Open Access Journals (Sweden)

    Lončar Biljana Lj.

    2014-01-01

    Full Text Available Osmotic treatment of the fish Carassius gibelio was studied in two osmotic solutions: ternary aqueous solution - S1, and sugar beet molasses - S2, at three solution temperatures of 10, 20 and 30oC, at atmospheric pressure. The aim was to examine the influence of type and concentration of the used hypertonic agent, temperature and immersion time on the water loss, solid gain, dry mater content, aw and content of minerals (Na, K, Ca and Mg. S2 solution has proven to be the best option according to all output variables.[ Projekat Ministarstva nauke Republike Srbije, br. TR 31055

  19. Component fragilities. Data collection, analysis and interpretation

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.

    1985-01-01

    As part of the component fragility research program sponsored by the US NRC, BNL is involved in establishing seismic fragility levels for various nuclear power plant equipment with emphasis on electrical equipment. To date, BNL has reviewed approximately seventy test reports to collect fragility or high level test data for switchgears, motor control centers and similar electrical cabinets, valve actuators and numerous electrical and control devices, e.g., switches, transmitters, potentiometers, indicators, relays, etc., of various manufacturers and models. BNL has also obtained test data from EPRI/ANCO. Analysis of the collected data reveals that fragility levels can best be described by a group of curves corresponding to various failure modes. The lower bound curve indicates the initiation of malfunctioning or structural damage, whereas the upper bound curve corresponds to overall failure of the equipment based on known failure modes occurring separately or interactively. For some components, the upper and lower bound fragility levels are observed to vary appreciably depending upon the manufacturers and models. For some devices, testing even at the shake table vibration limit does not exhibit any failure. Failure of a relay is observed to be a frequent cause of failure of an electrical panel or a system. An extensive amount of additional fregility or high level test data exists

  20. The effects of exogenous proline and osmotic stress on morpho ...

    African Journals Online (AJOL)

    For evaluation of growth parameters of strawberry callus under osmotic stress and exogenous proline, embryonic calli were transferred to Murashige and Skoog (MS) medium containing four sucrose (osmotic stress) treatments including 3, 6, 9 and 12% and various concentrations of exogenous Lproline (0, 2.5, 5 and 10 ...

  1. BANKING SYSTEM FRAGILITY: CASE OF THE REPUBLIC OF MOLDOVA

    Directory of Open Access Journals (Sweden)

    Dorina CLICHICI

    2014-04-01

    Full Text Available The paper studied the determinants of Moldovan banking system fragility. It underlines the existing researches into the empirical determinants of banking fragility. The analysis revealed that there are numerous channels through which weaknesses within the macroeconomic conditions and structural characteristics might increase banking system fragility. The main macroeconomic determinants which may have an impact on Moldovan banking system fragility are: excessive domestic liquidity, pro-cyclical character of the banking system, dependence on remittances, financial dollarization. There are also several banking characteristics which play a role for Moldovan banking system fragility: the undermined intermediation function, high level of bad loans, uncertainties in the ownership structure, low presence of foreign strategic investors. The paper employed a quantitative, a qualitative and a comparative analysis using the financial soundness and structural indicators of the Moldovan banking system in order to assess the impact of various determinants on Moldovan banking system fragility. The results reveal a high degree of capitalization and liquidity of Moldovan banking system, factors which contribute and maintain the general stability of the entire financial system.

  2. Longitudinal Profiles of Adaptive Behavior in Fragile X Syndrome

    Science.gov (United States)

    Quintin, Eve-Marie; Jo, Booil; Lightbody, Amy A.; Hazlett, Heather Cody; Piven, Joseph; Hall, Scott S.; Reiss, Allan L.

    2014-01-01

    OBJECTIVE: To examine longitudinally the adaptive behavior patterns in fragile X syndrome. METHOD: Caregivers of 275 children and adolescents with fragile X syndrome and 225 typically developing children and adolescents (2–18 years) were interviewed with the Vineland Adaptive Behavior Scales every 2 to 4 years as part of a prospective longitudinal study. RESULTS: Standard scores of adaptive behavior in people with fragile X syndrome are marked by a significant decline over time in all domains for males and in communication for females. Socialization skills are a relative strength as compared with the other domains for males with fragile X syndrome. Females with fragile X syndrome did not show a discernible pattern of developmental strengths and weaknesses. CONCLUSIONS: This is the first large-scale longitudinal study to show that the acquisition of adaptive behavior slows as individuals with fragile X syndrome age. It is imperative to ensure that assessments of adaptive behavior skills are part of intervention programs focusing on childhood and adolescence in this condition. PMID:25070318

  3. Fragile Butterfly

    DEFF Research Database (Denmark)

    2011-01-01

    Valg af materiale/medie/form: Med indlevelse og en unik balance af sårbarhed i stemmen synger og fortolker Heidie sine egne sange, hvis lyriske tekster grundlæggende har to temaer: En dyb kærlighed til livet og det at turde kærligheden. Toneuniverset i Fragile Butterfly tager sit afsæt i jazzen...

  4. Tracking development assistance for health to fragile states: 2005-2011.

    Science.gov (United States)

    Graves, Casey M; Haakenstad, Annie; Dieleman, Joseph L

    2015-03-19

    Development assistance for health (DAH) has grown substantially, totaling more than $31.3 billion in 2013. However, the degree that countries with high concentrations of armed conflict, ethnic violence, inequality, debt, and corruption have received this health aid and how that assistance might be different from the funding provided to other countries has not been assessed. We combine DAH estimates and a multidimensional fragile states index for 2005 through 2011. We disaggregate and compare total DAH disbursed for fragile states versus stable states. Between 2005 and 2011, DAH per person in fragile countries increased at an annualized rate of 5.4%. In 2011 DAH to fragile countries totaled $6.2 billion, which is $5.05 per person. This is 43% of total DAH that is traced to a country. Comparing low-income countries, funding channeled to fragile countries was $7.22 per person while stable countries received $11.15 per person. Relative to stable countries, donors preferred to provide more funding to low-income fragile countries that have refugees or ongoing external intervention but tended to avoid providing funding to countries with political gridlock, flawed elections, or economic decline. In 2011, Ethiopia received the most health aid of all fragile countries, while the United States provided the most funds to fragile countries. In 2011, 1.2 billion people lived in fragile countries. DAH can bolster health systems and might be especially valuable in providing long-term stability in fragile environments. While external health funding to these countries has increased since 2005, it is, in per person terms, almost half as much as the DAH provided to stable countries of comparable income levels.

  5. Title: Potassium application regulates nitrogen metabolism and osmotic adjustment in cotton (Gossypium hirsutum L.) functional leaf under drought stress.

    Science.gov (United States)

    Zahoor, Rizwan; Zhao, Wenqing; Abid, Muhammad; Dong, Haoran; Zhou, Zhiguo

    2017-08-01

    To evaluate the role of potassium (K) in maintaining nitrogen metabolism and osmotic adjustment development of cotton functional leaves to sustain growth under soil drought and rewatering conditions, the plants of two cotton cultivars Siza 3 (low-K sensitive) and Simian 3 (low-K tolerant), were grown under three different K rates (K0, K1, and K2; 0, 150, and 300kgK 2 Oha -1 , respectively) and exposed to drought stress with 40±5% soil relative water content (SRWC). The drought stress was applied at flowering stage by withholding water for eight days followed by rewatering to a well-watered level (75±5% SRWC). The results showed that drought-stressed plants of both cultivars showed a decrease in leaf relative water content (RWC) and osmotic potential in the functional leaves and developed osmotic adjustment with an increase in the contents of free amino acids, soluble sugars, inorganic K, and nitrate as compared to well-watered plants. In drought-stressed plants, nitrogen-metabolizing enzyme activities of nitrogen reductase (NR), glutamine synthetase (GS), and glutamate synthase (GOGAT) were diminished significantly (P≤0.05) along with decreased chlorophyll content and soluble proteins. However, drought-stressed plants under K application not only exhibited higher osmotic adjustment with greater accumulation of osmolytes but also regulated nitrogen metabolism by maintaining higher enzyme activities, soluble proteins, and chlorophyll content in functional leaves as compared to the plants without K application. Siza 3 showed better stability in enzyme activities and resulted in 89% higher seed cotton yield under K2 as compared to K0 in drought-stressed plants, whereas this increase was 53% in the case of Simian 3. The results of the study suggested that K application enhances cotton plants' potential for sustaining high nitrogen-metabolizing enzyme activities and related components to supplement osmotic adjustment under soil drought conditions. Copyright © 2017

  6. A note on families of fragility curves

    International Nuclear Information System (INIS)

    Kaplan, S.; Bier, V.M.; Bley, D.C.

    1989-01-01

    In the quantitative assessment of seismic risk, uncertainty in the fragility of a structural component is usually expressed by putting forth a family of fragility curves, with probability serving as the parameter of the family. Commonly, a lognormal shape is used both for the individual curves and for the expression of uncertainty over the family. A so-called composite single curve can also be drawn and used for purposes of approximation. This composite curve is often regarded as equivalent to the mean curve of the family. The equality seems intuitively reasonable, but according to the authors has never been proven. The paper presented proves this equivalence hypothesis mathematically. Moreover, the authors show that this equivalence hypothesis between fragility curves is itself equivalent to an identity property of the standard normal probability curve. Thus, in the course of proving the fragility curve hypothesis, the authors have also proved a rather obscure, but interesting and perhaps previously unrecognized, property of the standard normal curve

  7. Osmotic consolidation of suspensions and gels

    International Nuclear Information System (INIS)

    Miller, K.T.; Zukoski, C.F.

    1994-01-01

    An osmotic method for the consolidation of suspensions of ceramic particles is demonstrated. Concentrated solutions of poly(ethylene oxide) are separated from a suspension of ceramic particles by a semipermeable membrane, creating a gradient in solvent chemical potential. Solvent passes from the suspension into the polymer solution, lowering its free energy and consolidating the suspension. Dispersions of stable 8-nm hydrous zirconia particles were consolidated to over 47% by volume. Suspensions of α-alumina in three states of aggregation (dispersed, weakly flocculated, and strongly flocculated) were consolidated to densities greater than or equal to those produced in conventional pressure filtration. Moreover, the as-consolidated alumina bodies were partially drained of fluid during the osmotic consolidation process, producing cohesive partially dried bodies with improved handling characteristics

  8. Recent experimental data may point to a greater role for osmotic pressures in the subsurface

    Science.gov (United States)

    Neuzil, C.E.; Provost, A.M.

    2009-01-01

    Uncertainty about the origin of anomalous fluid pressures in certain geologic settings has caused researchers to take a second look at osmosis, or flow driven by chemical potential differences, as a pressure‐generating process in the subsurface. Interest in geological osmosis has also increased because of an in situ experiment by Neuzil (2000) suggesting that Pierre Shale could generate large osmotic pressures when highly compacted. In the last few years, additional laboratory and in situ experiments have greatly increased the number of data on osmotic properties of argillaceous formations, but they have not been systematically examined. In this paper we compile these data and explore their implications for osmotic pressure generation in subsurface systems. Rather than base our analysis on osmotic efficiencies, which depend strongly on concentration, we calculated values of a quantity we term osmotic specific surface area (Aso) that, in principle, is a property of the porous medium only. The Aso values are consistent with a surprisingly broad spectrum of osmotic behavior in argillaceous formations, and all the formations tested exhibited at least a modest ability to generate osmotic pressure. It appears possible that under appropriate conditions some formations can be highly effective osmotic membranes able to generate osmotic pressures exceeding 30 MPa (3 km of head) at porosities as high as ∼0.1 and pressures exceeding 10 MPa at porosities as high as ∼0.2. These findings are difficult to reconcile with the lack of compelling field evidence for osmotic pressures, and we propose three explanations for the disparity: (1) Our analysis is flawed and argillaceous formations are less effective osmotic membranes than it suggests; (2) the necessary subsurface conditions, significant salinity differences within intact argillaceous formations, are rare; or (3) osmotic pressures are unlikely to be detected and are not recognized when encountered. The last possibility

  9. Gene expression analysis in response to osmotic stimuli in the intervertebral disc with DNA microarray.

    Science.gov (United States)

    Zhang, Wenzhi; Li, Xu; Shang, Xifu; Zhao, Qichun; Hu, Yefeng; Xu, Xiang; He, Rui; Duan, Liqun; Zhang, Feng

    2013-12-27

    Intervertebral disc (IVD) cells experience a broad range of physicochemical stimuli under physiologic conditions, including alterations in their osmotic environment. At present, the molecular mechanisms underlying osmotic regulation in IVD cells are poorly understood. This study aims to screen genes affected by changes in osmotic pressure in cells of subjects aged 29 to 63 years old, with top-scoring pair (TSP) method. Gene expression data set GSE1648 was downloaded from Gene Expression Omnibus database, including four hyper-osmotic stimuli samples, four iso-osmotic stimuli samples, and three hypo-osmotic stimuli samples. A novel, simple method, referred to as the TSP, was used in this study. Through this method, there was no need to perform data normalization and transformation before data analysis. A total of five pairs of genes ((CYP2A6, FNTB), (PRPF8, TARDBP), (RPS5, OAZ1), (SLC25A3, NPM1) and (CBX3, SRSF9)) were selected based on the TSP method. We inferred that all these genes might play important roles in response to osmotic stimuli and age in IVD cells. Additionally, hyper-osmotic and iso-osmotic stimuli conditions were adverse factors for IVD cells. We anticipate that our results will provide new thoughts and methods for the study of IVD disease.

  10. Quantification of osmotic water transport in vivo using fluorescent albumin.

    Science.gov (United States)

    Morelle, Johann; Sow, Amadou; Vertommen, Didier; Jamar, François; Rippe, Bengt; Devuyst, Olivier

    2014-10-15

    Osmotic water transport across the peritoneal membrane is applied during peritoneal dialysis to remove the excess water accumulated in patients with end-stage renal disease. The discovery of aquaporin water channels and the generation of transgenic animals have stressed the need for novel and accurate methods to unravel molecular mechanisms of water permeability in vivo. Here, we describe the use of fluorescently labeled albumin as a reliable indicator of osmotic water transport across the peritoneal membrane in a well-established mouse model of peritoneal dialysis. After detailed evaluation of intraperitoneal tracer mass kinetics, the technique was validated against direct volumetry, considered as the gold standard. The pH-insensitive dye Alexa Fluor 555-albumin was applied to quantify osmotic water transport across the mouse peritoneal membrane resulting from modulating dialysate osmolality and genetic silencing of the water channel aquaporin-1 (AQP1). Quantification of osmotic water transport using Alexa Fluor 555-albumin closely correlated with direct volumetry and with estimations based on radioiodinated ((125)I) serum albumin (RISA). The low intraperitoneal pressure probably accounts for the negligible disappearance of the tracer from the peritoneal cavity in this model. Taken together, these data demonstrate the appropriateness of pH-insensitive Alexa Fluor 555-albumin as a practical and reliable intraperitoneal volume tracer to quantify osmotic water transport in vivo. Copyright © 2014 the American Physiological Society.

  11. Changes of hydrogen peroxide and radical-scavenging activity of raspberry during osmotic, convective, and freeze-drying.

    Science.gov (United States)

    Novaković, Miroslav M; Stevanović, Snežana M; Gorjanović, Stanislava Ž; Jovanovic, Predrag M; Tešević, Vele V; Janković, Miodrag A; Sužnjević, Desanka Ž

    2011-05-01

    This study was conducted to investigate the influence of different drying treatments on antioxidant (AO) activity and phenolic content of raspberry (Rubus idaeus), cultivar Willamette. Whole raspberry fruits were dried convectively (air-drying), osmotically, and freeze-dried. Acetone-water extracts of fresh and dried raspberries were assessed for total phenolic content by standard Folin-Ciocalteau method. Two AO assays were applied, a recently developed direct current (DC) polarographic assay based on decrease of anodic oxidation current of hydrogen peroxide and widely used radical scavenge against the 1,1-diphenyl-2-picrylhydrazyl (DPPH). Strong correlation has been obtained between both AO assays and total phenolic content. In addition, some individual phenolic compounds present in raspberry have been assessed using DPPH and DC polarographic assay. Comparison and evaluation of drying methods has been based on preservation of AO activity and total phenolic content. Obtained results confirmed superiority of freeze-drying; convective drying caused slight changes while osmotic dehydration showed a significant decrease of phenolic compounds and AO activity. © 2011 Institute of Food Technologists®

  12. Fragile X and autism: Intertwined at the molecular level leading to targeted treatments

    Directory of Open Access Journals (Sweden)

    Hagerman Randi

    2010-09-01

    Full Text Available Abstract Fragile X syndrome (FXS is caused by an expanded CGG repeat (> 200 repeats in the 5' untranslated portion of the fragile mental retardation 1 gene (FMR1, leading to deficiency or absence of the FMR1 protein (FMRP. FMRP is an RNA carrier protein that controls the translation of several other genes that regulate synaptic development and plasticity. Autism occurs in approximately 30% of FXS cases, and pervasive developmental disorder, not otherwise specified (PDD-NOS occurs in an additional 30% of cases. Premutation repeat expansions (55 to 200 CGG repeats may also give rise to autism spectrum disorders (ASD, including both autism and PDD-NOS, through a different molecular mechanism that involves a direct toxic effect of the expanded CGG repeat FMR1 mRNA. RNA toxicity can also lead to aging effects including tremor, ataxia and cognitive decline, termed fragile X-associated tremor ataxia syndrome (FXTAS, in premutation carriers in late life. In studies of mice bearing premutation expansions, there is evidence of early postnatal neuronal cell toxicity, presenting as reduced cell longevity, decreased dendritic arborization and altered synaptic morphology. There is also evidence of mitochondrial dysfunction in premutation carriers. Many of the problems with cellular dysregulation in both premutation and full mutation neurons also parallel the cellular abnormalities that have been documented in autism without fragile X mutations. Research regarding dysregulation of neurotransmitter systems in FXS, including the metabotropic glutamate receptor (mGluR1/5 pathway and γ aminobutyric acid (GABAA pathways, have led to new targeted treatments for FXS. Preliminary evidence suggests that these new targeted treatments will also be beneficial in non-fragile X forms of autism.

  13. Osmotic and Heat Stress Effects on Segmentation.

    Directory of Open Access Journals (Sweden)

    Julian Weiss

    Full Text Available During vertebrate embryonic development, early skin, muscle, and bone progenitor populations organize into segments known as somites. Defects in this conserved process of segmentation lead to skeletal and muscular deformities, such as congenital scoliosis, a curvature of the spine caused by vertebral defects. Environmental stresses such as hypoxia or heat shock produce segmentation defects, and significantly increase the penetrance and severity of vertebral defects in genetically susceptible individuals. Here we show that a brief exposure to a high osmolarity solution causes reproducible segmentation defects in developing zebrafish (Danio rerio embryos. Both osmotic shock and heat shock produce border defects in a dose-dependent manner, with an increase in both frequency and severity of defects. We also show that osmotic treatment has a delayed effect on somite development, similar to that observed in heat shocked embryos. Our results establish osmotic shock as an alternate experimental model for stress, affecting segmentation in a manner comparable to other known environmental stressors. The similar effects of these two distinct environmental stressors support a model in which a variety of cellular stresses act through a related response pathway that leads to disturbances in the segmentation process.

  14. Usng subjective percentiles and test data for estimating fragility functions

    International Nuclear Information System (INIS)

    George, L.L.; Mensing, R.W.

    1981-01-01

    Fragility functions are cumulative distribution functions (cdfs) of strengths at failure. They are needed for reliability analyses of systems such as power generation and transmission systems. Subjective opinions supplement sparse test data for estimating fragility functions. Often the opinions are opinions on the percentiles of the fragility function. Subjective percentiles are likely to be less biased than opinions on parameters of cdfs. Solutions to several problems in the estimation of fragility functions are found for subjective percentiles and test data. How subjective percentiles should be used to estimate subjective fragility functions, how subjective percentiles should be combined with test data, how fragility functions for several failure modes should be combined into a composite fragility function, and how inherent randomness and uncertainty due to lack of knowledge should be represented are considered. Subjective percentiles are treated as independent estimates of percentiles. The following are derived: least-squares parameter estimators for normal and lognormal cdfs, based on subjective percentiles (the method is applicable to any invertible cdf); a composite fragility function for combining several failure modes; estimators of variation within and between groups of experts for nonidentically distributed subjective percentiles; weighted least-squares estimators when subjective percentiles have higher variation at higher percents; and weighted least-squares and Bayes parameter estimators based on combining subjective percentiles and test data. 4 figures, 2 tables

  15. ThNAC13, a NAC Transcription Factor from Tamarix hispida, Confers Salt and Osmotic Stress Tolerance to Transgenic Tamarix and Arabidopsis

    Science.gov (United States)

    Wang, Liuqiang; Li, Zhen; Lu, Mengzhu; Wang, Yucheng

    2017-01-01

    NAC (NAM, ATAF1/2, and CUC2) proteins play critical roles in many plant biological processes and environmental stress. However, NAC proteins from Tamarix hispida have not been functionally characterized. Here, we studied a NAC gene from T. hispida, ThNAC13, in response to salt and osmotic stresses. ThNAC13 is a nuclear protein with a C-terminal transactivation domain. ThNAC13 can bind to NAC recognized sites and calmodulin-binding NAC (CBNAC) binding element. Overexpression of ThNAC13 in Arabidopsis improved seed germination rate and increased root growth and fresh weight gain under salt or osmotic stress. Transgenic T. hispida plants transiently overexpressing ThNAC13 and with RNAi-silenced ThNAC13 were generated for gain- and loss-of-function experiments. Following exposure to salt or osmotic stress, overexpression of ThNAC13 induced superoxide dismutase (SOD) and peroxidase (POD) activities, chlorophyll and proline contents; decreased the reactive oxygen species (ROS) and malondialdehyde levels; and reduced electrolyte leakage rates in both transgenic Tamarix and Arabidopsis plants. In contrast, RNAi-silenced ThNAC13 showed the opposite results in transgenic Tamarix. Furthermore, ThNAC13 induced the expression of SODs and PODs in transgenic Arabidopsis. These results suggest that ThNAC13 improves salt and osmotic tolerance by enhancing the ROS-scavenging capability and adjusting osmotic potential. PMID:28491072

  16. ThNAC13, a NAC Transcription Factor from Tamarix hispida, Confers Salt and Osmotic Stress Tolerance to Transgenic Tamarix and Arabidopsis

    Directory of Open Access Journals (Sweden)

    Mengzhu Lu

    2017-04-01

    Full Text Available NAC (NAM, ATAF1/2, and CUC2 proteins play critical roles in many plant biological processes and environmental stress. However, NAC proteins from Tamarix hispida have not been functionally characterized. Here, we studied a NAC gene from T. hispida, ThNAC13, in response to salt and osmotic stresses. ThNAC13 is a nuclear protein with a C-terminal transactivation domain. ThNAC13 can bind to NAC recognized sites and calmodulin-binding NAC (CBNAC binding element. Overexpression of ThNAC13 in Arabidopsis improved seed germination rate and increased root growth and fresh weight gain under salt or osmotic stress. Transgenic T. hispida plants transiently overexpressing ThNAC13 and with RNAi-silenced ThNAC13 were generated for gain- and loss-of-function experiments. Following exposure to salt or osmotic stress, overexpression of ThNAC13 induced superoxide dismutase (SOD and peroxidase (POD activities, chlorophyll and proline contents; decreased the reactive oxygen species (ROS and malondialdehyde levels; and reduced electrolyte leakage rates in both transgenic Tamarix and Arabidopsis plants. In contrast, RNAi-silenced ThNAC13 showed the opposite results in transgenic Tamarix. Furthermore, ThNAC13 induced the expression of SODs and PODs in transgenic Arabidopsis. These results suggest that ThNAC13 improves salt and osmotic tolerance by enhancing the ROS-scavenging capability and adjusting osmotic potential.

  17. Dependence of osmotic pressure on solution properties

    International Nuclear Information System (INIS)

    Fritz, S.J.

    1978-01-01

    Hydrostatic pressure, temperature, salt concentration, and the chemical composition of the salt are parameters affecting solution properties. Pressure and temperature have little effect on osmosis, but osmotic pressure variations due to type of dissolved salt may be significant, especially at high concentrations. For a given salt solution, concentration variations cause large differences in osmotic pressure. A representative difference in concentration across a clay layer in a relatively shallow groundwater system might be 100 to 1,000 ppm. When expressed as ppm NaCl, this difference could cause a head difference of 0.8 to 8 meters of water if one of the rock bodies were closed to fluid escape

  18. Molecular characterization of X chromosome fragility in idiopathic ...

    African Journals Online (AJOL)

    Heba Alla Hosny Omar

    2015-11-23

    Nov 23, 2015 ... Frequency of fragile X syndrome among male siblings and relatives of mentally retarded patients ... hence the wide clinical spectrum of disorders caused by this ... fragile X syndrome, autism and other less well-characterized.

  19. Trio Fragile / Olga Kaljundi

    Index Scriptorium Estoniae

    Kaljundi, Olga, 1941-2001

    1998-01-01

    Tallinna Vene Draamateatri galeriis esinenud trupi "Trio Fragile" vernissaazhist. Trio loomingust ja osalejatest : kahe muusiku seltskonnas esineb ka 1984.a. Kunstiülikooli lõpetanud kunstnik Tõnu Talve.

  20. Attentional Set-Shifting in Fragile X Syndrome

    Science.gov (United States)

    Van der Molen, M. J. W.; Van der Molen, M. W.; Ridderinkhof, K. R.; Hamel, B. C. J.; Curfs, L. M. G.; Ramakers, G. J. A.

    2012-01-01

    The ability to flexibly adapt to the changing demands of the environment is often reported as a core deficit in fragile X syndrome (FXS). However, the cognitive processes that determine this attentional set-shifting deficit remain elusive. The present study investigated attentional set-shifting ability in fragile X syndrome males with the…

  1. Influence of osmotic pressure on the growth of three species of the genus Zoophthora

    Directory of Open Access Journals (Sweden)

    Jerzy Piątkowski

    2013-12-01

    Full Text Available Strains accomodated in the genus Zoophthora are very sensitive to osmotic value of their habitat. Hipertonical molarity of buffers and NaCl decreases the growth, but this effect strongly depends on the species tested and on the kind of buffer. In 0.66% phtalan buffer the growth of Z. lanceolata is completely stopped whereas Z. psyllae and Z. aphrophora is inhibited only in 50% comparing to the control.

  2. Osmotic generation of 'anomalous' fluid pressures in geological environments

    Science.gov (United States)

    Neuzii, C.E.

    2000-01-01

    Osmotic pressures are generated by differences in chemical potential of a solution across a membrane. But whether osmosis can have a significant effect on the pressure of fluids in geological environments has been controversial, because the membrane properties of geological media are poorly understood. 'Anomalous' pressures - large departures from hydrostatic pressure that are not explicable in terms of topographic or fluid-density effects are widely found in geological settings, and are commonly considered to result from processes that alter the pore or fluid volume, which in turn implies crustal changes happening at a rate too slow to observe directly. Yet if osmosis can explain some anomalies, there is no need to invoke such dynamic geological processes in those cases. Here I report results of a nine- year in situ measurement of fluid pressures and solute concentrations in shale that are consistent with the generation of large (up to 20 MPa) osmotic-pressure anomalies which could persist for tens of millions of years. Osmotic pressures of this magnitude and duration can explain many of the pressure anomalies observed in geological settings. The require, however, small shale porosity and large contrasts in the amount of dissolved solids in the pore waters - criteria that may help to distinguish between osmotic and crystal-dynamic origins of anomalous pressures.

  3. Dehydration and osmotic adjustment in apple stem tissue during winter as it relates to the frost resistance of buds.

    Science.gov (United States)

    Pramsohler, Manuel; Neuner, Gilbert

    2013-08-01

    In deciduous trees, measurement of stem water potential can be difficult during the leafless period in winter. By using thermocouple psychrometry, osmotic water potentials (Ψo; actual Ψo: Ψo(act); Ψo at full saturation: Ψo(sat)) of expressed sap of bark and bud tissue were measured in order to test if the severity of winter desiccation in apple stems could be sufficiently assessed with Ψo. Water potentials were related to frost resistance and freezing behaviour of buds. The determination of Ψo reliably allowed winter desiccation and osmotic adjustments in apple stem tissue to be assessed. In winter in bark tissue, a pronounced decrease in Ψo(act) and Ψo(sat) was found. Decreased Ψo(sat) indicates active osmotic adjustment in the bark as observed earlier in the leaves of evergreen woody plants. In terminal bud meristems, no significant osmotic adjustments occurred and dehydration during winter was much less. Osmotic water potentials, Ψo(act) and Ψo(sat), of bud tissue were always less negative than in the bark. To prevent water movement and dehydration of the bud tissue via this osmotic gradient, it must be compensated for either by a sufficiently high turgor pressure (Ψp) in bark tissue or by the isolation of the bud tissue from the bark during midwinter. During freezing of apple buds, freeze dehydration and extra-organ freezing could be demonstrated by significantly reduced Ψo(act) values of bud meristems that had been excised in the frozen state. Infrared video thermography was used to monitor freezing patterns in apple twigs. During extracellular freezing of intact and longitudinally dissected stems, infrared differential thermal analysis (IDTA) images showed that the bud meristem remains ice free. Even if cooled to temperatures below the frost-killing temperature, no freezing event could be detected in bud meristems during winter. In contrast, after bud break, terminal buds showed a second freezing at the frost-killing temperature that indicates

  4. OSMOTIC DEHYDRATION KINETICS OF GUAVAS IN MALTOSE SOLUTIONS WITH CALCIUM SALT*

    Directory of Open Access Journals (Sweden)

    S. DI S. MASTRANTONIO

    2009-03-01

    Full Text Available

    The osmotic dehydration kinetics of guavas in maltose solutions at 40 and 60ºBrix, with addition of 0, 0.6 and 1.2% of calcium lactate was studied in this paper and the final product quality was evaluated. The experiments were carried out up to 60 hours and samples were taken for analysis at different times to evaluate guavas weight reduction, water loss and sugar gain and to characterize the product according to its texture and color. After 24 hours of process the mass transfer of water and sugar between the osmotic solution and the fruit was negligible, showing that process equilibrium was reached. The increase of sugar concentration in the osmotic solution showed strong influence on the dehydration process, increasing the water loss and reducing sugar gain. The presence of calcium ions in the osmotic solution also influenced the kinetics of mass transfer and showed a strong influence on fruit texture. Higher values of stress and strain at failure were obtained when calcium lactate was employed. The effect of the different osmotic treatments on the color parameters was also investigated and significant changes were observed in the values of chroma C* and hue H* due to sugar concentration and calcium addition.

    KEYWORDS: Osmotic dehydration; kinetics; guava; maltose; calcium lactate.

  5. Improved Iris Recognition through Fusion of Hamming Distance and Fragile Bit Distance.

    Science.gov (United States)

    Hollingsworth, Karen P; Bowyer, Kevin W; Flynn, Patrick J

    2011-12-01

    The most common iris biometric algorithm represents the texture of an iris using a binary iris code. Not all bits in an iris code are equally consistent. A bit is deemed fragile if its value changes across iris codes created from different images of the same iris. Previous research has shown that iris recognition performance can be improved by masking these fragile bits. Rather than ignoring fragile bits completely, we consider what beneficial information can be obtained from the fragile bits. We find that the locations of fragile bits tend to be consistent across different iris codes of the same eye. We present a metric, called the fragile bit distance, which quantitatively measures the coincidence of the fragile bit patterns in two iris codes. We find that score fusion of fragile bit distance and Hamming distance works better for recognition than Hamming distance alone. To our knowledge, this is the first and only work to use the coincidence of fragile bit locations to improve the accuracy of matches.

  6. High functioning male with fragile X syndrome and fragile X-associated tremor/ataxia syndrome.

    Science.gov (United States)

    Basuta, Kirin; Schneider, Andrea; Gane, Louise; Polussa, Jonathan; Woodruff, Bryan; Pretto, Dalyir; Hagerman, Randi; Tassone, Flora

    2015-09-01

    Fragile X syndrome (FXS) affects individuals with more than 200 CGG repeats (full mutation) in the fragile X mental retardation 1 (FMR1) gene. Those born with FXS experience cognitive and social impairments, developmental delays, and some features of autism spectrum disorders. Carriers of a premutation (55-200 CGG repeats) are generally not severely affected early in life; however, are at high risk of developing the late onset neurodegenerative disorder, Fragile X-associated Tremor/Ataxia Syndrome (FXTAS), or Fragile X-associated Primary Ovarian Insufficiency (FXPOI), and may have other medical conditions such as developmental delay, autism spectrum disorders, hypertension, anxiety, and immune-mediated disorders. Here we present a case of a 58-year-old man with a borderline IQ, average memory skills, and executive function deficits. He met criteria for multiple psychiatric diagnoses and presented with tremor and ataxia, meeting criteria for FXTAS. Molecular testing unveiled a completely unmethylated FMR1 full mutation in peripheral blood mononucleated cells with elevated FMR1 mRNA and premutation alleles of different sizes in two other tissues (primary fibroblasts and sperm), indicating the presence of allele instability based on both inter- and intra-tissue mosaicism. The observation of FXTAS in this case of a full mutation mosaic man suggests that the pathogenic mechanism underlying this disorder is not observed exclusively in premutation carriers as it was originally thought. The concomitant presence of features of FXS and late onset neurological deterioration with probable FXTAS likely result from a combined molecular pathology of elevated FMR1 mRNA levels, a molecular hallmark of FXTAS and low FMRP expression that leads to FXS. © 2015 Wiley Periodicals, Inc.

  7. Magnetic resonance studies on the brain edema by the administration of the osmotic agents; Special references to the relaxation times

    Energy Technology Data Exchange (ETDEWEB)

    Niino, Masaki; Asakura, Tetsuhiko; Nakamura, Katsumi; Yatsushiro, Kazutaka; Kadota, Koki (Kagoshima Univ. (Japan). Faculty of Medicine); Sasahira, Masahiro; Fujimoto, Toshiro; Shimooki, Susumu

    1990-03-01

    Changes of proton relaxation times (T{sub 1} and T{sub 2}) and MR imaging of the brain edema by the administration of the osmotic agents (mannitol or glycerol) were studied. Subjects were 11 patients who were composed of 4 gliomas, 2 metastatic brain tumors, 2 meningiomas, 2 hypertensive intracerebral hematomas, and a C-P angle tumor. 20% mannitol or 10% glycerol 550 ml was rapidly injected intravenously. Scanning was done before injection, just after injection, and post injection until 2 hours with passing times. We regarded the peritumoral or perihemorrahgical low density area on the CT scan as the edema, and then, relaxation times of the edema was obtained from the ROI of the calculated images corresponding to the surrounding low density area on the CT scan. The results were as follows. (1) In general, relaxation times of the edema showed a tendency to decrease after injection of the osmotic agents. Normal white matter, in the same way, showed the decreasing tendency, but the degree of the decreasing was more clearly in the edematous areas than in the white matter. (2) The changes of relaxation times did not show a uniform pattern. In most cases, relaxation times decreased just after injection. But in a few cases, relaxation times increased just after injection, transiently. In some cases, decreased relaxation times continued more than 2 hours, in the other cases, relaxation times increased at 2 hours. (3) The changes of relaxation times thought to be varied by some factors, that is --kinds of the lesions causing edema, degree of malignancy of the lesions, or phase of edema (acute or chronic) etc. (4) Osmotic agents were supposed to dehydrate the edematous lesions. In the current MR systems, there are considerably large standard deviations and inequality in the magnetic field, therefore, further investigations should be done moreover. (author).

  8. Fragility correlates thermodynamic and kinetic properties of glass forming liquids

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, C.Narayana [Maharani’s Science College for Women, Bangalore 560001 (India); Viswanatha, R.; Chethana, B.K. [Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012 (India); Gowda, V.C.Veeranna [Government First Grade College, Jayanagara, Bangalore 560070 (India); Rao, K.J., E-mail: kalyajrao@yahoo.co.in [Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012 (India)

    2015-03-15

    Graphical abstract: The suggested new fragility parameter correlates viscosity and configurational entropy. - Highlights: • A new fragility function, F=ΔT/ΔC{sub p}×C{sub p}{sup l}/T{sub g} has been proposed. • A three parameter viscosity function using the new F reproduces Angell fragility plot. • A new ΔC{sub p} function is derived which directly relates Adam–Gibbs function with the fragility based viscosity function. - Abstract: In our earlier communication we proposed a simple fragility determining function, ([NBO]/V{sub m}{sup 3}T{sub g}), which we have now used to analyze several glass systems using available thermal data. A comparison with similar fragility determining function, ΔC{sub p}/C{sub p}{sup l}, introduced by Chryssikos et al. in their investigation of lithium borate glasses has also been performed and found to be more convenient quantity for discussing fragilities. We now propose a new function which uses both ΔC{sub p} and ΔT and which gives a numerical fragility parameter, F whose value lies between 0 and 1 for glass forming liquids. F can be calculated through the use of measured thermal parameters ΔC{sub p}, C{sub p}{sup l}, T{sub g} and T{sub m}. Use of the new fragility values in reduced viscosity equation reproduces the whole range of viscosity curves of the Angell plot. The reduced viscosity equation can be directly compared with the Adam–Gibbs viscosity equation and a heat capacity function can be formulated which reproduces satisfactorily the ΔC{sub p} versus ln(T{sub r}) curves and hence the configurational entropy.

  9. Osmotic dehydration of Braeburn variety apples in the production of sustainable food products

    Science.gov (United States)

    Ciurzyńska, Agnieszka; Cichowska, Joanna; Kowalska, Hanna; Czajkowska, Kinga; Lenart, Andrzej

    2018-01-01

    The aim of this work was to investigate the effects of osmotic dehydration conditions on the properties of osmotically pre-treated dried apples. The scope of research included analysing the most important mass exchange coefficients, i.e. water loss, solid gain, reduced water content and water activity, as well as colour changes of the obtained dried product. In the study, apples were osmotically dehydrated in one of two 60% solutions: sucrose or sucrose with an addition of chokeberry juice concentrate, for 30 and 120 min, in temperatures of 40 and 60°C. Ultrasound was also used during the first 30 min of the dehydration process. After osmotic pre-treatment, apples were subjected to innovative convective drying with the puffing effect, and to freeze-drying. Temperature and dehydration time increased the effectiveness of mass exchange during osmotic dehydration. The addition of chokeberry juice concentrate to standard sucrose solution and the use of ultrasound did not change the value of solid gain and reduced water content. Water activity of the dried apple tissue was not significantly changed after osmotic dehydration, while changes in colour were significant.

  10. Developing empirical collapse fragility functions for global building types

    Science.gov (United States)

    Jaiswal, K.; Wald, D.; D'Ayala, D.

    2011-01-01

    Building collapse is the dominant cause of casualties during earthquakes. In order to better predict human fatalities, the U.S. Geological Survey’s Prompt Assessment of Global Earthquakes for Response (PAGER) program requires collapse fragility functions for global building types. The collapse fragility is expressed as the probability of collapse at discrete levels of the input hazard defined in terms of macroseismic intensity. This article provides a simple procedure for quantifying collapse fragility using vulnerability criteria based on the European Macroseismic Scale (1998) for selected European building types. In addition, the collapse fragility functions are developed for global building types by fitting the beta distribution to the multiple experts’ estimates for the same building type (obtained from EERI’s World Housing Encyclopedia (WHE)-PAGER survey). Finally, using the collapse probability distributions at each shaking intensity level as a prior and field-based collapse-rate observations as likelihood, it is possible to update the collapse fragility functions for global building types using the Bayesian procedure.

  11. A review on controlled porosity osmotic pump tablets and its evaluation

    Directory of Open Access Journals (Sweden)

    Chinmaya Keshari Sahoo

    2015-12-01

    Full Text Available Conventional drug delivery system provides an immediate release of drug which does not control the release of the drug and does not maintain effective concentration at target site for a longer period of time. Hence to avoid the shortcomings there is development of various controlled drug delivery systems. Among these osmotic drug delivery system (ODDS utilizes the principle of osmotic pressure and delivers drug dose in an optimized manner to maintain drug concentration within the therapeutic window and minimizes toxic effects. ODDS releases drug at a controlled rate that is independent of the pH and thermodynamics of dissolution medium. The release of drug from ODDS follows zero order kinetics. The release of drug from osmotic system depends upon various formulation factors such as solubility, osmotic pressure of the core components, size of the delivery orifice and nature of the rate controlling membrane. Controlled porosity osmotic pump (CPOP contains drug, osmogens, excipients in core and a coating of semipermeable membrane with water soluble additives. In CPOP water soluble additives dissolve after coming in contact with water, resulting in an in situ formation of a microporous membrane. The present study gives an idea about osmosis, CPOP, components of CPOP and its evaluation.

  12. Cystic fibrosis airway secretions exhibit mucin hyperconcentration and increased osmotic pressure

    Science.gov (United States)

    Henderson, Ashley G.; Ehre, Camille; Button, Brian; Abdullah, Lubna H.; Cai, Li-Heng; Leigh, Margaret W.; DeMaria, Genevieve C.; Matsui, Hiro; Donaldson, Scott H.; Davis, C. William; Sheehan, John K.; Boucher, Richard C.; Kesimer, Mehmet

    2014-01-01

    The pathogenesis of mucoinfective lung disease in cystic fibrosis (CF) patients likely involves poor mucus clearance. A recent model of mucus clearance predicts that mucus flow depends on the relative mucin concentration of the mucus layer compared with that of the periciliary layer; however, mucin concentrations have been difficult to measure in CF secretions. Here, we have shown that the concentration of mucin in CF sputum is low when measured by immunologically based techniques, and mass spectrometric analyses of CF mucins revealed mucin cleavage at antibody recognition sites. Using physical size exclusion chromatography/differential refractometry (SEC/dRI) techniques, we determined that mucin concentrations in CF secretions were higher than those in normal secretions. Measurements of partial osmotic pressures revealed that the partial osmotic pressure of CF sputum and the retained mucus in excised CF lungs were substantially greater than the partial osmotic pressure of normal secretions. Our data reveal that mucin concentration cannot be accurately measured immunologically in proteolytically active CF secretions; mucins are hyperconcentrated in CF secretions; and CF secretion osmotic pressures predict mucus layer–dependent osmotic compression of the periciliary liquid layer in CF lungs. Consequently, mucin hypersecretion likely produces mucus stasis, which contributes to key infectious and inflammatory components of CF lung disease. PMID:24892808

  13. Treatment of Fragile X Syndrome with a Neuroactive Steroid

    Science.gov (United States)

    2013-08-01

    Fulks JL, O’Bryhim BE et al (2010) Dopamine release and uptake impairments and behavioral alterations observed in mice that model fragile x mental...D2 dopamine receptor agonist. J Cogn Neurosci 4(1):58–68 Luo Y, Shan G et al (2010) Fragile x mental retardation protein regulates proliferation and...AD_________________ Award Number: W81XWH-11-1-0626 TITLE: Treatment of Fragile X Syndrome with a

  14. Nuclear Power Plant Mechanical Component Flooding Fragility Experiments Status

    Energy Technology Data Exchange (ETDEWEB)

    Pope, C. L. [Idaho State Univ., Pocatello, ID (United States); Savage, B. [Idaho State Univ., Pocatello, ID (United States); Johnson, B. [Idaho State Univ., Pocatello, ID (United States); Muchmore, C. [Idaho State Univ., Pocatello, ID (United States); Nichols, L. [Idaho State Univ., Pocatello, ID (United States); Roberts, G. [Idaho State Univ., Pocatello, ID (United States); Ryan, E. [Idaho State Univ., Pocatello, ID (United States); Suresh, S. [Idaho State Univ., Pocatello, ID (United States); Tahhan, A. [Idaho State Univ., Pocatello, ID (United States); Tuladhar, R. [Idaho State Univ., Pocatello, ID (United States); Wells, A. [Idaho State Univ., Pocatello, ID (United States); Smith, C. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-07-24

    This report describes progress on Nuclear Power Plant mechanical component flooding fragility experiments and supporting research. The progress includes execution of full scale fragility experiments using hollow-core doors, design of improvements to the Portal Evaluation Tank, equipment procurement and initial installation of PET improvements, designation of experiments exploiting the improved PET capabilities, fragility mathematical model development, Smoothed Particle Hydrodynamic simulations, wave impact simulation device research, and pipe rupture mechanics research.

  15. Seismic fragility of nuclear power plant components. Phase I

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.

    1986-06-01

    As part of the Component Fragility Research Program, sponsored by the US Nuclear Regulatory Commission, BNL is involved in establishing seismic fragility levels for various nuclear power plant equipment by identifying, collecting and analyzing existing test data from various sources. In Phase I of this program, BNL has reviewed approximately seventy test reports to collect fragility or high level test data for switchgears, motor control centers and similar electrical cabinets, valve actuators and numerous electrical devices of various manufacturers and models. This report provides an assessment and evaluation of the data collected in Phase I. The fragility data for medium voltage and low voltage switchgears and motor control centers are analyzed using the test response spectra (TRS) as a measure of the fragility level. The analysis reveals that fragility levels can best be described by a group of TRS curves corresponding to various failure modes. The lower-bound curve indicates the initiation of malfunctioning or structural damage; whereas, the upper-bound curve corresponds to overall failure of the equipment based on known failure modes. High level test data for some components are included in the report. These data indicate that some components are inherently strong and do not exhibit any failure mode even when tested at the vibration limit of a shake table. The common failure modes are identified in the report. The fragility levels determined in this report have been compared with those used in the PRA and Seismic Margin Studies. It appears that the BNL data better correlate with the HCLPF (High Confidence of a Low Probability of Failure) level used in Seismic Margin Studies and can improve this level as high as 60% for certain applications. Specific recommendations are provided for proper application of BNL fragility data to other studies

  16. Hydration induced material transfer in membranes of osmotic pump tablets measured by synchrotron radiation based FTIR.

    Science.gov (United States)

    Wu, Li; Yin, Xianzhen; Guo, Zhen; Tong, Yajun; Feng, Jing; York, Peter; Xiao, Tiqiao; Chen, Min; Gu, Jingkai; Zhang, Jiwen

    2016-03-10

    Osmotic pump tablets are reliable oral controlled drug delivery systems based on their semipermeable membrane coating. This research used synchrotron radiation-based Fourier transform infrared (SR-FTIR) microspectroscopy and imaging to investigate the hydration induced material transfer in the membranes of osmotic pump tablets. SR-FTIR was applied to record and map the chemical information of a micro-region of the membranes, composed of cellulose acetate (CA, as the water insoluble matrix) and polyethylene glycol (PEG, as the soluble pore forming agent and plasticizing agent). The microstructure and chemical change of membranes hydrated for 0, 5, 10 and 30min were measured using SR-FTIR, combined with scanning electronic microscopy and atom force microscopy. The SR-FTIR microspectroscopy results indicated that there was a major change at the absorption range of 2700-3100cm(-1) in the membranes after different periods of hydration time. The absorption bands at 2870-2880cm(-1) and 2950-2960cm(-1) were assigned to represent CA and PEG, respectively. The chemical group signal distribution illustrated by the ratio of PEG to CA demonstrated that the trigger of drug release in the preliminary stage was due to the rapid transfer of PEG into liquid medium with a sharp decrease of PEG in the membranes. The SR-FTIR mapping results have demonstrated the hydration induced material transfer in the membranes of osmotic pump tablets and enabled reassessment of the drug release mechanism of membrane controlled osmotic pump systems. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Osmotic Effects in Sludge Dewatering

    DEFF Research Database (Denmark)

    Keiding, Kristian; Rasmussen, Michael R.

    2003-01-01

    A model of filtration dewatering is presented. The model is based on the d’Arcy flow equation in which the resistance to filtration is described by the Corzeny–Carman equation and the driving force is the difference between the external pressure and the osmotic pressure of the filter cake. It has...

  18. Recent development in osmotic dehydration of fruit and vegetables: a review.

    Science.gov (United States)

    Chandra, Suresh; Kumari, Durvesh

    2015-01-01

    Osmotic dehydration of fruits and vegetables is achieved by placing the solid/semi solid, whole or in pieces, in a hypertonic solution (sugar and/or salt) with a simultaneous counter diffusion of solutes from the osmotic solution into the tissues. Osmotic dehydration is recommended as a processing method to obtain better quality of food products. Partial dehydration allows structural, nutritional, sensory, and other functional properties of the raw material to be modified. However, the food industry uptake of osmotic dehydration of foods has not been extensive as expected due to the poor understanding of the counter current flow phenomena associated with it. However, these flows are in a dynamic equilibrium with each other and significantly influence the final product in terms of preservation, nutrition, and organoleptic properties. The demand of healthy, natural, nutritious, and tasty processed food products continuously increases, not only for finished products, but also for ingredient to be included in complex foods such as ice cream, cereals, dairy, confectionaries, and bakery products.

  19. A cellulose synthase-like protein is required for osmotic stress tolerance in Arabidopsis

    KAUST Repository

    Zhu, Jianhua

    2010-04-16

    Osmotic stress imposed by soil salinity and drought stress significantly affects plant growth and development, but osmotic stress sensing and tolerance mechanisms are not well understood. Forward genetic screens using a root-bending assay have previously identified salt overly sensitive (sos) mutants of Arabidopsis that fall into five loci, SOS1 to SOS5. These loci are required for the regulation of ion homeostasis or cell expansion under salt stress, but do not play a major role in plant tolerance to the osmotic stress component of soil salinity or drought. Here we report an additional sos mutant, sos6-1, which defines a locus essential for osmotic stress tolerance. sos6-1 plants are hypersensitive to salt stress and osmotic stress imposed by mannitol or polyethylene glycol in culture media or by water deficit in the soil. SOS6 encodes a cellulose synthase-like protein, AtCSLD5. Only modest differences in cell wall chemical composition could be detected, but we found that sos6-1 mutant plants accumulate high levels of reactive oxygen species (ROS) under osmotic stress and are hypersensitive to the oxidative stress reagent methyl viologen. The results suggest that SOS6/AtCSLD5 is not required for normal plant growth and development but has a critical role in osmotic stress tolerance and this function likely involves its regulation of ROS under stress. © 2010 Blackwell Publishing Ltd.

  20. Cognitive Improvement of Attention and Inhibition in the Late Afternoon in Children With Attention-Deficit Hyperactivity Disorder (ADHD) Treated With Osmotic-Release Oral System Methylphenidate.

    Science.gov (United States)

    Slama, Hichem; Fery, Patrick; Verheulpen, Denis; Vanzeveren, Nathalie; Van Bogaert, Patrick

    2015-07-01

    Long-acting medications have been developed and approved for use in the treatment of attention-deficit hyperactivity disorder (ADHD). These compounds are intended to optimize and maintain symptoms control throughout the day. We tested prolonged effects of osmotic-release oral system methylphenidate on both attention and inhibition, in the late afternoon. A double-blind, randomized, placebo-controlled study was conducted in 36 boys (7-12 years) with ADHD and 40 typically developing children. The ADHD children received an individualized dose of placebo or osmotic-release oral system methylphenidate. They were tested about 8 hours after taking with 2 continuous performance tests (continuous performance test-X [CPT-X] and continuous performance test-AX [CPT-AX]) and a counting Stroop. A positive effect of osmotic-release oral system methylphenidate was present in CPT-AX with faster and less variable reaction times under osmotic-release oral system methylphenidate than under placebo, and no difference with typically developing children. In the counting Stroop, we found a decreased interference with osmotic-release oral system methylphenidate but no difference between children with ADHD under placebo and typically developing children. © The Author(s) 2014.

  1. Kerr black holes are not fragile

    Energy Technology Data Exchange (ETDEWEB)

    McInnes, Brett, E-mail: matmcinn@nus.edu.sg [Centro de Estudios Cientificos (CECs), Valdivia (Chile); National University of Singapore (Singapore)

    2012-04-21

    Certain AdS black holes are 'fragile', in the sense that, if they are deformed excessively, they become unstable to a fundamental non-perturbative stringy effect analogous to Schwinger pair-production [of branes]. Near-extremal topologically spherical AdS-Kerr black holes, which are natural candidates for string-theoretic models of the very rapidly rotating black holes that have actually been observed to exist, do represent a very drastic deformation of the AdS-Schwarzschild geometry. One therefore has strong reason to fear that these objects might be 'fragile', which in turn could mean that asymptotically flat rapidly rotating black holes might be fragile in string theory. Here we show that this does not happen: despite the severe deformation implied by near-extremal angular momenta, brane pair-production around topologically spherical AdS-Kerr-Newman black holes is always suppressed.

  2. The effect of osmotic pretreatment on the density of hot-air-dried carrot

    Directory of Open Access Journals (Sweden)

    J Soleimani

    2012-02-01

    Full Text Available Consumption of large amounts of fruits and vegetables throughout the world, have encouraged the development of various methods for their processing. Drying is considers as the most common method for preservation of vegetable and fruits. Although drying extend the shelf-life, it has various side effects on keeping quality of these foods; including decreasing of the color and texture quality as well as missing the flavor and nutritional values. These negative effects have increased the demand for the discovering the alternative drying methods and consequently for the production of fresh-like products. The aim of this study was to introduce and optimize the novel method for the drying of carrot as well as to develop and optimize the quality of osmo-air-dried carrots with special respect to the color, flavor, texture, rehydration properties, density and shriveling of the product. For this, the effect of osmotic pretreatment on the density of carrot slices was investigated, using 50% glucose syrup +5% salt at 40°C with 150 rpm, followed by complementary drying step. The result of treated group was compared with control samples which were dried only by hot-air-drier. The results showed that using osmotic pretreatment could increase the density through inhibition of the product's shrinkage. Meanwhile, in air-dried samples the density was decreased considerably and high shrinkage was also observed.

  3. Controlled porosity solubility modulated osmotic pump tablets of gliclazide.

    Science.gov (United States)

    Banerjee, Arti; Verma, P R P; Gore, Subhash

    2015-06-01

    A system that can deliver drug at a controlled rate is very important for the treatment of various chronic diseases such as diabetes, asthma, and heart disease. Poorly water-soluble drug with pH-dependent solubility such as gliclazide (GLZ) offers challenges in the controlled-release formulation because of low dissolution rate and poor bioavailability. Solid dispersion (SD) of GLZ consisted of hydroxypropyl cellulose (HPC-SSL) as a polymeric solubilizer was manufactured by hot melt extrusion (HME) technology. Then, controlled porosity osmotic pump (CPOP) tablet of gliclazide was designed to deliver drug in a controlled manner up to 16 h. The developed formulation was optimized for type and level of pore former and coating weight gain. The optimized formulation was found to exhibit zero order kinetics independent of pH and agitation speed but depends on osmotic pressure of dissolution media indicated that mechanism of drug release was osmotic pressure. The in vivo performance prediction of developed formulation using convolution approach revealed that the developed formulation was superior to the existing marketed extended-release formulation in terms of attaining steady state plasma levels and indicated adequate exposure in translating hypoglycemic response. The prototype solubilization method combined with controlled porosity osmotic pump based technique could provide a unique way to increase dissolution rate and bioavailability of many poorly water-soluble, narrow therapeutic index drugs used in diabetes, cardiovascular diseases, etc.

  4. The osmotic stress response of split influenza vaccine particles in an acidic environment.

    Science.gov (United States)

    Choi, Hyo-Jick; Kim, Min-Chul; Kang, Sang-Moo; Montemagno, Carlo D

    2014-12-01

    Oral influenza vaccine provides an efficient means of preventing seasonal and pandemic disease. In this work, the stability of envelope-type split influenza vaccine particles in acidic environments has been investigated. Owing to the fact that hyper-osmotic stress can significantly affect lipid assembly of vaccine, osmotic stress-induced morphological change of split vaccine particles, in conjunction with structural change of antigenic proteins, was investigated by the use of stopped-flow light scattering (SFLS), intrinsic fluorescence, transmission electron microscopy (TEM), and hemagglutination assay. Split vaccine particles were found to exhibit a step-wise morphological change in response to osmotic stress due to double-layered wall structure. The presence of hyper-osmotic stress in acidic medium (0.3 osmolarity, pH 2.0) induced a significant level of membrane perturbation as measured by SFLS and TEM, imposing more damage to antigenic proteins on vaccine envelope than can be caused by pH-induced conformational change at acidic iso-osmotic condition. Further supports were provided by the intrinsic fluorescence and hemagglutinin activity measurements. Thus, hyper-osmotic stress becomes an important factor for determining stability of split vaccine particles in acidic medium. These results are useful in better understanding the destabilizing mechanism of split influenza vaccine particles in gastric environment and in designing oral influenza vaccine formulations.

  5. The effects of osmotic stress on the structure and function of the cell nucleus.

    Science.gov (United States)

    Finan, John D; Guilak, Farshid

    2010-02-15

    Osmotic stress is a potent regulator of the normal function of cells that are exposed to osmotically active environments under physiologic or pathologic conditions. The ability of cells to alter gene expression and metabolic activity in response to changes in the osmotic environment provides an additional regulatory mechanism for a diverse array of tissues and organs in the human body. In addition to the activation of various osmotically- or volume-activated ion channels, osmotic stress may also act on the genome via a direct biophysical pathway. Changes in extracellular osmolality alter cell volume, and therefore, the concentration of intracellular macromolecules. In turn, intracellular macromolecule concentration is a key physical parameter affecting the spatial organization and pressurization of the nucleus. Hyper-osmotic stress shrinks the nucleus and causes it to assume a convoluted shape, whereas hypo-osmotic stress swells the nucleus to a size that is limited by stretch of the nuclear lamina and induces a smooth, round shape of the nucleus. These behaviors are consistent with a model of the nucleus as a charged core/shell structure pressurized by uneven partition of macromolecules between the nucleoplasm and the cytoplasm. These osmotically-induced alterations in the internal structure and arrangement of chromatin, as well as potential changes in the nuclear membrane and pores are hypothesized to influence gene transcription and/or nucleocytoplasmic transport. A further understanding of the biophysical and biochemical mechanisms involved in these processes would have important ramifications for a range of fields including differentiation, migration, mechanotransduction, DNA repair, and tumorigenesis. (c) 2009 Wiley-Liss, Inc.

  6. The osmotic second virial coefficient and the Gibbs-McMillan-Mayer framework

    DEFF Research Database (Denmark)

    Mollerup, J.M.; Breil, Martin Peter

    2009-01-01

    The osmotic second virial coefficient is a key parameter in light scattering, protein crystallisation. self-interaction chromatography, and osmometry. The interpretation of the osmotic second virial coefficient depends on the set of independent variables. This commonly includes the independent...... variables associated with the Kirkwood-Buff, the McMillan-Mayer, and the Lewis-Randall solution theories. In this paper we analyse the osmotic second virial coefficient using a Gibbs-McMillan-Mayer framework which is similar to the McMillan-Mayer framework with the exception that pressure rather than volume...... is an independent variable. A Taylor expansion is applied to the osmotic pressure of a solution where one of the solutes is a small molecule, a salt for instance, that equilibrates between the two phases. Other solutes are retained. Solvents are small molecules that equilibrate between the two phases...

  7. On equations for the total suction and its matric and osmotic components

    International Nuclear Information System (INIS)

    Dao, Vinh N.T.; Morris, Peter H.; Dux, Peter F.

    2008-01-01

    A clear fundamental understanding of suctions is crucial for the study of the behaviour of plastic cement mortar and concrete, including plastic shrinkage cracking. In this paper, the expression relating the change in free energy of the pore water with an isothermal change in pressure is first derived. Based upon definitions of suctions, it is then shown that total, matric, and osmotic suctions can all be expressed in the same thermodynamic form. The widely accepted, but not yet satisfactorily validated, assumption that the total suction comprises matric and osmotic components is then confirmed theoretically. The well-known Kelvin equation for matric suction, and Morse and van't Hoff equations for osmotic suction are subsequently derived from the corresponding thermodynamic equations. The applicability of latter two equations in evaluating the osmotic suctions of cement mortar and concrete is highlighted

  8. Expression profiling on soybean leaves reveals integration of ER- and osmotic-stress pathways

    Directory of Open Access Journals (Sweden)

    Dewey Ralph E

    2007-11-01

    Full Text Available Abstract Background Despite the potential of the endoplasmic reticulum (ER stress response to accommodate adaptive pathways, its integration with other environmental-induced responses is poorly understood in plants. We have previously demonstrated that the ER-stress sensor binding protein (BiP from soybean exhibits an unusual response to drought. The members of the soybean BiP gene family are differentially regulated by osmotic stress and soybean BiP confers tolerance to drought. While these results may reflect crosstalk between the osmotic and ER-stress signaling pathways, the lack of mutants, transcriptional response profiles to stresses and genome sequence information of this relevant crop has limited our attempts to identify integrated networks between osmotic and ER stress-induced adaptive responses. As a fundamental step towards this goal, we performed global expression profiling on soybean leaves exposed to polyethylene glycol treatment (osmotic stress or to ER stress inducers. Results The up-regulated stress-specific changes unmasked the major branches of the ER-stress response, which include enhancing protein folding and degradation in the ER, as well as specific osmotically regulated changes linked to cellular responses induced by dehydration. However, a small proportion (5.5% of total up-regulated genes represented a shared response that seemed to integrate the two signaling pathways. These co-regulated genes were considered downstream targets based on similar induction kinetics and a synergistic response to the combination of osmotic- and ER-stress-inducing treatments. Genes in this integrated pathway with the strongest synergistic induction encoded proteins with diverse roles, such as plant-specific development and cell death (DCD domain-containing proteins, an ubiquitin-associated (UBA protein homolog and NAC domain-containing proteins. This integrated pathway diverged further from characterized specific branches of ER-stress as

  9. The correlation between fragility, density, and atomic interaction in glass-forming liquids.

    Science.gov (United States)

    Wang, Lijin; Guan, Pengfei; Wang, W H

    2016-07-21

    The fragility that controls the temperature-dependent viscous properties of liquids as the glass transition is approached, in various glass-forming liquids with different softness of the repulsive part of atomic interactions at different densities, is investigated by molecular dynamic simulations. We show that the landscape of fragility in purely repulsive systems can be separated into three regions denoted as RI, RII, and RIII, respectively, with qualitatively disparate dynamic behaviors: RI which can be described by "softness makes strong glasses," RII where fragility is independent of softness and can only be tuned by density, and RIII with constant fragility, suggesting that density plays an unexpected role for understanding the repulsive softness dependence of fragility. What is more important is that we unify the long-standing inconsistence with respect to the repulsive softness dependence of fragility by observing that a glass former can be tuned more fragile if nonperturbative attraction is added into it. Moreover, we find that the vastly dissimilar influences of attractive interaction on fragility could be estimated from the structural properties of related zero-temperature glasses.

  10. Component Fragility Research Program: Phase 1 component prioritization

    International Nuclear Information System (INIS)

    Holman, G.S.; Chou, C.K.

    1987-06-01

    Current probabilistic risk assessment (PRA) methods for nuclear power plants utilize seismic ''fragilities'' - probabilities of failure conditioned on the severity of seismic input motion - that are based largely on limited test data and on engineering judgment. Under the NRC Component Fragility Research Program (CFRP), the Lawrence Livermore National Laboratory (LLNL) has developed and demonstrated procedures for using test data to derive probabilistic fragility descriptions for mechanical and electrical components. As part of its CFRP activities, LLNL systematically identified and categorized components influencing plant safety in order to identify ''candidate'' components for future NRC testing. Plant systems relevant to safety were first identified; within each system components were then ranked according to their importance to overall system function and their anticipated seismic capacity. Highest priority for future testing was assigned to those ''very important'' components having ''low'' seismic capacity. This report describes the LLNL prioritization effort, which also included application of ''high-level'' qualification data as an alternate means of developing probabilistic fragility descriptions for PRA applications

  11. Studies of Protein Solution Properties Using Osmotic Pressure Measurements

    Science.gov (United States)

    Agena, S.; Bogle, David; Pusey, Marc; Agena, S.

    1998-01-01

    Examination of the protein crystallization process involves investigation of the liquid and solid state and a protein's properties in these states. Liquid state studies such as protein self association in solution by light scattering methods or other methods have been used to examine a protein Is properties and therefore its crystallization process and conditions. Likewise can osmotic pressure data be used to examine protein properties and various published osmotic pressure studies were examined by us to correlate osmotic pressure to protein solution properties. The solution behavior of serum albumin, alpha - chymotrypsin, beta - lactoglobulin and ovalbumin was examined over a range of temperatures, pH values and different salt types and concentrations. Using virial expansion and a local composition model the non ideal solution behavior in form of the activity coefficients (thermodynamic) was described for the systems. This protein activity coefficient data was related to a protein's solubility behavior and this process and the results will be presented.

  12. Folding propensity of intrinsically disordered proteins by osmotic stress

    International Nuclear Information System (INIS)

    Mansouri, Amanda L.; Grese, Laura N.; Rowe, Erica L.

    2016-01-01

    Proteins imparted with intrinsic disorder conduct a range of essential cellular functions. To better understand the folding and hydration properties of intrinsically disordered proteins (IDPs), we used osmotic stress to induce conformational changes in nuclear co-activator binding domain (NCBD) and activator for thyroid hormone and retinoid receptor (ACTR). Osmotic stress was applied by the addition of small and polymeric osmolytes, where we discovered that water contributions to NCBD folding always exceeded those for ACTR. Both NCBD and ACTR were found to gain a-helical structure with increasing osmotic stress, consistent with their folding upon NCBD/ACTR complex formation. Using small-angle neutron scattering (SANS), we further characterized NCBD structural changes with the osmolyte ethylene glycol. Here a large reduction in overall size initially occurred before substantial secondary structural change. In conclusion, by focusing on folding propensity, and linked hydration changes, we uncover new insights that may be important for how IDP folding contributes to binding.

  13. Molecular characterization of X chromosome fragility in idiopathic ...

    African Journals Online (AJOL)

    Background: Fragile X syndrome (FXS) is the most common form of inherited mental retardation. Frequency of fragile X syndrome among male siblings and relatives of mentally retarded patients is relatively high. Cytogenetic diagnosis of FXS is unreliable since it is ineffective for the diagnosis of premutated males or ...

  14. Laboratory investigation of steam transmission in unsaturated clayey soil under osmotic potential

    Directory of Open Access Journals (Sweden)

    Mehdi Jalili

    2017-01-01

    Full Text Available Liquids coming from different sources like wastewaters, agricultural and industrial activities and leakages of chemical substances often have high concentration of chemical compositions and the osmotic gradient generated around such sources causes a considerable transmission of the Contamination. The steam transmitted by non-polluted soils moves to polluted masses, causing an increase in the volume of pollution zone and movement of pollutants. Therefore, such physical and chemical processes should be taken into account in pollution transmission models. Using Crumb method, laboratory investigations were conducted on non-dispersive and dispersive clayey soil samples obtained from three areas in Zanjan Province of Iran. A simple experimental setup has been used and hereby introduced. The impact of osmotic force from salinities of 0.5, 1, and 1.5% on steam transmission in clayey soil was examined. Results indicate that for all samples between 5 to 15 days, the moisture content increased in the pollutant zone and decreased in the non-pollutant area. Also it was observed that for dispersive clayey soil, movement of steam among layers was observed to be orderly and its amount was higher than that of non-dispersive clayey soil.

  15. Fragile-to-fragile liquid transition at Tg and stable-glass phase nucleation rate maximum at the Kauzmann temperature TK

    International Nuclear Information System (INIS)

    Tournier, Robert F.

    2014-01-01

    An undercooled liquid is unstable. The driving force of the glass transition at T g is a change of the undercooled-liquid Gibbs free energy. The classical Gibbs free energy change for a crystal formation is completed including an enthalpy saving. The crystal growth critical nucleus is used as a probe to observe the Laplace pressure change Δp accompanying the enthalpy change −V m ×Δp at T g where V m is the molar volume. A stable glass–liquid transition model predicts the specific heat jump of fragile liquids at T≤T g , the Kauzmann temperature T K where the liquid entropy excess with regard to crystal goes to zero, the equilibrium enthalpy between T K and T g , the maximum nucleation rate at T K of superclusters containing magic atom numbers, and the equilibrium latent heats at T g and T K . Strong-to-fragile and strong-to-strong liquid transitions at T g are also described and all their thermodynamic parameters are determined from their specific heat jumps. The existence of fragile liquids quenched in the amorphous state, which do not undergo liquid–liquid transition during heating preceding their crystallization, is predicted. Long ageing times leading to the formation at T K of a stable glass composed of superclusters containing up to 147 atom, touching and interpenetrating, are evaluated from nucleation rates. A fragile-to-fragile liquid transition occurs at T g without stable-glass formation while a strong glass is stable after transition

  16. Experimental Support for a Predictive Osmotic Model of Clay Membranes

    International Nuclear Information System (INIS)

    Fritz, S.J.

    2001-01-01

    Osmosis has been cited as a mechanism for explaining anomalously high fluid pressures in the subsurface. Clays and shales act as membranes, and osmotic flux across these units may result in pressures sufficiently high to explain these anomalies. The theoretical osmotic pressures as calculated solely from solution properties can be quite large; however, it is not yet resolved whether these geologic membranes are sufficiently ideal to generate such pressures

  17. Invertible chaotic fragile watermarking for robust image authentication

    International Nuclear Information System (INIS)

    Sidiropoulos, Panagiotis; Nikolaidis, Nikos; Pitas, Ioannis

    2009-01-01

    Fragile watermarking is a popular method for image authentication. In such schemes, a fragile signal that is sensitive to manipulations is embedded in the image, so that it becomes undetectable after any modification of the original work. Most algorithms focus either on the ability to retrieve the original work after watermark detection (invertibility) or on detecting which image parts have been altered (localization). Furthermore, the majority of fragile watermarking schemes suffer from robustness flaws. We propose a new technique that combines localization and invertibility. Moreover, watermark dependency on the original image and the non-linear watermark embedding procedure guarantees that no malicious attacks will manage to create information leaks.

  18. Clinical neurogenetics: fragile x-associated tremor/ataxia syndrome.

    Science.gov (United States)

    Hall, Deborah A; O'Keefe, Joan A

    2013-11-01

    This article summarizes the clinical findings, genetics, pathophysiology, and treatment of fragile X-associated tremor ataxia syndrome. The disorder occurs from a CGG repeat (55-200) expansion in the fragile X mental retardation 1 gene. It manifests clinically in kinetic tremor, gait ataxia, and executive dysfunction, usually in older men who carry the genetic abnormality. The disorder has distinct radiographic and pathologic findings. Symptomatic treatment is beneficial in some patients. The inheritance is X-linked and family members may be at risk for other fragile X-associated disorders. This information is useful to neurologists, general practitioners, and geneticists. Copyright © 2013. Published by Elsevier Inc.

  19. SAXS investigations on lipid membranes under osmotic stress

    Energy Technology Data Exchange (ETDEWEB)

    Rubim, R.L.; Vieira, V.; Gerbelli, B.B.; Teixeira da Silva, E.R.; Oliveira, C.L.P.; Oliveira, E.A. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil)

    2012-07-01

    Full text: In this work we, experimentally, investigate the interactions between lipid bilayers. A structural characterization is performed by small angle x-ray scattering (SAXS) on multilamellar systems under known osmotic pressure. Changes in the composition of membranes can modify their mechanical properties and structural parameters, like the flexibility of these membranes, which plays a key role on the determination of the tridimensional organization of bilayers. The membranes are composed of soya lecithin, where the major component is DPPC (Dipalmitoylphosphatidylcholine), and fatty acids are incorporated to the membrane in different concentrations, in order to turn the membrane more fluid. The membranes are inserted in a solution of PVP [poly(vinyl-pyrrolidone) - 40000] and the polymer will apply an osmotic pressure on them. The osmotic pressure is controlled by preparing PVP solutions of desired composition and, as we know the concentration of polymer in solution, we can obtain the intensity of the osmotic pressure. SAXS experiments were done in order to determine the distance between the bilayer. From the position of the Bragg peaks, the lamellar periodicity (the thickness of the membranes plus their distance of separation) was determined. Using theoretical model for the form and structure factors we fitted those experimental data and determined the thickness of the membranes. The distance between the membranes was controlled by the osmotic pressure (P) applied to the membranes and, for a given pressure, we determine the distance between the bilayers (a) on equilibrium. The experimental curve P(a) is theoretically described by the different contributions from van der Waals, hydration and fluctuation forces. From the fitting of experimental curves, relevant parameters characterizing the strength of the different interactions are obtained, such as Hamaker and rigidity constant [2, 3]. We observe that the separation between the bilayers on equilibrium is

  20. Genetics Home Reference: fragile X-associated primary ovarian insufficiency

    Science.gov (United States)

    ... Share: Email Facebook Twitter Home Health Conditions FXPOI Fragile X-associated primary ovarian insufficiency Printable PDF Open All ... Javascript to view the expand/collapse boxes. Description Fragile X-associated primary ovarian insufficiency ( FXPOI ) is a condition ...

  1. Genetics Home Reference: fragile X-associated tremor/ataxia syndrome

    Science.gov (United States)

    ... Share: Email Facebook Twitter Home Health Conditions FXTAS Fragile X-associated tremor/ataxia syndrome Printable PDF Open All ... Javascript to view the expand/collapse boxes. Description Fragile X-associated tremor/ataxia syndrome ( FXTAS ) is characterized by ...

  2. The correlation between fragility, density, and atomic interaction in glass-forming liquids

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lijin; Guan, Pengfei, E-mail: pguan@csrc.ac.cn [Beijing Computational Science Research Center, Beijing 100193 (China); Wang, W. H. [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2016-07-21

    The fragility that controls the temperature-dependent viscous properties of liquids as the glass transition is approached, in various glass-forming liquids with different softness of the repulsive part of atomic interactions at different densities, is investigated by molecular dynamic simulations. We show that the landscape of fragility in purely repulsive systems can be separated into three regions denoted as R{sub I,} R{sub II}, and R{sub III}, respectively, with qualitatively disparate dynamic behaviors: R{sub I} which can be described by “softness makes strong glasses,” R{sub II} where fragility is independent of softness and can only be tuned by density, and R{sub III} with constant fragility, suggesting that density plays an unexpected role for understanding the repulsive softness dependence of fragility. What is more important is that we unify the long-standing inconsistence with respect to the repulsive softness dependence of fragility by observing that a glass former can be tuned more fragile if nonperturbative attraction is added into it. Moreover, we find that the vastly dissimilar influences of attractive interaction on fragility could be estimated from the structural properties of related zero-temperature glasses.

  3. The correlation between fragility, density, and atomic interaction in glass-forming liquids

    International Nuclear Information System (INIS)

    Wang, Lijin; Guan, Pengfei; Wang, W. H.

    2016-01-01

    The fragility that controls the temperature-dependent viscous properties of liquids as the glass transition is approached, in various glass-forming liquids with different softness of the repulsive part of atomic interactions at different densities, is investigated by molecular dynamic simulations. We show that the landscape of fragility in purely repulsive systems can be separated into three regions denoted as R I, R II , and R III , respectively, with qualitatively disparate dynamic behaviors: R I which can be described by “softness makes strong glasses,” R II where fragility is independent of softness and can only be tuned by density, and R III with constant fragility, suggesting that density plays an unexpected role for understanding the repulsive softness dependence of fragility. What is more important is that we unify the long-standing inconsistence with respect to the repulsive softness dependence of fragility by observing that a glass former can be tuned more fragile if nonperturbative attraction is added into it. Moreover, we find that the vastly dissimilar influences of attractive interaction on fragility could be estimated from the structural properties of related zero-temperature glasses.

  4. Correlation Between Superheated Liquid Fragility And Onset Temperature Of Crystallization For Al-Based Amorphous Alloys

    Directory of Open Access Journals (Sweden)

    Guo J.

    2015-06-01

    Full Text Available Amorphous alloys or metallic glasses have attracted significant interest in the materials science and engineering communities due to their unique physical, mechanical, and chemical properties. The viscous flow of amorphous alloys exhibiting high strain rate sensitivity and homogeneous deformation is considered to be an important characteristic in thermoplastic forming processes performed within the supercooled liquid region because it allows superplastic-like deformation behavior. Here, the correlation between the superheated liquid fragility, and the onset temperature of crystallization for Al-based alloys, is investigated. The activation energy for viscous flow of the liquid is also investigated. There is a negative correlation between the parameter of superheated liquid fragility and the onset temperature of crystallization in the same Al-based alloy system. The activation energy decreases as the onset temperature of crystallization increases. This indicates that the stability of a superheated liquid can affect the thermal stability of the amorphous alloy. It also means that a liquid with a large superheated liquid fragility, when rapidly solidified, forms an amorphous alloy with a low thermal stability.

  5. Screening and diagnosis for the fragile X syndrome among the mentally retarded: an epidemiological and psychological survey. Collaborative Fragile X Study Group

    NARCIS (Netherlands)

    B.B.A. de Vries (Bert); B.A. Oostra (Ben); M.F. Niermeijer (Martinus); A. Tibben (Arend); A.M.W. van den Ouweland (Ans); S. Mohkamsing; H.J. Duivenvoorden (Hugo); E. Mol; K. Gelsema; M. van Rijn; D.J.J. Halley (Dicky); L.A. Sandkuijl (Lodewijk)

    1997-01-01

    textabstractThe fragile X syndrome is an X-linked mental retardation disorder caused by an expanded CGG repeat in the first exon of the fragile X mental retardation (FMR1) gene. Its frequency, X-linked inheritance, and consequences for relatives all prompt for

  6. A bHLH gene from Tamarix hispida improves abiotic stress tolerance by enhancing osmotic potential and decreasing reactive oxygen species accumulation.

    Science.gov (United States)

    Ji, Xiaoyu; Nie, Xianguang; Liu, Yujia; Zheng, Lei; Zhao, Huimin; Zhang, Bing; Huo, Lin; Wang, Yucheng

    2016-02-01

    Basic helix-loop-helix (bHLH) leucine-zipper transcription factors play important roles in abiotic stress responses. However, their specific roles in abiotic stress tolerance are not fully known. Here, we functionally characterized a bHLH gene, ThbHLH1, from Tamarix hispida in abiotic stress tolerance. ThbHLH1 specifically binds to G-box motif with the sequence of 'CACGTG'. Transiently transfected T. hispida plantlets with transiently overexpressed ThbHLH1 and RNAi-silenced ThbHLH1 were generated for gain- and loss-of-function analysis. Transgenic Arabidopsis thaliana lines overexpressing ThbHLH1 were generated to confirm the gain- and loss-of-function analysis. Overexpression of ThbHLH1 significantly elevates glycine betaine and proline levels, increases Ca(2+) concentration and enhances peroxidase (POD) and superoxide dismutase (SOD) activities to decrease reactive oxygen species (ROS) accumulation. Additionally, ThbHLH1 regulates the expression of the genes including P5CS, BADH, CaM, POD and SOD, to activate the above physiological changes, and also induces the expression of stress tolerance-related genes LEAs and HSPs. These data suggest that ThbHLH1 induces the expression of stress tolerance-related genes to improve abiotic stress tolerance by increasing osmotic potential, improving ROS scavenging capability and enhancing second messenger in stress signaling cascades. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Recommendation to use iso-osmotic contrast medium in interventional treatment

    International Nuclear Information System (INIS)

    Zhou Bing; Cheng Yongde

    2012-01-01

    With the rapid development of imaging diagnostic and interventional therapeutic techniques, the contrast medium (CM) has been used more and more common in clinical practice, and meanwhile more and more attention has been paid to the CM-related adverse events. Contrast induced nephropathy (CN) is the most common CM-related adverse event, and CM-related neurotoxicity has already attracted the physicians' attention. The osmotic pressure of the iso-osmotic contrast medium (IOCM) is quite the same as that of the plasma, and therefore its safety is higher than that of low-osmotic contrast medium (LOCM), the patient's tolerance to IOCM is better than that to LOCM. For this reason, the use of IOCM should be strongly recommended in interventional procedures, which is of great significance to the reduction of the occurrence of CM-related adverse events. (authors)

  8. The Arabidopsis Vacuolar Sorting Receptor1 Is Required for Osmotic Stress-Induced Abscisic Acid Biosynthesis

    KAUST Repository

    Wang, Zhen-Yu; Gehring, Christoph A; Zhu, Jianhua; Li, Feng-Min; Zhu, Jian-Kang; Xiong, Liming

    2014-01-01

    Osmotic stress activates the biosynthesis of the phytohormone abscisic acid (ABA) through a pathway that is rate limited by the carotenoid cleavage enzyme 9-cis-epoxycarotenoid dioxygenase (NCED). To understand the signal transduction mechanism underlying the activation of ABA biosynthesis, we performed a forward genetic screen to isolate mutants defective in osmotic stress regulation of the NCED3 gene. Here, we identified the Arabidopsis (Arabidopsis thaliana) Vacuolar Sorting Receptor1 (VSR1) as a unique regulator of ABA biosynthesis. The vsr1 mutant not only shows increased sensitivity to osmotic stress, but also is defective in the feedback regulation of ABA biosynthesis by ABA. Further analysis revealed that vacuolar trafficking mediated by VSR1 is required for osmotic stress-responsive ABA biosynthesis and osmotic stress tolerance. Moreover, under osmotic stress conditions, the membrane potential, calcium flux, and vacuolar pH changes in the vsr1 mutant differ from those in the wild type. Given that manipulation of the intracellular pH is sufficient to modulate the expression of ABA biosynthesis genes, including NCED3, and ABA accumulation, we propose that intracellular pH changes caused by osmotic stress may play a signaling role in regulating ABA biosynthesis and that this regulation is dependent on functional VSR1.

  9. The Arabidopsis Vacuolar Sorting Receptor1 Is Required for Osmotic Stress-Induced Abscisic Acid Biosynthesis

    KAUST Repository

    Wang, Zhen-Yu

    2014-11-21

    Osmotic stress activates the biosynthesis of the phytohormone abscisic acid (ABA) through a pathway that is rate limited by the carotenoid cleavage enzyme 9-cis-epoxycarotenoid dioxygenase (NCED). To understand the signal transduction mechanism underlying the activation of ABA biosynthesis, we performed a forward genetic screen to isolate mutants defective in osmotic stress regulation of the NCED3 gene. Here, we identified the Arabidopsis (Arabidopsis thaliana) Vacuolar Sorting Receptor1 (VSR1) as a unique regulator of ABA biosynthesis. The vsr1 mutant not only shows increased sensitivity to osmotic stress, but also is defective in the feedback regulation of ABA biosynthesis by ABA. Further analysis revealed that vacuolar trafficking mediated by VSR1 is required for osmotic stress-responsive ABA biosynthesis and osmotic stress tolerance. Moreover, under osmotic stress conditions, the membrane potential, calcium flux, and vacuolar pH changes in the vsr1 mutant differ from those in the wild type. Given that manipulation of the intracellular pH is sufficient to modulate the expression of ABA biosynthesis genes, including NCED3, and ABA accumulation, we propose that intracellular pH changes caused by osmotic stress may play a signaling role in regulating ABA biosynthesis and that this regulation is dependent on functional VSR1.

  10. Preserved entropy and fragile magnetism.

    Science.gov (United States)

    Canfield, Paul C; Bud'ko, Sergey L

    2016-08-01

    A large swath of quantum critical and strongly correlated electron systems can be associated with the phenomena of preserved entropy and fragile magnetism. In this overview we present our thoughts and plans for the discovery and development of lanthanide and transition metal based, strongly correlated systems that are revealed by suppressed, fragile magnetism, quantum criticality, or grow out of preserved entropy. We will present and discuss current examples such as YbBiPt, YbAgGe, YbFe2Zn20, PrAg2In, BaFe2As2, CaFe2As2, LaCrSb3 and LaCrGe3 as part of our motivation and to provide illustrative examples.

  11. Fragility and cooperativity concepts in hydrogen-bonded organic glasses

    International Nuclear Information System (INIS)

    Delpouve, N.; Vuillequez, A.; Saiter, A.; Youssef, B.; Saiter, J.M.

    2012-01-01

    Molecular dynamics at the glass transition of three lactose/oil glassy systems have been investigated according to the cooperativity and fragility approaches. From Donth's approach, the cooperativity length is estimated by modulated temperature calorimetric measurements. Results reveal that modification of the disaccharide by oil leads to increase the disorder degree in the lactose, the size of the cooperative domains and the fragility index. These particular hydrogen-bonded organic glasses follow the general tendency observed on organic and inorganic polymers: the higher the cooperativity length, the higher the value of the fragility index at T g .

  12. The safety of osmotically acting cathartics in colonic cleansing

    DEFF Research Database (Denmark)

    Nyberg, Caroline; Hendel, J.; Nielsen, O.H.

    2010-01-01

    Efficient cleansing of the colon before a colonoscopy or a radiological examination is essential. The osmotically acting cathartics (those given the Anatomical Therapeutic Chemical code A06AD) currently used for this purpose comprise products based on three main substances: sodium phosphate...... hyperphosphatemia and irreversible kidney damage owing to acute phosphate nephropathy, have been reported after use of sodium-phosphate-based products. The aim of this Review is to provide an update on the potential safety issues related to the use of osmotically acting cathartics, especially disturbances of renal...

  13. A cellulose synthase-like protein is required for osmotic stress tolerance in Arabidopsis

    KAUST Repository

    Zhu, Jianhua; Lee, Byeongha; Dellinger, Michael T.; Cui, Xinping; Zhang, Changqing; Wu, Shang; Nothnagel, Eugene A.; Zhu, Jian-Kang

    2010-01-01

    Osmotic stress imposed by soil salinity and drought stress significantly affects plant growth and development, but osmotic stress sensing and tolerance mechanisms are not well understood. Forward genetic screens using a root-bending assay have

  14. Finiteness Marking in Boys with Fragile X Syndrome

    Science.gov (United States)

    Sterling, Audra M.; Rice, Mabel L.; Warren, Steven F.

    2012-01-01

    Purpose: The current study investigated finiteness marking (e.g., he walk "s", he walk "ed") in boys with fragile X syndrome (FXS); the boys were grouped based on receptive vocabulary (i.e., borderline, impaired). Method: Twenty-one boys with the full mutation of fragile X, between the ages of 8 and 16 years participated. The…

  15. Understanding Fast and Robust Thermo-osmotic Flows through Carbon Nanotube Membranes: Thermodynamics Meets Hydrodynamics.

    Science.gov (United States)

    Fu, Li; Merabia, Samy; Joly, Laurent

    2018-04-19

    Following our recent theoretical prediction of the giant thermo-osmotic response of the water-graphene interface, we explore the practical implementation of waste heat harvesting with carbon-based membranes, focusing on model membranes of carbon nanotubes (CNT). To that aim, we combine molecular dynamics simulations and an analytical model considering the details of hydrodynamics in the membrane and at the tube entrances. The analytical model and the simulation results match quantitatively, highlighting the need to take into account both thermodynamics and hydrodynamics to predict thermo-osmotic flows through membranes. We show that, despite viscous entrance effects and a thermal short-circuit mechanism, CNT membranes can generate very fast thermo-osmotic flows, which can overcome the osmotic pressure of seawater. We then show that in small tubes confinement has a complex effect on the flow and can even reverse the flow direction. Beyond CNT membranes, our analytical model can guide the search for other membranes to generate fast and robust thermo-osmotic flows.

  16. Synaptic vesicle dynamic changes in a model of fragile X.

    Science.gov (United States)

    Broek, Jantine A C; Lin, Zhanmin; de Gruiter, H Martijn; van 't Spijker, Heleen; Haasdijk, Elize D; Cox, David; Ozcan, Sureyya; van Cappellen, Gert W A; Houtsmuller, Adriaan B; Willemsen, Rob; de Zeeuw, Chris I; Bahn, Sabine

    2016-01-01

    Fragile X syndrome (FXS) is a single-gene disorder that is the most common heritable cause of intellectual disability and the most frequent monogenic cause of autism spectrum disorders (ASD). FXS is caused by an expansion of trinucleotide repeats in the promoter region of the fragile X mental retardation gene (Fmr1). This leads to a lack of fragile X mental retardation protein (FMRP), which regulates translation of a wide range of messenger RNAs (mRNAs). The extent of expression level alterations of synaptic proteins affected by FMRP loss and their consequences on synaptic dynamics in FXS has not been fully investigated. Here, we used an Fmr1 knockout (KO) mouse model to investigate the molecular mechanisms underlying FXS by monitoring protein expression changes using shotgun label-free liquid-chromatography mass spectrometry (LC-MS(E)) in brain tissue and synaptosome fractions. FXS-associated candidate proteins were validated using selected reaction monitoring (SRM) in synaptosome fractions for targeted protein quantification. Furthermore, functional alterations in synaptic release and dynamics were evaluated using live-cell imaging, and interpretation of synaptic dynamics differences was investigated using electron microscopy. Key findings relate to altered levels of proteins involved in GABA-signalling, especially in the cerebellum. Further exploration using microscopy studies found reduced synaptic vesicle unloading of hippocampal neurons and increased vesicle unloading in cerebellar neurons, which suggests a general decrease of synaptic transmission. Our findings suggest that FMRP is a regulator of synaptic vesicle dynamics, which supports the role of FMRP in presynaptic functions. Taken together, these studies provide novel insights into the molecular changes associated with FXS.

  17. Dilemmas in counselling females with the fragile X syndrome

    NARCIS (Netherlands)

    B.B.A. de Vries (Bert); H.M. van den Boer-van den Berg; M.F. Niermeijer (Martinus); A. Tibben (Arend)

    1999-01-01

    textabstractThe dilemmas in counselling a mildly retarded female with the fragile X syndrome and her retarded partner are presented. The fragile X syndrome is an X linked mental retardation disorder that affects males and, often less severely, females. Affected females

  18. Seismic fragilities for nuclear power plant risk studies

    International Nuclear Information System (INIS)

    Kennedy, R.P.; Ravindra, M.K.

    1983-01-01

    Seismic fragilities of critical structures and equipment are developed as families of conditional failure frequency curves plotted against peak ground acceleration. The procedure is based on available data combined with judicious extrapolation of design information on plant structures and equipment. Representative values of fragility parameters for typical modern nuclear power plants are provided. Based on the fragility evaluation for about a dozen nuclear power plants, it is proposed that unnecessary conservatism existing in current seismic design practice could be removed by properly accounting for inelastic energy absorption capabilities of structures. The paper discusses the key contributors to seismic risk and the significance of possible correlation between component failures and potential design and construction errors

  19. Physiological Correlates of Social Avoidance Behavior in Children and Adolescents with Fragile X Syndrome

    Science.gov (United States)

    Hall, Scott S.; Lightbody, Amy A.; Huffman, Lynne C.; Lazzeroni, Laura C.; Reiss, Allan L.

    2009-01-01

    The heart rate and eye-gaze avoidance of 50 boys and girls with fragile X syndrome were monitored and it was found that those with this condition has significantly higher heart rates, lower vagal tones, and lower heart rate variability estimates when compared to their sibling. Eye-gaze avoidance decreased slightly over the course of the 25-minute…

  20. Effective updating process of seismic fragilities using Bayesian method and information entropy

    International Nuclear Information System (INIS)

    Kato, Masaaki; Takata, Takashi; Yamaguchi, Akira

    2008-01-01

    Seismic probabilistic safety assessment (SPSA) is an effective method for evaluating overall performance of seismic safety of a plant. Seismic fragilities are estimated to quantify the seismically induced accident sequences. It is a great concern that the SPSA results involve uncertainties, a part of which comes from the uncertainty in the seismic fragility of equipment and systems. A straightforward approach to reduce the uncertainty is to perform a seismic qualification test and to reflect the results on the seismic fragility estimate. In this paper, we propose a figure-of-merit to find the most cost-effective condition of the seismic qualification tests about the acceleration level and number of components tested. Then a mathematical method to reflect the test results on the fragility update is developed. A Bayesian method is used for the fragility update procedure. Since a lognormal distribution that is used for the fragility model does not have a Bayes conjugate function, a parameterization method is proposed so that the posterior distribution expresses the characteristics of the fragility. The information entropy is used as the figure-of-merit to express importance of obtained evidence. It is found that the information entropy is strongly associated with the uncertainty of the fragility. (author)

  1. Effect of osmotic stress on in vitro propagation of Musa sp. (Malbhog ...

    African Journals Online (AJOL)

    This study demonstrates up to 36% reduced microbial contamination in aseptic culture establishment and subsequent micropropagation due to osmotic stress induction in the banana suckers. Osmotic stress was induced by keeping the freshly collected suckers in shade and measuring fresh weight at 0, 7, 14, 21, and 28 ...

  2. Forests, Fragility and Conflict : Overview and Case Studies

    OpenAIRE

    Harwell, Emily; Farah, Douglas; Blundell, Arthur G.

    2011-01-01

    This book provides a synthesis of key themes and current knowledge about the links among forests, armed conflict, poverty, and various aspects of state fragility. The main themes addressed are: how predatory, incapable, or absent states are fragile in different ways, and their diverse relationships to forests and conflict; the mechanisms by which forests facilitate or prolong conflict, inc...

  3. Data-Driven Decision Making in Fragile Contexts : Evidence from Sudan

    OpenAIRE

    Hamilton, Alexander; Hammer, Craig

    2017-01-01

    Data deficiencies contribute to state fragility and exacerbate fragile states’ already limited capacity to provide basic services, public security and rule of law. The lack of robust, good quality data can also have a disabling effect on government efforts to manage political conflict, and indeed can worsen conflict, since violent settings pose substantial challenges to knowledge generation, capture and application. In short, in fragile contexts the need for reliable evidence at all levels ...

  4. Bayesian methodology for generic seismic fragility evaluation of components in nuclear power plants

    International Nuclear Information System (INIS)

    Yamaguchi, Akira; Campbell, R.D.; Ravindra, M.K.

    1991-01-01

    Bayesian methodology for updating the seismic fragility of components in nuclear power plants is presented. The generic fragility data which have been evaluated based on the past SPSAs are combined with the seismic experience data. Although the seismic experience is limited to the acceleration range below the median capacity of the components, it has been found that the evidence is effective to update the fragility tail. In other words, the uncertainty of the fragility is reduced although the median capacity itself is not modified to a great extent. The annual frequency of failure is also reduced as a result of the updating of the fragility tail. The PDF of the seismic capacity is handled in discrete form, which enables the use of arbitrary type of prior distribution. Accordingly, the Log-N prior can be used which is consistent with the widely used fragility model. For evaluating posterior fragility parameters (A m and B U ), two methods have been proposed. Furthermore, it has been found that the importance of evidence used in the Bayesian methodology can be quantified by the entropy of the evidence. Only the events with high entropy need to be considered in the Bayesian updating of the fragility. The currently available seismic experience database for typical components can be utilized to develop the fragility tail which is contributive to the seismically-induced failure frequency. The combined use of generic fragility and seismic experience data, with the aid of Bayesian methodology, provides refined generic fragility curves which are useful for SPSA studies. (author)

  5. Study on enhanced lymphatic tracing of isosulfan blue injection by influence of osmotic pressure on lymphatic exposure.

    Science.gov (United States)

    Ye, Tiantian; He, Rui; Wu, Yue; Shang, Lei; Wang, Shujun

    2018-04-01

    Isosulfan blue (IB) is being used as a lymphatic tracer has been approved by the FDA in 1981. This study aimed at improving lymphatic exposure of IB injection by osmotic pressure regulation to achieve step-by step lymphatic tracing. First, IB injection with appropriate osmotic pressure, stability, and suitable pH was prepared. Next, the lymphatic tracing ability of different osmotic pressure was studied to determine the blue-stained state of IB in three-level lymph nodes after subcutaneous administration. Furthermore, pharmacokinetics of lymphatic drainage, lymph node uptake, and plasma concentration was investigate to explore the improving law of the lymphatic tracing by osmotic pressure, and combined with tissue irritation to determine the optimal osmotic pressure. At last, the tissue distribution in mice of IB injection which had the property of optimal osmotic pressure was investigated. The results showed that increasing osmotic pressure could significantly reduce injection site retention and increase IB concentration of lymph node. The lymph nodes could be obviously blue-stained by IB injection which had 938 mmol/kg osmotic pressure and would not cause inflammatory reaction and blood exposure. The tissue distribution study suggested that IB injection which had 938 mmol/kg osmotic pressure was mainly distributed into gallbladder and duodenum that verified the reports that 90% IB was excreted through the feces through biliary excretion. In conclusion, this study provides the basic study to improve lymphatic exposure of IB injection by regulate the osmotic pressure and have the potential to be the helpful guidance for the elective lymph node dissection.

  6. Osmotic and stimulant laxatives for the management of childhood constipation

    OpenAIRE

    Gordon, Morris; Macdonald, John; Parker, Claire; Akobeng, Anthony; Thomas, Adrian

    2016-01-01

    Background\\ud \\ud Constipation within childhood is an extremely common problem. Despite the widespread use of osmotic and stimulant laxatives by health professionals to manage constipation in children, there has been a long standing paucity of high quality evidence to support this practice.\\ud \\ud \\ud Objectives\\ud \\ud We set out to evaluate the efficacy and safety of osmotic and stimulant laxatives used to treat functional childhood constipation.\\ud \\ud \\ud Search methods\\ud \\ud We searched ...

  7. Optimization of osmotic dehydration of chestnut (Castanea sativa Mill. slices using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Teresa Delgado

    2018-04-01

    Full Text Available Osmotic dehydration of chestnut slices in sucrose was optimized for the first time by Response Surface Methodology (RSM. Experiments were planned according to a three-factor central composite design (α=1.68, studying the influence of sucrose concentration, temperature and time, on the following parameters: volume ratio, water activity, color variation, weight reduction, solids gain, water loss and normalized moisture content, as well as total moisture, ash and fat contents. The experimental data was adequately fitted into second-order polynomial models with coefficients of determination (R2 from 0.716 to 0.976, adjusted-R2 values from 0.460 to 0.954, and non-significant lacks of fit. The optimal osmotic dehydration process conditions for maximum water loss and minimum solids gain and color variation were determined by the “Response Optimizer” option: 83% sucrose concentration, 20 °C and 9.2 hours. Thus, the best operational conditions corresponded to high sugar concentration and low temperature, improving energy saving and decreasing the process costs.

  8. The highly fragile glass former Decalin

    International Nuclear Information System (INIS)

    Eibl, Stefan

    2009-01-01

    Systems exhibiting the glass transition can be classified by fragility. In this work we studied structural and dynamical aspects of highly fragile C 10 H 18 Decalin. Trans Decalin is locked into a pseudo-flat centrosymmetric conformation, while cis Decalin interchanges dynamically between chiral, pseudo-spherical ground states. On investigation of the phase behaviour trans Decalin was found to crystallise rapidly and cleanly; its crystal structure could be determined. From the crystal structure the dynamics of crystalline trans Decalin could be calculated using ab-initio lattice energy calculations and compared to measurements. Using neutron diffraction and molecular dynamics simulations the amorphous structure of Decalin was investigated. The difference in structure to the common molecular liquid Cumene is significant. The features of the amorphous structure of sphere-like cis Decalin show strong resemblance to the ones of Argon and metallic glasses. The dynamics of Decalin were investigated in the slightly supercooled liquid range. Using neutron scattering and optical spectroscopy, data was collected for a wide spectral range and several temperatures. The data suggests high fragility for the generic Decalin mixture, which is in agreement with the reported results. By contrast to previous estimations, an extrapolation of our data indicates cis Decalin to be only slightly less fragile than the generic mixture. Finally a lower limit to the four point susceptibility function χ 4 could be calculated and the number of correlated molecules determined. The evolution of this value as a function of T g /T and relaxation time are in agreement with literature. (author) [fr

  9. Solute Transfer in Osmotic Dehydration of Vegetable Foods: A Review.

    Science.gov (United States)

    Muñiz-Becerá, Sahylin; Méndez-Lagunas, Lilia L; Rodríguez-Ramírez, Juan

    2017-10-01

    While various mechanisms have been proposed for the water transfer during osmotic dehydration (OD), little progress has been made to understand the mechanisms of solute transfer during osmotic dehydration. The transfer of solutes has been often described only by the diffusion mechanism; however, numerous evidences suggest the participation of a variety of mechanisms. This review deals with the main issues of solute transfer in the OD of vegetables. In this context, several studies suggest that during OD of fruits and vegetables, the migration of solutes is not influenced by diffusion. Thus, new theories that may explain the solute transport are analyzed, considering the influence of the plant microstructure and its interaction with the physicochemical properties of osmotic liquid media. In particular, the surface adhesion phenomenon is analyzed and discussed, as a possible mechanism present during the transfer of solutes in OD. © 2017 Institute of Food Technologists®.

  10. Osmotic stress response in the wine yeast Dekkera bruxellensis.

    Science.gov (United States)

    Galafassi, Silvia; Toscano, Marco; Vigentini, Ileana; Piškur, Jure; Compagno, Concetta

    2013-12-01

    Dekkera bruxellensis is mainly associated with lambic beer fermentation and wine production and may contribute in a positive or negative manner to the flavor development. This yeast is able to produce phenolic compounds, such as 4-ethylguaiacol and 4-ethylphenol which could spoil the wine, depending on their concentration. In this work we have investigated how this yeast responds when exposed to conditions causing osmotic stress, as high sorbitol or salt concentrations. We observed that osmotic stress determined the production and accumulation of intracellular glycerol, and the expression of NADH-dependent glycerol-3-phosphate dehydrogenase (GPD) activity was elevated. The involvement of the HOG MAPK pathway in response to this stress condition was also investigated. We show that in D. bruxellensis Hog1 protein is activated by phosphorylation under hyperosmotic conditions, highlighting the conserved role of HOG MAP kinase signaling pathway in the osmotic stress response. Gene Accession numbers in GenBank: DbHOG1: JX65361, DbSTL1: JX965362. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. A Trial of Metformin in Individuals With Fragile X Syndrome

    Science.gov (United States)

    2018-04-10

    Fragile X Syndrome; Fragile X Mental Retardation Syndrome; Mental Retardation, X Linked; Genetic Diseases, X-Linked; Trinucleotide Repeat Expansion; Fra(X) Syndrome; Intellectual Disability; FXS; Neurobehavioral Manifestations; Sex Chromosome Disorders

  12. Effects of Red Wine Tannat on Oxidative Stress Induced by Glucose and Fructose in Erythrocytes in Vitro

    Science.gov (United States)

    Pazzini, Camila Eliza Fernandes; Colpo, Ana Ceolin; Poetini, Márcia Rósula; Pires, Cauê Ferreira; de Camargo, Vanessa Brum; Mendez, Andreas Sebastian Loureiro; Azevedo, Miriane Lucas; Soares, Júlio César Mendes; Folmer, Vanderlei

    2015-01-01

    The literature indicates that red wine presents in its composition several substances that are beneficial to health. This study has investigated the antioxidant effects of Tannat red wine on oxidative stress induced by glucose and fructose in erythrocytes in vitro, with the purpose to determine some of its majoritarian phenolic compounds and its antioxidant capacity. Erythrocytes were incubated using different concentrations of glucose and fructose in the presence or absence of wine. From these erythrocytes were determined the production of thiobarbituric acid reactive species (TBARS), glucose consumption, and osmotic fragility. Moreover, quantification of total phenolic, gallic acid, caffeic acid, epicatechin, resveratrol, and DPPH scavenging activity in wine were also assessed. Red wine showed high levels of polyphenols analyzed, as well as high antioxidant potential. Erythrocytes incubated with glucose and fructose had an increase in lipid peroxidation and this was prevented by the addition of wine. The wine increased glucose uptake into erythrocytes and was able to decrease the osmotic fragility of erythrocytes incubated with fructose. Altogether, these results suggest that wine leads to a reduction of the oxidative stress induced by high concentrations of glucose and fructose. PMID:26078708

  13. Fragility and cooperativity concepts in hydrogen-bonded organic glasses

    Energy Technology Data Exchange (ETDEWEB)

    Delpouve, N., E-mail: delpouve.nicolas@gmail.com [AMME-LECAP EA 4528 International Laboratory, University of Rouen, Avenue de l' Universite BP 12, 76801 Saint Etienne du Rouvray (France); Vuillequez, A.; Saiter, A.; Youssef, B.; Saiter, J.M. [AMME-LECAP EA 4528 International Laboratory, University of Rouen, Avenue de l' Universite BP 12, 76801 Saint Etienne du Rouvray (France)

    2012-09-01

    Molecular dynamics at the glass transition of three lactose/oil glassy systems have been investigated according to the cooperativity and fragility approaches. From Donth's approach, the cooperativity length is estimated by modulated temperature calorimetric measurements. Results reveal that modification of the disaccharide by oil leads to increase the disorder degree in the lactose, the size of the cooperative domains and the fragility index. These particular hydrogen-bonded organic glasses follow the general tendency observed on organic and inorganic polymers: the higher the cooperativity length, the higher the value of the fragility index at T{sub g}.

  14. Seismic fragility analysis of structural components for HFBR facilities

    International Nuclear Information System (INIS)

    Park, Y.J.; Hofmayer, C.H.

    1992-01-01

    The paper presents a summary of recently completed seismic fragility analyses of the HFBR facilities. Based on a detailed review of past PRA studies, various refinements were made regarding the strength and ductility evaluation of structural components. Available laboratory test data were analysed to evaluate the formulations used to predict the ultimate strength and deformation capacities of steel, reinforced concrete and masonry structures. The biasness and uncertainties were evaluated within the framework of the fragility evaluation methods widely accepted in the nuclear industry. A few examples of fragility calculations are also included to illustrate the use of the presented formulations

  15. Osmotically driven membrane process for the management of urban runoff in coastal regions

    KAUST Repository

    Li, Zhenyu; Valladares Linares, Rodrigo; Abu-Ghdaib, Muhannad; Zhan, Tong; Yangali-Quintanilla, Victor; Amy, Gary L.

    2014-01-01

    An osmotic detention pond was proposed for the management of urban runoff in coastal regions. Forward osmosis was employed as a bridge to utilize natural osmotic energy from seawater for concentrating and reusing urban runoff water, and as a barrier

  16. Effect of calcium/sodium ion exchange on the osmotic properties and structure of polyelectrolyte gels.

    Science.gov (United States)

    Horkay, Ferenc; Basser, Peter J; Hecht, Anne-Marie; Geissler, Erik

    2015-12-01

    We discuss the main findings of a long-term research program exploring the consequences of sodium/calcium ion exchange on the macroscopic osmotic and elastic properties, and the microscopic structure of representative synthetic polyelectrolyte (sodium polyacrylate, (polyacrylic acid)) and biopolymer gels (DNA). A common feature of these gels is that above a threshold calcium ion concentration, they exhibit a reversible volume phase transition. At the macroscopic level, the concentration dependence of the osmotic pressure shows that calcium ions influence primarily the third-order interaction term in the Flory-Huggins model of polymer solutions. Mechanical tests reveal that the elastic modulus is practically unaffected by the presence of calcium ions, indicating that ion bridging does not create permanent cross-links. At the microscopic level, small-angle neutron scattering shows that polyacrylic acid and DNA gels exhibit qualitatively similar structural features in spite of important differences (e.g. chain flexibility and chemical composition) between the two polymers. The main effect of calcium ions is that the neutron scattering intensity increases due to the decrease in the osmotic modulus. At the level of the counterion cloud around dissolved macroions, anomalous small-angle X-ray scattering measurements made on DNA indicate that divalent ions form a cylindrical sheath enveloping the chain, but they are not localized. Small-angle neutron scattering and small-angle X-ray scattering provide complementary information on the structure and interactions in polymer solutions and gels. © IMechE 2015.

  17. Cell Wall Remodeling Enzymes Modulate Fungal Cell Wall Elasticity and Osmotic Stress Resistance.

    Science.gov (United States)

    Ene, Iuliana V; Walker, Louise A; Schiavone, Marion; Lee, Keunsook K; Martin-Yken, Hélène; Dague, Etienne; Gow, Neil A R; Munro, Carol A; Brown, Alistair J P

    2015-07-28

    The fungal cell wall confers cell morphology and protection against environmental insults. For fungal pathogens, the cell wall is a key immunological modulator and an ideal therapeutic target. Yeast cell walls possess an inner matrix of interlinked β-glucan and chitin that is thought to provide tensile strength and rigidity. Yeast cells remodel their walls over time in response to environmental change, a process controlled by evolutionarily conserved stress (Hog1) and cell integrity (Mkc1, Cek1) signaling pathways. These mitogen-activated protein kinase (MAPK) pathways modulate cell wall gene expression, leading to the construction of a new, modified cell wall. We show that the cell wall is not rigid but elastic, displaying rapid structural realignments that impact survival following osmotic shock. Lactate-grown Candida albicans cells are more resistant to hyperosmotic shock than glucose-grown cells. We show that this elevated resistance is not dependent on Hog1 or Mkc1 signaling and that most cell death occurs within 10 min of osmotic shock. Sudden decreases in cell volume drive rapid increases in cell wall thickness. The elevated stress resistance of lactate-grown cells correlates with reduced cell wall elasticity, reflected in slower changes in cell volume following hyperosmotic shock. The cell wall elasticity of lactate-grown cells is increased by a triple mutation that inactivates the Crh family of cell wall cross-linking enzymes, leading to increased sensitivity to hyperosmotic shock. Overexpressing Crh family members in glucose-grown cells reduces cell wall elasticity, providing partial protection against hyperosmotic shock. These changes correlate with structural realignment of the cell wall and with the ability of cells to withstand osmotic shock. The C. albicans cell wall is the first line of defense against external insults, the site of immune recognition by the host, and an attractive target for antifungal therapy. Its tensile strength is conferred by

  18. Agricultural Fragility Estimates Subjected to Volcanic Ash Fall Hazards

    Science.gov (United States)

    Ham, H. J.; Lee, S.; Choi, S. H.; Yun, W. S.

    2015-12-01

    Agricultural Fragility Estimates Subjected to Volcanic Ash Fall Hazards Hee Jung Ham1, Seung-Hun Choi1, Woo-Seok Yun1, Sungsu Lee2 1Department of Architectural Engineering, Kangwon National University, Korea 2Division of Civil Engineering, Chungbuk National University, Korea ABSTRACT In this study, fragility functions are developed to estimate expected volcanic ash damages of the agricultural sector in Korea. The fragility functions are derived from two approaches: 1) empirical approach based on field observations of impacts to agriculture from the 2006 eruption of Merapi volcano in Indonesia and 2) the FOSM (first-order second-moment) analytical approach based on distribution and thickness of volcanic ash observed from the 1980 eruption of Mt. Saint Helens and agricultural facility specifications in Korea. Fragility function to each agricultural commodity class is presented by a cumulative distribution function of the generalized extreme value distribution. Different functions are developed to estimate production losses from outdoor and greenhouse farming. Seasonal climate influences vulnerability of each agricultural crop and is found to be a crucial component in determining fragility of agricultural commodities to an ash fall. In the study, the seasonality coefficient is established as a multiplier of fragility function to consider the seasonal vulnerability. Yields of the different agricultural commodities are obtained from Korean Statistical Information Service to create a baseline for future agricultural volcanic loss estimation. Numerically simulated examples of scenario ash fall events at Mt. Baekdu volcano are utilized to illustrate the application of the developed fragility functions. Acknowledgements This research was supported by a grant 'Development of Advanced Volcanic Disaster Response System considering Potential Volcanic Risk around Korea' [MPSS-NH-2015-81] from the Natural Hazard Mitigation Research Group, Ministry of Public Safety and Security of

  19. The Seismic Fragility Evaluation of an Offsite Transformer according to Aging Effects

    International Nuclear Information System (INIS)

    Kim, Min Kyu; Choi, In Kil

    2008-01-01

    A seismic fragility analysis was performed, especially for an aged electric power transmission system, in this study. A real electric transformer system for Korean Nuclear Power Plants was selected for the seismic fragility evaluation. In the case of a seismic fragility analysis we should use design material properties and conditions. However material properties and environmental conditions of most structures and equipment are changed according to a lapse of time. Aging conditions greatly affect the integrity of the structures and equipment at NPP sites, but it is very difficult to estimate them qualitatively. Integrity of an anchor bolt system was considered with the aging conditions for an electric transformer system. At first, a seismic fragility analysis was performed for a fine condition for an electric transformer system. After that, a seismic fragility analysis according to the fastener of an anchor bolt system was conducted. This study showed that a looser anchor bolt creates seismic responses and seismic fragility changes of more 10%

  20. Suppressive effect of cellulose on osmotic diarrhea caused by maltitol in healthy female subjects.

    Science.gov (United States)

    Oku, Tsuneyuki; Hongo, Ryoko; Nakamura, Sadako

    2008-08-01

    Using a single-group time-series design, we determined that osmotic diarrhea caused by maltitol ingestion was suppressed by the addition of not only soluble but also insoluble dietary fiber in healthy humans. We then clarified that cellulose delayed gastric emptying in rats. Twenty-seven healthy volunteers ingested maltitol step-wise at doses of 15, 20, 25, 30, 35, 40 and 45 g from small to large amounts. Within that range of ingested amounts, 22 out of 27 subjects experienced osmotic diarrhea from maltitol ingestion, and the minimal dose level of maltitol that induced osmotic diarrhea (MMD) was established for each subject. When 5 g of cellulose was added to the MMD, osmotic diarrhea was suppressed in 13 out of 19 subjects (68.4%), while partially hydrolyzed alginate-Na (PHA-Na), a soluble dietary fiber, suppressed osmotic diarrhea in 10 out of 20 subjects (50.0%). When a mixed solution of cellulose and maltitol was administered to rats, the gastric emptying of maltitol was significantly delayed at 30 and 60 min after administration (p=0.019, p=0.013), respectively. PHA-Na also significantly delayed gastric emptying at 30 min (p=0.013). In conclusion, cellulose can suppress the osmotic diarrhea caused by maltitol ingestion in humans and delay the gastric emptying of maltitol in rats. A new physiological property of cellulose was clarified in this study.

  1. Lower critical solution temperature (LCST) phase separation of glycol ethers for forward osmotic control.

    Science.gov (United States)

    Nakayama, Daichi; Mok, Yeongbong; Noh, Minwoo; Park, Jeongseon; Kang, Sunyoung; Lee, Yan

    2014-03-21

    Lower critical solution temperature (LCST) phase transition of glycol ether (GE)-water mixtures induces an abrupt change in osmotic pressure driven by a mild temperature change. The temperature-controlled osmotic change was applied for the forward osmosis (FO) desalination. Among three GEs evaluated, di(ethylene glycol) n-hexyl ether (DEH) was selected as a potential FO draw solute. A DEH-water mixture with a high osmotic pressure could draw fresh water from a high-salt feed solution such as seawater through a semipermeable membrane at around 10 °C. The water-drawn DEH-water mixture was phase-separated into a water-rich phase and a DEH-rich phase at around 30 °C. The water-rich phase with a much reduced osmotic pressure released water into a low-salt solution, and the DEH-rich phase was recovered into the initial DEH-water mixture. The phase separation behaviour, the residual GE concentration in the water-rich phase, the osmotic pressure of the DEH-water mixture, and the osmotic flux between the DEH-water mixture and salt solutions were carefully analysed for FO desalination. The liquid-liquid phase separation of the GE-water mixture driven by the mild temperature change between 10 °C and 30 °C is very attractive for the development of an ideal draw solute for future practical FO desalination.

  2. Shelf-life extension of gilthead seabream fillets by osmotic treatment and antimicrobial agents.

    Science.gov (United States)

    Tsironi, T N; Taoukis, P S

    2012-02-01

    The objectives of the study were to evaluate the effect of selected antimicrobial agents on the shelf life of osmotically pretreated gilthead seabream and to establish reliable kinetic equations for shelf-life determination validated in dynamic conditions. Fresh gilthead seabream (Sparus aurata) fillets were osmotically treated with 50% high dextrose equivalent maltodextrin (HDM, DE 47) plus 5% NaCl and 0·5% carvacrol, 0·5% glucono-δ-lactone or 1% Citrox (commercial antimicrobial mix). Untreated and treated slices were aerobically packed and stored isothermally (0-15°C). Microbial growth and quality-related chemical indices were modelled as functions of temperature. Models were validated at dynamic storage conditions. Osmotic pretreatment with the use of antimicrobials led to significant shelf-life extension of fillets, in terms of microbial growth and organoleptic deterioration. The shelf life was 7 days for control samples at 5°C. The osmotic pretreatment with carvacrol, glucono-δ-lactone and Citrox allowed for shelf-life extension by 8, 10 and 5 days at 5°C, respectively. The results of the study show the potential of adding carvacrol, glucono-δ-lactone or Citrox in the osmotic solution to extend the shelf life and improve commercial value of chilled osmotically pretreated fish products. The developed models can be a reliable tool for predicting the shelf life of fresh or minimally processed gilthead seabream fillets in the real chill chain. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

  3. Screening for Osmotic Stress Responses in Rice Varieties under Drought Condition

    OpenAIRE

    Simon Swapna; Korukkanvilakath Samban Shylaraj

    2017-01-01

    Drought is the major abiotic stress factor that limits rice production worldwide. To evaluate the osmotic stress responses in rice varieties under drought condition, a total of 42 high-yielding rice varieties were collected from various research stations of Kerala Agricultural University in India. The experimental setup comprises of initial hydroponic treatments at different osmotic potentials, artificially induced by desired strengths of polyethylene glycol (PEG6000), and followed by the pot...

  4. Chloroplast osmotic adjustment allows for acclimation of photosynthesis to low water potentials

    International Nuclear Information System (INIS)

    Gupta, A.S.; Berkowitz, G.

    1987-01-01

    Previously in this laboratory, studies indicated that photosynthesis (PS) of chloroplasts isolated from spinach plants which underwent osmotic adjustment during in situ water deficits was inhibited less at low osmotic potentials (Psi/sub s/) in vitro than PS of plastids isolated from well watered plants. In this study, an attempt was made to determine if chloroplast acclimation to low Psi/sub s/ was associated with in situ stromal solute accumulation. During a 14d stress cycle, in situ stromal volume was estimated by measuring (using the 3 H 2 O, 14 C-sorbitol silicon oil centrifugation technique) the stromal space of plastids in solutions which had the Psi/sub s/ adjusted to the leaf Psi/sub s/. During the first lid of the cycle, stromal volume did not decline, despite a decrease of over 20% in the leaf RWC. After this time, stromal volume dropped rapidly. In situ stromal Psi/sub s/ was also estimated during a stress cycle. These studies indicated that stromal Psi/sub s/ was lowered by net solute accumulation. The data presented in this report suggest that chloroplast acclimation to low Psi/sub s/ may involve stromal solute accumulation and volume maintenance during cell water loss

  5. Extracellular-matrix-mediated osmotic pressure drives Vibrio cholerae biofilm expansion and cheater exclusion.

    Science.gov (United States)

    Yan, Jing; Nadell, Carey D; Stone, Howard A; Wingreen, Ned S; Bassler, Bonnie L

    2017-08-23

    Biofilms, surface-attached communities of bacteria encased in an extracellular matrix, are a major mode of bacterial life. How the material properties of the matrix contribute to biofilm growth and robustness is largely unexplored, in particular in response to environmental perturbations such as changes in osmotic pressure. Here, using Vibrio cholerae as our model organism, we show that during active cell growth, matrix production enables biofilm-dwelling bacterial cells to establish an osmotic pressure difference between the biofilm and the external environment. This pressure difference promotes biofilm expansion on nutritious surfaces by physically swelling the colony, which enhances nutrient uptake, and enables matrix-producing cells to outcompete non-matrix-producing cheaters via physical exclusion. Osmotic pressure together with crosslinking of the matrix also controls the growth of submerged biofilms and their susceptibility to invasion by planktonic cells. As the basic physicochemical principles of matrix crosslinking and osmotic swelling are universal, our findings may have implications for other biofilm-forming bacterial species.Most bacteria live in biofilms, surface-attached communities encased in an extracellular matrix. Here, Yan et al. show that matrix production in Vibrio cholerae increases the osmotic pressure within the biofilm, promoting biofilm expansion and physical exclusion of non-matrix producing cheaters.

  6. Relation between lowered colloid osmotic pressure, respiratory failure, and death.

    Science.gov (United States)

    Tonnesen, A S; Gabel, J C; McLeavey, C A

    1977-01-01

    Plasma colloid osmotic pressure was measured each day in 84 intensive care unit patients. Probit analysis demonstrated a direct relationship between colloid osmotic pressure (COP) and survival. The COP associated with a 50% survival rate was 15.0 torr. COP was higher in survivors than in nonsurvivors without respiratory failure and in patients who recovered from respiratory failure. We conclude that lowered COP is associated with an elevated mortality rate. However, the relationship to death is not explained by the relationship to respiratory failure.

  7. Diagnostic, carrier and prenatal genetic testing for fragile X ...

    African Journals Online (AJOL)

    Background. Fragile X syndrome (FXS), the most common inherited cause of intellectual disability (ID) worldwide, is caused by the expansion of a CGG repeat in the fragile X mental retardation gene (FMR-1) gene. Objectives. To review, retrospectively, the genetic services for FXS and other FMR-1-related disorders ...

  8. Whole-of-Government Approaches to Fragile States in Africa

    DEFF Research Database (Denmark)

    Olsen, Gorm Rye

    2013-01-01

    For a number of years fragile states have been high on the foreign policy agendas of the USA and the EU. Both actors look upon fragile states with great concern and consider them as security threats. Officially they give priority to ‘whole-of-government approaches’ (wga) when addressing the threats...

  9. Cities could hold the key to understanding fragility | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Cities are engines of economic growth and the primary sites of basic service delivery. Yet weak governance, along with inequalities related to income, social class, religion, and gender, may lead to a breakdown of systems and structures, and eventually to "fragile cities." Although the fragile cities concept is relatively new, ...

  10. EMQN best practice guidelines for the molecular genetic testing and reporting of fragile X syndrome and other fragile X-associated disorders

    Science.gov (United States)

    Biancalana, Valérie; Glaeser, Dieter; McQuaid, Shirley; Steinbach, Peter

    2015-01-01

    Different mutations occurring in the unstable CGG repeat in 5' untranslated region of FMR1 gene are responsible for three fragile X-associated disorders. An expansion of over ∼200 CGG repeats when associated with abnormal methylation and inactivation of the promoter is the mutation termed ‘full mutation' and is responsible for fragile X syndrome (FXS), a neurodevelopmental disorder described as the most common cause of inherited intellectual impairment. The term ‘abnormal methylation' is used here to distinguish the DNA methylation induced by the expanded repeat from the ‘normal methylation' occurring on the inactive X chromosomes in females with normal, premutation, and full mutation alleles. All male and roughly half of the female full mutation carriers have FXS. Another anomaly termed ‘premutation' is characterized by the presence of 55 to ∼200 CGGs without abnormal methylation, and is the cause of two other diseases with incomplete penetrance. One is fragile X-associated primary ovarian insufficiency (FXPOI), which is characterized by a large spectrum of ovarian dysfunction phenotypes and possible early menopause as the end stage. The other is fragile X-associated tremor/ataxia syndrome (FXTAS), which is a late onset neurodegenerative disorder affecting males and females. Because of the particular pattern and transmission of the CGG repeat, appropriate molecular testing and reporting is very important for the optimal genetic counselling in the three fragile X-associated disorders. Here, we describe best practice guidelines for genetic analysis and reporting in FXS, FXPOI, and FXTAS, including carrier and prenatal testing. PMID:25227148

  11. Osmotic stress adaptation of Paracoccidioides lutzii, Pb01, monitored by proteomics.

    Science.gov (United States)

    Rodrigues, Leandro Nascimento da Silva; Brito, Wesley de Almeida; Parente, Ana Flávia Alves; Weber, Simone Schneider; Bailão, Alexandre Melo; Casaletti, Luciana; Borges, Clayton Luiz; Soares, Célia Maria de Almeida

    2016-10-01

    The ability to respond to stressful conditions is essential for most living organisms. In pathogenic organisms, this response is required for effective transition from a saprophytic lifestyle to the establishment of pathogenic interactions within a susceptible host. Hyperosmotic stress has been used as a model to study signal transduction and seems to cause many cellular adaptations, including the alteration of protein expression and cellular volume as well as size regulation. In this work, we evaluated the proteomic profile of Paracoccidioides lutzii Pb01 yeast cells during osmotic stress induced by potassium chloride. We performed a high accuracy proteomic technique (NanoUPLC-MS(E)) to identify differentially expressed proteins during osmotic shock. The data describe an osmoadaptative response of this fungus when subjected to this treatment. Proteins involved in the synthesis of cell wall components were modulated, which suggested cell wall remodeling. In addition, alterations in the energy metabolism were observed. Furthermore, proteins involved in amino acid metabolism and hydrogen peroxide detoxification were modulated during osmotic stress. Our study suggests that P. lutzii Pb01. presents a vast osmoadaptative response that is composed of different proteins that act together to minimize the effects caused by osmotic stress. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Arabidopsis decuple mutant reveals the importance of SnRK2 kinases in osmotic stress responses in vivo

    KAUST Repository

    Fujii, Hiroaki

    2011-01-10

    Osmotic stress associated with drought or salinity is a major factor that limits plant productivity. Protein kinases in the SNF1-related protein kinase 2 (SnRK2) family are activated by osmotic stress, suggesting that the kinases are involved in osmotic stress signaling. However, due to functional redundancy, their contribution to osmotic stress responses remained unclear. In this report, we constructed an Arabidopsis line carrying mutations in all 10 members of the SnRK2 family. The decuple mutant snrk2.1/2/3/4/5/6/7/8/9/10 grew poorly under hyperosmotic stress conditions but was similar to the wild type in culture media in the absence of osmotic stress. The mutant was also defective in gene regulation and the accumulation of abscisic acid (ABA), proline, and inositol 1,4,5-trisphosphate under osmotic stress. In addition, analysis of mutants defective in the ABA-activated SnRK2s (snrk2.2/3/6) and mutants defective in the rest of the SnRK2s (snrk2.1/4/5/7/8/9/10) revealed that SnRK2s are a merging point of ABA-dependent and -independent pathways for osmotic stress responses. These results demonstrate critical functions of the SnRK2s in mediating osmotic stress signaling and tolerance.

  13. Temperature and pressure dependent osmotic pressure in liquid sodium-cesium alloys

    International Nuclear Information System (INIS)

    Rashid, R.I.M.A.

    1987-01-01

    The evaluation of the osmotic pressure in terms of the concentration fluctuations of mixtures and the equations of state of the pure liquids is considered. The temperature and pressure dependent experimentally measured concentration-concentration correlations in the long wavelength limit of liquid sodium-cesium alloys are used to demonstrate the appreciable dependence of the temperature and pressure on the osmotic pressure as a function of concentration. Introducing interchange energies as functions of temperature and pressure, our analysis is consistent with the Flory model. Thus, a formalism for evaluating the state dependent osmotic pressure is developed and our numerical work is considered to be an extension of the calculations of Rashid and March in the sense that a temperature and pressure dependent interchange energy parameter that more closely parameterizes the state dependent concentration fluctuations in the liquid alloys, is used. (author)

  14. In vitro screening of potato genotypes for osmotic stress tolerance

    Directory of Open Access Journals (Sweden)

    Gelmesa Dandena

    2017-02-01

    Full Text Available Potato (Solanum tuberosum L. is a cool season crop which is susceptible to both drought and heat stresses. Lack of suitable varieties of the crop adapted to drought-prone areas of the lowland tropics deprives farmers living in such areas the opportunity to produce and use the crop as a source of food and income. As a step towards developing such varieties, the present research was conducted to evaluate different potato genotypes for osmotic stress tolerance under in vitro conditions and identify drought tolerant genotypes for future field evaluation. The experiment was carried out at the Leibniz University of Hannover, Germany, by inducing osmotic stress using sorbitol at two concentrations (0.1 and 0.2 M in the culture medium. A total of 43 genotypes collected from different sources (27 advanced clones from CIP, nine improved varieties, and seven farmers’ cultivars were used in a completely randomized design with four replications in two rounds. Data were collected on root and shoot growth. The results revealed that the main effects of genotype, sorbitol treatment, and their interactions significantly (P < 0.01 influenced root and shoot growthrelated traits. Under osmotic stress, all the measured root and shoot growth traits were significantly correlated. The dendrogram obtained from the unweighted pair group method with arithmetic mean allowed grouping of the genotypes into tolerant, moderately tolerant, and susceptible ones to a sorbitol concentration of 0.2 M in the culture medium. Five advanced clones (CIP304350.100, CIP304405.47, CIP392745.7, CIP388676.1, and CIP388615.22 produced shoots and rooted earlier than all other genotypes, with higher root numbers, root length, shoot and root mass under osmotic stress conditions induced by sorbitol. Some of these genotypes had been previously identified as drought-tolerant under field conditions, suggesting the capacity of the in vitro evaluation method to predict drought stress tolerant

  15. A view on thermodynamics of concentrated electrolytes: Modification necessity for electrostatic contribution of osmotic coefficient

    Science.gov (United States)

    Sahu, Jyoti; Juvekar, Vinay A.

    2018-05-01

    Prediction of the osmotic coefficient of concentrated electrolytes is needed in a wide variety of industrial applications. There is a need to correctly segregate the electrostatic contribution to osmotic coefficient from nonelectrostatic contribution. This is achieved in a rational way in this work. Using the Robinson-Stokes-Glueckauf hydrated ion model to predict non-electrostatic contribution to the osmotic coefficient, it is shown that hydration number should be independent of concentration so that the observed linear dependence of osmotic coefficient on electrolyte concentration in high concentration range could be predicted. The hydration number of several electrolytes (LiCl, NaCl, KCl, MgCl2, and MgSO4) has been estimated by this method. The hydration number predicted by this model shows correct dependence on temperature. It is also shown that the electrostatic contribution to osmotic coefficient is underpredicted by the Debye-Hückel theory at concentration beyond 0.1 m. The Debye-Hückel theory is modified by introducing a concentration dependent hydrated ionic size. Using the present analysis, it is possible to correctly estimate the electrostatic contribution to the osmotic coefficient, beyond the range of validation of the D-H theory. This would allow development of a more fundamental model for electrostatic interaction at high electrolyte concentrations.

  16. Controlled release of glaucocalyxin - a self-nanoemulsifying system from osmotic pump tablets with enhanced bioavailability.

    Science.gov (United States)

    Yanfei, Miao; Guoguang, Chen; Lili, Ren; Pingkai, Ouyang

    2017-03-01

    The purpose of this study was to develop a new formulation to enhance the bioavailability simultaneously with controlled release of glaucocalyxin A (GLA). In this study, controlled release of GLA was achieved by the osmotic release strategy taking advantage of the bioavailability enhancing capacity of self-nanoemulsifying drug delivery systems (SNEDDS). The formulation of GLA-SNEDDS was selected by the solubility and pseudoternary-phase diagrams studies. The prepared GLA-SNEDDS formulations were characterized for self-emulsification time, effect of pH and robustness to dilution, droplet size analysis and zeta potential. The optimized GLA-SNEDDS were used to prepare GLA-SNEDDS osmotic pump tablet via direct powder compression method. The effect of formulation variables on the release characteristic was investigated. GLA-SNEDDS osmotic pump tablets were administered to beagle dogs and their pharmacokinetics were compared to GLA and GLA-SNEDDS as a control. In vitro drug release studies indicated that the GLA-SNEDDS osmotic pump tablet showed sustained release profiles with 90% released within 12 h. Pharmacokinetic study showed steady blood GLA with prolonged T max and mean residence time (MRT), and enhanced bioavailability for GLA-SNEDDS osmotic pump tablet. It was concluded that simultaneous controlling on GLA release and enhanced bioavailability had been achieved by a combination of osmotic pump tablet and SNEDDS.

  17. Comparison of Seed Germination and Recovery Responses of a Salt Marsh Halophyte Halopeplis Perfoliata to Osmotic and Ionic Treatments

    International Nuclear Information System (INIS)

    Rasool, S. G.; Hameed, A.; Ahmed, M. Z.; Khan, M. A.

    2016-01-01

    Salinity affects seed germination of halophytes by inducing ionic toxicity, osmotic constraint or both. Information about the effects of salinity on seed germination of a large number of halophytes exists, but generally little is known about the basis of salinity-induced germination inhibition. In order to partition salinity effects, we studied seed germination and recovery responses of a coastal salt marsh halophyte halopeplis perfoliata to different isotonic treatments (Psi/sub S/: -0.5, -1.0, -1.5, -2.0 and -2.5, MPa) of various salts and polythylene glycol (PEG) under two light regimes (12-h light photo period and 24-h complete darkness). Highest seed germination was observed in distilled water under 12-h light photo period and reduction in osmotic potential of the solution decreased seed germination. However, some seeds of H. perfoliata could germinate in as low as -2.5 MPa (600 mM NaCl), which is equivalent to seawater salinity. Sea-salt treatment was more inhibitory than isotonic NaCl at the lowest osmotic potential (Psi/sub S/ -2.5 MPa). Generally, chloride salts with lowest Psi/sub S/ inhibited germination more than the isotonic sulfate salts. Comparable germination responses of the seeds in NaCl and isotonic PEG treatments as well as high recovery of germination in un-germinated seeds after alleviation of NaCl salinity indicated prevalence of osmotic constraint. These results thus indicate that the seeds of H. perfoliata could tolerate high levels of a wide variety of salts found in soil. (author)

  18. Osmotic heat engine using thermally responsive ionic liquids

    KAUST Repository

    Zhong, Yujiang

    2017-07-11

    The osmotic heat engine (OHE) is a promising technology for converting low grade heat to electricity. Most of the existing studies have focused on thermolytic salt systems. Herein, for the first time, we proposed to use thermally responsive ionic liquids (TRIL) that have either an upper critical solution temperature (UCST) or lower critical solution temperature (LCST) type of phase behavior as novel thermolytic osmotic agents. Closed-loop TRIL-OHEs were designed based on these unique phase behaviors to convert low grade heat to work or electricity. Experimental studies using two UCST-type TRILs, protonated betaine bis(trifluoromethyl sulfonyl)imide ([Hbet][Tf2N]) and choline bis(trifluoromethylsulfonyl)imide ([Choline][Tf2N]) showed that (1) the specific energy of the TRIL-OHE system could reach as high as 4.0 times that of the seawater and river water system, (2) the power density measured from a commercial FO membrane reached up to 2.3 W/m2, and (3) the overall energy efficiency reached up to 2.6% or 18% of the Carnot efficiency at no heat recovery and up to 10.5% or 71% of the Carnet efficiency at 70% heat recovery. All of these results clearly demonstrated the great potential of using TRILs as novel osmotic agents to design high efficient OHEs for recovery of low grade thermal energy to work or electricity.

  19. Fragility and hysteretic creep in frictional granular jamming.

    Science.gov (United States)

    Bandi, M M; Rivera, M K; Krzakala, F; Ecke, R E

    2013-04-01

    The granular jamming transition is experimentally investigated in a two-dimensional system of frictional, bidispersed disks subject to quasistatic, uniaxial compression without vibrational disturbances (zero granular temperature). Three primary results are presented in this experimental study. First, using disks with different static friction coefficients (μ), we experimentally verify numerical results that predict jamming onset at progressively lower packing fractions with increasing friction. Second, we show that the first compression cycle measurably differs from subsequent cycles. The first cycle is fragile-a metastable configuration with simultaneous jammed and unjammed clusters-over a small packing fraction interval (φ(1)disk displacements over the same packing fraction interval. This fragile behavior is explained through a percolation mechanism of stressed contacts where cluster growth exhibits spatial correlation with disk displacements and contributes to recent results emphasizing fragility in frictional jamming. Control experiments show that the fragile state results from the experimental incompatibility between the requirements for zero friction and zero granular temperature. Measurements with several disk materials of varying elastic moduli E and friction coefficients μ show that friction directly controls the start of the fragile state but indirectly controls the exponential pressure rise. Finally, under repetitive loading (compression) and unloading (decompression), we find the system exhibits pressure hysteresis, and the critical packing fraction φ(c) increases slowly with repetition number. This friction-induced hysteretic creep is interpreted as the granular pack's evolution from a metastable to an eventual structurally stable configuration. It is shown to depend on the quasistatic step size Δφ, which provides the only perturbative mechanism in the experimental protocol, and the friction coefficient μ, which acts to stabilize the pack.

  20. Obesity, Food Selectivity, and Physical Activity in Individuals with Fragile X Syndrome

    Science.gov (United States)

    Raspa, Melissa; Bailey, Donald B., Jr.; Bishop, Ellen; Holiday, David; Olmsted, Murrey

    2010-01-01

    National survey data from 884 families were used to examine the overall health of children and adults with fragile X syndrome. Results indicate the rate of obesity in adults with fragile X syndrome is similar to the general population (30%). Male children with fragile X syndrome, however, had higher rates of obesity (31%) when compared with…

  1. Ectodermal dysplasia-skin fragility syndrome: A rare case report

    Directory of Open Access Journals (Sweden)

    Subhash Kashyap

    2015-01-01

    Full Text Available Ectodermal dysplasia/skin fragility syndrome (ED-SFS is a newly described autosomal recessive disorder characterized by skin fragility and blistering, palmoplantar keratoderma, abnormal hair growth, nail dystrophy, and occasionally defective sweating. It results from mutations in the PKP1 gene encoding plakophilin 1 (PKP1, which is an important component of stratifying epithelial desmosomes and a nuclear component of many cell types. Only 12 cases of this rare genodermatosis have been reported so far. We present an unusual case of ED-SFS in a 12-year boy who was normal at birth but subsequently developed skin fragility, hair and nail deformities, abnormal dentition, palmoplantar keratoderma, and abnormal sweating but no systemic abnormality.

  2. Fragility Analysis of Concrete Gravity Dams

    Science.gov (United States)

    Tekie, Paulos B.; Ellingwood, Bruce R.

    2002-09-01

    Concrete gravity dams are an important part ofthe nation's infrastructure. Many dams have been in service for over 50 years, during which time important advances in the methodologies for evaluation of natural phenomena hazards have caused the design-basis events to be revised upwards, in some cases significantly. Many existing dams fail to meet these revised safety criteria and structural rehabilitation to meet newly revised criteria may be costly and difficult. A probabilistic safety analysis (PSA) provides a rational safety assessment and decision-making tool managing the various sources of uncertainty that may impact dam performance. Fragility analysis, which depicts fl%e uncertainty in the safety margin above specified hazard levels, is a fundamental tool in a PSA. This study presents a methodology for developing fragilities of concrete gravity dams to assess their performance against hydrologic and seismic hazards. Models of varying degree of complexity and sophistication were considered and compared. The methodology is illustrated using the Bluestone Dam on the New River in West Virginia, which was designed in the late 1930's. The hydrologic fragilities showed that the Eluestone Dam is unlikely to become unstable at the revised probable maximum flood (PMF), but it is likely that there will be significant cracking at the heel ofthe dam. On the other hand, the seismic fragility analysis indicated that sliding is likely, if the dam were to be subjected to a maximum credible earthquake (MCE). Moreover, there will likely be tensile cracking at the neck of the dam at this level of seismic excitation. Probabilities of relatively severe limit states appear to be only marginally affected by extremely rare events (e.g. the PMF and MCE). Moreover, the risks posed by the extreme floods and earthquakes were not balanced for the Bluestone Dam, with seismic hazard posing a relatively higher risk.

  3. Release and Decay Kinetics of Copeptin vs AVP in Response to Osmotic Alterations in Healthy Volunteers.

    Science.gov (United States)

    Fenske, Wiebke K; Schnyder, Ingeborg; Koch, Gilbert; Walti, Carla; Pfister, Marc; Kopp, Peter; Fassnacht, Martin; Strauss, Konrad; Christ-Crain, Mirjam

    2018-02-01

    Copeptin is the C-terminal fragment of the arginine vasopressin (AVP) prohormone whose measurement is more robust than that of AVP. Similar release and clearance characteristics have been suggested promoting copeptin as a surrogate marker. To characterize the physiology of osmotically regulated copeptin release and its half-life in direct comparison with plasma AVP. Ninety-one healthy volunteers underwent a standardized three-phase test protocol including (1) osmotic stimulation into the hypertonic range by hypertonic-saline infusion followed by osmotic suppression via (2) oral water load and (3) subsequent glucose infusion. Plasma copeptin, AVP, serum sodium, and osmolality levels were measured in regular intervals. In phase 1, an increase in median osmotic pressure [289 (286; 291) to 311 (309; 314) mOsm/kg H2O] caused similar release kinetics of plasma copeptin [4 (3.1; 6) to 29.3 (18.6; 48.2) pmol/L] and AVP [1 (0.7; 1.6) to 10.3 (6.8; 18.8) pg/mL]. Subsequent osmotic suppression to 298 (295; 301) mOsm/kg at the end of phase 3 revealed markedly different decay kinetics between both peptides-an estimated initial half-life of copeptin being approximately 2 times longer than that of AVP (26 vs 12 minutes). Copeptin is released in equimolar amounts with AVP in response to osmotic stimulation, suggesting its high potential as an AVP surrogate for differentiation of osmotic disorders. Furthermore, we here describe the decay kinetics of copeptin in response to osmotic depression enabling to identify a half-life for copeptin in direct comparison with AVP. Copyright © 2017 Endocrine Society

  4. Colloid osmotic pressure in decompensated cirrhosis. A 'mirror image' of portal venous hypertension

    DEFF Research Database (Denmark)

    Henriksen, J H

    1985-01-01

    Colloid osmotic pressure in plasma (IIP) and ascitic fluid (IIA) and hydrostatic pressures in the hepatoportal system were measured simultaneously in 20 patients with decompensated cirrhosis. IIP was significantly decreased (mean, 21 mm Hg, versus normal, 30 mm Hg; P less than 0.01), and IIA...... was significantly below that of plasma (average, 25% of IIP; P less than 0.01). Portal pressure (transmural), determined as wedged hepatic venous minus inferior vena caval pressure (WHV--IVCP), was significantly increased (mean, 18 mm Hg, versus normal, 3 mm Hg; P less than 0.01) and inversely correlated to IIA...

  5. Interaction of prechilling, temperature, osmotic stress, and light in Picea abies seed germination

    International Nuclear Information System (INIS)

    Leinonen, K.; Rita, H.

    1995-01-01

    A multi-factor experimental approach and proportional odds model was used to study interactions between five environmental factors significant to Norway spruce seed germination: prechilling (at +4.5 °C), suboptimal temperatures (+12 and +16 °C), osmotically induced water stress (–0.3 Mpa and 0 Mpa), prolonged white light, and short-period far-red light. Temperature and osmotic stress interacted with one another in the germination of seeds: the effect of osmotic stress being stronger at +16 °C than at +12 °C. In natural conditions, this interaction may prevent germination early in the summer when soil dries and temperature increases. Prolonged white light prevented germination at low temperature and low osmotic potential. Inhibitory effect was less at higher temperatures and higher osmotic potential, as well as after prechilling. Short-period far-red light did not prevent germination of unchilled seeds in darkness. Prechilling tended to make seeds sensitive to short pulses of far-red light, an effect which depended on temperature: at +12 °C the effect on germination was promotive, but at +16 °C, inhibitory and partly reversible by white light. It seems that Norway spruce seeds may have adapted to germinate in canopy shade light rich in far-red. The seeds may also have evolved mechanisms to inhibit germination in prolonged light

  6. Sorbitol treatment extends lifespan and induces the osmotic stress response in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Devon eChandler-Brown

    2015-10-01

    Full Text Available The response to osmotic stress is a highly conserved process for adapting to changing environmental conditions. Prior studies have shown that hyperosmolarity by addition of sorbitol to the growth medium is sufficient to increase both chronological and replicative lifespan in the budding yeast, Saccharomyces cerevisiae. Here we report a similar phenomenon in the nematode Caenorhabditis elegans. Addition of sorbitol to the nematode growth medium induces an adaptive osmotic response and increases C. elegans lifespan by about 35%. Lifespan extension from 5% sorbitol behaves similarly to dietary restriction in a variety of genetic backgrounds, increasing lifespan additively with mutation of daf-2(e1370 and independently of daf-16(mu86, sir-2.1(ok434, aak-2(ok524, and hif-1(ia04. Dietary restriction by bacterial deprivation or mutation of eat-2(ad1113 fails to further extend lifespan in the presence of 5% sorbitol. Two mutants with constitutive activation of the osmotic response, osm-5(p813 and osm-7(n1515, were found to be long-lived, and lifespan extension from sorbitol required the glycerol biosynthetic enzymes GPDH-1 and GPDH-2. Taken together, these observations demonstrate that exposure to sorbitol at levels sufficient to induce an adaptive osmotic response extends lifespan in worms and define the osmotic stress response pathway as a longevity pathway conserved between yeast and nematodes.

  7. Articulation and Noncomprehension Signaling in Adolescent and Adult Males with Down Syndrome and Fragile X Syndrome

    Science.gov (United States)

    Fedak, Larissa Ann

    2012-01-01

    The purpose of this study was to determine whether or not decreased articulation of speech played a role in the ability of an individual with Down syndrome or Fragile X syndrome to signal noncomprehension and whether the two groups differed in their levels of articulation of speech and noncomprehension signaling ability. The research was conducted…

  8. Salinity- and population-dependent genome regulatory response during osmotic acclimation in the killifish (Fundulus heteroclitus) gill.

    Science.gov (United States)

    Whitehead, Andrew; Roach, Jennifer L; Zhang, Shujun; Galvez, Fernando

    2012-04-15

    The killifish Fundulus heteroclitus is abundant in osmotically dynamic estuaries and it can quickly adjust to extremes in environmental salinity. We performed a comparative osmotic challenge experiment to track the transcriptomic and physiological responses to two salinities throughout a time course of acclimation, and to explore the genome regulatory mechanisms that enable extreme osmotic acclimation. One southern and one northern coastal population, known to differ in their tolerance to hypo-osmotic exposure, were used as our comparative model. Both populations could maintain osmotic homeostasis when transferred from 32 to 0.4 p.p.t., but diverged in their compensatory abilities when challenged down to 0.1 p.p.t., in parallel with divergent transformation of gill morphology. Genes involved in cell volume regulation, nucleosome maintenance, ion transport, energetics, mitochondrion function, transcriptional regulation and apoptosis showed population- and salinity-dependent patterns of expression during acclimation. Network analysis confirmed the role of cytokine and kinase signaling pathways in coordinating the genome regulatory response to osmotic challenge, and also posited the importance of signaling coordinated through the transcription factor HNF-4α. These genome responses support hypotheses of which regulatory mechanisms are particularly relevant for enabling extreme physiological flexibility.

  9. Ectodermal Dysplasia Skin Fragility Syndrome

    Directory of Open Access Journals (Sweden)

    Ayça Alan Atalay

    2014-06-01

    Full Text Available Ectodermal dysplasia-skin fragility syndrome (EDSFS is a rare autosomal recessive genodermatosis first described in 1997 by Mc Grath. EDSFS results from loss of function mutations in plakophilin-1 (PKP1. PKP1 is a structural component of desmosomes, cellcell adhesion complexes. It is also found as a nuclear protein in several cell types that are lack of desmosomes. In skin, however, PKP1 expression is confined mainly to suprabasal keratinocytes and the outer root sheath of hair follicules. Loss of function mutation in PKP1 leads to extensive skin fragility, bullae and erosions following minor trauma, focal keratoderma with painful fissures, alopecia, and nail dystrophy. In some patients hypohidrosis may also be seen. EDSFS is now considered as a specific suprabasal form of epidermolysis bullosa simplex. In this report we describe a 20 year old EDSFS case.

  10. Osmotic phenomena in application for hyperbaric oxygen treatment.

    Science.gov (United States)

    Babchin, A; Levich, E; Melamed M D, Y; Sivashinsky, G

    2011-03-01

    Hyperbaric oxygen (HBO) treatment defines the medical procedure when the patient inhales pure oxygen at elevated pressure conditions. Many diseases and all injuries are associated with a lack of oxygen in tissues, known as hypoxia. HBO provides an effective method for fast oxygen delivery in medical practice. The exact mechanism of the oxygen transport under HBO conditions is not fully identified. The objective of this article is to extend the colloid and surface science basis for the oxygen transport in HBO conditions beyond the molecular diffusion transport mechanism. At a pressure in the hyperbaric chamber of two atmospheres, the partial pressure of oxygen in the blood plasma increases 10 times. The sharp increase of oxygen concentration in the blood plasma creates a considerable concentration gradient between the oxygen dissolved in the plasma and in the tissue. The concentration gradient of oxygen as a non-electrolyte solute causes an osmotic flow of blood plasma with dissolved oxygen. In other words, the molecular diffusion transport of oxygen is supplemented by the convective diffusion raised due to the osmotic flow, accelerating the oxygen delivery from blood to tissue. A non steady state equation for non-electrolyte osmosis is solved asymptotically. The solution clearly demonstrates two modes of osmotic flow: normal osmosis, directed from lower to higher solute concentrations, and anomalous osmosis, directed from higher to lower solute concentrations. The fast delivery of oxygen from blood to tissue is explained on the basis of the strong molecular interaction between the oxygen and the tissue, causing an influx of oxygen into the tissue by convective diffusion in the anomalous osmosis process. The transport of the second gas, nitrogen, dissolved in the blood plasma, is also taken into the consideration. As the patient does not inhale nitrogen during HBO treatment, but exhales it along with oxygen and carbon dioxide, the concentration of nitrogen in blood

  11. International Companies in Fragile States

    DEFF Research Database (Denmark)

    Patey, Luke; Kragelund, Peter

    Denmark must not fail to promote corporate social responsibility in fragile states. International companies remain active in these environments, and often worsen rather than alleviate poor governance. Financial transparency and human rights initiatives offer the first step in ensuring...

  12. Robust-yet-fragile nature of interdependent networks

    Science.gov (United States)

    Tan, Fei; Xia, Yongxiang; Wei, Zhi

    2015-05-01

    Interdependent networks have been shown to be extremely vulnerable based on the percolation model. Parshani et al. [Europhys. Lett. 92, 68002 (2010), 10.1209/0295-5075/92/68002] further indicated that the more intersimilar networks are, the more robust they are to random failures. When traffic load is considered, how do the coupling patterns impact cascading failures in interdependent networks? This question has been largely unexplored until now. In this paper, we address this question by investigating the robustness of interdependent Erdös-Rényi random graphs and Barabási-Albert scale-free networks under either random failures or intentional attacks. It is found that interdependent Erdös-Rényi random graphs are robust yet fragile under either random failures or intentional attacks. Interdependent Barabási-Albert scale-free networks, however, are only robust yet fragile under random failures but fragile under intentional attacks. We further analyze the interdependent communication network and power grid and achieve similar results. These results advance our understanding of how interdependency shapes network robustness.

  13. Novel regulation of aquaporins during osmotic stress.

    Science.gov (United States)

    Vera-Estrella, Rosario; Barkla, Bronwyn J; Bohnert, Hans J; Pantoja, Omar

    2004-08-01

    Aquaporin protein regulation and redistribution in response to osmotic stress was investigated. Ice plant (Mesembryanthemum crystallinum) McTIP1;2 (McMIPF) mediated water flux when expressed in Xenopus leavis oocytes. Mannitol-induced water imbalance resulted in increased protein amounts in tonoplast fractions and a shift in protein distribution to other membrane fractions, suggesting aquaporin relocalization. Indirect immunofluorescence labeling also supports a change in membrane distribution for McTIP1;2 and the appearance of a unique compartment where McTIP1;2 is expressed. Mannitol-induced redistribution of McTIP1;2 was arrested by pretreatment with brefeldin A, wortmannin, and cytochalasin D, inhibitors of vesicle trafficking-related processes. Evidence suggests a role for glycosylation and involvement of a cAMP-dependent signaling pathway in McTIP1;2 redistribution. McTIP1;2 redistribution to endosomal compartments may be part of a homeostatic process to restore and maintain cellular osmolarity under osmotic-stress conditions.

  14. Osmotic Gradients Induce Bio-reminiscent Morphological Transformations in Giant Unilamellar Vesicles

    Directory of Open Access Journals (Sweden)

    Kamila eOglecka

    2012-05-01

    Full Text Available We report observations of large-scale, in-plane and out-of-plane membrane deformations in giant uni- and multilamellar vesicles composed of binary and ternary lipid mixtures in the presence of net transvesicular osmotic gradients. The lipid mixtures we examined consisted of binary mixtures of DOPC and DPPC lipids and ternary mixtures comprising POPC, sphingomyelin, and cholesterol over a range of compositions – both of which produce co-existing phases for selected ranges of compositions at room temperature under thermodynamic equilibrium. In the presence of net osmotic gradient, we find that the in-plane phase separation potential of these mixtures is non-trivially altered and a variety of out-of-plane morphological remodeling occurs. The repertoire of membrane deformations we observe display striking resemblance to their biological counterparts in live cells encompassing vesiculation, membrane fission and fusion, tubulation and pearling, as well as expulsion of entrapped vesicles from multicompartmental GUV architectures through large, self-healing transient pores. These observations suggest that the forces introduced by simple osmotic gradients across membrane boundaries could act as a trigger for shape-dependent membrane and vesicle trafficking activities. We speculate that such coupling of osmotic gradients with membrane properties might have provided lipid-mediated mechanisms during the early evolution of membrane compartmentalization in the absence of osmoregulatory protein machinery.

  15. Osmotic therapies added to antibiotics for acute bacterial meningitis

    Science.gov (United States)

    Wall, Emma Cb; Ajdukiewicz, Katherine Mb; Bergman, Hanna; Heyderman, Robert S; Garner, Paul

    2018-01-01

    Background Every day children and adults die from acute community-acquired bacterial meningitis, particularly in low-income countries, and survivors risk deafness, epilepsy and neurological disabilities. Osmotic therapies may attract extra-vascular fluid and reduce cerebral oedema, and thus reduce death and improve neurological outcomes. This is an update of a Cochrane Review first published in 2013. Objectives To evaluate the effects of osmotic therapies added to antibiotics for acute bacterial meningitis in children and adults on mortality, deafness and neurological disability. Search methods We searched CENTRAL (2017, Issue 1), MEDLINE (1950 to 17 February 2017), Embase (1974 to 17 February 2017), CINAHL (1981 to 17 February 2017), LILACS (1982 to 17 February 2017) and registers of ongoing clinical trials (ClinicalTrials.com, WHO ICTRP) (21 February 2017). We also searched conference abstracts and contacted researchers in the field (up to 12 December 2015). Selection criteria Randomised controlled trials testing any osmotic therapy in adults or children with acute bacterial meningitis. Data collection and analysis Two review authors independently screened the search results and selected trials for inclusion. Results are presented using risk ratios (RR) and 95% confidence intervals (CI) and grouped according to whether the participants received steroids or not. We used the GRADE approach to assess the certainty of the evidence. Main results We included five trials with 1451 participants. Four trials evaluated glycerol against placebo, and one evaluated glycerol against 50% dextrose; in addition three trials evaluated dexamethasone and one trial evaluated acetaminophen (paracetamol) in a factorial design. Stratified analysis shows no effect modification with steroids; we present aggregate effect estimates. Compared to placebo, glycerol probably has little or no effect on death in people with bacterial meningitis (RR 1.08, 95% CI 0.90 to 1.30; 5 studies, 1272

  16. Epidemiology of "fragile skin": results from a survey of different skin types

    Directory of Open Access Journals (Sweden)

    Haftek M

    2013-12-01

    Full Text Available Marek Haftek,1 Christine Coutanceau,2 Charles Taïeb3 1Université Lyon 1, Laboratoire de Recherche Dermatologique, Faculté de Médecine et de Pharmacie, Lyon, 2Département Médical, Laboratoires Dermatologiques A-Derma, Lavaur, 3Public Health, Pierre Fabre SA, Paris, France Background: Epidemiologic information regarding the prevalence of "fragile skin" in different adult populations is currently limited. The objective of the current survey was to assess the occurrence of perceived "fragile skin" across different skin types in the general adult population. Methods: Individuals aged 15–65 years from five representative geographic regions (France, Spain, Sweden, Japan, and the US were interviewed and grouped into the following skin types: Caucasian North skin (n=1,218, Caucasian South skin (n=1,695, Asian skin (n=1,500, and Black skin (n=500. The main survey question was "In your opinion, do you have fragile skin?" Concepts relating to the nature and appearance of an individual's skin were also evaluated. Results: A total of 4,913 individuals were interviewed. Subjects in the Caucasian North, Caucasian South, Asian, and Black skin type groups responded positively to the question "In your opinion, do you have fragile skin?" in the following proportions: 24.44%, 29.71%, 52.67%, and 42.20%, respectively. With the exception of individuals in the Black skin group, "fragile skin" was prevalent in significantly more women than men (P<0.0001. Compared with other age categories, the prevalence of "fragile skin" was significantly higher in individuals aged 15–34 years (P<0.0001, regardless of skin type. In general, individuals reporting "fragile skin" were 2–3-fold more likely to respond positively to a series of questions relating to the nature and appearance of their skin. The prevalence of "fragile skin" was also higher in individuals who experienced dermatosis (skin lesions of any type in the previous 12 months. Conclusion: Whilst these

  17. Optimization of Vacuum Frying Parameters in Combination with Osmotic Dehydration of Kiwi Slices to Produce Healthy Product

    Directory of Open Access Journals (Sweden)

    Fatemeh Aghabozorg Afjeh Aghabozorg Afjeh

    2014-05-01

    Full Text Available Osmotic dehydration under discontinuous reduced pressure is one of the new methods of preparation fruits and vegetable processing with in view of good health. Processing of foods at high temperatures used to cook them can cause the formation of carcinogenic substances like acrylamide, and this risk remains even if the trans-fat is removed. The low temperatures employed in this method resulted in the products with the desired texture, nutritional, and colour. The purpose of this research was evaluation of the variable effects of osmotic dehydration process (ambient pressure, contact time of product and solution, concentration and temperature of osmotic solution on the quality factors of product (colour changes, texture, moisture, oil uptake, and water loss to solid gain ratio and achieving the optimum process conditions. Studying the quality parameters of the product, the temperature range of osmotic solution, pressure, concentration of the osmotic solution and contact time of product and solution were assumed as 30 to 50°C, 500 to 700 mbar, 30 to 50% and 60 to 180 min, respectively. The test plans involving 31 tests were obtained by using response surface statistical models and central composite design. They were fried at the condition of 108ºC, 8 min and 320 mbar by using statistical correlations, 48.71ºC for the osmotic solution temperature, 592.07 mbar for the pressure, 62.92 min for the time and 34.87% for the osmotic solution. Concentrations were obtained as optimum conditions of osmotic dehydration of kiwi slices under reduced pressure. In summary combination of osmotic dehydration and vacuum frying improved the quality of the final fried kiwi, so this method is recommended for production of healthy products.

  18. Rescue of Synaptic Phenotypes and Spatial Memory in Young Fragile X Mice.

    Science.gov (United States)

    Sun, Miao-Kun; Hongpaisan, Jarin; Alkon, Daniel L

    2016-05-01

    Fragile X syndrome (FXS) is characterized by synaptic immaturity, cognitive impairment, and behavioral changes. The disorder is caused by transcriptional shutdown in neurons of thefragile X mental retardation 1gene product, fragile X mental retardation protein. Fragile X mental retardation protein is a repressor of dendritic mRNA translation and its silencing leads to dysregulation of synaptically driven protein synthesis and impairments of intellect, cognition, and behavior, and FXS is a disorder that currently has no effective therapeutics. Here, young fragile X mice were treated with chronic bryostatin-1, a relatively selective protein kinase Cεactivator, which induces synaptogenesis and synaptic maturation/repair. Chronic treatment with bryostatin-1 rescues young fragile X mice from the disorder phenotypes, including normalization of most FXS abnormalities in 1) hippocampal brain-derived neurotrophic factor expression, 2) postsynaptic density-95 levels, 3) transformation of immature dendritic spines to mature synapses, 4) densities of the presynaptic and postsynaptic membranes, and 5) spatial learning and memory. The therapeutic effects were achieved without downregulation of metabotropic glutamate receptor (mGluR) 5 in the hippocampus and are more dramatic than those of a late-onset treatment in adult fragile X mice. mGluR5 expression was in fact lower in fragile X mice and its expression was restored with the bryostatin-1 treatment. Our results show that synaptic and cognitive function of young FXS mice can be normalized through pharmacological treatment without downregulation of mGluR5 and that bryostatin-1-like agents may represent a novel class of drugs to treat fragile X mental retardation at a young age and in adults. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  19. Osmotic coefficients of water for thorium nitrate solutions at 25, 37, and 50oC

    International Nuclear Information System (INIS)

    Lemire, R.J.; Sagert, N.H.; Lau, D.W.P.

    1983-01-01

    Vapor pressure osmometry was used to measure osmotic coefficients of water for thorium nitrate solutions at 25, 37, and 50 o C and at molalities up to 0.2 mol·kg -1 . The data were fitted to three- and four-parameter equations containing limiting-law terms for a 4:1 electrolyte. The variation of the osmotic coefficients as a function of temperature was found to be small. The results are compared to published values for the osmotic coefficients. (author)

  20. Survey of seismic fragilities used in PRA studies of nuclear power plants

    International Nuclear Information System (INIS)

    Park, Y.J.; Hofmayer, C.H.; Chokshi, N.C.

    1998-01-01

    In recent years, seismic PRA studies have been performed on a large number of nuclear power plants in the USA. This paper presents a summary of a survey on fragility databases and the range of evaluated fragility values of various equipment categories based on past PRAs. The survey includes the use of experience data, the interpretations of available test data, and the quantification of uncertainties. The surveyed fragility databases are limited to data available in the public domain such as NUREG reports, conference proceedings and other publicly available reports. The extent of the availability of data as well as limitations are studied and tabulated for various equipment categories. The survey of the fragility values in past PRA studies includes not only the best estimate values, but also the dominant failure modes and the estimated uncertainty levels for each equipment category. The engineering judgments employed in estimating the uncertainty in the fragility values are also studied. This paper provides a perspective on the seismic fragility evaluation procedures for equipment in order to clearly identify the engineering analysis and judgment used in past seismic PRA studies

  1. Fragility: The Next Wave in Critical Infrastructure Protection

    OpenAIRE

    Allan McDougall

    2009-01-01

    In North America today, we are about to embark on a significant effort to repair, or even upgrade, many aspects of our infrastructure. Many of these efforts are linked to economic recovery packages. Others are based on sheer need. The challenge for decision makers and planners involves ensuring that scarce economic resources are put to their best use. Understanding the concept of fragility plays a pivotal part in reaching that understanding.Fragility, like many other systems—particularly Info...

  2. Mathematical Definition, Mapping, and Detection of (Anti)Fragility

    OpenAIRE

    Taleb, Nassim N.; Douady, Raphael

    2012-01-01

    URL des Documents de travail : http://centredeconomiesorbonne.univ-paris1.fr/documents-de-travail/; Documents de travail du Centre d'Economie de la Sorbonne 2014.93 - ISSN : 1955-611X; We provide a mathematical definition of fragility and antifragility as negative or positive sensitivity to a semi-measure of dispersion and volatility (a variant of negative or positive "vega") and examine the link to nonlinear effects. We integrate model error (and biases) into the fragile or antifragile conte...

  3. A numerical method for osmotic water flow and solute diffusion with deformable membrane boundaries in two spatial dimension

    Science.gov (United States)

    Yao, Lingxing; Mori, Yoichiro

    2017-12-01

    Osmotic forces and solute diffusion are increasingly seen as playing a fundamental role in cell movement. Here, we present a numerical method that allows for studying the interplay between diffusive, osmotic and mechanical effects. An osmotically active solute obeys a advection-diffusion equation in a region demarcated by a deformable membrane. The interfacial membrane allows transmembrane water flow which is determined by osmotic and mechanical pressure differences across the membrane. The numerical method is based on an immersed boundary method for fluid-structure interaction and a Cartesian grid embedded boundary method for the solute. We demonstrate our numerical algorithm with the test case of an osmotic engine, a recently proposed mechanism for cell propulsion.

  4. Fabrication and transfer of fragile 3D PDMS microstructures

    International Nuclear Information System (INIS)

    Karlsson, J Mikael; Haraldsson, Tommy; Carlborg, Carl Fredrik; Van der Wijngaart, Wouter; Hansson, Jonas; Russom, Aman

    2012-01-01

    We present a method for PDMS microfabrication of fragile membranes and 3D fluidic networks, using a surface modified water-dissolvable release material, poly(vinyl alcohol), as a tool for handling, transfer and release of fragile polymer microstructures. The method is well suited for the fabrication of complex multilayer microfluidic devices, here shown for a PDMS device with a thin gas permeable membrane and closely spaced holes for vertical interlayer connections fabricated in a single layer. To the authors’ knowledge, this constitutes the most advanced PDMS fabrication method for the combination of thin, fragile structures and 3D fluidics networks, and hence a considerable step in the direction of making PDMS fabrication of complex microfluidic devices a routine endeavour. (paper)

  5. Fragility Variation of Lithium Borate Glasses Studied by Temperature-Modulated DSC

    Science.gov (United States)

    Matsuda, Yu; Fukawa, Yasuteru; Kawashima, Mitsuru; Kojima, Seiji

    2008-02-01

    The fragility of lithium borate glass system has been investigated by Temperature-Modulated Differential Scanning Calorimetry (TMDSC). The frequency and temperature dependences of dynamic specific heat have been observed in the vicinity of a glass transition temperature Tg. It is shown that the value of the fragility index m can be determined from the temperature dependence of the α-relaxation times observed by TMDSC, when the raw phase angle is properly corrected. The composition dependence of the fragility has been also discussed.

  6. Fragility non-hip fracture patients are at risk.

    Science.gov (United States)

    Gosch, M; Druml, T; Nicholas, J A; Hoffmann-Weltin, Y; Roth, T; Zegg, M; Blauth, M; Kammerlander, C

    2015-01-01

    Fragility fractures are a growing worldwide health care problem. Hip fractures have been clearly associated with poor outcomes. Fragility fractures of other bones are common reasons for hospital admission and short-term disability, but specific long-term outcome studies of non-hip fragility fractures are rare. The aim of our trial was to evaluate the 1-year outcomes of non-hip fragility fracture patients. This study is a retrospective cohort review of 307 consecutive older inpatient non-hip fracture patients. Patient data for analysis included fracture location, comorbidity prevalence, pre-fracture functional status, osteoporosis treatments and sociodemographic characteristics. The main outcomes evaluated were 1-year mortality and post-fracture functional status. As compared to the expected mortality, the observed 1-year mortality was increased in the study group (17.6 vs. 12.2 %, P = 0.005). After logistic regression, three variables remained as independent risk factors for 1-year mortality among non-hip fracture patients: malnutrition (OR 3.3, CI 1.5-7.1), Charlson comorbidity index (CCI) (OR 1.3, CI 1.1-1.5) and the Parker Mobility Score (PMS) (OR 0.85, CI 0.74-0.98). CCI and PMS were independent risk factors for a high grade of dependency after 1 year. Management of osteoporosis did not significantly improve after hospitalization due to a non-hip fragility fracture. The outcomes of older non-hip fracture patients are comparable to the poor outcomes of older hip fracture patients, and appear to be primarily related to comorbidities, pre-fracture function and nutritional status. The low rate of patients on osteoporosis medications likely reflects the insufficient recognition of the importance of osteoporosis assessment and treatment in non-hip fracture patients. Increased clinical and academic attention to non-hip fracture patients is needed.

  7. The osmotic pressure of 3He-4He mixtures along the phase separation curve

    NARCIS (Netherlands)

    van de Klundert, L.J.M.; Bos, M.R.E.; van der Meij, J.A.M.; Steffens, H.A.

    1977-01-01

    The osmotic pressure of 3He-4He mixtures was measured along the phase separation curve at temperatures up to 500 mK by balancing it with the fountain pressure of pure 4He. The usefullness of the secondary osmotic pressure thermometer was reinvestigated.

  8. The osmotic pressure of 3He-4He mixtures along the phase separation curve

    International Nuclear Information System (INIS)

    Klundert, L.J.M. van de; Bos, M.R.E.; Meij, J.A.M. van der; Steffens, H.A.

    1977-01-01

    The osmotic pressure of 3 He- 4 He mixtures was measured along the phase separation curve at temperatures up to 500 mK by balancing it with the fountain pressure of pure 4 He. The usefullness of the secondary osmotic pressure thermometer was reinvestigated. (Auth.)

  9. Risk factors for fragility fracture in Seremban district, Malaysia: a comparison of patients with fragility fracture in the orthopedic ward versus those in the outpatient department.

    Science.gov (United States)

    Keng Yin Loh; King Hock Shong; Soo Nie Lan; Lo, Wan-Yi; Shu Yuen Woon

    2008-01-01

    Osteoporosis is a silent disease and becomes clinically significant in the presence of fragility fracture. Identifying risk factors that are associated with osteoporosis in the community is important in reducing the incidence of fragility fracture. The aim of this study is to identify risk factors associated with fragility fracture in the Seremban District of Malaysia. This is a population comparison study between orthopedic ward patients and outpatients attending a community health clinic for 6 months. Epidemiological data and the possible risk factors for osteoporosis were collected by direct interview. This study demonstrates that advancing age, low body weight, smoking, lack of regular exercise, low consumption of calcium containing foods, and using bone depleting drugs (steroids, thyroid hormone, and frusemides) are major risk factors for fragility fracture. Most of these risk factors are modifiable through effective lifestyle intervention.

  10. Osmotically-driven membrane processes for water reuse and energy recovery

    Science.gov (United States)

    Achilli, Andrea

    Osmotically-driven membrane processes are an emerging class of membrane separation processes that utilize concentrated brines to separate liquid streams. Their versatility of application make them an attractive alternative for water reuse and energy production/recovery. This work focused on innovative applications of osmotically-driven membrane processes. The novel osmotic membrane bioreactor (OMBR) system for water reuse was presented. Experimental results demonstrated high sustainable flux and relatively low reverse diffusion of solutes from the draw solution into the mixed liquor. Membrane fouling was minimal and controlled with osmotic backwashing. The OMBR system was found to remove greater than 99% of organic carbon and ammonium-nitrogen. Forward osmosis (FO) can employ different draw solution in its process. More than 500 inorganic compounds were screened as draw solution candidates, the desktop screening process resulted in 14 draw solutions suitable for FO applications. The 14 draw solutions were then tested in the laboratory to evaluate water flux and reverse salt diffusion through the membrane. Results indicated a wide range of water flux and reverse salt diffusion depending on the draw solution utilized. Internal concentration polarization was found to lower both water flux and reverse salt diffusion by reducing the draw solution concentration at the interface between the support and dense layer of the membrane. A small group of draw solutions was found to be most suitable for FO processes with currently available FO membranes. Another application of osmotically-driven membrane processes is pressure retarded osmosis (PRO). PRO was investigated as a viable source of renewable energy. A PRO model was developed to predict water flux and power density under specific experimental conditions. The predictive model was tested using experimental results from a bench-scale PRO system. Previous investigations of PRO were unable to verify model predictions due to

  11. Clinical aspects of the fragile X syndrome.

    Science.gov (United States)

    Brown, W Ted

    2012-01-01

    Fragile X syndrome patients express a wide array of cognitive and other gender-specific phenotypic features. These manifestations result not only from molecular mechanisms that are altered as a result of the expansion of a CGG-repeat region in the FMR1 promoter, but also genetic factors such as founder effects and mosaicism. In this chapter, I will summarize the many and varied features of fragile X syndrome as they present themselves in a clinical setting and describe the procedures that are used to diagnose patients. Finally, I will briefly touch on recent developments that will affect patient screening in the future.

  12. The World Bank and Fragile States: Dynamics of Cooperation and Aid Structure

    Directory of Open Access Journals (Sweden)

    Solomatin A.

    2018-03-01

    Full Text Available The eradication of extreme poverty in fragile states is one of the central problems of global governance at the present time. Development of these states is hindered by instability, weak public and social institutions or ongoing conflicts and violence. The World Bank is a key partner of fragile states, which account for almost a third of the world’s population. This article is a continuation of research exploring the evolution of conceptual and practical approaches by the World Bank to cooperation with fragile states. Its methodology is based on a multilevel analysis of the securitization of foreign aid as proposed by J. Lind and J. Howell of the London School of Economics. The main focus of this examination is on the dynamics of the change of scale and structure of the World Bank’s aid to fragile states in comparison with global armed trends of providing aid to fragile states as well. This article concludes that statements about the priority of the Bank’s work in fragile states have not yet been realized in practice. The Bank remains committed to the standard approach to working with this group of recipients, which involves serious risks. The World Bank leans toward supporting projects in fragile states which increases volatility and reduces aid predictability. This trend undermines the development potentials of recipient states. Attention is drawn to political factors influencing aid flows to fragile states and particularly to the tendency of increasing the share of aid provided to fragile states through multi donor trust funds rather than through the mechanisms of the International Development Association (IDA. This trend indicates that the Bank is no longer a central point of aid distribution to the recipients, pointing to the lack of trust of donor states in the existing mechanisms and rules of aid distribution. It also reveals the expanding role of donors’ strategic interests in the process of choosing recipients of World Bank aid.

  13. Sugar beet molasses: Properties and applications in osmotic dehydration of fruits and vegetables

    Directory of Open Access Journals (Sweden)

    Šarić Ljubiša Ć.

    2016-01-01

    Full Text Available Molasses is an important by-product of sugar beet or sugar cane refining industry and it was one of the first sweeteners used in human nutrition. Sugar cane molasses has unique characteristics that can make it suitable for application in food industry, especially in confectionery and bakery products. On the other hand, sugar beet molasses has not had greater application in the human diet, primarily because of its strong smell and taste of the beet, which makes it unattractive for consumption. Since recent investigations showed that sugar beet molasses can be used as a hypertonic solution in osmotic dehydration of different materials of plant and animal origin, the objective of this work was to review recently studied sugar beet molasses in terms of its applications in osmotic dehydrations of fruits and vegetables. Previous studies showed that sugar beet molasses is an excellent medium for osmotic dehydration of fruits and vegetables (apple, carrot, plum, etc. primarily due to a high content of dry matter (80%, w/w and specific nutrient content. An important advantage of using sugar beet molasses as a hypertonic solution is an enrichment of the dehydrated material in minerals and vitamins, which penetrate from molasses into the plant tissue. Concentration of sugar beet molasses solution and immersion time had the biggest influence on the process of osmotic dehydration of fruit and vegetables, while the temperature of the solution was the least influential parameter. The effect of immersion time on the kinetics of osmotic dehydration in sugar beet molasses increases with an increase in concentration of hypertonic solution. Fruit and vegetables dehydrated in sugar beet molasses had a higher dry matter content compared to samples treated in sucrose solutions. Besides, application of sugar beet molasses in osmotic dehydration of fruits and vegetables had some other advantages such as lower cost of molasses compared to sugar and its liquid aggregate

  14. Heart Activity and Autistic Behavior in Infants and Toddlers with Fragile X Syndrome

    Science.gov (United States)

    Roberts, Jane E.; Tonnsen, Bridgette; Robinson, Ashley; Shinkareva, Svetlana V.

    2012-01-01

    The present study contrasted physiological arousal in infants and toddlers with fragile X syndrome to typically developing control participants and examined physiological predictors early in development to autism severity later in development in fragile X syndrome. Thirty-one males with fragile X syndrome (ages 8-40 months) and 25 age-matched…

  15. The Fragile X Protein binds mRNAs involved in cancer progression and modulates metastasis formation

    Science.gov (United States)

    Lucá, Rossella; Averna, Michele; Zalfa, Francesca; Vecchi, Manuela; Bianchi, Fabrizio; Fata, Giorgio La; Del Nonno, Franca; Nardacci, Roberta; Bianchi, Marco; Nuciforo, Paolo; Munck, Sebastian; Parrella, Paola; Moura, Rute; Signori, Emanuela; Alston, Robert; Kuchnio, Anna; Farace, Maria Giulia; Fazio, Vito Michele; Piacentini, Mauro; De Strooper, Bart; Achsel, Tilmann; Neri, Giovanni; Neven, Patrick; Evans, D Gareth; Carmeliet, Peter; Mazzone, Massimiliano; Bagni, Claudia

    2013-01-01

    The role of the fragile X mental retardation protein (FMRP) is well established in brain, where its absence leads to the fragile X syndrome (FXS). FMRP is almost ubiquitously expressed, suggesting that, in addition to its effects in brain, it may have fundamental roles in other organs. There is evidence that FMRP expression can be linked to cancer. FMR1 mRNA, encoding FMRP, is overexpressed in hepatocellular carcinoma cells. A decreased risk of cancer has been reported in patients with FXS while a patient-case with FXS showed an unusual decrease of tumour brain invasiveness. However, a role for FMRP in regulating cancer biology, if any, remains unknown. We show here that FMRP and FMR1 mRNA levels correlate with prognostic indicators of aggressive breast cancer, lung metastases probability and triple negative breast cancer (TNBC). We establish that FMRP overexpression in murine breast primary tumours enhances lung metastasis while its reduction has the opposite effect regulating cell spreading and invasion. FMRP binds mRNAs involved in epithelial mesenchymal transition (EMT) and invasion including E-cadherin and Vimentin mRNAs, hallmarks of EMT and cancer progression. PMID:24092663

  16. Raman and DSC studies of fragility in tellurium-zinc oxide glass formers

    International Nuclear Information System (INIS)

    Stavrou, Elissaios; Kripotou, Sotiria; Raptis, Constantine; Turrell, Sylvia; Syassen, Karl

    2011-01-01

    Raman scattering and differential scanning calorimetry (DSC) measurements have been carried out in four mixed (TeO 2 ) 1-x (ZnO) x (x = 0.1, 0.2, 0.3, 0.4) glasses at high temperatures (Raman and DSC through the glass transition) and high pressures (Raman) with the aim of determining the fragility of these glass forming oxides. Four different criteria, corresponding to four parameters, were applied to assess the fragility of the glasses. From the DSC studies, we have obtained the fragility parameter m which corresponds to the slopes of Arrhenius (lnQ vs. 1/T g , were Q is the heating rate) plots, and the glass transition width ΔT g . Also, from the low-frequency Raman scattering, and in particular the boson peak intensity of the glasses at T g , we have estimated the fragility ratio r R (T g ) = I min /I max whose value serves as another (empirical) fragility criterion. Finally, from high pressure Raman measurements on the glasses, we have estimated the Grueneisen parameter γ T for each glass, which constitutes the fourth fragility parameter adopted in this work. Considering the four parameters ΔT g , m, r (T g ) and γ T and the generally accepted (empirical) fragility criteria, we conclude that the mixed tellurium-zinc oxides constitute strong-to-intermediate glass formers (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  17. Seismic fragility of ventilation stack of nuclear power plant

    International Nuclear Information System (INIS)

    Nefedov, S.S.; Yugai, T.Z.; Kalinkin, I.V.; Vizir, P.L.

    2003-01-01

    Fragility study of safety related elements is necessary step in seismic PSA of nuclear power plant (NPP). In present work fragility was analyzed after the example of the ventilation stack of NPP. Ventilation stack, considered in present work, is a separately erected construction with height of 100 m made of cast-in-place reinforced concrete. In accordance with IAEA terminology fragility of element is defined as conditional probability of its failure at given level of seismic loading. Failure of a ventilation stack was considered as development of the plastic hinge in some section of a shaft. Seismic ground acceleration a, which corresponds to failure, could be defined as limit seismic acceleration of ventilation stack [a]. Limit seismic acceleration [a] was considered as random value. Sources of its variation are connected with stochastic nature of factors determining it (properties of construction materials, soils etc.), and also with uncertainties of existing analytical techniques. Random value [a] was assumed to be distributed lognormally. Median m[a] and logarithmically standard deviation β of this distribution were defined by 'scaling method' developed by R.P. Kennedy et al. Using this values fragility curves were plotted for different levels of confidence probability. (author)

  18. Trabecular bone score as a skeletal fragility index in acromegaly patients.

    Science.gov (United States)

    Hong, A R; Kim, J H; Kim, S W; Kim, S Y; Shin, C S

    2016-03-01

    Lumbar spine trabecular bone score (TBS) was significantly decreased in active acromegaly patients. TBS may be useful to assess the skeletal fragility in acromegaly in which bone mineral density (BMD) is not sufficient to represent bone strength and explain the high incidence of fragility fractures in acromegaly patients. Although the data on BMD are controversial, patients with acromegaly have an increased risk of fragility fracture. We examined the lumbar spine TBS to explain the skeletal deterioration in acromegaly patients. We included 14 men and 19 women acromegaly patients who underwent dual-energy X-ray absorptiometry at the time of diagnosis from 2000 to 2014 at Seoul National University Hospital. Ninety-nine age-, sex- and body mass index-matched controls were recruited. Biochemical parameters, lumbar spine TBS, and BMD at all sites were measured. Gonadal status was evaluated at diagnosis. Lumbar spine TBS was lower in acromegaly patients than in controls in both genders (1.345 ± 0.121 vs. 1.427 ± 0.087, P = 0.005 in men; 1.356 ± 0.082 vs. 1.431 ± 0.071, P = 0.001 in women). In contrast, BMD at all sites did not differ between the two groups. Hypogonadal acromegaly patients (men, n = 9; women, n = 12) had lower TBS values compared with controls both in men and women (all P acromegaly patients, lumbar spine TBS was lower than in women controls only (P = 0.041). Skeletal microarchitecture was deteriorated in acromegaly patients as assessed by TBS, which seems to be a consequence of growth hormone excess as well as hypogonadism, especially in women.

  19. Time Dependent Assessment of Morphological Changes: Leukodepleted Packed Red Blood Cells Stored in SAGM

    Directory of Open Access Journals (Sweden)

    Ibrahim Mustafa

    2016-01-01

    Full Text Available Usually packed red blood cells (pRBCs require specific conditions in storage procedures to ensure the maximum shelf life of up to 42 days in 2–6°C. However, molecular and biochemical consequences can affect the stored blood cells; these changes are collectively labeled as storage lesions. In this study, the effect of prolonged storage was assessed through investigating morphological changes and evaluating oxidative stress. Samples from leukodepleted pRBC in SAGM stored at 4°C for 42 days were withdrawn aseptically on day 0, day 14, day 28, and day 42. Morphological changes were observed using scanning electron microscopy and correlated with osmotic fragility and hematocrit. Oxidative injury was studied through assessing MDA level as a marker for lipid peroxidation. Osmotic fragility test showed that extended storage time caused increase in the osmotic fragility. The hematocrit increased by 6.6% from day 0 to day 42. The last 2 weeks show alteration in the morphology with the appearance of echinocytes and spherocytes. Storage lesions and morphological alterations appeared to affect RBCs during the storage period. Further studies should be performed to develop strategies that will aid in the improvement of stored pRBC quality and efficacy.

  20. Development of an electro-osmotic heat pump

    NARCIS (Netherlands)

    Stoel, J.P. van der; Oostendorp, P.A.

    1999-01-01

    The majority of heat pumps and refrigerators is driven by a mechanical compressor. Although they usually function very well, the search for new and in some cases better heat pumping concepts continues. One of the topics in this field is the development of an electro-osmotic heat pump. As each

  1. Effect of temperature and cultivar on polyphenol retention and mass transfer during osmotic dehydration of apples.

    Science.gov (United States)

    Devic, Emilie; Guyot, Sylvain; Daudin, Jean-Dominique; Bonazzi, Catherine

    2010-01-13

    Several cultivars of apples (Malus domestica) were chosen for their variable concentrations and compositions in phenolic compounds. Cubed samples (1 cm3) were subjected to osmotic dehydration, and the effect of temperature was studied at 45 and 60 degrees C. Water loss, sucrose impregnation, and the evolution of some natural components of the product were followed to quantify mass transfer. Ascorbic acid and polyphenols were quantified by HPLC for several osmotic dehydration times and regardless of the quantity of impregnated sugar. Changes in antioxidant components differed as a function of the nature of molecules. Their concentrations decreased in line with temperature, and few differences were observed between cultivars. Processing at a lower temperature (45 degrees C) caused a total loss in ascorbic acid but allowed the retention of between 74 and 85% of initial polyphenols, depending on the cultivar. Cultivars containing highly polymerized procyanidins (such as Guillevic) experienced less loss. Hydroxycinnamic acids and monomeric catechins displayed the most marked changes. Leaching with water into the soaking solution was the principal mechanism retained to explain these losses.

  2. Handbook of nuclear power plant seismic fragilities, Seismic Safety Margins Research Program

    International Nuclear Information System (INIS)

    Cover, L.E.; Bohn, M.P.; Campbell, R.D.; Wesley, D.A.

    1983-12-01

    The Seismic Safety Margins Research Program (SSMRP) has a gola to develop a complete fully coupled analysis procedure (including methods and computer codes) for estimating the risk of an earthquake-induced radioactive release from a commercial nuclear power plant. As part of this program, calculations of the seismic risk from a typical commercial nuclear reactor were made. These calculations required a knowledge of the probability of failure (fragility) of safety-related components in the reactor system which actively participate in the hypothesized accident scenarios. This report describes the development of the required fragility relations and the data sources and data reduction techniques upon which they are based. Both building and component fragilities are covered. The building fragilities are for the Zion Unit 1 reactor which was the specific plant used for development of methodology in the program. Some of the component fragilities are site-specific also, but most would be usable for other sites as well

  3. Quercitol and osmotic adaptation of field-grown Eucalyptus under seasonal drought stress.

    Science.gov (United States)

    Arndt, Stefan K; Livesley, Stephen J; Merchant, Andrew; Bleby, Timothy M; Grierson, Pauline F

    2008-07-01

    This study investigated the role of quercitol in osmotic adjustment in field-grown Eucalyptus astringens Maiden subject to seasonal drought stress over the course of 1 year. The trees grew in a native woodland and a farm plantation in the semi-arid wheatbelt region of south Western Australia. Plantation trees allocated relatively more biomass to leaves than woodland trees, but they suffered greater drought stress over summer, as indicated by lower water potentials, CO(2)assimilation rates and stomatal conductances. In contrast, woodland trees had relatively fewer leaves and suffered less drought stress. Plantation trees under drought stress engaged in osmotic adjustment, but woodland trees did not. Quercitol made a significant contribution to osmotic adjustment in drought-stressed trees (25% of total solutes), and substantially more quercitol was measured in the leaves of plantation trees (5% dry matter) than in the leaves of woodland trees (2% dry matter). We found no evidence that quercitol was used as a carbon storage compound while starch reserves were depleted under drought stress. Differences in stomatal conductance, biomass allocation and quercitol production clearly indicate that E. astringens is both morphologically and physiologically 'plastic' in response to growth environment, and that osmotic adjustment is only one part of a complex strategy employed by this species to tolerate drought.

  4. Effect of process variables on the osmotic dehydration of star-fruit slices

    Directory of Open Access Journals (Sweden)

    Camila Dalben Madeira Campos

    2012-06-01

    Full Text Available The objective of this work was to study the effect of blanching and the influence of temperature, solution concentration, and the initial fruit:solution ratio on the osmotic dehydration of star-fruit slices. For blanching, different concentrations of citric and ascorbic acids were studied. The samples immersed in 0.75% citric acid presented little variation in color in relation to the fresh star-fruit. Osmotic dehydration was carried out in an incubator with orbital shaking, controlled temperature, and constant shaking at 120 rpm. The influence of process variables was studied in trials defined by a complete 23 central composite design. In general, water loss and solids gain were positively influenced by temperature and by solution concentration. Nevertheless, lower temperatures reduced water loss throughout the osmotic dehydration process. An increase in the amount of dehydrating solution (initial fruit:solution ratio slightly influenced the evaluated responses. The process carried out at 50 ºC with a solution concentration of 50% resulted in a product with lower solids gain and greater water loss. Under these conditions, blanching minimized the effect of the osmotic treatment on star-fruit browning, and therefore the blanched fruits showed little variation in color in relation to the fresh fruit.

  5. Cities could hold the key to understanding fragility | CRDI - Centre ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Cities are engines of economic growth and the primary sites of basic service delivery. Yet weak governance, along with inequalities related to income, social class, religion, and gender, may lead to a breakdown of systems and structures, and eventually to "fragile cities." Although the fragile cities concept is relatively new, ...

  6. RTEL1 Inhibits Trinucleotide Repeat Expansions and Fragility

    Directory of Open Access Journals (Sweden)

    Aisling Frizzell

    2014-03-01

    Full Text Available Human RTEL1 is an essential, multifunctional helicase that maintains telomeres, regulates homologous recombination, and helps prevent bone marrow failure. Here, we show that RTEL1 also blocks trinucleotide repeat expansions, the causal mutation for 17 neurological diseases. Increased expansion frequencies of (CTG⋅CAG repeats occurred in human cells following knockdown of RTEL1, but not the alternative helicase Fbh1, and purified RTEL1 efficiently unwound triplet repeat hairpins in vitro. The expansion-blocking activity of RTEL1 also required Rad18 and HLTF, homologs of yeast Rad18 and Rad5. These findings are reminiscent of budding yeast Srs2, which inhibits expansions, unwinds hairpins, and prevents triplet-repeat-induced chromosome fragility. Accordingly, we found expansions and fragility were suppressed in yeast srs2 mutants expressing RTEL1, but not Fbh1. We propose that RTEL1 serves as a human analog of Srs2 to inhibit (CTG⋅CAG repeat expansions and fragility, likely by unwinding problematic hairpins.

  7. Fragile X syndrome: A review of clinical management

    Science.gov (United States)

    Lozano, Reymundo; Azarang, Atoosa; Wilaisakditipakorn, Tanaporn; Hagerman, Randi J

    2016-01-01

    Summary The fragile X mental retardation 1 gene, which codes for the fragile X mental retardation 1 protein, usually has 5 to 40 CGG repeats in the 5′ untranslated promoter. The full mutation is the almost always the cause of fragile X syndrome (FXS). The prevalence of FXS is about 1 in 4,000 to 1 in 7,000 in the general population although the prevalence varies in different regions of the world. FXS is the most common inherited cause of intellectual disability and autism. The understanding of the neurobiology of FXS has led to many targeted treatments, but none have cured this disorder. The treatment of the medical problems and associated behaviors remain the most useful intervention for children with FXS. In this review, we focus on the non-pharmacological and pharmacological management of medical and behavioral problems associated with FXS as well as current recommendations for follow-up and surveillance. PMID:27672537

  8. Pathological Plasticity in Fragile X Syndrome

    Directory of Open Access Journals (Sweden)

    Brandon S. Martin

    2012-01-01

    Full Text Available Deficits in neuronal plasticity are common hallmarks of many neurodevelopmental disorders. In the case of fragile-X syndrome (FXS, disruption in the function of a single gene, FMR1, results in a variety of neurological consequences directly related to problems with the development, maintenance, and capacity of plastic neuronal networks. In this paper, we discuss current research illustrating the mechanisms underlying plasticity deficits in FXS. These processes include synaptic, cell intrinsic, and homeostatic mechanisms both dependent on and independent of abnormal metabotropic glutamate receptor transmission. We place particular emphasis on how identified deficits may play a role in developmental critical periods to produce neuronal networks with permanently decreased capacity to dynamically respond to changes in activity central to learning, memory, and cognition in patients with FXS. Characterizing early developmental deficits in plasticity is fundamental to develop therapies that not only treat symptoms but also minimize the developmental pathology of the disease.

  9. Fluorescent in-situ hybridization of cattle and sheep chromosomes with cloned human fragile-X DNA

    DEFF Research Database (Denmark)

    Ali, Ahmd; Thomsen, Preben Dybdahl; Babar, M.E.

    2009-01-01

    An extensive study on spontaneous and 5-Fluorodeoxyuridine induced fragile sites identified Xq31 in cattle (Bos taurus) and (Xq24, Xq26) in sheep (Ovis aries) in addition to several autosomal fragile sites (under publication). A ZOO-FISH study using three cloned human fragile-X probes with CCG....../CGG(n) trinucleotide repeat sequence was carried out to determine homology between human and bovine fragile-X. The hybridisation results showed only a weak signal on a human chromosome that was not an X with all three fragile site probes. No signals were detected in sheep chromosomes. The signal of all three human...... fragile-X probes on cattle chromosomes was however, medium-prominent sub-centromeric signal on two homologues. BrdU administration in 12 h before harvesting identified these homologues to be chromosome number 5. In addition retrospective slides of cattle and sheep chromosomes used for fragile site studies...

  10. Drying of carrots in slices with osmotic dehydration

    African Journals Online (AJOL)

    SAM

    2014-07-23

    Jul 23, 2014 ... extend the shelf-life by a few weeks, one year or more. The methods .... drated carrots, this work studied the drying of carrot with pre-osmotic ... e) Weight Loss - obtained directly using balance semi-analytical model BEL ...

  11. Modeling Fragile X Syndrome in Drosophila

    Science.gov (United States)

    Drozd, Małgorzata; Bardoni, Barbara; Capovilla, Maria

    2018-01-01

    Intellectual disability (ID) and autism are hallmarks of Fragile X Syndrome (FXS), a hereditary neurodevelopmental disorder. The gene responsible for FXS is Fragile X Mental Retardation gene 1 (FMR1) encoding the Fragile X Mental Retardation Protein (FMRP), an RNA-binding protein involved in RNA metabolism and modulating the expression level of many targets. Most cases of FXS are caused by silencing of FMR1 due to CGG expansions in the 5′-UTR of the gene. Humans also carry the FXR1 and FXR2 paralogs of FMR1 while flies have only one FMR1 gene, here called dFMR1, sharing the same level of sequence homology with all three human genes, but functionally most similar to FMR1. This enables a much easier approach for FMR1 genetic studies. Drosophila has been widely used to investigate FMR1 functions at genetic, cellular, and molecular levels since dFMR1 mutants have many phenotypes in common with the wide spectrum of FMR1 functions that underlay the disease. In this review, we present very recent Drosophila studies investigating FMRP functions at genetic, cellular, molecular, and electrophysiological levels in addition to research on pharmacological treatments in the fly model. These studies have the potential to aid the discovery of pharmacological therapies for FXS. PMID:29713264

  12. Two tandem RNase III cleavage sites determine betT mRNA stability in response to osmotic stress in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Minji Sim

    Full Text Available While identifying genes regulated by ribonuclease III (RNase III in Escherichia coli, we observed that steady-state levels of betT mRNA, which encodes a transporter mediating the influx of choline, are dependent on cellular concentrations of RNase III. In the present study, we also observed that steady-state levels of betT mRNA are dependent on RNase III activity upon exposure to osmotic stress, indicating the presence of cis-acting elements controlled by RNase III in betT mRNA. Primer extension analyses of betT mRNA revealed two tandem RNase III cleavage sites in its stem-loop region, which were biochemically confirmed via in vitro cleavage assays. Analyses of cleavage sites suggested the stochastic selection of cleavage sites by RNase III, and mutational analyses indicated that RNase III cleavage at either site individually is insufficient for efficient betT mRNA degradation. In addition, both the half-life and abundance of betT mRNA were significantly increased in association with decreased RNase III activity under hyper-osmotic stress conditions. Our findings demonstrate that betT mRNA stability is controlled by RNase III at the post-transcriptional level under conditions of osmotic stress.

  13. Thermalization as an Invisibility Cloak for Fragile Quantum Superpositions

    OpenAIRE

    Hahn, Walter; Fine, Boris V.

    2017-01-01

    We propose a method for protecting fragile quantum superpositions in many-particle systems from dephasing by external classical noise. We call superpositions "fragile" if dephasing occurs particularly fast, because the noise couples very differently to the superposed states. The method consists of letting a quantum superposition evolve under the internal thermalization dynamics of the system, followed by a time reversal manipulation known as Loschmidt echo. The thermalization dynamics makes t...

  14. Osmotic coefficients and apparent molar volumes of 1-hexyl-3-methylimidazolium trifluoromethanesulfonate ionic liquid in alcohols

    International Nuclear Information System (INIS)

    González, Emilio J.; Calvar, Noelia; Macedo, Eugénia A.

    2014-01-01

    Highlights: • Physical and osmotic properties of [HMim][TfO] in alcohols are reported. • Apparent molar properties and osmotic coefficients were obtained. • Apparent molar volumes were fitted using a Redlich–Meyer type equation. • The osmotic coefficients were modeled with the Extended Pitzer and the MNRTL models. -- Abstract: In this work, density for the binary mixtures of 1-hexyl-3-methylimidazolium trifluoromethanesulfonate in alcohols (1-propanol, or 2-propanol, or 1-butanol, or 2-butanol, or 1-pentanol) was measured at T = 323.15 K and atmospheric pressure. From this property, the corresponding apparent molar volumes were calculated and fitted to a Redlich–Meyer type equation. For these mixtures, the osmotic and activity coefficients, and vapor pressures of these binary systems were also determined at the same temperature using the vapor pressure osmometry technique. The experimental osmotic coefficients were modeled by the Extended Pitzer model of Archer. The parameters obtained in this correlation were used to calculate the mean molal activity coefficients and the excess Gibbs free energy for the studied mixtures

  15. Babies at Double Jeopardy: Medically Fragile Infants and Child Neglect

    Science.gov (United States)

    Fullar, Suzanne A.

    2008-01-01

    Medically fragile infants, those born prematurely or with other complex medical or genetic problems, are at risk of long-term health and developmental problems. When a medically fragile infant comes home to a family with significant social problems such as domestic violence, mental illness, or substance abuse, the infant is at double jeopardy--at…

  16. Self-Injurious Behavior and Fragile X Syndrome: Findings from the National Fragile X Survey

    Science.gov (United States)

    Symons, Frank J.; Byiers, Breanne J.; Raspa, Melissa; Bishop, Ellen; Bailey, Donald B., Jr.

    2010-01-01

    We used National Fragile X Survey data in order to examine reported self-injurious behavior (SIB) to (a) generate lifetime and point prevalence estimates, (b) document detailed features of SIB (frequency, types, location, severity) in relation to gender, and (c) compare comorbid conditions between matched pairs (SIB vs. no SIB). Results indicate…

  17. Osmotic concentration in three races of honey bee, Apis mellifera L. under environmental conditions of arid zone.

    Science.gov (United States)

    Ali, Hussain; Alqarni, Abdulaziz S; Owayss, Ayman A; Hassan, Awad M; Smith, Brian H

    2017-07-01

    Hemolymph osmolarity has great effect on honey bee health, especially in arid and semi-arid zones. It regulates water and nutrients in stressed tissues. Osmotic concentration in three races ( Apis mellifera ligustica , A. m. carnica and A. m. jemenitica ) of Apis mellifera was tested in central Saudi Arabia during spring and summer seasons in 2015. Newly emerged bee workers were first marked and later their hemolymph was extracted after intervals of 1, 5, 10, 15, 20 and 25 days. A significant positive correlation between age and osmolarity was found in all three races during spring and summer seasons. The lowest combined osmotic concentration for all three races was found after 1 day interval, while the highest osmotic concentration was recorded after 25 days. Among all races, A. m. ligustica showed significantly high osmotic concentration after 25 days in spring and summer seasons as compared to the other two races. Only A. m. jemenitica showed similar osmotic concentration after 10 and 15 days in both spring and summer seasons compared to other two races. Mean osmotic concentration of all three races was significantly different after 20 and 25 days in spring and summer seasons. Overall mean recorded during summer was significantly higher than the mean of spring season. Combined osmotic concentration in young drones of all races was significantly lower than that of old drones during spring and summer seasons.

  18. Positron Emission Tomography (PET Quantification of GABAA Receptors in the Brain of Fragile X Patients.

    Directory of Open Access Journals (Sweden)

    Charlotte D'Hulst

    Full Text Available Over the last several years, evidence has accumulated that the GABAA receptor is compromised in animal models for fragile X syndrome (FXS, a common hereditary form of intellectual disability. In mouse and fly models, agonists of the GABAA receptor were able to rescue specific consequences of the fragile X mutation. Here, we imaged and quantified GABAA receptors in vivo in brain of fragile X patients using Positron Emission Topography (PET and [11C]flumazenil, a known high-affinity and specific ligand for the benzodiazepine site of GABAA receptors. We measured regional GABAA receptor availability in 10 fragile X patients and 10 control subjects. We found a significant reduction of on average 10% in GABAA receptor binding potential throughout the brain in fragile X patients. In the thalamus, the brain region showing the largest difference, the GABAA receptor availability was even reduced with 17%. This is one of the first reports of a PET study of human fragile X brain and directly demonstrates that the GABAA receptor availability is reduced in fragile X patients. The study reinforces previous hypotheses that the GABAA receptor is a potential target for rational pharmacological treatment of fragile X syndrome.

  19. Analytical Expressions for Thermo-Osmotic Permeability of Clays

    Science.gov (United States)

    Gonçalvès, J.; Ji Yu, C.; Matray, J.-M.; Tremosa, J.

    2018-01-01

    In this study, a new formulation for the thermo-osmotic permeability of natural pore solutions containing monovalent and divalent cations is proposed. The mathematical formulation proposed here is based on the theoretical framework supporting thermo-osmosis which relies on water structure alteration in the pore space of surface-charged materials caused by solid-fluid electrochemical interactions. The ionic content balancing the surface charge of clay minerals causes a disruption in the hydrogen bond network when more structured water is present at the clay surface. Analytical expressions based on our heuristic model are proposed and compared to the available data for NaCl solutions. It is shown that the introduction of divalent cations reduces the thermo-osmotic permeability by one third compared to the monovalent case. The analytical expressions provided here can be used to advantage for safety calculations in deep underground nuclear waste repositories.

  20. A new insight into membrane fouling mechanism in submerged membrane bioreactor: osmotic pressure during cake layer filtration.

    Science.gov (United States)

    Zhang, Meijia; Peng, Wei; Chen, Jianrong; He, Yiming; Ding, Linxian; Wang, Aijun; Lin, Hongjun; Hong, Huachang; Zhang, Ye; Yu, Haiying

    2013-05-15

    Big gap between experimental filtration resistance of cake layer formed on membrane surface and the hydraulic resistance calculated through the Carman-Kozeny equation, suggested the existence of a new membrane fouling mechanism: osmotic pressure during cake layer filtration in SMBR system. An osmotic pressure model based on chemical potential difference was then proposed. Simulation of the model showed that osmotic pressure accounted for the major fraction of total operation pressure, and pH, applied pressure and ionic strength were the key determining factors for osmosis effect. It was found that, variations of osmotic pressure with pH, applied pressure and added ionic strength were well coincident with perditions of model's simulation, providing the first direct evidences of the real occurrence of osmosis mechanism and the feasibility of the proposed model. These findings illustrate the essential role of osmotic pressure in filtration resistance, and improve fundamental understanding on membrane fouling in SMBR systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Fragility curves for bridges under differential support motions

    DEFF Research Database (Denmark)

    Konakli, Katerina

    2012-01-01

    This paper employs the notion of fragility to investigate the seismic vulnerability of bridges subjected to spatially varying support motions. Fragility curves are developed for four highway bridges in California with vastly different structural characteristics. The input in this analysis consists...... of simulated ground motion arrays with temporal and spectral nonstationarities, and consistent with prescribed spatial variation patterns. Structural damage is quantified through displacement ductility demands obtained from nonlinear time-history analysis. The potential use of the ‘equal displacement’ rule...... to approximately evaluate displacement demands from analysis of the equivalent linear systems is examined....

  2. A physiological evaluation of the enhanced osmotic stress tolerance ...

    African Journals Online (AJOL)

    ELO

    2012-01-05

    Jan 5, 2012 ... SR3 and Jinan 177 were hydroponically subjected to osmotic stress, the accumulation of proline .... hydroponically in half strength Hoagland's solution for three weeks ..... ascrobate specific peroxidase in spinach chloroplasts.

  3. Methods to increase the rate of mass transfer during osmotic dehydration of foods.

    Science.gov (United States)

    Chwastek, Anna

    2014-01-01

    Traditional methods of food preservation such as freezing, freeze drying (lyophilization), vacuum drying, convection drying are often supplemented by new technologies that enable obtaining of high quality products. Osmotic dehydration is more and more often used during processing of fruits and vegetables. This method allows maintaining good organoleptic and functional properties in the finished product. Obtaining the desired degree of dehydration or saturation of the material with an osmoactive substance often requires  elongation of time or use of high temperatures. In recent years much attention was devoted to techniques aimed at increasing the mass transfer between the dehydrated material and the hypertonic solution. The work reviews the literature focused on methods of streamlining the process of osmotic dehydration which include the use of: ultrasound, high hydrostatic pressure, vacuum osmotic dehydration and pulsed electric field.

  4. Fragile X premutation carriers: A systematic review of neuroimaging findings.

    Science.gov (United States)

    Brown, Stephanie S G; Stanfield, Andrew C

    2015-05-15

    Expansion of the CGG repeat region of the FMR1 gene from less than 45 repeats to between 55 and 200 repeats is known as the fragile X premutation. Carriers of the fragile X premutation may develop a neurodegenerative disease called fragile X-associated tremor/ataxia syndrome (FXTAS). Recent evidence suggests that premutation carriers experience other psychiatric difficulties throughout their lifespan. Medline, EMBASE and PsychINFO were searched for all appropriate English language studies published between January 1990 and December 2013. 419 potentially relevant articles were identified and screened. 19 articles were included in the analysis. We discuss key structural magnetic resonance imaging (MRI) findings such as the MCP sign and white matter atrophy. Additionally, we discuss how functional MRI results have progressed our knowledge of how FXTAS may manifest, including reduced brain activation during social and memory tasks in multiple regions. This systematic review may have been limited by the search for articles on just 3 scientific databases. Differing techniques and methods of analyses between research groups and primary research articles may have caused differences in results between studies. Current MRI studies into the fragile X premutation have been important in the diagnosis of FXTAS and identifying potential pathophysiological mechanisms. Associations with blood based measures have also demonstrated that neurodevelopmental and neurodegenerative aspects of the fragile X premutation could be functionally and pathologically separate. Larger longitudinal studies will be required to investigate these conclusions. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Fragile Cities: a Critical Perspective on the Repertoire for New Urban Humanitarian Interventions

    Directory of Open Access Journals (Sweden)

    Manoela Miklos

    Full Text Available Abstract At the end of the 1990s, researchers involved in the debate on the new wars introduced discussion about the urban dimension of contemporary conflicts into the International Relations discipline. The innovative debate about urban fragility is one of the many lines of inquiry that emerge within the framework of the relationship between cities and contemporary conflicts. This paper seeks to demonstrate that the concept of ‘fragile city’ offers a new and relevant analytical framework for understanding contemporary urban violence and inequality. Moreover, this same concept could also be instrumental in making fragile cities the new locus of international humanitarianism. The notion of fragile city emerges to describe new emergency situations more closely linked to urban contexts than to national dynamics, as previously described in the literature on fragile states. The concept of fragile city is a groundbreaking tool for understanding the human consequences of inequality in urban settings, but might also be used as a rhetorical vehicle for the reproduction of old dynamics and the inauguration of new intervention practices in urban areas that were previously inaccessible to humanitarian action, especially cities in Latin America.

  6. Component Fragility Research Program: Phase 1, Demonstration tests: Volume 1, Summary report

    International Nuclear Information System (INIS)

    Holman, G.S.; Chou, C.K.; Shipway, G.D.; Glozman, V.

    1987-08-01

    This report describes tests performed in Phase I of the NRC Component Fragility Research Program. The purpose of these tests was to demonstrate procedures for characterizing the seismic fragility of a selected component, investigating how various parameters affect fragility, and finally using test data to develop practical fragility descriptions suitable for application in probabilistic risk assessments. A three-column motor control center housing motor controllers of various types and sizes as well as relays of different types and manufacturers was subjected to seismic input motions up to 2.5g zero period acceleration. To investigate the effect of base flexibility on the structural behavior of the MCC and on the functional behavior of the electrical devices, multiple tests were performed on each of four mounting configurations: four bolts per column with top bracking, four bolts per column with no top brace, four bolts per column with internal diagonal bracking, and two bolts per column with no top or internal bracking. Device fragility was characterized by contact chatter correlated to local in-cabinet response at the device location. Seismic capacities were developed for each device on the basis of local input motion required to cause chatter; these results were then applied to develop probabilistic fragility curves for each type of device, including estimates of the ''high-confidence low probability of failure'' capacity of each

  7. Self-consistent unstirred layers in osmotically driven flows

    DEFF Research Database (Denmark)

    Jensen, Kåre Hartvig; Bohr, Tomas; Bruus, Henrik

    2010-01-01

    It has long been recognized that the osmotic transport characteristics of membranes may be strongly influenced by the presence of unstirred concentration boundary layers adjacent to the membrane. Previous experimental as well as theoretical works have mainly focused on the case where the solutions...

  8. Fragile X mental retardation protein participates in non-coding RNA pathways.

    Science.gov (United States)

    Li, En-Hui; Zhao, Xin; Zhang, Ce; Liu, Wei

    2018-02-20

    Fragile X syndrome is one of the most common forms of inherited intellectual disability. It is caused by mutations of the Fragile X mental retardation 1(FMR1) gene, resulting in either the loss or abnormal expression of the Fragile X mental retardation protein (FMRP). Recent research showed that FMRP participates in non-coding RNA pathways and plays various important roles in physiology, thereby extending our knowledge of the pathogenesis of the Fragile X syndrome. Initial studies showed that the Drosophila FMRP participates in siRNA and miRNA pathways by interacting with Dicer, Ago1 and Ago2, involved in neural activity and the fate determination of the germline stem cells. Subsequent studies showed that the Drosophila FMRP participates in piRNA pathway by interacting with Aub, Ago1 and Piwi in the maintenance of normal chromatin structures and genomic stability. More recent studies showed that FMRP is associated with lncRNA pathway, suggesting a potential role for the involvement in the clinical manifestations. In this review, we summarize the novel findings and explore the relationship between FMRP and non-coding RNA pathways, particularly the piRNA pathway, thereby providing critical insights on the molecular pathogenesis of Fragile X syndrome, and potential translational applications in clinical management of the disease.

  9. Osmotic stress, endogenous abscisic acid and the control of leaf morphology in Hippuris vulgaris L

    Science.gov (United States)

    Goliber, T. E.; Feldman, L. J.

    1989-01-01

    Previous reports indicate that heterophyllous aquatic plants can be induced to form aerial-type leaves on submerged shoots when they are grown in exogenous abscisic acid (ABA). This study reports on the relationship between osmotic stress (e.g. the situation encountered by a shoot tip when it grows above the water surface), endogenous ABA (as measured by gas chromatography-electron capture detector) and leaf morphology in the heterophyllous aquatic plant, Hippuris vulgaris. Free ABA could not be detected in submerged shoots of H. vulgaris but in aerial shoots ABA occurred at ca. 40 ng (g fr wt)-1. When submerged shoots were osmotically stressed ABA appeared at levels of 26 to 40 ng (g fr wt)-1. These and other data support two main conclusions: (1) Osmotically stressing a submerged shoot causes the appearance of detectable levels of ABA. (2) The rise of ABA in osmotically stressed submerged shoots in turn induces a change in leaf morphology from the submerged to the aerial form. This corroborates the hypothesis that, in the natural environment, ABA levels rise in response to the osmotic stress encountered when a submerged shoot grows up through the water/air interface and that the increased ABA leads to the production of aerial-type leaves.

  10. Modelling reveals endogenous osmotic adaptation of storage tissue water potential as an important driver determining different stem diameter variation patterns in the mangrove species Avicennia marina and Rhizophora stylosa.

    Science.gov (United States)

    Vandegehuchte, Maurits W; Guyot, Adrien; Hubeau, Michiel; De Swaef, Tom; Lockington, David A; Steppe, Kathy

    2014-09-01

    Stem diameter variations are mainly determined by the radial water transport between xylem and storage tissues. This radial transport results from the water potential difference between these tissues, which is influenced by both hydraulic and carbon related processes. Measurements have shown that when subjected to the same environmental conditions, the co-occurring mangrove species Avicennia marina and Rhizophora stylosa unexpectedly show a totally different pattern in daily stem diameter variation. Using in situ measurements of stem diameter variation, stem water potential and sap flow, a mechanistic flow and storage model based on the cohesion-tension theory was applied to assess the differences in osmotic storage water potential between Avicennia marina and Rhizophora stylosa. Both species, subjected to the same environmental conditions, showed a resembling daily pattern in simulated osmotic storage water potential. However, the osmotic storage water potential of R. stylosa started to decrease slightly after that of A. marina in the morning and increased again slightly later in the evening. This small shift in osmotic storage water potential likely underlaid the marked differences in daily stem diameter variation pattern between the two species. The results show that in addition to environmental dynamics, endogenous changes in the osmotic storage water potential must be taken into account in order to accurately predict stem diameter variations, and hence growth.

  11. Hybrid Pressure Retarded Osmosis−Membrane Distillation (PRO−MD) Process for Osmotic Power and Clean Water Generation

    KAUST Repository

    Han, Gang; Zuo, Jian; Wan, Chunfeng; Chung, Neal Tai-Shung

    2015-01-01

    unique advantages of high water recovery rate, huge osmotic power generation, well controlled membrane fouling, and minimal environmental impacts. Experimental results show that the PRO−MD hybrid process is promising that not only can harvest osmotic

  12. Modulation of δ-Aminolevulinic Acid Dehydratase Activity by the Sorbitol-Induced Osmotic Stress in Maize Leaf Segments.

    Science.gov (United States)

    Jain, M; Tiwary, S; Gadre, R

    2018-01-01

    Osmotic stress induced with 1 M sorbitol inhibited δ-aminolevulinic acid dehydratase (ALAD) and aminolevulinic acid (ALA) synthesizing activities in etiolated maize leaf segments during greening; the ALAD activity was inhibited to a greater extent than the ALA synthesis. When the leaves were exposed to light, the ALAD activity increased for the first 8 h, followed by a decrease observed at 16 and 24 h in both sorbitol-treated and untreated leaf tissues. The maximum inhibition of the enzyme activity was observed in the leaf segments incubated with sorbitol for 4 to 8 h. Glutamate increased the ALAD activity in the in vitro enzymatic preparations obtained from the sorbitol-treated leaf segments; sorbitol inhibited the ALAD activity in the preparations from both sorbitol-treated and untreated leaves. It was suggested that sorbitol-induced osmotic stress inhibits the enzyme activity by affecting the ALAD induction during greening and regulating the ALAD steady-state level of ALAD in leaf cells. The protective effect of glutamate on ALAD in the preparations from the sorbitol-treated leaves might be due to its stimulatory effect on the enzyme.

  13. OSMOTIC FRAGILITY AND Na + -K + + ATPase ACTIVITY OF ...

    African Journals Online (AJOL)

    + -K+ ATPase activity of the erythrocytes of HIV/AIDS patients. Whole blood was taken from subjects at the Human Virology Laboratory of the Nigerian Institute of Medical Research. Subjects were judged suitable for the various investigations by ...

  14. RTEL1 inhibits trinucleotide repeat expansions and fragility.

    Science.gov (United States)

    Frizzell, Aisling; Nguyen, Jennifer H G; Petalcorin, Mark I R; Turner, Katherine D; Boulton, Simon J; Freudenreich, Catherine H; Lahue, Robert S

    2014-03-13

    Human RTEL1 is an essential, multifunctional helicase that maintains telomeres, regulates homologous recombination, and helps prevent bone marrow failure. Here, we show that RTEL1 also blocks trinucleotide repeat expansions, the causal mutation for 17 neurological diseases. Increased expansion frequencies of (CTG⋅CAG) repeats occurred in human cells following knockdown of RTEL1, but not the alternative helicase Fbh1, and purified RTEL1 efficiently unwound triplet repeat hairpins in vitro. The expansion-blocking activity of RTEL1 also required Rad18 and HLTF, homologs of yeast Rad18 and Rad5. These findings are reminiscent of budding yeast Srs2, which inhibits expansions, unwinds hairpins, and prevents triplet-repeat-induced chromosome fragility. Accordingly, we found expansions and fragility were suppressed in yeast srs2 mutants expressing RTEL1, but not Fbh1. We propose that RTEL1 serves as a human analog of Srs2 to inhibit (CTG⋅CAG) repeat expansions and fragility, likely by unwinding problematic hairpins. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Selective Spatial Processing Deficits in an At-Risk Subgroup of the Fragile X Premutation

    Science.gov (United States)

    Hocking, Darren R.; Kogan, Cary S.; Cornish, Kim M.

    2012-01-01

    Until a decade ago, it was assumed that males with the fragile X premutation were unaffected by any cognitive phenotype. Here we examined the extent to which CGG repeat toxicity extends to visuospatial functioning in male fragile X premutation carriers who are asymptomatic for a late-onset neurodegenerative disorder, fragile X-associated…

  16. Effect of Osmotic Pressure on the Stability of Whole Inactivated Influenza Vaccine for Coating on Microneedles.

    Directory of Open Access Journals (Sweden)

    Hyo-Jick Choi

    Full Text Available Enveloped virus vaccines can be damaged by high osmotic strength solutions, such as those used to protect the vaccine antigen during drying, which contain high concentrations of sugars. We therefore studied shrinkage and activity loss of whole inactivated influenza virus in hyperosmotic solutions and used those findings to improve vaccine coating of microneedle patches for influenza vaccination. Using stopped-flow light scattering analysis, we found that the virus underwent an initial shrinkage on the order of 10% by volume within 5 s upon exposure to a hyperosmotic stress difference of 217 milliosmolarity. During this shrinkage, the virus envelope had very low osmotic water permeability (1 - 6×10-4 cm s-1 and high Arrhenius activation energy (Ea = 15.0 kcal mol-1, indicating that the water molecules diffused through the viral lipid membranes. After a quasi-stable state of approximately 20 s to 2 min, depending on the species and hypertonic osmotic strength difference of disaccharides, there was a second phase of viral shrinkage. At the highest osmotic strengths, this led to an undulating light scattering profile that appeared to be related to perturbation of the viral envelope resulting in loss of virus activity, as determined by in vitro hemagglutination measurements and in vivo immunogenicity studies in mice. Addition of carboxymethyl cellulose effectively prevented vaccine activity loss in vitro and in vivo, believed to be due to increasing the viscosity of concentrated sugar solution and thereby reducing osmotic stress during coating of microneedles. These results suggest that hyperosmotic solutions can cause biphasic shrinkage of whole inactivated influenza virus which can damage vaccine activity at high osmotic strength and that addition of a viscosity enhancer to the vaccine coating solution can prevent osmotically driven damage and thereby enable preparation of stable microneedle coating formulations for vaccination.

  17. Astrocyte-secreted thrombospondin-1 modulates synapse and spine defects in the fragile X mouse model.

    Science.gov (United States)

    Cheng, Connie; Lau, Sally K M; Doering, Laurie C

    2016-08-02

    Astrocytes are key participants in various aspects of brain development and function, many of which are executed via secreted proteins. Defects in astrocyte signaling are implicated in neurodevelopmental disorders characterized by abnormal neural circuitry such as Fragile X syndrome (FXS). In animal models of FXS, the loss in expression of the Fragile X mental retardation 1 protein (FMRP) from astrocytes is associated with delayed dendrite maturation and improper synapse formation; however, the effect of astrocyte-derived factors on the development of neurons is not known. Thrombospondin-1 (TSP-1) is an important astrocyte-secreted protein that is involved in the regulation of spine development and synaptogenesis. In this study, we found that cultured astrocytes isolated from an Fmr1 knockout (Fmr1 KO) mouse model of FXS displayed a significant decrease in TSP-1 protein expression compared to the wildtype (WT) astrocytes. Correspondingly, Fmr1 KO hippocampal neurons exhibited morphological deficits in dendritic spines and alterations in excitatory synapse formation following long-term culture. All spine and synaptic abnormalities were prevented in the presence of either astrocyte-conditioned media or a feeder layer derived from FMRP-expressing astrocytes, or following the application of exogenous TSP-1. Importantly, this work demonstrates the integral role of astrocyte-secreted signals in the establishment of neuronal communication and identifies soluble TSP-1 as a potential therapeutic target for Fragile X syndrome.

  18. Takagi-Sugeno Fuzzy Systems Non-fragile H-infinity Filtering

    CERN Document Server

    Chang, Xiao-Heng

    2012-01-01

    "Takagi-Sugeno Fuzzy Systems Non-fragile H-infinity Filtering" investigates the problem of non-fragile H-infinity filter design for T-S fuzzy systems. The nonlinear plant is represented by a T-S fuzzy model. Given a T-S fuzzy system, the objective of this book is to design an H-infinity filter with the gain variations such that the filtering error system guarantees a prescribed H-infinity performance level. Furthermore, it demonstrates that the solution of non-fragile H-infinity filter design problem can be obtained by solving a set of linear matrix inequalities (LMIs). The intended audiences are graduate students and researchers both from the fields of engineering and mathematics. Dr. Xiao-Heng Chang is an Associate Professor at the College of Engineering, Bohai University, Jinzhou, Liaoning, China. He is also a Postdoctoral Researcher at the College of Information Science and Engineering, Northeastern University, Shenyang, China.

  19. Novel Regulation of Aquaporins during Osmotic Stress1

    Science.gov (United States)

    Vera-Estrella, Rosario; Barkla, Bronwyn J.; Bohnert, Hans J.; Pantoja, Omar

    2004-01-01

    Aquaporin protein regulation and redistribution in response to osmotic stress was investigated. Ice plant (Mesembryanthemum crystallinum) McTIP1;2 (McMIPF) mediated water flux when expressed in Xenopus leavis oocytes. Mannitol-induced water imbalance resulted in increased protein amounts in tonoplast fractions and a shift in protein distribution to other membrane fractions, suggesting aquaporin relocalization. Indirect immunofluorescence labeling also supports a change in membrane distribution for McTIP1;2 and the appearance of a unique compartment where McTIP1;2 is expressed. Mannitol-induced redistribution of McTIP1;2 was arrested by pretreatment with brefeldin A, wortmannin, and cytochalasin D, inhibitors of vesicle trafficking-related processes. Evidence suggests a role for glycosylation and involvement of a cAMP-dependent signaling pathway in McTIP1;2 redistribution. McTIP1;2 redistribution to endosomal compartments may be part of a homeostatic process to restore and maintain cellular osmolarity under osmotic-stress conditions. PMID:15299122

  20. Glucose Monitoring System Based on Osmotic Pressure Measurements

    Directory of Open Access Journals (Sweden)

    Alexandra LEAL

    2011-02-01

    Full Text Available This paper presents the design and development of a prototype sensor unit for implementation in a long-term glucose monitoring system suitable for estimating glucose levels in people suffering from diabetes mellitus. The system utilizes osmotic pressure as the sensing mechanism and consists of a sensor prototype that is integrated together with a pre-amplifier and data acquisition unit for both data recording and processing. The sensor prototype is based on an embedded silicon absolute pressure transducer and a semipermeable nanoporous membrane that is enclosed in the sensor housing. The glucose monitoring system facilitates the integration of a low power microcontroller that is combined with a wireless inductive powered communication link. Experimental verification have proven that the system is capable of tracking osmotic pressure changes using albumin as a model compound, and thereby show a proof of concept for novel long term tracking of blood glucose from remote sensor nodes.

  1. The fragile X protein binds mRNAs involved in cancer progression and modulates metastasis formation.

    Science.gov (United States)

    Lucá, Rossella; Averna, Michele; Zalfa, Francesca; Vecchi, Manuela; Bianchi, Fabrizio; La Fata, Giorgio; Del Nonno, Franca; Nardacci, Roberta; Bianchi, Marco; Nuciforo, Paolo; Munck, Sebastian; Parrella, Paola; Moura, Rute; Signori, Emanuela; Alston, Robert; Kuchnio, Anna; Farace, Maria Giulia; Fazio, Vito Michele; Piacentini, Mauro; De Strooper, Bart; Achsel, Tilmann; Neri, Giovanni; Neven, Patrick; Evans, D Gareth; Carmeliet, Peter; Mazzone, Massimiliano; Bagni, Claudia

    2013-10-01

    The role of the fragile X mental retardation protein (FMRP) is well established in brain, where its absence leads to the fragile X syndrome (FXS). FMRP is almost ubiquitously expressed, suggesting that, in addition to its effects in brain, it may have fundamental roles in other organs. There is evidence that FMRP expression can be linked to cancer. FMR1 mRNA, encoding FMRP, is overexpressed in hepatocellular carcinoma cells. A decreased risk of cancer has been reported in patients with FXS while a patient-case with FXS showed an unusual decrease of tumour brain invasiveness. However, a role for FMRP in regulating cancer biology, if any, remains unknown. We show here that FMRP and FMR1 mRNA levels correlate with prognostic indicators of aggressive breast cancer, lung metastases probability and triple negative breast cancer (TNBC). We establish that FMRP overexpression in murine breast primary tumours enhances lung metastasis while its reduction has the opposite effect regulating cell spreading and invasion. FMRP binds mRNAs involved in epithelial mesenchymal transition (EMT) and invasion including E-cadherin and Vimentin mRNAs, hallmarks of EMT and cancer progression. © 2013 The Authors. Published by John Wiley and Sons, Ltd on behalf of EMBO.

  2. Family Environment and Behavior Problems in Children, Adolescents, and Adults with Fragile X Syndrome

    Science.gov (United States)

    Greenberg, Jan S.; Seltzer, Marsha Mailick; Baker, Jason K.; Smith, Leann E.; Warren, Steven F.; Brady, Nancy; Hong, Jinkuk

    2012-01-01

    We examine how the family environment is associated with aspects of the Fragile X syndrome phenotype during childhood, adolescence, and adulthood. Mothers of children (n = 48), adolescents (n = 85), and adults (n = 34) with Fragile X syndrome participated in a multisite study. For children and adults with Fragile X syndrome, the presence of warmth…

  3. Flap Endonuclease 1 Limits Telomere Fragility on the Leading Strand*

    Science.gov (United States)

    Teasley, Daniel C.; Parajuli, Shankar; Nguyen, Mai; Moore, Hayley R.; Alspach, Elise; Lock, Ying Jie; Honaker, Yuchi; Saharia, Abhishek; Piwnica-Worms, Helen; Stewart, Sheila A.

    2015-01-01

    The existence of redundant replication and repair systems that ensure genome stability underscores the importance of faithful DNA replication. Nowhere is this complexity more evident than in challenging DNA templates, including highly repetitive or transcribed sequences. Here, we demonstrate that flap endonuclease 1 (FEN1), a canonical lagging strand DNA replication protein, is required for normal, complete leading strand replication at telomeres. We find that the loss of FEN1 nuclease activity, but not DNA repair activities, results in leading strand-specific telomere fragility. Furthermore, we show that FEN1 depletion-induced telomere fragility is increased by RNA polymerase II inhibition and is rescued by ectopic RNase H1 expression. These data suggest that FEN1 limits leading strand-specific telomere fragility by processing RNA:DNA hybrid/flap intermediates that arise from co-directional collisions occurring between the replisome and RNA polymerase. Our data reveal the first molecular mechanism for leading strand-specific telomere fragility and the first known role for FEN1 in leading strand DNA replication. Because FEN1 mutations have been identified in human cancers, our findings raise the possibility that unresolved RNA:DNA hybrid structures contribute to the genomic instability associated with cancer. PMID:25922071

  4. Correlation and prediction of osmotic coefficient and water activity of aqueous electrolyte solutions by a two-ionic parameter model

    International Nuclear Information System (INIS)

    Pazuki, G.R.

    2005-01-01

    In this study, osmotic coefficients and water activities in aqueous solutions have been modeled using a new approach based on the Pitzer model. This model contains two physically significant ionic parameters regarding ionic solvation and the closest distance of approach between ions in a solution. The proposed model was evaluated by estimating the osmotic coefficients of nine electrolytes in aqueous solutions. The obtained results showed that the model is suitable for predicting the osmotic coefficients in aqueous electrolyte solutions. Using adjustable parameters, which have been calculated from regression between the experimental osmotic coefficient and the results of this model, the water activity coefficients of aqueous solutions were calculated. The average absolute relative deviations of the osmotic coefficients between the experimental data and the calculated results were in agreement

  5. Fragile Elite

    DEFF Research Database (Denmark)

    Bregnbæk, Susanne

    China's One Child Policy and its rigorous national focus on educational testing are well known. But what happens to those "lucky" few at the very top of the pyramid? Fragile Elite explores the contradictions of being an elite student through ethnographic research conducted at two top universities...... in China. It uncovers the intimate psychological strains students suffer under the pressure imposed on them by parents and state, where the state acts as a parent, and the parents sometimes reinforce the state. The book offers insights into the intergenerational tensions as work in relation to the ongoing...... shifts in educational policy and definition of what a "quality" student, child, and citizen is in contemporary China....

  6. Analysis of unsaturated clayey materials hydration incorporating the effect of thermo-osmotic flow

    International Nuclear Information System (INIS)

    Sanchez, M.; Arson, C.

    2012-01-01

    approximately twice smaller in this zone than the saturation degree obtained with the reference behavior model. This means that thermo-osmosis originates drying. During the 1000 years of nuclear waste storage, the host rock is thus expected to be subjected to more significant drying if thermo-osmosis is taken into account. This is because the equivalent thermal conductivity of the unsaturated porous medium, computed as a weighted average of the thermal conductivities of all constituents (solid skeleton, liquid, gas), is expected to be lower than in the reference model (due to its lower saturation). Heat flux is mainly controlled by Fourier's law; so if a given heat flux is imposed at the surfaces of the heating source, the decrease of equivalent thermal conductivity has to be compensated by the gradient of temperature. The massif studied with the thermo-osmotic model being dryer than in the reference case, it is thus logical to observe higher temperatures around the heating source in the simulation accounting for thermo-osmotic effects. As it can be observed, the effect of thermo-osmotic flow is relevant in this problem related to nuclear waste disposals. (authors)

  7. Extracellular-matrix-mediated osmotic pressure drives Vibrio cholerae biofilm expansion and cheater exclusion

    OpenAIRE

    Yan, Jing; Nadell, Carey D.; Stone, Howard A.; Wingreen, Ned S.; Bassler, Bonnie L.

    2017-01-01

    Biofilms, surface-attached communities of bacteria encased in an extracellular matrix, are a major mode of bacterial life. How the material properties of the matrix contribute to biofilm growth and robustness is largely unexplored, in particular in response to environmental perturbations such as changes in osmotic pressure. Here, using Vibrio cholerae as our model organism, we show that during active cell growth, matrix production enables biofilm-dwelling bacterial cells to establish an osmot...

  8. The Role of Chain Length in Nonergodicity Factor and Fragility of Polymers

    DEFF Research Database (Denmark)

    Dalle-Ferrie, Cecile; Niss, Kristine; Sokolov, Alexei

    2010-01-01

    The mechanism that leads to different fragility values upon approaching the glass transition remains a topic of active discussion. Many researchers are trying to find an answer in the properties of the frozen glassy state. Following this approach, we focus here on a previously proposed relationship...... between the fragility of glass-formers and their nonergodicity factor, determined by inelastic X-ray scattering (IXS) in the glass. We extend this molecular liquid study to two model polymers— polystyrene (PS) and polyisobutylene (PIB)—for which we change the molecular weight. Polymers offer...... the opportunity to change the fragility without altering the chemical structure, just by changing the chain length. Thus, we specifically chose PS and PIB because they exhibit opposite dependences of fragility with molecular weight. Our analysis for these two polymers reveals no unique correlation between...

  9. Osmotic potential calculations of inorganic and organic aqueous solutions over wide solute concentration levels and temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Cochrane, T. T., E-mail: agteca@hotmail.com [AGTECA S.A., 230 Oceanbeach Road, Mount Maunganui, Tauranga 3116 (New Zealand); Cochrane, T. A., E-mail: tom.cochrane@canterbury.ac.nz [Department of Civil and Natural Resources Engineering, University of Canterbury, Private Bag 4800, Christchurch 8140 (New Zealand)

    2016-01-15

    Purpose: To demonstrate that the authors’ new “aqueous solution vs pure water” equation to calculate osmotic potential may be used to calculate the osmotic potentials of inorganic and organic aqueous solutions over wide ranges of solute concentrations and temperatures. Currently, the osmotic potentials of solutions used for medical purposes are calculated from equations based on the thermodynamics of the gas laws which are only accurate at low temperature and solute concentration levels. Some solutions used in medicine may need their osmotic potentials calculated more accurately to take into account solute concentrations and temperatures. Methods: The authors experimented with their new equation for calculating the osmotic potentials of inorganic and organic aqueous solutions up to and beyond body temperatures by adjusting three of its factors; (a) the volume property of pure water, (b) the number of “free” water molecules per unit volume of solution, “N{sub f},” and (c) the “t” factor expressing the cooperative structural relaxation time of pure water at given temperatures. Adequate information on the volume property of pure water at different temperatures is available in the literature. However, as little information on the relative densities of inorganic and organic solutions, respectively, at varying temperatures needed to calculate N{sub f} was available, provisional equations were formulated to approximate values. Those values together with tentative t values for different temperatures chosen from values calculated by different workers were substituted into the authors’ equation to demonstrate how osmotic potentials could be estimated over temperatures up to and beyond bodily temperatures. Results: The provisional equations formulated to calculate N{sub f}, the number of free water molecules per unit volume of inorganic and organic solute solutions, respectively, over wide concentration ranges compared well with the calculations of N{sub f

  10. Osmotic potential calculations of inorganic and organic aqueous solutions over wide solute concentration levels and temperatures

    International Nuclear Information System (INIS)

    Cochrane, T. T.; Cochrane, T. A.

    2016-01-01

    Purpose: To demonstrate that the authors’ new “aqueous solution vs pure water” equation to calculate osmotic potential may be used to calculate the osmotic potentials of inorganic and organic aqueous solutions over wide ranges of solute concentrations and temperatures. Currently, the osmotic potentials of solutions used for medical purposes are calculated from equations based on the thermodynamics of the gas laws which are only accurate at low temperature and solute concentration levels. Some solutions used in medicine may need their osmotic potentials calculated more accurately to take into account solute concentrations and temperatures. Methods: The authors experimented with their new equation for calculating the osmotic potentials of inorganic and organic aqueous solutions up to and beyond body temperatures by adjusting three of its factors; (a) the volume property of pure water, (b) the number of “free” water molecules per unit volume of solution, “N f ,” and (c) the “t” factor expressing the cooperative structural relaxation time of pure water at given temperatures. Adequate information on the volume property of pure water at different temperatures is available in the literature. However, as little information on the relative densities of inorganic and organic solutions, respectively, at varying temperatures needed to calculate N f was available, provisional equations were formulated to approximate values. Those values together with tentative t values for different temperatures chosen from values calculated by different workers were substituted into the authors’ equation to demonstrate how osmotic potentials could be estimated over temperatures up to and beyond bodily temperatures. Results: The provisional equations formulated to calculate N f , the number of free water molecules per unit volume of inorganic and organic solute solutions, respectively, over wide concentration ranges compared well with the calculations of N f using recorded

  11. Divergent effects of obesity on fragility fractures

    Directory of Open Access Journals (Sweden)

    Caffarelli C

    2014-09-01

    Full Text Available Carla Caffarelli, Chiara Alessi, Ranuccio Nuti, Stefano Gonnelli Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy Abstract: Obesity was commonly thought to be advantageous for maintaining healthy bones due to the higher bone mineral density observed in overweight individuals. However, several recent studies have challenged the widespread belief that obesity is protective against fracture and have suggested that obesity is a risk factor for certain fractures. The effect of obesity on fracture risk is site-dependent, the risk being increased for some fractures (humerus, ankle, upper arm and decreased for others (hip, pelvis, wrist. Moreover, the relationship between obesity and fracture may also vary by sex, age, and ethnicity. Risk factors for fracture in obese individuals appear to be similar to those in nonobese populations, although patterns of falling are particularly important in the obese. Research is needed to determine if and how visceral fat and metabolic complications of obesity (type 2 diabetes mellitus, insulin resistance, chronic inflammation, etc are causally associated with bone status and fragility fracture risk. Vitamin D deficiency and hypogonadism may also influence fracture risk in obese individuals. Fracture algorithms such as FRAX® might be expected to underestimate fracture probability. Studies specifically designed to evaluate the antifracture efficacy of different drugs in obese patients are not available; however, literature data may suggest that in obese patients higher doses of the bisphosphonates might be required in order to maintain efficacy against nonvertebral fractures. Therefore, the search for better methods for the identification of fragility fracture risk in the growing population of adult and elderly subjects with obesity might be considered a clinical priority which could improve the prevention of fracture in obese individuals. Keywords: bone mineral density, BMI

  12. Influence of carbide precipitation upon hydrogen fragilization of an AISI 304 steel

    International Nuclear Information System (INIS)

    Hazarabedian, A.E.; Ovejero Garcia, J.

    1991-01-01

    The present work deals with austenitic stainless steels for a family of steels that is renowned for its high resistance to hydrogen fragilization. Nevertheless, these steels may suffer hydrogen fragilization under severe working conditions. This fact is strongly dependent on many factors -composition, grain size, other phases present, corrosion sensitivity, etc.-. While there are studies that show how intergranular corrosion is influenced by corrosion sensitivity -mainly due to carbide precipitation in grain boundaries-, there are no reports about the effect of the carbide precipitation itself on hydrogen fragilization for these steels. (Author) [es

  13. On the pressure dependence of the fragility of glycerol

    Energy Technology Data Exchange (ETDEWEB)

    Pawlus, S; Paluch, M; Ziolo, J [Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Roland, C M [Naval Research Laboratory, Chemistry Division, Code 6120, Washington, DC 20375-5342 (United States)

    2009-08-19

    This work was motivated by ostensibly contradictory results from different groups regarding the effect of pressure on the fragility of glycerol. We present new experimental data for an intermediate pressure regime showing that the fragility increases with pressure up to about 1.8 GPa, becoming invariant at higher pressures. There is no discrepancy among the various literature data taken in toto. The behavior of glycerol is quite distinct from that of normal liquids, a result of its substantial hydrogen bonding. (fast track communication)

  14. Balancing Osmotic Pressure of Electrolytes for Nanoporous Membrane Vanadium Redox Flow Battery with a Draw Solute.

    Science.gov (United States)

    Yan, Ligen; Li, Dan; Li, Shuaiqiang; Xu, Zhi; Dong, Junhang; Jing, Wenheng; Xing, Weihong

    2016-12-28

    Vanadium redox flow batteries with nanoporous membranes (VRFBNM) have been demonstrated to be good energy storage devices. Yet the capacity decay due to permeation of vanadium and water makes their commercialization very difficult. Inspired by the forward osmosis (FO) mechanism, the VRFBNM battery capacity decrease was alleviated by adding a soluble draw solute (e.g., 2-methylimidazole) into the catholyte, which can counterbalance the osmotic pressure between the positive and negative half-cell. No change of the electrolyte volume has been observed after VRFBNM being operated for 55 h, revealing that the permeation of water and vanadium ions was effectively limited. Consequently, the Coulombic efficiency (CE) of nanoporous TiO 2 vanadium redox flow battery (VRFB) was enhanced from 93.5% to 95.3%, meanwhile, its capacity decay was significantly suppressed from 60.7% to 27.5% upon the addition of soluble draw solute. Moreover, the energy capacity of the VRFBNM was noticeably improved from 297.0 to 406.4 mAh remarkably. These results indicate balancing the osmotic pressure via the addition of draw solute can restrict pressure-dependent vanadium permeation and it can be established as a promising method for up-scaling VRFBNM application.

  15. Behavioral Intervention for Problem Behavior in Children with Fragile X Syndrome

    Science.gov (United States)

    Moskowitz, Lauren J.; Carr, Edward G.; Durand, V. Mark

    2011-01-01

    Parents and professionals typically report problem behavior as a significant concern for children with fragile X syndrome. In the present study, the authors explored whether behaviorally based interventions would result in a reduction in problem behavior and an improvement in quality of life for 3 children with fragile X syndrome and their…

  16. Fragile X syndrome in two siblings with major congenital malformations

    Energy Technology Data Exchange (ETDEWEB)

    Giampietro, P.F.; Haas, B.R.; Lipper, E. [Cornell Univ. Medical Center, New York, NY (United States)] [and others

    1996-05-17

    We report on 2 brothers with both fragile X and VACTERL-H syndrome. The first sibling, age 5, had bilateral cleft lip and palate, ventricular septal defect, and a hypoplastic thumb. The second sibling, age 2{1/2}, had a trachesophageal fistula, esophageal atresia, and vertebral abnormality. High-resolution chromosome analysis showed a 46,XY chromosome constitution in both siblings. By PCR and Southern blot analysis, the siblings were found to have large triplet repeat expansions in the fragile X gene (FMR 1) and both had methylation mosaicism. Enzyme kinetic studies of iduronate sulfatase demonstrated a two-fold increase in activity in the first sib as compared to the second. Possible mechanisms through which the fragile X mutation can cause down-regulation of adjacent loci are discussed. 24 refs., 4 figs.

  17. Live birth following serial vitrification of embryos and PGD for fragile X syndrome in a patient with the premutation and decreased ovarian reserve.

    Science.gov (United States)

    Nayot, Dan; Chung, Jin Tae; Son, Weon-Young; Ao, Assangla; Hughes, Mark; Dahan, Michael H

    2013-11-01

    To present a live birth resulting from serial vitrification of embryos and pre-implantation genetic diagnosis (PGD). A 31-year-old with primary infertility, fragile-X premutation, and decreased ovarian reserve (DOR) (baseline FSH level 33 IU/L), presented after failing to stimulate to follicle diameters >10 mm with three cycles of invitro fertilization (IVF). After counseling, the couple opted for serial in-vitro maturation (IVM), embryo vitrification, and genetic testing using array comparative genomic hybridization (aCGH) and PGD. Embryos were vitrified 2 days after intra-cytoplasmic sperm injection (ICSI). Thawed embryos were biopsied on day-three and transferred on day-five. The couple underwent 20 cycles of assisted reproductive technology. A total of 23 in-vivo mature and five immature oocytes were retrieved, of which one matured in-vitro. Of 24 embryos, 17/24 (71 %) developed to day two and 11/24 (46 %) survived to blastocyst stage with a biopsy result available. Four blastocysts had normal PGD and aCGH results. Both single embryo transfers resulted in a successful implantation, one a blighted ovum and the other in a live birth. Young patients with DOR have potential for live birth as long as oocytes can be obtained and embryos created. Serial vitrification may be the mechanism of choice in these patients when PGD is needed.

  18. The roles of different salts and a novel osmotic pressure control strategy for improvement of DHA production by Schizochytrium sp.

    Science.gov (United States)

    Hu, Xue-Chao; Ren, Lu-Jing; Chen, Sheng-Lan; Zhang, Li; Ji, Xiao-Jun; Huang, He

    2015-11-01

    The effects of different osmotic pressure, changed by six salts (NaCl, Na2SO4, (NH4)2SO4, KH2PO4 and MSG), on cell growth and DHA synthesis by Schizochytrium sp. were investigated. Six optimal mediums were obtained to study different osmotic pressure combinations at cell growth stage and DHA synthesis stage. Results showed that cultivated cell in higher osmotic pressure condition and fermented in lower osmotic pressure condition was benefit to enhance DHA synthesis. Combination 17-6 could get the maximum cell dry weight of 56.95 g/L and the highest DHA percentage in total fatty acids of 55.21%, while combination 17-B could get the highest lipid yield of 33.47 g/L with 42.10% DHA in total fatty acids. This was the first report about the enhancement of DHA production by osmotic regulation and this work provided two novel osmotic control processes for high lipid yield and high DHA percentage in total fatty acids.

  19. Stress responses of the industrial workhorse Bacillus licheniformis to osmotic challenges.

    Directory of Open Access Journals (Sweden)

    Rebecca Schroeter

    Full Text Available The Gram-positive endospore-forming bacterium Bacillus licheniformis can be found widely in nature and it is exploited in industrial processes for the manufacturing of antibiotics, specialty chemicals, and enzymes. Both in its varied natural habitats and in industrial settings, B. licheniformis cells will be exposed to increases in the external osmolarity, conditions that trigger water efflux, impair turgor, cause the cessation of growth, and negatively affect the productivity of cell factories in biotechnological processes. We have taken here both systems-wide and targeted physiological approaches to unravel the core of the osmostress responses of B. licheniformis. Cells were suddenly subjected to an osmotic upshift of considerable magnitude (with 1 M NaCl, and their transcriptional profile was then recorded in a time-resolved fashion on a genome-wide scale. A bioinformatics cluster analysis was used to group the osmotically up-regulated genes into categories that are functionally associated with the synthesis and import of osmostress-relieving compounds (compatible solutes, the SigB-controlled general stress response, and genes whose functional annotation suggests that salt stress triggers secondary oxidative stress responses in B. licheniformis. The data set focusing on the transcriptional profile of B. licheniformis was enriched by proteomics aimed at identifying those proteins that were accumulated by the cells through increased biosynthesis in response to osmotic stress. Furthermore, these global approaches were augmented by a set of experiments that addressed the synthesis of the compatible solutes proline and glycine betaine and assessed the growth-enhancing effects of various osmoprotectants. Combined, our data provide a blueprint of the cellular adjustment processes of B. licheniformis to both sudden and sustained osmotic stress.

  20. Stress responses of the industrial workhorse Bacillus licheniformis to osmotic challenges.

    Science.gov (United States)

    Schroeter, Rebecca; Hoffmann, Tamara; Voigt, Birgit; Meyer, Hanna; Bleisteiner, Monika; Muntel, Jan; Jürgen, Britta; Albrecht, Dirk; Becher, Dörte; Lalk, Michael; Evers, Stefan; Bongaerts, Johannes; Maurer, Karl-Heinz; Putzer, Harald; Hecker, Michael; Schweder, Thomas; Bremer, Erhard

    2013-01-01

    The Gram-positive endospore-forming bacterium Bacillus licheniformis can be found widely in nature and it is exploited in industrial processes for the manufacturing of antibiotics, specialty chemicals, and enzymes. Both in its varied natural habitats and in industrial settings, B. licheniformis cells will be exposed to increases in the external osmolarity, conditions that trigger water efflux, impair turgor, cause the cessation of growth, and negatively affect the productivity of cell factories in biotechnological processes. We have taken here both systems-wide and targeted physiological approaches to unravel the core of the osmostress responses of B. licheniformis. Cells were suddenly subjected to an osmotic upshift of considerable magnitude (with 1 M NaCl), and their transcriptional profile was then recorded in a time-resolved fashion on a genome-wide scale. A bioinformatics cluster analysis was used to group the osmotically up-regulated genes into categories that are functionally associated with the synthesis and import of osmostress-relieving compounds (compatible solutes), the SigB-controlled general stress response, and genes whose functional annotation suggests that salt stress triggers secondary oxidative stress responses in B. licheniformis. The data set focusing on the transcriptional profile of B. licheniformis was enriched by proteomics aimed at identifying those proteins that were accumulated by the cells through increased biosynthesis in response to osmotic stress. Furthermore, these global approaches were augmented by a set of experiments that addressed the synthesis of the compatible solutes proline and glycine betaine and assessed the growth-enhancing effects of various osmoprotectants. Combined, our data provide a blueprint of the cellular adjustment processes of B. licheniformis to both sudden and sustained osmotic stress.

  1. Essays on financial fragility and regulation

    NARCIS (Netherlands)

    Ma, K.

    2013-01-01

    This thesis investigates various issues in regulation, with three chapters on financial fragility and banking regulation, and one chapter on competition policy. Chapter 2 studies banks’ herding driven by their need for market liquidity, highlighting a trade-off between systemic risk and liquidity

  2. Estimating contribution of anthocyanin pigments to osmotic adjustment during winter leaf reddening.

    Science.gov (United States)

    Hughes, Nicole M; Carpenter, Kaylyn L; Cannon, Jonathan G

    2013-01-15

    The association between plant water stress and synthesis of red, anthocyanin pigments in leaves has led some plant biologists to propose an osmotic function of leaf reddening. According to this hypothesis, anthocyanins function as a solute in osmotic adjustment (OA), contributing to depression of osmotic potential (Ψ(π)) and maintenance of turgor pressure during drought-stressed conditions. Here we calculate the percent contribution of anthocyanin to leaf Ψ(π) during OA in two angiosperm evergreen species, Galax urceolata and Gaultheria procumbens. Both species exhibit dramatic leaf reddening under high light during winter, concomitant with declines in leaf water potential and accumulation of solutes. Data previously published by the authors on osmotic potential at full turgor (Ψ(π,100)) of G. urceolata and G. procumbens leaves before and after leaf reddening were used to estimate OA. In vivo molar concentrations of anthocyanin, glucose, fructose, and sucrose measured from the same individuals were converted to pressure equivalents using the Ideal Gas Law, and percent contribution to OA was estimated. Estimated mean OA during winter was -0.7MPa for G. urceolata and -0.8MPa for G. procumbens. In vivo concentrations of anthocyanin (3-10mM) were estimated to account for ∼2% of OA during winter, and comprised <0.7% of Ψ(π,100) in both species. Glucose, fructose, and sucrose combined accounted for roughly 50 and 80% of OA for G. urceolata and G. procumbens, respectively, and comprised ∼20% of Ψ(π,100). We observed that a co-occurring, acyanic species (Vinca minor) achieved similar OA without synthesizing anthocyanin. We conclude that anthocyanins represent a measurable, albeit meager, component of OA in red-leafed evergreen species during winter. However, due to their low concentrations, metabolic costliness relative to other osmolytes, and striking red color (unnecessary for an osmotic function), it is unlikely that they are synthesized solely for an

  3. Managing Public Finance and Procurement in Fragile and Conflicted Settings

    OpenAIRE

    Porter, Doug; Andrews, Matt; Turkewitz, Joel; Wescotttz, Clay

    2011-01-01

    Discusses ways to enhance the incentives for elites to invest political capital in achieving (1) functional results through the formal public finance management (PFM) system; (2) the effectiveness of agencies responsible for services and regulating activities; and (3) better performance of civil service officials. Using the Public Expenditure and Financial Accountability (PEFA) Performance Measurement Framework, countries affected by conflict and fragility can be compared with non-fragile poo...

  4. RBC deformability and amino acid concentrations after hypo-osmotic challenge may reflect chronic cell hydration status in healthy young men

    Science.gov (United States)

    Stookey, Jodi D; Klein, Alexis; Hamer, Janice; Chi, Christine; Higa, Annie; Ng, Vivian; Arieff, Allen; Kuypers, Frans A; Larkin, Sandra; Perrier, Erica; Lang, Florian

    2013-01-01

    Biomarkers of chronic cell hydration status are needed to determine whether chronic hyperosmotic stress increases chronic disease risk in population-representative samples. In vitro, cells adapt to chronic hyperosmotic stress by upregulating protein breakdown to counter the osmotic gradient with higher intracellular amino acid concentrations. If cells are subsequently exposed to hypo-osmotic conditions, the adaptation results in excess cell swelling and/or efflux of free amino acids. This study explored whether increased red blood cell (RBC) swelling and/or plasma or urine amino acid concentrations after hypo-osmotic challenge might be informative about relative chronic hyperosmotic stress in free-living men. Five healthy men (20–25 years) with baseline total water intake below 2 L/day participated in an 8-week clinical study: four 2-week periods in a U-shaped A-B-C-A design. Intake of drinking water was increased by +0.8 ± 0.3 L/day in period 2, and +1.5 ± 0.3 L/day in period 3, and returned to baseline intake (0.4 ± 0.2 L/day) in period 4. Each week, fasting blood and urine were collected after a 750 mL bolus of drinking water, following overnight water restriction. The periods of higher water intake were associated with significant decreases in RBC deformability (index of cell swelling), plasma histidine, urine arginine, and urine glutamic acid. After 4 weeks of higher water intake, four out of five participants had ½ maximal RBC deformability below 400 mmol/kg; plasma histidine below 100 μmol/L; and/or undetectable urine arginine and urine glutamic acid concentrations. Work is warranted to pursue RBC deformability and amino acid concentrations after hypo-osmotic challenge as possible biomarkers of chronic cell hydration. PMID:24303184

  5. Osmotic and apparent molar properties of binary mixtures alcohol + 1-butyl-3-methylimidazolium trifluoromethanesulfonate ionic liquid

    International Nuclear Information System (INIS)

    González, Emilio J.; Calvar, Noelia; Domínguez, Ángeles; Macedo, Eugénia A.

    2013-01-01

    Highlights: ► Osmotic and physical properties of binary mixtures {alcohol + [BMim][TfO]} were measured. ► From experimental data, apparent molar properties and osmotic coefficients were calculated. ► The apparent properties were fitted using a Redlich–Meyer type equation. ► The osmotic coefficients were correlated using the Extended Pitzer model. -- Abstract: In this work, physical properties (densities and speeds of sound) for the binary systems {1-propanol, or 2-propanol, or 1-butanol, or 2-butanol, or 1-pentanol + 1-butyl-3-methylimidazolium trifluoromethanesulfonate} were experimentally measured from T = (293.15 to 323.15) K and at atmospheric pressure. These data were used to calculate the apparent molar volume and apparent molar isentropic compression which were fitted to a Redlich–Meyer type equation. This fit was used to obtain the corresponding apparent molar properties at infinite dilution. On the other hand, the osmotic and activity coefficients and vapor pressures of these binary mixtures were also determined at T = 323.15 K using the vapor pressure osmometry technique. The Extended Pitzer model of Archer was employed to correlate the experimental osmotic coefficients. From the parameters obtained in the correlation, the mean molal activity coefficients and the excess Gibbs free energy for the studied mixtures were calculated

  6. Efficiency of osmotic pipe flows

    DEFF Research Database (Denmark)

    Haaning, Louise Sejling; Jensen, Kaare Hartvig; Helix Nielsen, Claus

    2013-01-01

    efficiency of these flows is limited by the presence of “unstirred” concentration boundary layers near the tube walls, and our primary aim is to understand and quantify these layers and their effect on the flow. We measure the outlet flow rate Qout while varying the inlet flow rate Q*, concentration c......We present experiments and theory for flows of sugar or salt solutions in cylindrical tubes with semipermeable walls (hollow fiber membranes) immersed in water, quantifying the strength of the osmotic driving force in relation to the dimensionless parameters that specify the system. The pumping...

  7. Influence of osmotic processes on the excess-hydraulic head measured in the Toarcian/Domerian argillaceous formation of Tournemire

    International Nuclear Information System (INIS)

    Tremosa, J.

    2010-01-01

    In the framework of the studies dealing on ability to store radioactive wastes in argillaceous formations, signification of interstitial pressures is an important point to understand water and solutes transport. In very low permeability argillaceous formations, like those studied in the Callovo-Oxfordian of the Paris basin by ANDRA, pore pressure is frequently higher than the theoretical hydrostatic pressure or than the pressure in the surrounding aquifers. Such an overpressure is also measured in the Toarcian/Domerian argillaceous formation (k = 10 -21 m 2 ), studied by the IRSN in the underground research laboratory of Tournemire (Aveyron, France). The hydraulic head profile has been specified in this manuscript and found to present a 30 ±10 m excess head. This excess-head can be due to compaction disequilibrium of the argillaceous formation, diagenetic evolution of the rock, tectonic compression, changes in hydrodynamic boundary conditions or osmotic processes. Amongst these potential causes, chemical osmosis and thermo-osmosis, a fluid flow under a chemical concentration and a temperature gradient, respectively, are expected to develop owing to the small pore size and the electrostatic interactions related to the charged surface of clay minerals. The goal of the work presented here was to study and quantify the contribution of each cause to the measured excess-head. Chemo-osmotic and thermo-osmotic permeabilities were obtained by experiments and using theoretical models. Theoretical models are based on the reproduction of the interactions occurring between the charged surface of clay minerals and pore solution and their up-scaling at the representative elementary volume macroscopic scale. Chemical osmosis phenomenon is related to anionic exclusion and the determination of the chemo-osmotic efficiency requires the resolution of an electrical interactions model. A triple-layer-model which considers diffuse layers overlapping was improved during this thesis to be

  8. Fragility Modeling of Aging Containment Metallic Pressure Boundaries

    International Nuclear Information System (INIS)

    Cherry, J.L.; Ellingwood, B.R.

    1999-01-01

    The containment in a nuclear power plant (NPP) provides a barrier against the release of radioactivity in the event of an accident. Corrosion that has been observed in some steel containments and liners of reinforced concrete containments has raised questions about their ability to perform this function. The performance of corroded containments during events at or beyond the design basis is impacted by numerous sources of uncertainty. A fragility model of the containment provides a relatively simple depiction of the impact of uncertainties on structural performance and a basis for decision-making in the presence of uncertainty. Moreover, it is a necessary ingredient of any time-dependent structural reliability analysis. A nonlinear finite element analysis of containment response furnishes the necessary platform to perform numerical experiments to determine containment fragility. A statistically-based sampling plan minimizes the finite element computations required to develop the fragility curve. The -percentile (or other fractile) then gives a statistically based indication of the lower bound on containment capacity, and can be used as a screening tool to determine whether more refined further analysis or tests to support service life evaluations are warranted

  9. Large germinoma in basal ganglia treated by intraarterial chemotherapy with ACNU following osmotic blood-brain barrier disruption and radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Miyagami, Mitsusuke; Tsubokawa, Takashi; Kobayashi, Makio.

    1988-10-01

    A rare case of large germinoma in the basal ganglia is reported which was effectively treated by intracarotid chemotherapy with ACNU following osmotic blood-brain barrier disruption using 20 % mannitol and radiation therapy. A 19-year-old man displayed slowly progressive right hemiparesis, motor aphasia and predementia on admission. Plain CT demonstrated a tumor which had a slightly high density with intratumoral calcification and a small cyst, and slight to moderate enhancement was observed following intravenous injection of contrast medium, but there was no unilateral ventricular enlargement. Cerebral angiography revealed hypervascular tumor staining with early draining veins. After biopsy, and as a result of intracarotid chemotherapy with ACNU following osmotic blood-brain barrier disruption and radiation therapy, the tumor decreased rapidly to about 20 % of its original mass. After discharge, tumor progression was observed. However, the enlarged tumor mass almost disappeared (except for calcification) on CT with clinical improvement in response to intracarotid chemotherapy with ACNU following 20 % mannitol.

  10. Flap Endonuclease 1 Limits Telomere Fragility on the Leading Strand.

    Science.gov (United States)

    Teasley, Daniel C; Parajuli, Shankar; Nguyen, Mai; Moore, Hayley R; Alspach, Elise; Lock, Ying Jie; Honaker, Yuchi; Saharia, Abhishek; Piwnica-Worms, Helen; Stewart, Sheila A

    2015-06-12

    The existence of redundant replication and repair systems that ensure genome stability underscores the importance of faithful DNA replication. Nowhere is this complexity more evident than in challenging DNA templates, including highly repetitive or transcribed sequences. Here, we demonstrate that flap endonuclease 1 (FEN1), a canonical lagging strand DNA replication protein, is required for normal, complete leading strand replication at telomeres. We find that the loss of FEN1 nuclease activity, but not DNA repair activities, results in leading strand-specific telomere fragility. Furthermore, we show that FEN1 depletion-induced telomere fragility is increased by RNA polymerase II inhibition and is rescued by ectopic RNase H1 expression. These data suggest that FEN1 limits leading strand-specific telomere fragility by processing RNA:DNA hybrid/flap intermediates that arise from co-directional collisions occurring between the replisome and RNA polymerase. Our data reveal the first molecular mechanism for leading strand-specific telomere fragility and the first known role for FEN1 in leading strand DNA replication. Because FEN1 mutations have been identified in human cancers, our findings raise the possibility that unresolved RNA:DNA hybrid structures contribute to the genomic instability associated with cancer. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Seismic fragility analysis of the block masonry wall in nuclear power plants

    International Nuclear Information System (INIS)

    Wang, Z-L.; Pandey, M.D.; Xie, X-C.

    2014-01-01

    The evaluation of seismic fragility of a structure is an integral part in the Seismic Probabilistic Risk Analysis (SPRA). The block masonry wall, a commonly used barrier in nuclear power plants, is fairly vulnerable to failure under an earthquake. In practice, the seismic fragility of block walls is commonly evaluated using a simple deterministic approach called Conservative Deterministic Failure Margin (CDFM) method. This paper presents a more formal fragility analysis of a block wall based on rigorous probabilistic methods and the accuracy of the CDFM method is evaluated by comparison to the more rigorous FA method. (author)

  12. [Extrapontine osmotic myelinolysis].

    Science.gov (United States)

    Silva, Federico A; Rueda-Clausen, Christian F; Ramírez, Fabián

    2005-06-01

    Extrapontine osmotic myelinolysis is a rare nervous system complication. Symptoms of this malady were presented during the clinical examination of a 49-year-old alcoholic male, who arrived at the hospital emergency room in a state of cardiorespiratory arrest. After resuscitation methods were applied, the patient was found in metabolic acidosis (pH 7.014) and was treated with sodium bicarbonate. Forty-eight hours later, sodium levels in the patient had risen from 142 to 174 mEq/l. During the period of clinical observation, the patient showed signs of cognitive impairment, disartria, bilateral amaurosis, hyporeflexia and right-half body hemiparesias. After 72 hours, computer tomography was applied; this showed a bilateral lenticular hypodensity with internal and external capsule compromise. One month later, when the patient was referred to another institution for rehabilitation, the patient showed cognitive impairment, bilateral optic atrophy, residual disartria, bradikynesia and double hemiparesia.

  13. Fragility and structure of Al-Cu alloy melts

    International Nuclear Information System (INIS)

    Lv Xiaoqian; Bian Xiufang; Mao Tan; Li Zhenkuan; Guo Jing; Zhao Yan

    2007-01-01

    The dynamic viscosity measurements are performed for Al-Cu alloy melts with different compositions using an oscillating-cup viscometer. The results show that the viscosities of Al-Cu alloy melts increase with the copper content increasing, and also have a correlation with the correlation radius of clusters, which is measured by the high-temperature X-ray diffractometer. It has also been found that the fragilities of superheated melts (M) of hypereutectic Al-Cu alloys increase with the copper content increasing. There exists a relationship between the fragility and the structure in Al-Cu alloy melts. The value of the M reflects the variation of activation energy for viscous flow

  14. Seismic fragility capacity of equipment--horizontal shaft pump test

    International Nuclear Information System (INIS)

    Iijima, T.; Abe, H.; Suzuki, K.

    2005-01-01

    The current seismic fragility capacity of horizontal shaft pump is 1.6 x 9.8 m/s 2 (1.6 g), which was decided from previous vibration tests and we believe that it must have sufficient margin. The purpose of fragility capacity test is to obtain realistic seismic fragility capacity of horizontal shaft pump by vibration tests. Reactor Building Closed Cooling Water (RCW) Pump was tested as a typical horizontal shaft pump, and then bearings and liner rings were tested as important parts to evaluate critical acceleration and dispersion. Regarding RCW pump test, no damage was found, though maximum input acceleration level was 6 x 9.8 m/s 2 (6 g). Some kinds of bearings and liner rings were tested on the element test. Input load was based on seismic motion which was same with the RCW pump test, and maximum load was equivalent to over 20 times of design seismic acceleration. There was not significant damage that caused emergency stop of pump but degradation of surface roughness was found on some kinds of bearings. It would cause reduction of pump life, but such damage on bearings occurred under large seismic load condition that was equivalent to over 10 to 20 g force. Test results show that realistic fragility capacity of horizontal shaft pump would be at least four times as higher as current value which has been used for our seismic PSA. (authors)

  15. Physiologically Based Pharmacokinetic and Absorption Modeling for Osmotic Pump Products.

    Science.gov (United States)

    Ni, Zhanglin; Talattof, Arjang; Fan, Jianghong; Tsakalozou, Eleftheria; Sharan, Satish; Sun, Dajun; Wen, Hong; Zhao, Liang; Zhang, Xinyuan

    2017-07-01

    Physiologically based pharmacokinetic (PBPK) and absorption modeling approaches were employed for oral extended-release (ER) drug products based on an osmotic drug delivery system (osmotic pumps). The purpose was to systemically evaluate the in vivo relevance of in vitro dissolution for this type of formulation. As expected, in vitro dissolution appeared to be generally predictive of in vivo PK profiles, because of the unique feature of this delivery system that the in vitro and in vivo release of osmotic pump drug products is less susceptible to surrounding environment in the gastrointestinal (GI) tract such as pH, hydrodynamic, and food effects. The present study considered BCS (Biopharmaceutics Classification System) class 1, 2, and 3 drug products with half-lives ranging from 2 to greater than 24 h. In some cases, the colonic absorption models needed to be adjusted to account for absorption in the colon. C max (maximum plasma concentration) and AUCt (area under the concentration curve) of the studied drug products were sensitive to changes in colon permeability and segmental GI transit times in a drug product-dependent manner. While improvement of the methodology is still warranted for more precise prediction (e.g., colonic absorption and dynamic movement in the GI tract), the results from the present study further emphasized the advantage of using PBPK modeling in addressing product-specific questions arising from regulatory review and drug development.

  16. Structure and management of tuberculosis control programs in fragile states--Afghanistan, DR Congo, Haiti, Somalia.

    Science.gov (United States)

    Mauch, Verena; Weil, Diana; Munim, Aayid; Boillot, Francois; Coninx, Rudi; Huseynova, Sevil; Powell, Clydette; Seita, Akihiro; Wembanyama, Henriette; van den Hof, Susan

    2010-07-01

    Health care delivery is particularly problematic in fragile states often connected with increased incidence of communicable diseases, among them tuberculosis. This article draws upon experiences in tuberculosis control in four fragile states from which four lessons learned were derived. A structured inventory to extract common themes specific for TB control in fragile states was conducted among twelve providers of technical assistance who have worked in fragile states. The themes were applied to the TB control programs of Afghanistan, DR Congo, Haiti and Somalia during the years 2000-2006. Case notifications and treatment outcomes have increased in all four countries since 2003 (treatment success rates 81-90%). Access to care and case detection however have remained insufficient (case detection rates 39-62%); There are four lessons learned: 1. TB control programs can function in fragile states. 2. National program leadership and stewardship are essential for quality and sustained TB control. 3. Partnerships with non-governmental providers are vital for continuous service delivery; 4. TB control programs in fragile states require consistent donor support. Despite challenges in management, coordination, security, logistics and funding, TB control programs can function in fragile states, but face considerable problems in access to diagnosis and treatment and therefore case detection. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  17. I’m incredible—or am I? : On the socialization of fragile self-views in children

    NARCIS (Netherlands)

    Brummelman, E.

    2015-01-01

    I’m incredible—or am I? This is a recurring and daunting question for children with fragile self-views, whose feelings of self-worth crumble in the face of setbacks. What are the origins of children’s fragile self-views, and how can interventions reduce the fragility of children’s self-views? The

  18. 123 - 128 Sadau et al.

    African Journals Online (AJOL)

    User

    on some haematological parameters and red blood cell osmotic fragility in Wistar rats subjected to water immersion ... peroxidation generates a variety of relatively stable decomposition ... stress.This is because their membrane is rich in.

  19. Effects of rainfall exclusion on leaf gas exchange traits and osmotic adjustment in mature canopy trees of Dryobalanops aromatica (Dipterocarpaceae) in a Malaysian tropical rain forest.

    Science.gov (United States)

    Inoue, Yuta; Ichie, Tomoaki; Kenzo, Tanaka; Yoneyama, Aogu; Kumagai, Tomo'omi; Nakashizuka, Tohru

    2017-10-01

    Climate change exposes vegetation to unusual levels of drought, risking a decline in productivity and an increase in mortality. It still remains unclear how trees and forests respond to such unusual drought, particularly Southeast Asian tropical rain forests. To understand leaf ecophysiological responses of tropical rain forest trees to soil drying, a rainfall exclusion experiment was conducted on mature canopy trees of Dryobalanops aromatica Gaertn.f. (Dipterocarpaceae) for 4 months in an aseasonal tropical rain forest in Sarawak, Malaysia. The rainfall was intercepted by using a soft vinyl chloride sheet. We compared the three control and three treatment trees with respect to leaf water use at the top of the crown, including stomatal conductance (gsmax), photosynthesis (Amax), leaf water potential (predawn: Ψpre; midday: Ψmid), leaf water potential at turgor loss point (πtlp), osmotic potential at full turgor (π100) and a bulk modulus of elasticity (ε). Measurements were taken using tree-tower and canopy-crane systems. During the experiment, the treatment trees suffered drought stress without evidence of canopy dieback in comparison with the control trees; e.g., Ψpre and Ψmid decreased with soil drying. Minimum values of Ψmid in the treatment trees decreased during the experiment, and were lower than πtlp in the control trees. However, the treatment trees also decreased their πtlp by osmotic adjustment, and the values were lower than the minimum values of their Ψmid. In addition, the treatment trees maintained gs and Amax especially in the morning, though at midday, values decreased to half those of the control trees. Decreasing leaf water potential by osmotic adjustment to maintain gs and Amax under soil drying in treatment trees was considered to represent anisohydric behavior. These results suggest that D. aromatica may have high leaf adaptability to drought by regulating leaf water consumption and maintaining turgor pressure to improve its leaf

  20. Using miniature osmotic infusion pumps to maintain tritiated thymidine exposure to cells in culture

    International Nuclear Information System (INIS)

    Neely, J.E.; Hake, D.A.

    1982-01-01

    To provide a constant level of tracer doses of tritiated thymidine to cultured cells during continuous infusion, miniature osmotic infusion pumps were used to provide replacement thymidine. By determining the loss of isotope from the media during nonreplacement, the rate of constant infusion replacement to maintain thymidine levels was calculated. The replacement rates were similar for the three cell lines examined and allowed a standard osmotic pump infusion

  1. Thermalization as an invisibility cloak for fragile quantum superpositions

    Science.gov (United States)

    Hahn, Walter; Fine, Boris V.

    2017-07-01

    We propose a method for protecting fragile quantum superpositions in many-particle systems from dephasing by external classical noise. We call superpositions "fragile" if dephasing occurs particularly fast, because the noise couples very differently to the superposed states. The method consists of letting a quantum superposition evolve under the internal thermalization dynamics of the system, followed by a time-reversal manipulation known as Loschmidt echo. The thermalization dynamics makes the superposed states almost indistinguishable during most of the above procedure. We validate the method by applying it to a cluster of spins ½.

  2. Dopamine transporter imaging study in parkinsonism occurring in fragile X premutation carriers.

    Science.gov (United States)

    Ceravolo, R; Antonini, A; Volterrani, D; Rossi, C; Goldwurm, S; Di Maria, E; Kiferle, L; Bonuccelli, U; Murri, L

    2005-12-27

    The authors studied four patients with parkinsonism carrying the fragile X premutation using SPECT with ([23)I]FP-CIT. They found evidence of preserved presynaptic nigrostriatal function, suggesting that parkinsonism in the X fragile premutation might be related to postsynaptic dopaminergic changes or different neurotransmitter alterations.

  3. Mechanical properties of the collagen network in human articular cartilage as measured by osmotic stress technique

    NARCIS (Netherlands)

    Basser, P.J.; Schneiderman, R.; Bank, R.A.; Wachtel, E.; Maroudas, A.

    1998-01-01

    We have used an isotropic osmotic stress technique to assess the swelling pressures of human articular cartilage over a wide range of hydrations in order to determine from these measurements, for the first time, the tensile stress in the collagen network, P(c), as a function of hydration. Osmotic

  4. Copper oxide content dependence of crystallization behavior, glass forming ability, glass stability and fragility of lithium borate glasses

    International Nuclear Information System (INIS)

    Soliman, A.A.; Kashif, I.

    2010-01-01

    Differential thermal analysis (DTA) and X-ray diffraction (XRD) have been employed to investigate the copper oxide content dependence of the glass transition temperatures data, activation energy for the glass transition E t , glass stability GS, fragility index Fi, the glass-forming ability (GFA) and crystallization behavior of {(100-x) mol% Li 2 B 4 O 7 -x mol% CuO} glass samples, where x=0-40 mol% CuO. From the dependence of the glass transition temperature T g on the heating rate β, the fragility, F i , and the activation energy, E t , have been calculated. It is seen that F i and E t are attained their minimum values at 0 x -T g , SCL region and the GS. The GFA has been investigated on the basis of Hruby parameter K H , which is a strong indicator of GFA, and the relaxation time. Results of GFA are in good agreement with the fragility index, F i , calculations indicating that {90Li 2 B 4 O 7 .10CuO} is the best glass former. The stronger glass forming ability has decreasing the fragility index. XRD result indicates that no fully amorphous samples but a mixture of crystalline and amorphous phases are formed in the samples containing x>25 mol% CuO and below it composed of glassy phase. Increasing the CuO content above 25 mol% helps the crystallization process, and thus promotes a distinct SCL region. XRD suggests the presence of micro-crystallites of remaining residual amorphous matrix by increasing the CuO content.

  5. An osmotic model of the growing pollen tube.

    Directory of Open Access Journals (Sweden)

    Adrian E Hill

    Full Text Available Pollen tube growth is central to the sexual reproduction of plants and is a longstanding model for cellular tip growth. For rapid tip growth, cell wall deposition and hardening must balance the rate of osmotic water uptake, and this involves the control of turgor pressure. Pressure contributes directly to both the driving force for water entry and tip expansion causing thinning of wall material. Understanding tip growth requires an analysis of the coordination of these processes and their regulation. Here we develop a quantitative physiological model which includes water entry by osmosis, the incorporation of cell wall material and the spreading of that material as a film at the tip. Parameters of the model have been determined from the literature and from measurements, by light, confocal and electron microscopy, together with results from experiments made on dye entry and plasmolysis in Lilium longiflorum. The model yields values of variables such as osmotic and turgor pressure, growth rates and wall thickness. The model and its predictive capacity were tested by comparing programmed simulations with experimental observations following perturbations of the growth medium. The model explains the role of turgor pressure and its observed constancy during oscillations; the stability of wall thickness under different conditions, without which the cell would burst; and some surprising properties such as the need for restricting osmotic permeability to a constant area near the tip, which was experimentally confirmed. To achieve both constancy of pressure and wall thickness under the range of conditions observed in steady-state growth the model reveals the need for a sensor that detects the driving potential for water entry and controls the deposition rate of wall material at the tip.

  6. An Osmotic Model of the Growing Pollen Tube

    Science.gov (United States)

    Hill, Adrian E.; Shachar-Hill, Bruria; Skepper, Jeremy N.; Powell, Janet; Shachar-Hill, Yair

    2012-01-01

    Pollen tube growth is central to the sexual reproduction of plants and is a longstanding model for cellular tip growth. For rapid tip growth, cell wall deposition and hardening must balance the rate of osmotic water uptake, and this involves the control of turgor pressure. Pressure contributes directly to both the driving force for water entry and tip expansion causing thinning of wall material. Understanding tip growth requires an analysis of the coordination of these processes and their regulation. Here we develop a quantitative physiological model which includes water entry by osmosis, the incorporation of cell wall material and the spreading of that material as a film at the tip. Parameters of the model have been determined from the literature and from measurements, by light, confocal and electron microscopy, together with results from experiments made on dye entry and plasmolysis in Lilium longiflorum. The model yields values of variables such as osmotic and turgor pressure, growth rates and wall thickness. The model and its predictive capacity were tested by comparing programmed simulations with experimental observations following perturbations of the growth medium. The model explains the role of turgor pressure and its observed constancy during oscillations; the stability of wall thickness under different conditions, without which the cell would burst; and some surprising properties such as the need for restricting osmotic permeability to a constant area near the tip, which was experimentally confirmed. To achieve both constancy of pressure and wall thickness under the range of conditions observed in steady-state growth the model reveals the need for a sensor that detects the driving potential for water entry and controls the deposition rate of wall material at the tip. PMID:22615784

  7. Epilepsy in fragile-X-syndrome mimicking panayiotopoulos syndrome: Description of three patients.

    Science.gov (United States)

    Bonanni, Paolo; Casellato, Susanna; Fabbro, Franco; Negrin, Susanna

    2017-10-01

    Fragile-X-syndrome is the most common cause of inherited intellectual disability. Epilepsy is reported to occur in 10-20% of individuals with Fragile-X-syndrome. A frequent seizure/electroencephalogram (EEG) pattern resembles that of benign rolandic epilepsy. We describe the clinical features, EEG findings and evolution in three patients affected by Fragile-X-syndrome and epilepsy mimicking Panayiotopoulos syndrome. Age at seizure onset was between 4 and about 7 years. Seizures pattern comprised a constellation of autonomic symptoms with unilateral deviation of the eyes and ictal syncope. Duration of the seizures could be brief or lengthy. Interictal EEGs revealed functional multifocal abnormalities. The evolution was benign in all patients with seizures remission before the age of 14. This observation expands the spectrum of benign epileptic phenotypes present in Fragile-X-syndrome and may be quite helpful in guiding anticonvulsant management and counseling families as to expectations regarding seizure remission. © 2017 Wiley Periodicals, Inc.

  8. Vocal Fold Epithelial Response to Luminal Osmotic Perturbation

    Science.gov (United States)

    Sivasankar, Mahalakshmi; Fisher, Kimberly V.

    2007-01-01

    Purpose: Dry-air challenges increase the osmolarity of fluid lining the luminal surface of the proximal airway. The homeostasis of surface fluid is thought to be essential for voice production and laryngeal defense. Therefore, the authors hypothesized that viable vocal fold epithelium would generate a water flux to reduce an osmotic challenge (150…

  9. The Effect of Iron Deficiency on Osmotic Sensitivity of Red Blood Cells from Neonatal Rats and Their Mothers.

    Science.gov (United States)

    Al-Hashimi, L Mossa; Gambling, Lorraine; McArdle, H J

    2015-12-01

    Iron deficiency during pregnancy has many effects on both the mother and her developing foetus. These can be both short and long term. One effect is an alteration in fatty acid metabolism and we hypothesised that these changes may result in alterations in membrane function and structure. In order to test this hypothesis, we measured osmotic sensitivity in red blood cells isolated from neonates and their mothers at different times following birth. We fed female rats control or iron-deficient diets for 4 weeks prior to mating and kept them on the same diet until term. At that time, we returned one group of deficient dams to the control diet. The others were kept on the same diet. We showed that iron deficiency results in a decrease in osmotic sensitivity in the mothers but not in their neonates. Returning the dams to the control diet resulted in a return of their red cell osmotic sensitivity to control levels. In the neonates, there was no recovery in haematocrit or in any other parameter, though they did not get any worse, in contrast to the pups being suckled by deficient mothers. The data show two things. The first is that following birth, the mother restores her own iron stores at the expense of the pups, and secondly, there are differences in properties and sensitivities between red cells from mothers and their neonates. This latter observation cannot be explained by differences in the membrane fatty acid profiles, which were not significantly different.

  10. Arabidopsis decuple mutant reveals the importance of SnRK2 kinases in osmotic stress responses in vivo

    KAUST Repository

    Fujii, Hiroaki; Verslues, Paul E.; Zhu, Jian-Kang

    2011-01-01

    Osmotic stress associated with drought or salinity is a major factor that limits plant productivity. Protein kinases in the SNF1-related protein kinase 2 (SnRK2) family are activated by osmotic stress, suggesting that the kinases are involved

  11. Characterization of Macrophomina phaseolina isolates by their response to different osmotic potentials and AFLP

    Directory of Open Access Journals (Sweden)

    Bárbara J. Gutiérrez Cedeño

    2014-01-01

    Full Text Available Charcoal rot of Phaseolus vulgaris is caused by the fungus Macrophomina phaseolina, the disease is associated with high temperature and water stress. The objective of this study was to characterize isolates of M. phaseolina by their response to different osmotic potentials and AFLP. The growth of 11 isolates was determined on potato dextrose agar at 48 and 72 h in a gradient of osmotic potential induced using NaCl as well as their effects on germination of sclerotia. Three water groups were statistically different indicating differential response to osmotic potential and all sclerotia grown under these conditions, germinated between 24 and 48h. There were groups of isolates that were tolerant to water stress induced. The AFLP genotyping allowed the formation of five genetic groups, showing a wide genetic variability. Of the nine starters CTA-AT showed a high degree of confidence in the identification of genotypes of M. phaseolina and CAA-AC had the lowest discriminatory power. These results show that M. phaseolina isolates responded differently to osmotic potential and are genetically different between them. Although there was a clear correspondence of genetic groups to water groups; these responses are important features in the search for alternative management in black bean pathosystem. Keywords: molecular marker, M. phaseolina, water deficit

  12. Topology and shape optimization of induced-charge electro-osmotic micropumps

    DEFF Research Database (Denmark)

    Gregersen, Misha Marie; Okkels, Fridolin; Bazant, M. Z.

    2009-01-01

    For a dielectric solid surrounded by an electrolyte and positioned inside an externally biased parallel-plate capacitor, we study numerically how the resulting induced-charge electro-osmotic (ICEO) flow depends on the topology and shape of the dielectric solid. In particular, we extend existing...... conventional electrokinetic models with an artificial design field to describe the transition from the liquid electrolyte to the solid dielectric. Using this design field, we have succeeded in applying the method of topology optimization to find system geometries with non-trivial topologies that maximize...... the net induced electro-osmotic flow rate through the electrolytic capacitor in the direction parallel to the capacitor plates. Once found, the performance of the topology-optimized geometries has been validated by transferring them to conventional electrokinetic models not relying on the artificial...

  13. Osmotically driven membrane process for the management of urban runoff in coastal regions

    KAUST Repository

    Li, Zhenyu

    2014-01-01

    An osmotic detention pond was proposed for the management of urban runoff in coastal regions. Forward osmosis was employed as a bridge to utilize natural osmotic energy from seawater for concentrating and reusing urban runoff water, and as a barrier to reject runoff-derived contaminants. The process was demonstrated by a lab scale testing using synthetic urban runoff (as the feed solution) and synthetic seawater (as the draw solution). The submerged forward osmosis process was conducted under neutral, acidic and natural organic matter fouling condition, respectively. Forward osmosis flux decline was mainly attributed to the dilution of seawater during a semi-batch process in lab scale testing. However, it is possible to minimize flux decrease by maintaining a constant salinity at the draw solution side. Various changes in urban runoff water quality, including acidic conditions (acid rain) and natural organic matter presence, did not show significant effects on the rejection of trace metals and phosphorus, but influenced salt leakage and the rejection of nitrate and total nitrogen. Rejection of trace metals varied from 98% to 100%, phosphorus varied from 97% to 100, nitrate varied from 52% to 94% and total nitrogen varied from 65% to 85% under different feed water conditions. The work described in this study contributes to an integrated system of urban runoff management, seawater desalination and possible power generation in coastal regions to achieve a sustainable solution to the water-energy nexus. © 2013 Elsevier Ltd.

  14. Osmotically driven membrane process for the management of urban runoff in coastal regions.

    Science.gov (United States)

    Li, Zhenyu; Valladares Linares, Rodrigo; Abu-Ghdaib, Muhannad; Zhan, Tong; Yangali-Quintanilla, Victor; Amy, Gary

    2014-01-01

    An osmotic detention pond was proposed for the management of urban runoff in coastal regions. Forward osmosis was employed as a bridge to utilize natural osmotic energy from seawater for concentrating and reusing urban runoff water, and as a barrier to reject runoff-derived contaminants. The process was demonstrated by a lab scale testing using synthetic urban runoff (as the feed solution) and synthetic seawater (as the draw solution). The submerged forward osmosis process was conducted under neutral, acidic and natural organic matter fouling condition, respectively. Forward osmosis flux decline was mainly attributed to the dilution of seawater during a semi-batch process in lab scale testing. However, it is possible to minimize flux decrease by maintaining a constant salinity at the draw solution side. Various changes in urban runoff water quality, including acidic conditions (acid rain) and natural organic matter presence, did not show significant effects on the rejection of trace metals and phosphorus, but influenced salt leakage and the rejection of nitrate and total nitrogen. Rejection of trace metals varied from 98% to 100%, phosphorus varied from 97% to 100, nitrate varied from 52% to 94% and total nitrogen varied from 65% to 85% under different feed water conditions. The work described in this study contributes to an integrated system of urban runoff management, seawater desalination and possible power generation in coastal regions to achieve a sustainable solution to the water-energy nexus. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Multiple Behavior Phenotypes of the Fragile-X Syndrome Mouse Model Respond to Chronic Inhibition of Phosphodiesterase-4D (PDE4D).

    Science.gov (United States)

    Gurney, Mark E; Cogram, Patricia; Deacon, Robert M; Rex, Christopher; Tranfaglia, Michael

    2017-11-07

    Fragile-X syndrome (FXS) patients display intellectual disability and autism spectrum disorder due to silencing of the X-linked, fragile-X mental retardation-1 (FMR1) gene. Dysregulation of cAMP metabolism is a consistent finding in patients and in the mouse and fly FXS models. We therefore explored if BPN14770, a prototypic phosphodiesterase-4D negative allosteric modulator (PDE4D-NAM) in early human clinical trials, might provide therapeutic benefit in the mouse FXS model. Daily treatment of adult male fmr1 C57Bl6 knock-out mice with BPN14770 for 14 days reduced hyperarousal, improved social interaction, and improved natural behaviors such as nesting and marble burying as well as dendritic spine morphology. There was no decrement in behavioral scores in control C57Bl6 treated with BPN14770. The behavioral benefit of BPN14770 persisted two weeks after washout of the drug. Thus, BPN14770 may be useful for the treatment of fragile-X syndrome and other disorders with decreased cAMP signaling.

  16. Benchtop-magnetic resonance imaging (BT-MRI) characterization of push-pull osmotic controlled release systems.

    Science.gov (United States)

    Malaterre, Vincent; Metz, Hendrik; Ogorka, Joerg; Gurny, Robert; Loggia, Nicoletta; Mäder, Karsten

    2009-01-05

    The mechanism of drug release from push-pull osmotic systems (PPOS) has been investigated by Magnetic Resonance Imaging (MRI) using a new benchtop apparatus. The signal intensity profiles of both PPOS layers were monitored non-invasively over time to characterize the hydration and swelling kinetics. The drug release performance was well-correlated to the hydration kinetics. The results show that (i) hydration and swelling critically depend on the tablet core composition, (ii) high osmotic pressure developed by the push layer may lead to bypassing the drug layer and incomplete drug release and (iii) the hydration of both the drug and the push layers needs to be properly balanced to efficiently deliver the drug. MRI is therefore a powerful tool to get insights on the drug delivery mechanism of push-pull osmotic systems, which enable a more efficient optimization of such formulations.

  17. Biochemical degradation and physical migration of polyphenolic compounds in osmotic dehydrated blueberries with pulsed electric field and thermal pretreatments.

    Science.gov (United States)

    Yu, Yuanshan; Jin, Tony Z; Fan, Xuetong; Wu, Jijun

    2018-01-15

    Fresh blueberries were pretreated by pulsed electric fields (PEF) or thermal pretreatment and then were subject to osmotic dehydration. The changes in contents of anthocyanins, predominantly phenolic acids and flavonols, total phenolics, polyphenol oxidase (PPO) activity and antioxidant activity in the blueberry samples during pretreatment and osmotic dehydration were investigated. Biochemical degradation and physical migration of these nutritive compounds from fruits to osmotic solutions were observed during the pretreatments and osmotic dehydration. PEF pretreated samples had the least degradation loss but the most migration loss of these compounds compared to thermally pretreated and control samples. Higher rates of water loss and solid gain during osmotic dehydration were also obtained by PEF pretreatment, reducing the dehydration time from 130 to 48h. PEF pretreated and dehydrated fruits showed superior appearance to thermally pretreated and control samples. Therefore, PEF pretreatment is a preferred technology that balances nutritive quality, appearance, and dehydration rate. Published by Elsevier Ltd.

  18. Comparison of osmotic swelling influences on meniscal fibrocartilage and articular cartilage tissue mechanics in compression and shear.

    Science.gov (United States)

    Nguyen, An M; Levenston, Marc E

    2012-01-01

    Although the contribution of the circumferential collagen bundles to the anisotropic tensile stiffness of meniscal tissue has been well described, the implications of interactions between tissue components for other mechanical properties have not been as widely examined. This study compared the effects of the proteoglycan-associated osmotic swelling stress on meniscal fibrocartilage and articular cartilage (AC) mechanics by manipulating the osmotic environment and tissue compressive offset. Cylindrical samples were obtained from the menisci and AC of bovine stifles, equilibrated in phosphate-buffered saline solutions ranging from 0.1× to 10×, and tested in oscillatory torsional shear and unconfined compression. Biochemical analysis indicated that treatments and testing did not substantially alter tissue composition. Mechanical testing revealed tissue-specific responses to both increasing compressive offset and decreasing bath salinity. Most notably, reduced salinity dramatically increased the shear modulus of both axially and circumferentially oriented meniscal tissue explants to a much greater extent than for cartilage samples. Combined with previous studies, these findings suggest that meniscal proteoglycans have a distinct structural role, stabilizing, and stiffening the matrix surrounding the primary circumferential collagen bundles. Copyright © 2011 Orthopaedic Research Society.

  19. Mathematical modelling of the osmotic dehydration of cherry tomato (Lycopersicon esculentum var. cerasiforme

    Directory of Open Access Journals (Sweden)

    AZOUBEL Patricia Moreira

    2000-01-01

    Full Text Available Osmotic dehydration of cherry tomato as influenced by osmotic agent (sodium chloride and a mixed sodium chloride and sucrose solutions and solution concentration (10 and 25% w/w at room temperature (25°C was studied. Kinetics of water loss and solids uptake were determined by a two parameter model, based on Fick's second law and applied to spherical geometry. The water apparent diffusivity coefficients obtained ranged from 2.17x10-10 to 11.69x10-10 m²/s.

  20. A nonsense mutation in FMR1 causing fragile X syndrome

    DEFF Research Database (Denmark)

    Grønskov, Karen; Brøndum-Nielsen, Karen; Dedic, Alma

    2011-01-01

    Fragile X syndrome is a common cause of inherited intellectual disability. It is caused by lack of the FMR1 gene product FMRP. The most frequent cause is the expansion of a CGG repeat located in the 5'UTR of FMR1. Alleles with 200 or more repeats become hypermethylated and transcriptionally silent....... Only few patients with intragenic point mutations in FMR1 have been reported and, currently, routine analysis of patients referred for fragile X syndrome includes solely analysis for repeat expansion and methylation status. We identified a substitution in exon 2 of FMR1, c.80C>A, causing a nonsense...... mutation p.Ser27X, in a patient with classical clinical symptoms of fragile X syndrome. The mother who carried the mutation in heterozygous form presented with mild intellectual impairment. We conclude that further studies including western blot and DNA sequence analysis of the FMR1 gene should...

  1. Seismic margins review of nuclear power plants: Fragility aspects

    International Nuclear Information System (INIS)

    Ravindra, M.K.; Hardy, G.S.; Hashimoto, P.S.

    1987-01-01

    The fragility analysis is utilised in the seismic margin review in initial screening of certain components in the plant based on their generically high seismic capacities. A detailed walkdown of the plant is conducted to confirm that the initial screening is valid i.e., the generically high seismic capacity components do not possess any potential weaknesses (e.g., inadequate bracing, inadequate anchorage and potential systems interaction). For the components that are screened in, their seismic capacities are evaluated using either a probabilistic analysis of a deterministic evaluation. Based on a system analysis, the Boolean expressions for critical accident sequences are derived. These Boolean expressions are quantified using the component fragilities and nonseismic unavailabilities of components. The final product is the High Confidence Low Probability of Failure (HCLPF) capacity of the plant and the identification of potential seismic vulnerabilities in the plant. The objective of the paper is to describe the application of fragility analysis procedures in the seismic margin review of Maine Yankee and to document the insights obtained in this trial plant review. (orig./HP)

  2. Clinical assessment tools identify functional deficits in fragility fracture patients

    Directory of Open Access Journals (Sweden)

    Ames TD

    2016-05-01

    Full Text Available Tyler D Ames,1 Corinne E Wee,1 Khoi M Le,1 Tiffany L Wang,1 Julie Y Bishop,2 Laura S Phieffer,2 Carmen E Quatman2 1The Ohio State University College of Medicine, 2Department of Orthopaedics, The Ohio State University Wexner Medical Center, Columbus, OH, USA Purpose: To identify inexpensive, noninvasive, portable, clinical assessment tools that can be used to assess functional performance measures that may put older patients at risk for falls such as balance, handgrip strength, and lumbopelvic control.Patients and methods: Twenty fragility fracture patients and 21 healthy control subjects were evaluated using clinical assessment tools (Nintendo Wii Balance Board [WBB], a handheld dynamometer, and an application for the Apple iPod Touch, the Level Belt that measure functional performance during activity of daily living tasks. The main outcome measurements were balance (WBB, handgrip strength (handheld dynamometer, and lumbopelvic control (iPod Touch Level Belt, which were compared between fragility fracture patients and healthy controls.Results: Fragility fracture patients had lower scores on the vertical component of the WBB Torso Twist task (P=0.042 and greater medial–lateral lumbopelvic sway during a 40 m walk (P=0.026 when compared to healthy controls. Unexpectedly, the fracture patients had significantly higher scores on the left leg (P=0.020 and total components (P=0.010 of the WBB Single Leg Stand task as well as less faults during the left Single Leg Stand task (P=0.003.Conclusion: The clinical assessment tools utilized in this study are relatively inexpensive and portable tools of performance measures capable of detecting differences in postural sway between fragility fracture patients and controls. Keywords: fall risk, geriatric fracture, Nintendo Wii Balance Board, Level Belt, fragility fracture

  3. Fragility analysis methodology for degraded structures and passive components in nuclear power plantsIllustrated using a condensate storage tank

    International Nuclear Information System (INIS)

    Nie, Jinsuo; Braverman, Joseph; Hofmayer, Charles; Choun, Young Sun; Kim, Min Kyu; Choi, In Kil

    2010-06-01

    This report describes the seismic fragility capacity for a condensate storage tank with various degradation scenarios. The conservative deterministic failure margin method has been utilized for the undegraded case and has been modified to accommodate the degraded cases. A total of five seismic fragility analysis cases have been described: (1) undegraded case, (2) degraded stainless tank shell, (3) degraded anchor bolts, (4) anchorage concrete cracking, and (5) a perfect correlation of the three degradation scenarios. Insights from these fragility analyses are also presented. An overview of the methods for seismic fragility analysis and generic approaches to incorporate time-dependent degradation models into a fragility analysis is presented. Fundamental concepts of seismic fragility analysis are summarized to facilitate discussions in later sections. The seismic fragility analysis of the undegraded CST, which is assumed to have all of its components in design condition, is described. The subject CST was located in an operating Korean NPP. The baseline fragility capacity of the CST is calculated and the basic procedure of seismic fragility analysis is established. This report presents the results and insights of the seismic fragility analysis of the CST under various postulated degradation scenarios

  4. Ocular Motor Indicators of Executive Dysfunction in Fragile X and Turner Syndromes

    Science.gov (United States)

    Lasker, Adrian G.; Mazzocco, Michele M. M.; Zee, David S.

    2007-01-01

    Fragile X and Turner syndromes are two X-chromosome-related disorders associated with executive function and visual spatial deficits. In the present study, we used ocular motor paradigms to examine evidence that disruption to different neurological pathways underlies these deficits. We tested 17 females with fragile X, 19 females with Turner…

  5. Visual Pathway Deficit in Female Fragile X Premutation Carriers: A Potential Endophenotype

    Science.gov (United States)

    Keri, Szabolcs; Benedek, Gyorgy

    2009-01-01

    Previous studies indicated impaired magnocellular (M) and relatively spared parvocellular (P) visual pathway functioning in patients with fragile X syndrome. In this study, we assessed M and P pathways in 22 female fragile X premutation carriers with normal intelligence and in 20 healthy non-carrier controls. Testing procedure included visual…

  6. Regulation of Aquaporin Z osmotic permeability in ABA tri-block copolymer

    Directory of Open Access Journals (Sweden)

    Wenyuan Xie

    2015-08-01

    Full Text Available Aquaporins are transmembrane water channel proteins present in biological plasma membranes that aid in biological water filtration processes by transporting water molecules through at high speeds, while selectively blocking out other kinds of solutes. Aquaporin Z incorporated biomimetic membranes are envisaged to overcome the problem of high pressure needed, and holds great potential for use in water purification processes, giving high flux while keeping energy consumption low. The functionality of aquaporin Z in terms of osmotic permeability might be regulated by factors such as pH, temperature, crosslinking and hydrophobic thickness of the reconstituted bilayers. Hence, we reconstituted aquaporin Z into vesicles that are made from a series of amphiphilic block copolymers PMOXA-PDMS-PMOXAs with various hydrophobic molecular weights. The osmotic permeability of aquaporin Z in these vesicles was determined through a stopped-flow spectroscopy. In addition, the temperature and pH value of the vesicle solutions were adjusted within wide ranges to investigate the regulation of osmotic permeability of aquaporin Z through external conditions. Our results show that aquaporin Z permeability was enhanced by hydrophobic mismatch. In addition, the water filtration mechanism of aquaporin Z is significantly affected by the concentration of H+ and OH- ions.

  7. Design and development of controlled porosity osmotic tablet of diltiazem hydrochloride

    Directory of Open Access Journals (Sweden)

    Sadhana R Shahi

    2012-01-01

    Full Text Available The present work aims towards the design and development of extended release formulation of freely water-soluble drug diltiazem hydrochloride (DLTZ based on osmotic technology by using controlled porosity approach. DLTZ is an ideal candidate for a zero-order drug delivery system because it is freely water-soluble and has a short half-life (2-3 h. Sodium chloride (Osmogen was added to the core tablet to alter the solubility of DLTZ in an aqueous medium. Cellulose acetate (CA and sorbitol were used as semipermeable membrane and pore former, respectively. The effect of different formulation variables namely concentration of osmogen in the core tablet, % pore former, % weight gain, pH of the dissolution medium and agitation intensity on the in vitro release was studied. DLTZ release was directly proportional to % pore former and inversely proportional to % weight gain. The optimized formulation (F8 delivered DLTZ independent of pH and agitation intensity for 12 h at the upper level concentration of % pore former (25% w/w and middle level concentration of % weight gain (6% w/w. The comparative study of elementary osmotic pump (EOP and controlled porosity osmotic pump revealed that it superior than conventional EOP and also easier and cost effective to formulate.

  8. Electro-osmotic flow through nanopores in thin and ultrathin membranes

    Science.gov (United States)

    Melnikov, Dmitriy V.; Hulings, Zachery K.; Gracheva, Maria E.

    2017-06-01

    We theoretically study how the electro-osmotic fluid velocity in a charged cylindrical nanopore in a thin solid state membrane depends on the pore's geometry, membrane charge, and electrolyte concentration. We find that when the pore's length is comparable to its diameter, the velocity profile develops a concave shape with a minimum along the pore axis unlike the situation in very long nanopores with a maximum velocity along the central pore axis. This effect is attributed to the induced pressure along the nanopore axis due to the fluid flow expansion and contraction near the exit or entrance to the pore and to the reduction of electric field inside the nanopore. The induced pressure is maximal when the pore's length is about equal to its diameter while decreasing for both longer and shorter nanopores. A model for the fluid velocity incorporating these effects is developed and shown to be in a good agreement with numerically computed results.

  9. Method of osmotic energy harvesting using responsive compounds and molecules

    KAUST Repository

    Hu, Xiao; Cai, Yufeng; Lai, Zhiping; Zhong, Yujiang

    2017-01-01

    The present invention discloses and claims a more efficient and economical method and system for osmotic energy production and capture using responsive compounds and molecules. The present invention is an energy harvest system enabled by stimuli

  10. Modelling the coupled chemico-osmotic and advective-diffusive transport of nitrate salts in the Callovo-Oxfordian clay

    International Nuclear Information System (INIS)

    Baechler, S.; Croise, J.; Altmann, S.

    2010-01-01

    Document available in extended abstract form only. Fine-grained saturated porous materials can act as a semi-permeable osmotic membrane when exposed to a solute concentration gradient. The ions diffusion is hindered while water movement towards higher concentrations takes place in the semi-permeable membrane. The capacity of the fine-grained porous material to act as a semi permeable osmotic membrane is referred to as the osmotic efficiency (its value is 1 when the membranes is ideal, less than 1 when the membrane is leaky, allowing diffusion). The efficiency to retain ions in solution is dependent on the thickness of the diffuse double layer which itself depends on the solution concentration in the membrane. Clay rich formations have been shown to act as non-ideal semi-permeable membrane. Andra is investigating the Callovo-Oxfordian clay as a host rock for intermediate-level to high-level radioactive waste. In this context, it has been feared that osmotic water flows generated by the release of sodium nitrate salt in high concentrations, out of intermediate radioactive bituminous waste, could induce important over-pressures. The latest would eventually lead to fracturing of the host rock around the waste disposal drifts. The purpose of the present study was to develop a simulation code with the capacity to assess the potential impact of osmosis on: the re-saturation of the waste disposal drifts, the pressure evolution and the solute transport in and around a waste disposal drift. A chemo-osmotic coupled flow and transport model was implemented using the FlexPDE-finite element library. Our model is based on the chemo-osmotic formulation developed by Bader and Kooi, 2005. The model has been extended to highly concentrated solutions based on Pitzer's equation. In order to assess the impact of osmotic flow on the re-saturation time, the model was also designed to allow unsaturated flow modelling. The model configuration consists of an initially unsaturated 2D

  11. Abscisic acid regulates root growth under osmotic stress conditions via an interacting hormonal network with cytokinin, ethylene and auxin.

    Science.gov (United States)

    Rowe, James H; Topping, Jennifer F; Liu, Junli; Lindsey, Keith

    2016-07-01

    Understanding the mechanisms regulating root development under drought conditions is an important question for plant biology and world agriculture. We examine the effect of osmotic stress on abscisic acid (ABA), cytokinin and ethylene responses and how they mediate auxin transport, distribution and root growth through effects on PIN proteins. We integrate experimental data to construct hormonal crosstalk networks to formulate a systems view of root growth regulation by multiple hormones. Experimental analysis shows: that ABA-dependent and ABA-independent stress responses increase under osmotic stress, but cytokinin responses are only slightly reduced; inhibition of root growth under osmotic stress does not require ethylene signalling, but auxin can rescue root growth and meristem size; osmotic stress modulates auxin transporter levels and localization, reducing root auxin concentrations; PIN1 levels are reduced under stress in an ABA-dependent manner, overriding ethylene effects; and the interplay among ABA, ethylene, cytokinin and auxin is tissue-specific, as evidenced by differential responses of PIN1 and PIN2 to osmotic stress. Combining experimental analysis with network construction reveals that ABA regulates root growth under osmotic stress conditions via an interacting hormonal network with cytokinin, ethylene and auxin. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  12. Modeling and computational simulation of the osmotic evaporation process

    Directory of Open Access Journals (Sweden)

    Freddy Forero Longas

    2016-09-01

    Conclusions: It was found that for the conditions studied the Knudsen diffusion model is most suitable to describe the transfer of water vapor through the hydrophobic membrane. Simulations developed adequately describe the process of osmotic evaporation, becoming a tool for faster economic development of this technology.

  13. Optimization of the Energy Output of Osmotic Power Plants

    Directory of Open Access Journals (Sweden)

    Florian Dinger

    2013-01-01

    Full Text Available On the way to a completely renewable energy supply, additional alternatives to hydroelectric, wind, and solar power have to be investigated. Osmotic power is such an alternative with a theoretical global annual potential of up to 14400 TWh (70% of the global electricity consumption of 2008 per year. It utilizes the phenomenon that upon the mixing of fresh water and oceanic salt water (e.g., at a river mouth, around 2.88 MJ of energy per 1 m3 of fresh water is released. Here, we describe a new approach to derive operational parameter settings for osmotic power plants using a pressure exchanger for optimal performance, either with respect to maximum generated power or maximum extracted energy. Up to now, only power optimization is discussed in the literature, but when considering the fresh water supply as a limiting factor, the energy optimization appears as the challenging task.

  14. The physics of osmotic pressure

    Science.gov (United States)

    Bowler, M. G.

    2017-09-01

    Osmosis drives the development of a pressure difference of many atmospheres between a dilute solution and pure solvent with which it is in contact through a semi-permeable membrane. The educational importance of this paper is that it presents a novel treatment in terms of fluid mechanics that is quantitative and exact. It is also simple and intuitive, showing vividly how osmotic pressures are generated and maintained in equilibrium, driven by differential solvent pressures. The present rigorous analysis using the virial theorem seems unknown and can be easily understood—and taught—at various different levels. It should be valuable to undergraduates, graduate students and indeed to the general physicist.

  15. Water and sucrose diffusion coefficients during osmotic dehydration of sapodilla (Achras zapota L.

    Directory of Open Access Journals (Sweden)

    Lívia Muritiba Pereira de Lima Coimbra

    Full Text Available ABSTRACT: Sapodilla is an original fruit from Central America that is well adapted in all regions of the Brazilian territory. Despite its wide adaptation and acceptance in fruit markets, it is rare to find it outside tropical regions, partially because of its high perishability. The development of alternative, simple, and inexpensive methods to extend the conservation and marketing of these fruits is important, and osmotic dehydration is one of these methods. The main objective of this study was to determine the water and sucrose diffusion coefficients during the osmotic dehydration of sapodilla. This process was performed in short duration (up to 6h to evaluate detailed information on water loss and solids gain kinetics at the beginning of the process and in long duration (up to 60h to determine the equilibrium concentrations in sapodilla. The immersion time had greater influence on the water and sucrose diffusion coefficients (P<0.05; the maximum water loss (WL and solute gain (SG occurred in the osmotic solution at the highest concentration. Water and sucrose diffusion coefficients ranged from 0.00 x 10-10 m2/s to 1.858 x 10-10 m2/s, and from 0.00 x 10-10to 2.304 x 10-10 m2/s, respectively. Thus, understanding the WL and SG kinetics during the process of sapodilla osmotic dehydration could significantly contribute to new alternatives of preservation and commercialization of this fruit.

  16. Multiple Drug Treatments That Increase cAMP Signaling Restore Long-Term Memory and Aberrant Signaling in Fragile X Syndrome Models

    Science.gov (United States)

    Choi, Catherine H.; Schoenfeld, Brian P.; Bell, Aaron J.; Hinchey, Joseph; Rosenfelt, Cory; Gertner, Michael J.; Campbell, Sean R.; Emerson, Danielle; Hinchey, Paul; Kollaros, Maria; Ferrick, Neal J.; Chambers, Daniel B.; Langer, Steven; Sust, Steven; Malik, Aatika; Terlizzi, Allison M.; Liebelt, David A.; Ferreiro, David; Sharma, Ali; Koenigsberg, Eric; Choi, Richard J.; Louneva, Natalia; Arnold, Steven E.; Featherstone, Robert E.; Siegel, Steven J.; Zukin, R. Suzanne; McDonald, Thomas V.; Bolduc, Francois V.; Jongens, Thomas A.; McBride, Sean M. J.

    2016-01-01

    Fragile X is the most common monogenic disorder associated with intellectual disability (ID) and autism spectrum disorders (ASD). Additionally, many patients are afflicted with executive dysfunction, ADHD, seizure disorder and sleep disturbances. Fragile X is caused by loss of FMRP expression, which is encoded by the FMR1 gene. Both the fly and mouse models of fragile X are also based on having no functional protein expression of their respective FMR1 homologs. The fly model displays well defined cognitive impairments and structural brain defects and the mouse model, although having subtle behavioral defects, has robust electrophysiological phenotypes and provides a tool to do extensive biochemical analysis of select brain regions. Decreased cAMP signaling has been observed in samples from the fly and mouse models of fragile X as well as in samples derived from human patients. Indeed, we have previously demonstrated that strategies that increase cAMP signaling can rescue short term memory in the fly model and restore DHPG induced mGluR mediated long term depression (LTD) in the hippocampus to proper levels in the mouse model (McBride et al., 2005; Choi et al., 2011, 2015). Here, we demonstrate that the same three strategies used previously with the potential to be used clinically, lithium treatment, PDE-4 inhibitor treatment or mGluR antagonist treatment can rescue long term memory in the fly model and alter the cAMP signaling pathway in the hippocampus of the mouse model. PMID:27445731

  17. Long-term morphine delivery via slow release morphine pellets or osmotic pumps: Plasma concentration, analgesia, and naloxone-precipitated withdrawal.

    Science.gov (United States)

    McLane, Virginia D; Bergquist, Ivy; Cormier, James; Barlow, Deborah J; Houseknecht, Karen L; Bilsky, Edward J; Cao, Ling

    2017-09-15

    Slow-release morphine sulfate pellets and osmotic pumps are common routes of chronic morphine delivery in mouse models, but direct comparisons of these drug delivery systems are lacking. In this study, we assessed the efficacy of slow-release pellets versus osmotic pumps in delivering morphine to adult mice. Male C57BL/6NCr mice (8weeksold) were implanted subcutaneously with slow-release pellets (25mg morphine sulfate) or osmotic pumps (64mg/mL, 1.0μL/h). Plasma morphine concentrations were quantified via LC-MS/MS, analgesic efficacy was determined by tail flick assay, and dependence was assessed with naloxone-precipitated withdrawal behaviors (jumping) and physiological effects (excretion, weight loss). Morphine pellets delivered significantly higher plasma drug concentrations compared to osmotic pumps, which were limited by the solubility of the morphine sulfate and pump volume/flow rate. Within 96h post-implantation, plasma morphine concentrations were indistinguishable in pellet vs. pump-treated samples. While osmotic pump did not have an antinociceptive effect in the tail flick assay, pumps and pellets induced comparable dependence symptoms (naloxone-precipitated jumping behavior) from 24-72h post-implantation. In this study, we compared slow-release morphine pellets to osmotic minipumps for morphine delivery in mice. We found that osmotic pumps and subcutaneous morphine sulfate pellets yielded significantly different pharmacokinetics over a 7-day period, and as a result significantly different antinociceptive efficacy. Nonetheless, both delivery methods induced dependence as measured by naloxone-precipitated withdrawal. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Ionic and osmotic relations in quinoa (Chenopodium quinoa Willd.) plants grown at various salinity levels.

    Science.gov (United States)

    Hariadi, Yuda; Marandon, Karl; Tian, Yu; Jacobsen, Sven-Erik; Shabala, Sergey

    2011-01-01

    Ionic and osmotic relations in quinoa (Chenopodium quinoa Willd.) were studied by exposing plants to six salinity levels (0-500 mM NaCl range) for 70 d. Salt stress was administered either by pre-mixing of the calculated amount of NaCl with the potting mix before seeds were planted or by the gradual increase of NaCl levels in the irrigation water. For both methods, the optimal plant growth and biomass was achieved between 100 mM and 200 mM NaCl, suggesting that quinoa possess a very efficient system to adjust osmotically for abrupt increases in NaCl stress. Up to 95% of osmotic adjustment in old leaves and between 80% and 85% of osmotic adjustment in young leaves was achieved by means of accumulation of inorganic ions (Na(+), K(+), and Cl(-)) at these NaCl levels, whilst the contribution of organic osmolytes was very limited. Consistently higher K(+) and lower Na(+) levels were found in young, as compared with old leaves, for all salinity treatments. The shoot sap K(+) progressively increased with increased salinity in old leaves; this is interpreted as evidence for the important role of free K(+) in leaf osmotic adjustment under saline conditions. A 5-fold increase in salinity level (from 100 mM to 500 mM) resulted in only a 50% increase in the sap Na(+) content, suggesting either a very strict control of xylem Na(+) loading or an efficient Na(+) removal from leaves. A very strong correlation between NaCl-induced K(+) and H(+) fluxes was observed in quinoa root, suggesting that a rapid NaCl-induced activation of H(+)-ATPase is needed to restore otherwise depolarized membrane potential and prevent further K(+) leak from the cytosol. Taken together, this work emphasizes the role of inorganic ions for osmotic adjustment in halophytes and calls for more in-depth studies of the mechanisms of vacuolar Na(+) sequestration, control of Na(+) and K(+) xylem loading, and their transport to the shoot.

  19. Hydro-osmotic Instabilities in Active Membrane Tubes

    Science.gov (United States)

    Al-Izzi, Sami C.; Rowlands, George; Sens, Pierre; Turner, Matthew S.

    2018-03-01

    We study a membrane tube with unidirectional ion pumps driving an osmotic pressure difference. A pressure-driven peristaltic instability is identified, qualitatively distinct from similar tension-driven Rayleigh-type instabilities on membrane tubes. We discuss how this instability could be related to the function and biogenesis of membrane bound organelles, in particular, the contractile vacuole complex. The unusually long natural wavelength of this instability is in agreement with that observed in cells.

  20. The effects of pollutants on osmotic and ionic regulation of herring (Clupea harengus L. ) embryos and larvae

    Energy Technology Data Exchange (ETDEWEB)

    Ramsay, N.C. (Aberdeen Univ. (United Kingdom))

    1991-01-01

    This thesis looks at how osmoregulatory processes function during early ontogeny of herring (Clupea harengus L.) and how these can be affected by pollutants. First, during embryo osmoregulatory ontogeny, two distinct stages occur. Until the completion of epiboly and closure of the yolk plug, the embryo must rely wholly on passive osmoregulation. From epiboly to hatching, the embryo is able to regulate its osmolality and increases its water content through a drinking mechanism similar to that of the adult fish. Increased water content is paralleled by increased levels of solutes. The protein level thereafter decreases with subsequent increased ninhydrin positive substances. Excess salts are excreted through cells thought to be classical chloride cells. During the [open quotes]active[close quotes] osmoregulatory stage, the embryo has developed true osmotic homeostasis, providing continuity until the development of gills, skin, gut, kidney of the adult. Second, exposing embryos and larvae to a number of different pollutants affected parameters important for osmotic and ionic homeostasis. The most consistent response is an increased whole body electrolyte content and decreased water content, resulting in elevated osmolality. Exposure to drilling muds containing high levels of petrogenic components causes water loss from the larvae associated with a decreased drinking rate. Subsequent exposure to individual oil constituents at sublethal levels cause changes resulting in higher whole body electrolyte concentrations. In larvae exposed in vivo to metal levels below the Environmental Quality Standard, changes occurred in epithelial permeability. Effects on electrolyte concentrations also occurred in embryos but the mechanism was unclear. The mixture of heavy metals exposed in vitro resulted in a lower concentration required to cause a 50% reduction in whole body homogenate Na[sup +]K[sup +]-ATPase activity than for any individual metal.

  1. Development and evaluation of microporous osmotic tablets of diltiazem hydrochloride

    Directory of Open Access Journals (Sweden)

    Afifa Bathool

    2012-01-01

    Full Text Available Microporous osmotic tablet of diltiazem hydrochloride was developed for colon targeting. These prepared microporous osmotic pump tablet did not require laser drilling to deliver the drug to the specific site of action. The tablets were prepared by wet granulation method. The prepared tablets were coated with microporous semipermeable membrane and enteric polymer using conventional pan coating process. The incorporation of sodium lauryl sulfate (SLS, a leachable pore-forming agent, could form in situ delivery pores while coming in contact with gastrointestinal medium. The effect of formulation variables was studied by changing the amounts of sodium alginate and NaCMC in the tablet core, osmogen, and that of pore-forming agent (SLS used in the semipermeable coating. As the amount of hydrophilic polymers increased, drug release rate prolonged. It was found that drug release was increased as the concentration of osmogen and pore-former was increased. Fourier transform infrared spectroscopy and Differential scanning calorimetry results showed that there was no interaction between drug and polymers. Scanning electron microscopic studies showed the formation of pores after predetermined time of coming in contact with dissolution medium. The formation of pores was dependent on the amount of pore former used in the semipermeable membrane. in vitro results showed acid-resistant, timed release at an almost zero order up to 24 hours. The developed osmotic tablets could be effectively used for prolonged delivery of Diltiazem HCl.

  2. Root water extraction under combined water and osmotic stress

    NARCIS (Netherlands)

    Jong van Lier, de Q.; Dam, van J.C.; Metselaar, K.

    2009-01-01

    Using a numerical implicit model for root water extraction by a single root in a symmetric radial flow problem, based on the Richards equation and the combined convection-dispersion equation, we investigated some aspects of the response of root water uptake to combined water and osmotic stress. The

  3. Osmotic Adjustment in Leaves of VA Mycorrhizal and Nonmycorrhizal Rose Plants in Response to Drought Stress.

    Science.gov (United States)

    Augé, R M; Schekel, K A; Wample, R L

    1986-11-01

    Osmotic adjustment in Rosa hybrida L. cv Samantha was characterized by the pressure-volume approach in drought-acclimated and unacclimated plants brought to the same level of drought strain, as assayed by stomatal closure. Plants were colonized by either of the vesicular-arbuscular mycorrhizal fungi Glomus deserticola Trappe, Bloss and Menge or G. intraradices Schenck and Smith, or were nonmycorrhizal. Both the acclimation and the mycorrhizal treatments decreased the osmotic potential (Psi(pi)) of leaves at full turgor and at the turgor loss point, with a corresponding increase in pressure potential at full turgor. Mycorrhizae enabled plants to maintain leaf turgor and conductance at greater tissue water deficits, and lower leaf and soil water potentials, when compared with nonmycorrhizal plants. As indicated by the Psi(pi) at the turgor loss point, the active Psi(pi) depression which attended mycorrhizal colonization alone was 0.4 to 0.6 megapascals, and mycorrhizal colonization and acclimation in concert 0.6 to 0.9 megapascals, relative to unacclimated controls without mycorrhizae. Colonization levels and sporulation were higher in plants subjected to acclimation. In unacclimated hosts, leaf water potential, water saturation deficit, and soil water potential at a particular level of drought strain were affected most by G. intraradices. G. deserticola had the greater effect after drought preconditioning.

  4. Evaluation of structural fragilities for an IPEEE seismic probabilistic risk assessment study

    International Nuclear Information System (INIS)

    Ghiocel, D.M.; Wilson, P.R.; Stevenson, J.D.

    1995-01-01

    The paper presents the main issues and results of a structural fragility analysis for a Seismic Probabilistic Risk Assessment (SPRA) study of a nuclear power plant (NPP) in the Eastern US. The fragility evaluations were performed for the Reactor Building, Auxiliary Building, Intake Structure and Diesel Generator Building. The random seismic input is defined in terms of the Uniform Hazard Spectrum (UHS) earthquake on the NPP site anchored to a reference level of 0.40 g Zero Period Ground Acceleration (ZPGA). Because of the soft soil conditions new Soil-Structure Interaction (SSI) analyses were performed using the original finite element (stick) structural models and the complex frequency approach. The soil deposit randomness was described by the variations in both the low strain soil shear modules and in its dependence with the shear strain. The probabilistic SSI analyses were performed using digital simulation techniques. The critical failure modes for each structure are investigated and the fragility evaluations are discussed. Concluding remarks and recommendations for improving the quality of the structural fragility analyses are included

  5. Seismic Margin Assessment for Research Reactor using Fragility based Fault Tree Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kwag, Shinyoung; Oh, Jinho; Lee, Jong-Min; Ryu, Jeong-Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    The research reactor has been often subjected to external hazards during the design lifetime. Especially, a seismic event can be one of significant threats to the failure of structure system of the research reactor. This failure is possibly extended to the direct core damage of the reactor. For this purpose, the fault tree for structural system failure leading to the core damage under an earthquake accident is developed. The failure probabilities of basic events are evaluated as fragility curves of log-normal distributions. Finally, the plant-level seismic margin is investigated by the fault tree analysis combining with fragility data and the critical path is identified. The plant-level probabilistic seismic margin assessment using the fragility based fault tree analysis was performed for quantifying the safety of research reactor to a seismic hazard. For this, the fault tree for structural system failure leading to the core damage of the reactor under a seismic accident was developed. The failure probabilities of basic events were evaluated as fragility curves of log-normal distributions.

  6. Fragile X Syndrome: An Aging Perspective

    Science.gov (United States)

    Schneider, Andrea; Ligsay, Andrew; Hagerman, Randi J.

    2013-01-01

    Cognitive and behavioral correlates of molecular variations related to the FMR1 gene have been studied rather extensively, but research about the long-term outcome in individuals with fragile X spectrum disorders remains sparse. In this review, we present an overview of aging research and recent findings in regard to cellular and clinical…

  7. Fragility of superheated melts and glass-forming ability in Pr-based alloys

    International Nuclear Information System (INIS)

    Meng, Q.G.; Zhou, J.K.; Zheng, H.X.; Li, J.G.

    2006-01-01

    The kinetic viscosity (η) of superheated melts, thermal properties (T x , T m , T L ) and X-ray diffraction analysis on the Pr-based bulk metallic glasses (BMG) are reported and discussed. A new refined concept, the superheated fragility defined as M' = E S δ x /k B , has been developed based on common solidification theory and the Arrhenius equation. The interrelationship between this kind of fragility and the glass-forming ability (GFA) is elaborated on and evaluated in Pr-based BMG and Al-based amorphous ribbon alloys. Using viscosity data of superheated melts, it is shown, theoretically and experimentally, that the fragility parameter M' may be used as a GFA indicator for metallic alloys

  8. Osmotic actuation for microfluidic components in point-of-care applications

    KAUST Repository

    Chen, Yu-Chih; Ingram, Patrick; Lou, Xia; Yoon, Euisik

    2013-01-01

    at low cost. In this work, we report two key active components actuated by osmotic mechanism for total integrated microfluidic system. For the proof of concept, we have demonstrated valve actuation, which can maintain stable ON/OFF switching operations

  9. Banking Fragility in Colombia: An Empirical Analysis Based on Balance Sheets

    OpenAIRE

    Ignacio Lozano; Alexander Guarín

    2014-01-01

    In this paper, we study the empirical relationship between credit funding sources and the financial vulnerability of the Colombian banking system. We propose a statistical model to measure and predict banking-fragility episodes associated with credit funding sources classified into retail deposits and wholesale funds. We compute the probability of financial fragility for both the aggregated banking system and the individual banks. Our approach performs a Bayesian averaging of estimated logit ...

  10. The prospects for ecosystem services provision in fragile states’ urban areas

    OpenAIRE

    Bogadi, Antonija

    2018-01-01

    In fragile states context of climate change vulnerability, poverty and lack of infrastructure, the ability of ecosystem services to provide for numerous human needs is indispensable. The focus of this paper is describing the prospects for ecosystem services provision in fragile states’ urban areas. This paper presents a distinct approach by analyzing actors with capacity to provide ecosystem services in urban areas: government, international partners and citizens. Using infrastructure investm...

  11. Differential blood-brain barrier permeabilities to [14C]sucrose and [3H]inulin after osmotic opening in the rat

    International Nuclear Information System (INIS)

    Ziylan, Y.Z.; Robinson, P.J.; Rapoport, S.I.

    1983-01-01

    The blood-brain barrier (B-BB) in 3-month-old rats was opened unilaterally by infusing 1.8 m L(+)arabinose in water into the internal carotid artery through a catheter in the external carotid. Two poorly penetrating uncharged test radiotracers of differing molecular weight and size, [ 14 C]sucrose (340 daltons, radius 5 A) and [ 3 H]inulin (5500 daltons, radius 15 A), were simultaneously injected i.v. in untreated rats, or rats at 1, 30, or 50 min after infusion of hypertonic arabinose solution. Evans-blue solution was injected 5 min prior to osmotic treatment as a visual indicator of barrier integrity. In regions of uninfused control brains, the [ 14 C]sucrose permeability-surface area (PA) product approximated 10(-5) s-1, whereas PA was not measurable for [ 3 H]inulin. In arabinose-infused animals, PA products on the ipsilateral hemisphere for both [ 14 C]sucrose and [ 3 H]inulin were markedly elevated 6 min after infusion, but decreased by 35 and 55 min. In nearly all regions, statistically significant differences were not found between 6-min [ 14 C]sucrose- and [ 3 H]inulin-PA values (P greater than 0.05). However, at 35 and 55 min in most regions, the PA for [ 3 H]inulin was significantly lower (P less than 0.05) than PA for [ 14 C]sucrose. The results indicated that the B-BB closed more rapidly to larger than to smaller molecules after osmotic treatment and were consistent with a pore model for osmotic B-BB opening

  12. Fragile X premutation in women: recognizing the health challenges beyond primary ovarian insufficiency.

    Science.gov (United States)

    Hoyos, Luis R; Thakur, Mili

    2017-03-01

    Fragile X premutation carriers have 55-200 CGG repeats in the 5' untranslated region of the FMR1 gene. Women with this premutation face many physical and emotional challenges in their life. Approximately 20% of these women will develop fragile X-associated primary ovarian insufficiency (FXPOI). In addition, they suffer from increased rates of menstrual dysfunction, diminished ovarian reserve, reduction in age of menopause, infertility, dizygotic twinning, and risk of having an offspring with a premutation or full mutation. Consequent chronic hypoestrogenism may result in impaired bone health and increased cardiovascular risk. Neuropsychiatric issues include risk of developing fragile X-associated tremor/ataxia syndrome, neuropathy, musculoskeletal problems, increased prevalence of anxiety, depression, and sleep disturbances independent of the stress of raising an offspring with fragile X syndrome and higher risk of postpartum depression. Some studies have reported a higher prevalence of thyroid abnormalities and hypertension in these women. Reproductive health providers play an important role in the health supervision of women with fragile X premutation. Awareness of these risks and correlation of the various manifestations could help in early diagnosis and coordination of care and services for these women and their families. This paper reviews current evidence regarding the possible conditions that may present in women with premutation-sized repeats beyond FXPOI.

  13. Side Effects of Minocycline Treatment in Patients with Fragile X Syndrome and Exploration of Outcome Measures

    Science.gov (United States)

    Utari, Agustini; Chonchaiya, Weerasak; Rivera, Susan M.; Schneider, Andrea; Hagerman, Randi J.; Faradz, Sultana M. H.; Ethell, Iryna M.; Nguyen, Danh V.

    2010-01-01

    Minocycline can rescue the dendritic spine and synaptic structural abnormalities in the fragile X knock-out mouse. This is a review and preliminary survey to document side effects and potential outcome measures for minocycline use in the treatment of individuals with fragile X syndrome. We surveyed 50 patients with fragile X syndrome who received…

  14. Carbon dioxide enhances fragility of ice crystals

    International Nuclear Information System (INIS)

    Qin Zhao; Buehler, Markus J

    2012-01-01

    Ice caps and glaciers cover 7% of the Earth, greater than the land area of Europe and North America combined, and play an important role in global climate. The small-scale failure mechanisms of ice fracture, however, remain largely elusive. In particular, little understanding exists about how the presence and concentration of carbon dioxide molecules, a significant component in the atmosphere, affects the propensity of ice to fracture. Here we use atomic simulations with the first-principles based ReaxFF force field capable of describing the details of chemical reactions at the tip of a crack, applied to investigate the effects of the presence of carbon dioxide molecules on ice fracture. Our result shows that increasing concentrations of carbon dioxide molecules significantly decrease the fracture toughness of the ice crystal, making it more fragile. Using enhanced molecular sampling with metadynamics we reconstruct the free energy landscape in varied chemical microenvironments and find that carbon dioxide molecules affect the bonds between water molecules at the crack tip and decrease their strength by altering the dissociation energy of hydrogen bonds. In the context of glacier dynamics our findings may provide a novel viewpoint that could aid in understanding the breakdown and melting of glaciers, suggesting that the chemical composition of the atmosphere can be critical to mediate the large-scale motion of large volumes of ice.

  15. Analyzing the effects of mechanical and osmotic loading on glycosaminoglycan synthesis rate in cartilaginous tissues.

    Science.gov (United States)

    Gao, Xin; Zhu, Qiaoqiao; Gu, Weiyong

    2015-02-26

    The glycosaminoglycan (GAG) plays an important role in cartilaginous tissues to support and transmit mechanical loads. Many extracellular biophysical stimuli could affect GAG synthesis by cells. It has been hypothesized that the change of cell volume is a primary mechanism for cells to perceive the stimuli. Experimental studies have shown that the maximum synthesis rate of GAG is achieved at an optimal cell volume, larger or smaller than this level the GAG synthesis rate decreases. Based on the hypothesis and experimental findings in the literature, we proposed a mathematical model to quantitatively describe the cell volume dependent GAG synthesis rate in the cartilaginous tissues. Using this model, we investigated the effects of osmotic loading and mechanical loading on GAG synthesis rate. It is found our proposed mathematical model is able to well describe the change of GAG synthesis rate in isolated cells or in cartilage with variations of the osmotic loading or mechanical loading. This model is important for evaluating the GAG synthesis activity within cartilaginous tissues as well as understanding the role of mechanical loading in tissue growth or degeneration. It is also important for designing a bioreactor system with proper extracellular environment or mechanical loading for growing tissue at the maximum synthesis rate of the extracellular matrix. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Ionic and osmotic relations in quinoa (Chenopodium quinoa Willd.) plants grown at various salinity level

    DEFF Research Database (Denmark)

    Hariadi, Yuda; Marandon, Karl; Tian, Yu

    2011-01-01

    or by the gradual increase of NaCl levels in the irrigation water. For both methods, the optimal plant growth and biomass was achieved between 100 mM and 200 mM NaCl, suggesting that quinoa possess a very efficient system to adjust osmotically for abrupt increases in NaCl stress. Up to 95% of osmotic adjustment......Cl-induced activation of H+-ATPase is needed to restore otherwise depolarized membrane potential and prevent further K+ leak from the cytosol. Taken together, this work emphasizes the role of inorganic ions for osmotic adjustment in halophytes and calls for more in-depth studies of the mechanisms of vacuolar Na...

  17. An Investigation of Narrative Ability in Boys with Autism and Fragile X Syndrome

    Science.gov (United States)

    Hogan-Brown, Abigail L.; Losh, Molly; Martin, Gary E.; Mueffelmann, Deborah J.

    2013-01-01

    Whereas pragmatic language difficulties are characteristic of both autism and Fragile X syndrome, it is unclear whether such deficits are qualitatively similar or whether certain skills are differentially affected. This study compared narrative competence in boys with autism, Fragile X syndrome, Down syndrome, and typical development. Results…

  18. Augmentation of peristaltic microflows through electro-osmotic mechanisms

    International Nuclear Information System (INIS)

    Chakraborty, Suman

    2006-01-01

    The present work aims to theoretically establish that the employment of an axial electric field can substantially augment the rate of microfluidic transport occurring in peristaltic microtubes. For theoretical analysis, shape evolution of the tube is taken to be arbitrary, except for the fact that the characteristic wavelength is assumed to be significantly greater than the average radius of cross section. First, expressions for the velocity profile within the tube are derived and are subsequently utilized to obtain variations in the net flow rate across the same, as a function of the pertinent system parameters. Subsequently, the modes of interaction between the electro-osmotic and peristaltic mechanisms are established through the variations in the time-averaged flow rates for zero pressure rise and the pressure rise for zero time-averaged flow rates, as expressed in terms of the occlusion number, characteristic electro-osmotic velocity and the peristaltic wave speed. From the simulation predictions, it is suggested that a judicious combination of peristalsis and an axial electrokinetic body force can drastically enhance the time-averaged flow rate, provided that the occlusion number is relatively small

  19. Alleviation of osmotic stress of water and salt in germination and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-04

    Jul 4, 2008 ... ening, osmoconditioning, osmohardening, and hormonal priming have ... germination, emergence and plant growth of wheat (Das and Choudhury .... In the present study, a significant three way interaction. (osmotic agents ...

  20. A REVIEW ON OSMOTIC DRUG DELIVERY SYSTEM

    OpenAIRE

    Harnish Patel; Upendra Patel; Hiren Kadikar; Bhavin Bhimani; Dhiren Daslaniya; Ghanshyam Patel

    2012-01-01

    Conventional oral drug delivery systems supply an instantaneous release of drug, which cannot control the release of the drug and effective concentration at the target site. This kind of dosing pattern may result in constantly changing, unpredictable plasma concentrations. Drugs can be delivered in a controlled pattern over a long period of time by the process of osmosis. Osmotic devices are the most promising strategy based systems for controlled drug delivery. They are the most reliable con...