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Sample records for leucocyte migration test

  1. The effect of thyroid antigens on the in vitro migration of leucocytes from patients with Hashimoto thyroiditis

    Science.gov (United States)

    Calder, Elizabeth A.; McLeman, Dena; Barnes, E. W.; Irvine, W. J.

    1972-01-01

    A total of fifty-two patients with Hashimoto thyroiditis were tested for delayed hypersensitivity to thyroid antigens using the leucocyte migration test. The percentage of patients showing abnormal migration in the presence of crude thyroid extract, thyroglobulin, thyroid mitochondria and thyroid microsomes was 75, 44, 54 and 34% respectively. Fifty-three control patients were studied concurrently with the same antigens and the percentage showing abnormal migration was 4, 6, 6 and 6% respectively. The antigenic activity of the mitochondrial fraction was not organ specific; both liver and kidney mitochondria interfered with the migration of leucocytes from patients with Hashimoto thyroiditis. PMID:4568149

  2. Assessment of correlation between leucocytes migration reaction and level of inhalation exposure to priority air contaminants

    Directory of Open Access Journals (Sweden)

    L.B. Masnavieva

    2017-09-01

    Full Text Available Nowadays each forth person suffers from allergic diseases and allergic pathology prevalence is constantly growing. There are compounds in air which are generally toxic, or have sensitizing or allergenic effects on a body. For example, we can name formaldehyde and nitrogen dioxide. Our research goal was to reveal a correlation between reaction of leucocytes migration inhibition to formaldehyde and level of inhalation exposure to the examined chemicals. We examined 410 teenag-ers who permanently lived in industrial cities in Irkutsk region. We studied individual load as per formaldehyde and nitrogen dioxide. We estimated eosinophils content in nasal mucus and determined indexes of leucocytes migration inhibition to for-maldehyde. Index of formaldehyde effects danger was detected to exceed 1 in 54% teenagers. The greatest value of danger coefficient in terms of exposure to this substance was equal to 1.76. anger index in terms of exposure to nitrogen dioxide didn't exceed 0.7 in the examined teenagers. The obtained results prove that inhalation formaldehyde load influences teenag-ers from industrial centers as sensitization to this substance evolves in them. We found out that true inhibition reaction of leucocytes migration in a reaction with formaldehyde more frequently occurred in people with danger index in terms of ex-posure to this substance being lower than 1. We obtained models which described correlation between level of sensitization to formaldehyde and a number of eosinophils in nasal mucus and it allowed us to detect that sensitization depended on the examined contaminants content in the air. The sensitization to chemical air contaminants which we revealed in teenagers calls for necessary activities aimed at reducing risks of allergenic pathology evolvement in them.

  3. Inhibition of human polimorfonuclear leucocyte migration by clofazimine: a new pro-oxidative anti-inflammatory agent

    International Nuclear Information System (INIS)

    Jansen van Rensburg, C.E.

    1986-10-01

    Preliminary studies on the in vitro and in vivo effects of clofazimine on the function of polymorphonuclear leucocytes (PMNL) from normal individuals and patients with lepromatous leprosy showed that clofazimine caused a progressive dose-dependent inhibition of both random mortality of PMNL as well as migration of PMNL induced by the leucoattractant endotoxin-activated serum (EAS). The drug also increased chemiluminescence as well as hexose monophosphate shunt (HMS). These studies on clofazimine include the use of radiolabelling with 14 C, 125 I and 3 H. Clofazimine-mediated inhibition of PMNL migration is dependent on intact membrane-associated oxidative metabolism. Clofazimine is therefore a pro-oxidative anti-inflammatory agent

  4. Time-lapse cinematography of the capillary tube cell migration inhibition test.

    Science.gov (United States)

    Bray, M A

    1980-01-01

    The kinetics of human and guinea pig cell migration inhibition have been studied using time-lapse cinematography of cells migrating from capillary tubes. Guinea pig and human cells exhibit markedly different kinetics in the absence of inhibitors. Specific antigen causes a dose-related inhibition of migration for up to 60 h using guinea pig cells and a peak of inhibition after 18 h using the human leucocyte system. The timing of measurement of maximum activity more critical for the latter test. The kinetics of lymphokine generation have been examined and the migration inhibitory activity of the plant mitogen (PHA), a Kurloff cell product and a continuous cell line supernatant have been compared with the inhibitory profiles of lymphokine preparations and specific antigen.

  5. A rapid method for the preparation of 99Tcm hexametazime-labelled leucocytes

    International Nuclear Information System (INIS)

    Solanki, K.K.; Mather, S.J.; Janabi, M.A.; Britton, K.E.

    1988-01-01

    99 Tc m (±)-hexamethylpropyleneamineoxime (HMPAO) ( 99 Tc m Hexametazime) has been recently reported as an alternative for labelling leucocytes. This technique has been modified to give a simpler routine in-house labelling technique. It has three advantages: only about 20 ml of blood is required, the labelling time is just under 1 h and high yields of labelled leucocytes are obtained (mean of 500 MBq per injection dose). The properties of labelled leucocytes using this modified method are; 80% granulocyte-bound radioactivity, a rapid lung transit and a blood granulocyte recovery of 40% at 30 min similar to those described previously. The viability of the labelled leucocytes was tested and confirmed in vitro using a migration technique and in vivo by showing no lung retention on early imaging and high splenic uptake. A rapid in-process chromatography assessment procedure for regulating the protocol has been developed. Successful abscess imaging by 4 h has been achieved in 21 patients with normal results in another 22 patients without abscesses. This simpler method should encourage a more widespread application of scintigraphy using radiolabelled granulocytes. (author)

  6. The migration of 111Indium-labelled polymorphonuclear leucocytes into the oral cavity in the rhesus monkey

    International Nuclear Information System (INIS)

    Scully, C.; Challacombe, S.J.

    1979-01-01

    The route of migration of polymorphonuclear leucocytes (PMNL) from blood to the oral cavity was examined in rhesus monkeys. PMNL were isolated from the peripheral blood of eleven rhesus monkeys by dextran sedimentation, radiolabelled with 111 Indium and administered intravenously. Sequential samples of crevicular fluid washings (CFW), mixed and parotid saliva and mucosal washings were taken after injection of the labelled PMNL and harvested on glass fibre discs. Highest numbers of labelled PMNL were detected in CFW. CEll-associated radioactivity was detected in CFW within 20 min of injection of labelled PMNL and reached a maximal level 1 hour after injection. PMNL were found in CFW from monkeys with clinically normal gingiva but the number of labelled PMNL in CFW increased with increasing gingival index. Significant number of PMNL migrated into mixed saliva within 30 min, and low numbers of PMNL were detected in mucosal washings and in parotid saliva after 30 min. The results indicate that the migration time of the PMNL from blood to the oral cavity is less than 30 min, irrespective of the gingival index, that the gingival crevice is the main route of entry of PMNL to the oral cavity and that the numbers of PMNL migrating to the crevice increase as the gingival index rises. (author)

  7. The Fps/Fes kinase regulates leucocyte recruitment and extravasation during inflammation.

    Science.gov (United States)

    Parsons, Sean A; Mewburn, Jeffrey D; Truesdell, Peter; Greer, Peter A

    2007-12-01

    Fps/Fes and Fer comprise a distinct subfamily of cytoplasmic protein-tyrosine kinases, and have both been implicated in the regulation of innate immunity. Previous studies showed that Fps/Fes-knockout mice were hypersensitive to systemic lipopolysaccharide (LPS) challenge, and Fer-deficient mice displayed enhanced recruitment of leucocytes in response to localized LPS challenge. We show here for the first time, a role for Fps in the regulation of leucocyte recruitment to areas of inflammation. Using the cremaster muscle intravital microscopy model, we observed increased leucocyte adherence to venules, and increased rates and degrees of transendothelial migration in Fps/Fes-knockout mice relative to wild-type animals subsequent to localized LPS challenge. There was also a decreased vessel wall shear rate in the post-capillary venules of LPS-challenged Fps/Fes-knockout mice, and an increase in neutrophil migration into the peritoneal cavity subsequent to thioglycollate challenge. Using flow cytometry to quantify the expression of surface molecules, we observed prolonged expression of the selectin ligand PSGL-1 on peripheral blood neutrophils from Fps/Fes-knockout mice stimulated ex vivo with LPS. These observations provide important insights into the observed in vivo behaviour of leucocytes in LPS-challenged Fps/Fes-knockout mice and provide evidence that the Fps/Fes kinase plays an important role in the innate immune response.

  8. Differential centrifugation of leucocytes and platelets applied to 111In-leucocyte labelling

    International Nuclear Information System (INIS)

    Mountford, P.J.

    1986-01-01

    Platelet contamination of 111 In-leucocytes can be minimized by centrifugation of leucocyte-rich plasma before labelling. The differential recovery of leucocytes and platelets from centrifugation depends on various biological and physical factors. Experimental measurements have been made of the effect of some of these factors. The ratio of leucocyte-to-platelet recovery was increased by using more than one centrifugation, and by using a low relative centrifugal force (RCF). To extend the study, a method of calculating cell recovery from centrifugation was developed, based on the experimental results. Calculations indicated that this ratio was at a maximum at around 85g RCF, and was least affected by changes in the suspension medium viscosity. At 85g, leucocyte recovery was incomplete, but calculations indicated that there was a preferential recovery of granulocytes which was subsequently verified by experiment. (author)

  9. Validity of total leucocytes count and neutrophil count (differential leucocytes) in diagnosing suspected acute appendicitis

    International Nuclear Information System (INIS)

    Anwar, M.W.; Abid, I.

    2012-01-01

    Objective: To compare the diagnostic accuracy of Total Leucocytes Count (TLC) with Neutrophil count; Differential Leucocytes Count (DLC) in diagnosing cases of suspected acute appendicitis. Study design: Validation study. Place and duration of the study: Department of Surgery, Combined Military Hospital (CMH) Rawalpindi, from April 2008 to October 2008. Method: A total of 100 patients of Pain right iliac fossae who underwent appendicectomy were included. Detailed history of all the patients was taken for pain in right lower abdomen, its severity, its nature, relieving or provoking factors. Clinical examination was done in detail. Total and Differential Leucocytes Count was done. Every patient's appendix was examined grossly after appendicectomy for evidence of appendicitis. Diagnostic measures of TLC and DLC were calculated by standard formulas. Results: Sensitivity and specificity of TLC is 86.9% and 81.25% respectively and that of DLC is 82% and 68.75% respectively. Accuracy was 86% for TLC and 80% for DLC. Conclusion: TLC is more sensitive, specific and accurate test as compared to DLC and it should be used as diagnostic aid for suspected acute appendicitis cases. (author)

  10. Comparison of Effects of Running and Playing Exercises on Differential Leucocyte Count in Young Elite Athletes

    Science.gov (United States)

    Cenikli, Abdullah

    2016-01-01

    The aims of the present research are to test the effects of running and playing exercises on leucocyte and differential leucocyte accounts, and to test the possible differences between running and playing exercises in terms of leucocyte accounts. They were thirty two male young soccer players. Participants arrived at the laboratory after a 12-hour…

  11. [Evaluation of the mutagenicity of detergents by tests on bacteria, plant cells and human leucocytes.].

    Science.gov (United States)

    Feretti, Donatella; Pedrazzani, Roberta; Ceretti, Elisabetta; Zerbini, Ilaria; Gozio, Eleonora; Belotti, Caterina; Alias, Carlotta; Donato, Francesco; Gelatti, Umberto

    2009-01-01

    The aim of this study was to evaluate the mutagenicity of several traditional detergents and that of newer more biodegradable detergents, by using a bacterial test (Ames test), a plant cell test (Allium cepa micronuclei test) and a human leucocyte test (Comet test). All tests were conducted using a wide range of doses (1-2000 mg/l). None of the examined detergents induced mutations in S.typhimurium. One traditional detergent showed a genotoxic effect with the A. cepa test, while all newer detergents and one traditional detergent were shown by the Comet test to be capable of inducing DNA damage.

  12. Donor leucocyte imaging in patients with AIDS: A preliminary report

    International Nuclear Information System (INIS)

    O'Doherty, M.J.; Kent and Canterbury Hospital; Revell, P.; Page, C.J.; Nunan, T.O.; Lee, S.; Mountford, P.J.

    1990-01-01

    Four patients with the acquired immunodeficiency syndrome (AIDS) and fever were investigated using donor leucocyte scans. The lung/liver and lung/spleen uptake ratios in these patients were compared with the uptake ratios in donor leucocyte scans in seven neutropenic (non-AIDS) patients and five patients who had autologous leucocyte scans performed over the same time period. All scans used indium oxine In 111 labelled leucocytes except that for one AIDS patient which used technetium hexamethyl-propylene amine oxide Tc99m labelled donor leucocytes. There were no adverse reactions to the donor cell infusions. Two patients had repeat studies 8 weeks apart (from different donors) without ill effect. There were no differences in the 111 In uptake ratios between the three groups. There were three positive studies in the patients with AIDS, and these elucidated the cause of the pyrexia in all three. The negative case is more difficult to confirm, but the clinical course and the absence of focal disease on post-mortem have been taken to support the scan findings. There was no difference in the acceptibility of the technique or the distribution of the labelled leucocytes between the AIDS and non-AIDS patients. Donor leucocyte imaging of patients with AIDS is probably more effective and considerably less hazardous for technical staff than autologous leucocyte methods. This study demonstrates that the technique can be applied successfully to patients with AIDS. (orig.)

  13. 99Tcm-labelled leucocyte imaging in active rheumatoid arthritis

    International Nuclear Information System (INIS)

    Al-Janabi, M.A.; Jones, A.K.P.; Solanki, K.; Sobnack, R.; Bomanji, J.; Al-Nahhas, A.A.; Britton, K.E.; Huskisson, E.C.; Doyle, D.V.

    1988-01-01

    A simplified technique of labelling leucocytes with technetium-99m is described and applied to patients with active rheumatoid arthritis. The clinically active and less active knees in seven patients were imaged and the uptake of labelled leucocytes was measured. The measurements were repeated after local steroid injection into nine painful knees. A 50-80% reduction in leucocyte uptake localized to the region of the synovium was demonstrated in the eight knees which showed clinical responses and a rise of 8% in the non-responder. There was a variable response in the knees that were not injected. 99 Tc m leucocyte imaging in rheumatoid arthritis is able to assess objectively joint inflammation and its response to treatment. (author)

  14. Vitamin C in plasma and leucocytes in relation to periodontitis

    NARCIS (Netherlands)

    Kuzmanova, D.; Jansen, I.D.C.; Schoenmaker, T.; Nazmi, K.; Teeuw, W.J.; Bizzarro, S.; Loos, B.G.; van der Velden, U.

    2012-01-01

    Aim To test the hypothesis that vitamin C concentrations in plasma, polymorphonuclear neutrophilic leucocytes (PMNs) and peripheral blood mononuclear cells (PBMCs) are lower in periodontitis patients compared with healthy controls. Methods Twenty-one untreated periodontal patients and 21 healthy

  15. Field tests on migration of TRU-nuclide, (2). Migration test for engineered barrier materials in aerated soil

    International Nuclear Information System (INIS)

    Maeda, Toshikatsu; Tanaka, Tadao; Mukai, Masayuki

    2003-01-01

    Field tests on migration of radionuclides for engineered barrier materials such as bentonite and cementitious materials were performed. The tests were run under both wet conditions with artificial rainfall and dry conditions with natural rainfall. Laboratory experiments such as batch adsorption tests were also conducted to analyze the result of field test. The results of field tests agreed with the predicted moisture conditions and the migration behaviors observed at the laboratory experiment that is reported so far. For bentonite material, the movements of the tracer were calculated using known information such as the results of batch sorption tests and migration mechanism. Comparing the result of field test and calculations, it is suggested that tracer migration behavior in bentonite material in field can be evaluated quantitatively by the known migration mechanism and the results of laboratory experiments such as batch sorption test. (author)

  16. Stabilization of Tc-99m D,L-HMPAO preparations as a leucocyte labelling agent

    International Nuclear Information System (INIS)

    Kao, C.H.; Huang, W.T.; Tsai, C.S.

    1998-01-01

    An attempt was made to use stabilized Tc-99m D,L-HMPAO (S-HMPAO) to label leucocytes. The radiochemical purity of Tc-99m D,L-HMPAO, labelling efficiency of leucocytes, cell viability of labelled leucocytes, and stability of S-HMPAO labelled leucocytes were calculated. In comparison with commercial Tc-99m D,L-HMPAO (C-HMPAO) without stabilization, immediately, at 0.5, 1, 2, 4, and 6 h after HMPAO preparation, the radiochemical purity of S-HMPAO and the labelling efficiencies of S-HMPAO labelled leucocytes were higher. S-HMPAO is more stable than C-HMPAO and can provide higher leucocyte labelling efficiency. S-HMPAO, therefore, has the potential to replace C-HMPAO as a leucocyte-labelling agent

  17. Labelling of leucocytes with 18 F-FDG

    International Nuclear Information System (INIS)

    Tomas, M.B.; Tronco, G.G.; Palestro, C.J.

    2003-01-01

    Full text: Objective: To investigate the effect of blood glucose levels on in-vitro 18 F-FDG labeling of autologous leucocytes. Methods: Seventeen volunteers, 11 men and 6 women, 20 - 54 years old, participated in this study. Using standard techniques, a mixed leucocyte suspension was prepared from 40 ml of blood withdrawn from each volunteer. Blood glucose levels were also measured for each blood sample. After resuspension in 3 ml heparinized saline, the leucocytes were incubated with 11.03 (± 4.48) mCi 18 F-FDG for 30 minutes at 370 C. The labeled cell suspension was then centrifuged for 5 min (150 g). Activity in the cell pellet and supernatant were measured and labelling efficiency calculated. Results: Blood glucose levels ranged from 80 to 178 mg% with a mean of 113 mg%. The overall labelling efficiency was 61.2% (±7.3%). The mean labelling efficiency for blood glucose levels 100 mg%. There is no statistically significant difference between the labeling efficiencies obtained at blood glucose levels 100 mg% (p =0.72). Blood Glucose Level (mg%) Labelling Efficiency (%) 100 61. Conclusion: In summary, no correlation between blood glucose levels and labeling efficiency was observed. Blood glucose levels up to 178 mg% do not affect 18 F-FDG in-vitro labelling of autologous leucocytes. (author)

  18. Peripheral Blood Leucocyte Apoptosis in Two Dogs Infected with ...

    African Journals Online (AJOL)

    Blood leucocyte apoptosis in the trypanosome-infected natural hosts is yet to be documented and recognized as a feature of trypanosomiasis. We provide evidence of marked peripheral blood leucocyte apoptosis in two cases of dogs severely infected with Trypanosoma congolense. It is expected that this case report will ...

  19. Platelets Inhibit Migration of Canine Osteosarcoma Cells.

    Science.gov (United States)

    Bulla, S C; Badial, P R; Silva, R C; Lunsford, K; Bulla, C

    2017-01-01

    The interaction between platelets and tumour cells is important for tumour growth and metastasis. Thrombocytopenia or antiplatelet treatment negatively impact on cancer metastasis, demonstrating potentially important roles for platelets in tumour progression. To our knowledge, there is no information regarding the role of platelets in cancer progression in dogs. This study was designed to test whether canine platelets affected the migratory behaviour of three canine osteosarcoma cell lines and to give insights of molecular mechanisms. Intact platelets, platelet lysate and platelet releasate inhibited the migration of canine osteosarcoma cell lines. Addition of blood leucocytes to the platelet samples did not alter the inhibitory effect on migration. Platelet treatment also significantly downregulated the transcriptional levels of SNAI2 and TWIST1 genes. The interaction between canine platelets or molecules released during platelet activation and these tumour cell lines inhibits their migration, which suggests that canine platelets might antagonize metastasis of canine osteosarcoma. This effect is probably due to, at least in part, downregulation of genes related to epithelial-mesenchymal transition. Copyright © 2016. Published by Elsevier Ltd.

  20. The apparent and effective chloride migration coefficients obtained in migration tests

    NARCIS (Netherlands)

    Spiesz, P.R.; Brouwers, H.J.H.

    2013-01-01

    The apparent (Dapp) and effective (Deff) migration coefficients obtained in chloride migration tests are investigated in this study. The presented Dapp profiles in concrete show that the apparent migration coefficient is strongly concentration-dependent. As demonstrated, the binding of chlorides is

  1. Computer Aided Solution for Automatic Segmenting and Measurements of Blood Leucocytes Using Static Microscope Images.

    Science.gov (United States)

    Abdulhay, Enas; Mohammed, Mazin Abed; Ibrahim, Dheyaa Ahmed; Arunkumar, N; Venkatraman, V

    2018-02-17

    Blood leucocytes segmentation in medical images is viewed as difficult process due to the variability of blood cells concerning their shape and size and the difficulty towards determining location of Blood Leucocytes. Physical analysis of blood tests to recognize leukocytes is tedious, time-consuming and liable to error because of the various morphological components of the cells. Segmentation of medical imagery has been considered as a difficult task because of complexity of images, and also due to the non-availability of leucocytes models which entirely captures the probable shapes in each structures and also incorporate cell overlapping, the expansive variety of the blood cells concerning their shape and size, various elements influencing the outer appearance of the blood leucocytes, and low Static Microscope Image disparity from extra issues outcoming about because of noise. We suggest a strategy towards segmentation of blood leucocytes using static microscope images which is a resultant of three prevailing systems of computer vision fiction: enhancing the image, Support vector machine for segmenting the image, and filtering out non ROI (region of interest) on the basis of Local binary patterns and texture features. Every one of these strategies are modified for blood leucocytes division issue, in this manner the subsequent techniques are very vigorous when compared with its individual segments. Eventually, we assess framework based by compare the outcome and manual division. The findings outcome from this study have shown a new approach that automatically segments the blood leucocytes and identify it from a static microscope images. Initially, the method uses a trainable segmentation procedure and trained support vector machine classifier to accurately identify the position of the ROI. After that, filtering out non ROI have proposed based on histogram analysis to avoid the non ROI and chose the right object. Finally, identify the blood leucocytes type using

  2. In vivo measurement of circulating leucocyte activation in patients following cardiopulmonary bypass

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Hazel A. E-mail: hazel.jones@imperial.ac.uk; Choudhury, Marina; Harris, David N.F

    2004-10-01

    We have developed a simple technique to measure in vivo activation of circulating leucocytes and assessed it in 6 patients undergoing cardiopulmonary bypass (CPB). Arterial, mixed venous, and jugular bulb blood samples were taken following i.v. [{sup 18}F]FDG, before and after CPB. [{sup 18}F]FDG uptake in leucocytes was measured by phosphor imaging of spun blood-filled capillary tubes. Leucocyte radioactivity was quantified ([(leucocytes-plasma)/plasma radioactivity] and normalised to leucocyte counts. [{sup 18}F]FDG uptake (mean{+-}SEM)) before CPB was undetectable, being -0.014{+-}0.007, -0.011{+-}0.003, -0.012{+-}0.006, -0.010{+-}0.005, whereas increased uptake was demonstrated following CPB, 0.006{+-}0.006, 0.009{+-}0.005, 0.021{+-}0.005, 0.034{+-}0.006, at 20, 40, 60, and 80 min, respectively. There was no significant difference in activation between sampling sites before or after CPB. This method gives a sensitive index of activation of circulating leucocytes in whole blood, enabling investigation of activation of circulating white cells without the influence of sample handling or the requirement for time-consuming cell separation procedures.

  3. Isolation and labelling of human leucocytes with sup(99m)Tc

    International Nuclear Information System (INIS)

    Kalbaek, H.

    1986-01-01

    The role of the leucocyte isolation procedure on cell labeling with sup(99m)Tc has been evaluated. Separation of leucocytes was performed by two procedures: (1) sedimentation on methyl cellulose, followed by discontinuous gradient centrifugation; (2) methyl cellulose sedimentation and hypotonic haemolysis of residual red blood cells. After washing the cells in saline and incubation with a stannous pyrophosphate agent, the leucocytes were labelled with 5-10 mCi sup(99m)Tc. Procedure 1 gave a higher purity but lower recovery of polymorphonuclear leucocytes, and a minor contamination of red blood cells. sup(99m)Tc labelling of cells was slightly more efficient with this method, probably due to the presence of red blood cells. Procedure 1 is recommended for in vitro studies on cell kinetics and procedure 2 is recommended for clinical use. (orig.)

  4. Body surface dosimetry following re-injection of 111In-leucocytes

    International Nuclear Information System (INIS)

    Mountford, P.J.; Coakley, A.J.

    1989-01-01

    The dose to a young infant cared for by a parent re-injected with 111 In-leucocytes was estimated from the exposure of thermoluminescent dosimeters at five sites on the chest wall of eight patients. The UK Guidance Notes recommend that patients with a residual activity exceeding 20 MBq of 111 In should avoid non-essential contact with children. The results confirmed those of an earlier preliminary study which showed that re-injection of 20 MBq of 111 In-leucocytes to a parent could lead to a close contact dose greater than 1 mSv. It was concluded that the 111 In-leucocyte activity administered to a parent of a young infant should not exceed 10 MBq. (author)

  5. Bothrops asper snake venom and its metalloproteinase BaP–1 activate the complement system. Role in leucocyte recruitment

    Directory of Open Access Journals (Sweden)

    Sandra H. P. Farsky

    2000-01-01

    Full Text Available The venom of the snake Bothrops asper, the most important poisonous snake in Central America, evokes an inflammatory response, the mechanisms of which are not well characterized. The objectives of this study were to investigate whether B. asper venom and its purified toxins – phospholipases and metalloproteinase – activate the complement system and the contribution of the effect on leucocyte recruitment. In vitro chemotaxis assays were performed using Boyden's chamber model to investigate the ability of serum incubated with venom and its purified toxins to induce neutrophil migration. The complement consumption by the venom was evaluated using an in vitro haemolytic assay. The importance of complement activation by the venom on neutrophil migration was investigated in vivo by injecting the venom into the peritoneal cavity of C5-deficient mice. Data obtained demonstrated that serum incubated with crude venom and its purified metalloproteinase BaP–1 are able to induce rat neutrophil chemotaxis, probably mediated by agent(s derived from the complement system. This hypothesis was corroborated by the capacity of the venom to activate this system in vitro. The involvement of C5a in neutrophil chemotaxis induced by venom-activated serum was demonstrated by abolishing migration when neutrophils were pre-incubated with antirat C5a receptor antibody. The relevance of the complement system in in vivo leucocyte mobilization was further demonstrated by the drastic decrease of this response in C5-deficient mice. Pre-incubation of serum with the soluble human recombinant complement receptor type 1 (sCR 1 did not prevent the response induced by the venom, but abolished the migration evoked by metalloproteinase-activated serum. These data show the role of the complement system in bothropic envenomation and the participation of metalloproteinase in the effect. Also, they suggest that the venom may contain other component(s which can cause direct activation

  6. Leucocyte esterase dip-stick test as a point-of-care diagnostic for urogenital chlamydia in male patients: A multi-center evaluation in two STI outpatient clinics in Paramaribo and Amsterdam

    NARCIS (Netherlands)

    Bartelsman, Menne; de Vries, Henry J. C.; Schim van der Loeff, Maarten F.; Sabajo, Leslie O. A.; van der Helm, Jannie J.

    2016-01-01

    Point-of-care (POC) tests are an important strategy to address the epidemic of sexually transmitted infections (STIs). The leucocyte esterase test (LET) can be used as a POC test for chlamydia. The aim of this study was to determine the diagnostic accuracy of the LET to detect urogenital chlamydia

  7. Leucocyte esterase in the rapid diagnosis of paediatric septic arthritis.

    LENUS (Irish Health Repository)

    Kelly, E G

    2013-02-01

    Septic arthritis may affect any age group but is more common in the paediatric population. Infection is generally bacterial in nature. Prompt diagnosis is crucial, as delayed treatment is associated with lifelong joint dysfunction. A clinical history and application of Kocher\\'s criteria may indicate that there is a septic arthritis. However, definitive diagnosis is made on culture of septic synovial fluid. The culture process can take over 24h for the initial culture to yield bacterial colonies. Leucocyte esterase is released by leucocytes at the site of an infection. We hypothesise that leucocyte esterase can be utilized in the rapid diagnosis of septic arthritis and shorten the time to decisive treatment whilst simultaneously decreasing unnecessary treatment of non-septic joints.

  8. Radiation enteropathy and leucocyte-endothelial cell reactions in a refined small bowel model

    Directory of Open Access Journals (Sweden)

    Osman Nadia

    2004-09-01

    Full Text Available Abstract Background Leucocyte recruitment and inflammation are key features of high dose radiation-induced tissue injury. The inflammatory response in the gut may be more pronounced following radiotherapy due to its high bacterial load in comparison to the response in other organs. We designed a model to enable us to study the effects of radiation on leucocyte-endothelium interactions and on intestinal microflora in the murine ileum. This model enables us to study specifically the local effects of radiation therapy. Method A midline laparotomy was performed in male C57/Bl6 mice and a five-centimetre segment of ileum is irradiated using the chamber. Leucocyte responses (rolling and adhesion were then analysed in ileal venules 2 – 48 hours after high dose irradiation, made possible by an inverted approach using intravital fluorescence microscopy. Furthermore, intestinal microflora, myeloperoxidase (MPO and cell histology were analysed. Results The highest and most reproducible increase in leucocyte rolling was exhibited 2 hours after high dose irradiation whereas leucocyte adhesion was greatest after 16 hours. Radiation reduced the intestinal microflora count compared to sham animals with a significant decrease in the aerobic count after 2 hours of radiation. Further, the total aerobic counts, Enterobacteriaceae and Lactobacillus decreased significantly after 16 hours. In the radiation groups, the bacterial count showed a progressive increase from 2 to 24 hours after radiation. Conclusion This study presents a refinement of a previous method of examining mechanisms of radiation enteropathy, and a new approach at investigating radiation induced leucocyte responses in the ileal microcirculation. Radiation induced maximum leucocyte rolling at 2 hours and adhesion peaked at 16 hours. It also reduces the microflora count, which then starts to increase steadily afterwards. This model may be instrumental in developing strategies against pathological

  9. The increase in leucocyte count during menstruation is a function of ...

    African Journals Online (AJOL)

    Menstruation is an endocrine mediated physiologic cyclical bleeding per vagina in a non-pregnant woman of the reproductive age group. Blood is a good culture medium for bacteria and as such, menstruation can affect leucocytes count. This study is aimed at evaluating leucocytes count during menstruation. Fifty-eight ...

  10. Comparative test on nuclide migration in aerated zone

    International Nuclear Information System (INIS)

    Li Shushen; Zhao Yingjie; Wu Qinghua; Wang Zhiming; Hao Janzhong; Ji Shaowei; Guo Liangtian; Guo Zhiming

    2002-01-01

    In order to study the influence of different tracer source layer material on nuclide migration behavior, the comparative test on stable elements Sr, Nd and Ce migration in aerated loess zone was carried out using loess and arenaceous quartz as the tracer source layer materials respectively. The test lasted 470 days. During the test, four times of sampling were done. The testing results indicate that under artificial sprinkling of 5 mm/h and 3 h/d, Nd and Ce not only in loess tracer source layer but also in arenaceous quartz tracer source layer did not obviously downwards migrated. Concentration peak of Sr for loess layer migrated down about 15 cm in 470 d (mass center moved down about 10 cm) but for arenaceous quartz layer the concentration peak of Sr did not obviously migrated down (mass center moved down about 2.7 cm). The test results show that very thin arenaceous quartz layer with thickness of 7 mm is also able to shield unsaturated water flow obviously. This is the main reason why the nuclides in arenaceous quartz layer migrate down slowly

  11. Leucocyte count in young adults with first-ever ischaemic stroke: associated factors and association on prognosis.

    Science.gov (United States)

    Heikinheimo, Terttu; Putaala, Jukka; Haapaniemi, Elena; Kaste, Markku; Tatlisumak, Turgut

    2015-02-01

    Limited data exist on the associated factors and correlation of leucocyte count to outcome in young adults with first-ever ischaemic stroke. Our objectives were to investigate factors associated with elevated leucocyte count and whether there is correlation between leucocyte count and short- and long-term outcomes. Of our database of 1008 consecutive patients aged 15 to 49, we included those with leucocyte count measured within the first two days from stroke onset. Outcomes were three-month and long-term disability, death, and vascular events. Linear regression was used to explore baseline variables associated with leucocyte count. Logistic regression and Cox proportional models studied the association between leucocyte count and clinical outcomes. In our study cohort of 781 patients (61.7% males; mean age 41.4 years), mean leucocyte count was high: 8.8 ± 3.1 × 10(9) cells/L (Reference range: 3.4-8.2 × 10(9) cells/L). Higher leucocyte levels were associated with dyslipidaemia, smoking, peripheral arterial disease, stroke severity, and lesion size. After adjustment for age, gender, relevant risk factors, both continuous leucocyte count and the highest quartile of leucocyte count were independently associated with unfavourable three-month outcome. Regarding events in the long-term (follow-up 8.1 ± 4.2 years in survivors), no association between leucocyte count and the event risks appeared. Among young stroke patients, high leucocyte count was a common finding. It was associated with vascular disease and its risk factors as well as severity of stroke, but it was also independently associated with unfavourable three-month outcome in these patients. There was no association with the long-term outcome. [Correction added on 31 October 2013 after first online publication: In the Results section of the Abstract, the cohort of 797 patients in this study was corrected to 781 patients.]. © 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.

  12. Underground radionuclide migration at the Nevada Test Site

    International Nuclear Information System (INIS)

    Nimz, G.J.; Thompson, J.L.

    1992-01-01

    This document reviews results from a number of studies concerning underground migration of radionuclides from nuclear test cavities at the Nevada Test Site (NTS). Discussed are all cases known to the Department of Energy's Hydrology and Radionuclide Migration Program where radionuclides have been detected outside of the immediate vicinity of nuclear test cavities that are identifiable as the-source of the nuclides, as well as cases where radionuclides might have been expected and were intentionally sought but not fixed. There are nine locations where source-identifiable radionuclide migration has been detected, one where migration was purposely induced by pumping, and three where migration might be expected but was not found. In five of the nine cases of non-induced migration, the inferred migration mechanism is prompt fracture injection during detonation. In the other four cases, the inferred migration mechanism is water movement. In only a few of the reviewed cases can the actual migration mechanism be stated with confidence, and the attempt has been made to indicate the level of confidence for each case. References are cited where more information may be obtained. As an aid to future study, this document concludes with a brief discussion of the aspects of radionuclide migration that, as the present review indicates, are not yet understood. A course of action is suggested that would produce a better understanding of the phenomenon of radionuclide migration

  13. Studies on the pathogensis of fever. IX. The production of endogenous pyrogen by polymorphonuclear leucocytes.

    Science.gov (United States)

    KAISER, H K; WOOD, W B

    1962-01-01

    Determination of the dose-response curve for rabbit leucocytic pyrogen reveals a hyperthermic "ceiling" at which there is a marked insensitivity to dosage. This finding has important implications in relation to the quantitative assay of leucocytic pyrogen. Polymorphonuclear leucocytes separated from normal rabbit blood possess the capacity to produce less than 5 per cent of the pyrogen generated by the same number of rabbit granulocytes collected from acute peritoneal exudates. Blood granulocytes, separated in the cold from the buffy coat, contain no detectable preformed pyrogen. The amount of preformed pyrogen within exudate granulocytes represents but a small fraction of the pyrogen which the cells are capable of generating when incubated in normal saline at 37 degrees C. It is suggested that the active pyrogen is formed from an inactive precursor within the cells. Under the conditions tested, cell fragments of rabbit granulocytes fail to produce endogenous pyrogen. The fact that the production of pyrogen is blocked at 4 degrees C is in keeping with the hypothesis that it involves metabolic reactions within the cell.

  14. Testing for 'threads' and leucocyte esterase in first-void urine to exclude the diagnosis of non-specific urethritis in asymptomatic men.

    Science.gov (United States)

    Pallawela, Sanjeeva N S; Sonnex, Christopher; Burdett, Julia; Cooper, Dawn; Nethercott, Katrina; Thomas, Catherina M; Goon, Peter; Webb, Hayley; Carne, Christopher

    2014-07-01

    Recent evidence suggests that asymptomatic nonspecific urethritis (NSU), which is not routinely tested for, is a clinically significant pathology.The aim of this pilot study was to determine if testing for urinary threads, leucocyte esterase (LE) or both in asymptomatic men is a good screening tool for NSU. Of the126 asymptomatic men, 8% met microscopic criteria for the diagnosis of NSU. The positive predictive value for NSU was 71% (95% confidence interval (CI): 29.3-95.5%) and the negative predictive value was 96% (95% CI: 92.8-99.5%). The absence of threads and negative LE makes urethritis highly unlikely, making urinary chlamydia (Chlamydia trachomatis) and gonorrhoea (Neisseria gonorrhoeae) testing sufficient. Incidental findings of further pathology occurred in 7%.

  15. Diagnosis of pyogenic pelvic inflammatory diseases by {sup 99m}Tc-HMPAO leucocyte scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Rachinsky, I.; Boguslavsky, L.; Golan, H.; Lantsberg, S. [Department of Nuclear Medicine, Ben-Gurion Univ. of the Negev (Israel); Goldstein, D.; Pak, I.; Katz, M. [Department of Obstetrics and Gynecology, Ben-Gurion Univ. of the Negev, Beer-Sheva (Israel)

    2000-12-01

    Pelvic inflammatory disease (PID) is one of the major health problems of women of child-bearing age. Among the most serious complications of PID is the formation of a tubo-ovarian abscess (TOA). Early diagnosis of this condition may prevent serious surgical complications such as peritonitis and sepsis, which may be fatal. The purpose of this study was to investigate the efficacy of technetium-99m hexamethylpropylene amine oxime (HMPAO) leucocyte scintigraphy in the diagnosis of TOA. Twenty women with high clinical suspicion of TOA underwent {sup 99m}Tc-HMPAO leucocyte scintigraphy. The labelling of leucocytes with {sup 99m}Tc-HMPAO was performed according to a standard protocol. Scans were obtained at 1, 3 and 24 h following the injection of the labelled leucocytes. In eight cases the early and/or late scan was positive, in 11 cases it was negative, and in one case of ovarian cyst torsion, confirmed by laparoscopy, it showed slight uptake in the capsule of the cyst (false-positive). The sensitivity of {sup 99m}Tc-HMPAO leucocyte scintigraphy was 100%, specificity 91.6%, positive predictive value 89%, negative predictive value 100% and overall accuracy 95%. It is concluded that leucocyte scintigraphy is a non-invasive, safe, physiological and accurate procedure for the diagnosis of TOA. The 24-h scan is crucial, since in some cases the abscess was not clearly visualized on the early scan. Leucocyte scintigraphy may reduce the need for CT, diagnostic laparoscopy and unnecessary invasive surgical procedures. (orig.)

  16. Measurement of specific [3H]-ouabain binding to different types of human leucocytes

    DEFF Research Database (Denmark)

    Boon, Arnold; Oh, V M; Taylor, John E.

    1984-01-01

    We have studied the specific binding of [3H]-ouabain to intact mononuclear leucocytes (82% lymphocytes) and polymorphonuclear leucocytes. In both types of cells [3H]-ouabain binding was saturable, confined to a single site of high affinity, slow to reach equilibrium, slow to reverse, temperature...... were expressed per square micron of cell surface area the difference between the two cell types was proportionately greater (83 and 186 sites per micron 2 respectively). We conclude that the [3H]-ouabain binding sites on mononuclear and polymorphonuclear leucocytes are similar in nature, but different...

  17. The effect of in vitro procedures on cyclic AMP accumulation in human leucocytes

    DEFF Research Database (Denmark)

    Johansen, Torben; Friis, U G; Rasmussen, A K

    1994-01-01

    The aim of this study was to investigate the effect of various methodological procedures or protocols on cyclic AMP formation in human leucocytes. The data showed that: (1) ATP content and lactate production was unaffected by hypotonic lysis during leucocyte isolation; (2) there was a linear rela...

  18. Differential effect of extracellular calcium on the Na(+)-K+ pump activity in intact polymorphonuclear leucocytes and erythrocytes

    DEFF Research Database (Denmark)

    Petersen, R H; Knudsen, T; Johansen, Torben

    1991-01-01

    The effect of extracellular calcium on the Na(+)-K+ pump activity in human polymorphonuclear leucocytes and erythrocytes was studied and compared with the activity in mixed peritoneal leucocytes from rats. While there was maximal decrease in the pump activity (25-30%) of leucocytes from both rat ...

  19. Calcein AM release-based cytotoxic cell assay for fish leucocytes.

    Science.gov (United States)

    Iwanowicz, Luke R; Densmore, Christine L; Ottinger, Christopher A

    2004-02-01

    A non-specific cytotoxic cell assay for fish is presented that is based on the release of the activated fluorochrome calcein AM from lysed carp epithelioma papulosum cyprini (EPC) cells. To establish the suitability of treating EPC cells with calcein AM the uptake and spontaneous release of the calcein AM by the EPC cells was evaluated. Incubation of 5 microM calcein AM in culture medium with 1x10(5)EPC cells well(-1)for a minimum of 3 h provided sufficient labelling. Spontaneous release of fluorescence from the labelled EPC cells during 10 h of post labelling incubation ranged from 30 to 39% of the total observed fluorescence. Cytotoxic activity of trout leucocytes was evaluated at three leucocyte to target cell ratios (10:1, 2:1 and 1:1) following incubation (4, 6, 8, and 10 h) with calcein AM-labelled EPC cells at 15 degrees C. In some instances, the monoclonal antibody specific for the NCC surface receptor NCCRP-1 (MAb5C.6) was included in the cultures. The activity of NCC cells was significantly inhibited in the presence of 0.25 microg well(-1)of MAb5C.6 relative to no antibody (Pleucocyte to target cell ratios. Percent cytotoxic cell activity using calcein AM was similar to values reported for rainbow trout leucocytes using the 51Cr-release assay.

  20. Field tests on migration of TRU-nuclide, (1). General introduction

    International Nuclear Information System (INIS)

    Ogawa, Hiromichi; Tanaka, Tadao; Mukai, Masayuki

    2003-01-01

    The field migration test using TRU nuclide was carried out as a cooperative research project between JAERI (Japan Atomic Energy Research Institute) and CIRP (China Institute for Radiation Protection). This report introduced the out-line of the field migration test and described the outline of the series of 'Field Test on Migration of TRU-nuclide' and main results as a summary report. (author)

  1. Studies on the pathogenesis of fever. III. The leucocytic origin of endogenous pyrogen in acute inflammatory exudates.

    Science.gov (United States)

    KING, M K; WOOD, W B

    1958-02-01

    The evolution of an acute inflammatory exudate produced in rabbits by the intraperitoneal injection of saline has been described. Evidence has been presented that polymorphonuclear leucocytes release endogenous pyrogen into the cell-free fluid of the exudate. Leucocytes from such exudates have also been shown to release pyrogen into the surrounding medium during incubation in vitro at 37 degrees C. The results of parallel cytological studies have provided evidence which suggests that the leucocytes give up their pyrogen while functionally intact. These observations add further support to the hypothesis that polymorphonuclear leucocytes play a significant role in the pathogenesis of fever.

  2. Pulmonary dynamics of radiolabelled erythrocytes and leucocytes in early gram-negative sepsis in pigs

    International Nuclear Information System (INIS)

    Walther, Sten; Wenyao, Shi; Lennquist, Sten

    1999-01-01

    objective: to study the pulmonary dynamic of erythrocytes and leucocytes in vivo in early experimental sepsis. design: open, experimental study. setting: academic research laboratory, Sweden. material: 10 adolescent, domestic pigs. interventions: technetium (Tc 99) labelling of erythrocytes (n=5) and indium (In 111) labelling of autologous leucocytes (n=10). sepsis was induced by endotoxin (n=4) or live Escherichia Coli (n=3), given intravenously. major outcome measures: regional pulmonary scintigraphy, central haemodynamics and gas exchange followed for 180 minutes. results: septic animals developed arterial hypoxia, pulmonary hypertension and systemic hypotension. They also had an early increase in mean (SD) regional pulmonary erythrocyte and leucocyte counts (+10.3(7.7%) and + 12.0 (3.5%) respectively) with simultaneous maximum 27-32 minutes after the start of the septic insult. Conclusions: The immediate sepsis-induced pulmonary accumulation of leucocytes as detected by external scintigraphy can be ascribed at least in part, to a simultaneous sepsis-induced increase in pulmonary blood volume. 3 figs., 1 tab., 19 refs

  3. Using Virtual ATE Model to Migrate Test Programs

    Institute of Scientific and Technical Information of China (English)

    王晓明; 杨乔林

    1995-01-01

    Bacause of high development costs of IC (Integrated Circuit)test programs,recycling existing test programs from one kind of ATE (Automatic Test Equipment) to another or generating directly from CAD simulation modules to ATE is more and more valuable.In this paper,a new approach to migrating test programs is presented.A virtual ATE model based on object-oriented paradigm is developed;it runs Test C++ (an intermediate test control language) programs and TeIF(Test Inftermediate Format-an intermediate pattern),migrates test programs among three kinds of ATE (Ando DIC8032,Schlumberger S15 and GenRad 1732) and generates test patterns from two kinds of CAD 9Daisy and Panda) automatically.

  4. Probabilistic income-maximizing behavior in regional migration: an empirical test.

    Science.gov (United States)

    Weinstein, R I; Evans, R D

    1980-01-01

    "This paper provides an empirical test of the hypothesis that migrants consider income risk in their evaluation of the returns to migration in that higher levels of income risk for a given region reduce the rate of net migration into that region." Theoretical approaches to the incorporation of income risk in migration models are first considered, and alternative approaches are then tested using data on white and nonwhite net migration in the United States between 1960 and 1970. The results indicate support for the hypothesis that the extent of net migration is inversely affected by income risk. excerpt

  5. Leucocyte Response In Nigerian Indigenous Dogs With Surgically ...

    African Journals Online (AJOL)

    ... such as cardiopulmonary and coronary artery bypass are known to trigger an inflammatory response, leading to the activation of leucocytes, platelets and endothelial cells (Asimakopoulos and Taylor, 1998; Asimakopoulos et al., 2000; Ngaage, 2003).Major surgeries reportedly also produce PMNL (neutrophil) dysfunction ...

  6. Involvement of leucocyte/endothelial cell interactions in anorexia nervosa.

    Science.gov (United States)

    Víctor, Víctor M; Rovira-Llopis, Susana; Saiz-Alarcón, Vanessa; Sangüesa, Maria C; Rojo-Bofill, Luis; Bañuls, Celia; de Pablo, Carmen; Álvarez, Ángeles; Rojo, Luis; Rocha, Milagros; Hernández-Mijares, Antonio

    2015-07-01

    Anorexia nervosa is a common psychiatric disorder in adolescence and is related to cardiovascular complications. Our aim was to study the effect of anorexia nervosa on metabolic parameters, leucocyte-endothelium interactions, adhesion molecules and proinflammatory cytokines. This multicentre, cross-sectional, case-control study employed a population of 24 anorexic female patients and 36 controls. We evaluated anthropometric and metabolic parameters, interactions between leucocytes polymorphonuclear neutrophils (PMN) and human umbilical vein endothelial cells (HUVEC), proinflammatory cytokines such as tumour necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) and soluble cellular adhesion molecules (CAMs) including E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1). Anorexia nervosa was related to a decrease in weight, body mass index, waist circumference, systolic blood pressure, glucose, insulin and HOMA-IR, and an increase in HDL cholesterol. These effects disappeared after adjusting for BMI. Anorexia nervosa induced a decrease in PMN rolling velocity and an increase in PMN rolling flux and PMN adhesion. Increases in IL-6 and TNF-α and adhesion molecule VCAM-1 were also observed. This study supports the hypothesis of an association between anorexia nervosa, inflammation and the induction of leucocyte-endothelium interactions. These findings may explain, in part at least, the increased risk of vascular disease among patients with anorexia nervosa. © 2015 Stichting European Society for Clinical Investigation Journal Foundation.

  7. Automated processing of leucocyte-poor platelet concentrates.

    Science.gov (United States)

    Tandy, N P; Seghatchian, M J; Bessos, H

    1992-10-01

    In view of transfusion reactions and alloimmunization associated with leucocyte contamination of platelet concentrates (PC), there is a general move towards the production of leuco-poor PC. This goal is currently pursued by the production of various PC using buffy coat and apheresis techniques. Although there is no overall consensus on the meaning of 'leuco-poor', by assuming that this refers to a level of 5-50 x 10(7) leucocytes per PC, we were able to make comparisons with available systems used in Europe. In addition to platelet and white cell counts, other markers of PC quality were assessed in some cases. These included traditional markers (such as hypotonic stress response, pH, and lactate and beta-thromboglobulin levels) and newer markers (such as glycocalicin and plasma von Willebrand factor levels). Our preliminary results showed appreciable differences in platelet and white cell content of PC prepared by various types of apheresis equipment. Appreciable differences in the quality of stored PC were also observed between routine PC (non-leuco-poor and buffy coat and apheresed PC (leuco-poor).

  8. Field testing at the Climax Stock on the Nevada Test Site: spent fuel test and radionuclide migration experiments

    International Nuclear Information System (INIS)

    Ballou, L.B.; Isherwood, D.J.; Patrick, W.C.

    1982-01-01

    Two field tests in the Climax Stock are being conducted. The Climax Stock, a granitic instrusive, has been administratively excluded from consideration as a full-scale repository site. However, it provides a readily available facility for field testing with high-level radioactive materials at a depth (420 m) approaching that of a repository. The major test activity in the 1980 fiscal year has been initiation of the Spent Fuel Test-Climax (SFT-C). This test, which was authorized in June 1978, is designed to evaluate the generic feasibility of geologic storage and retrievability of commercial power reactor spent fuel assemblies in a granitic medium. In addition, the test is configured and instrumented to provide thermal and thermomechanical response data that will be relevant to the design of a repository in hard crystalline rock. The other field activity in the Climax Stock is a radionuclide migration test. It combines a series of field and laboratory migration experiments with the use of existing hydrologic models for pretest predictions and data interpretation. Goals of this project are to develop: (1) field measurement techniques for radionuclide migration studies in a hydrologic regime where the controlling mechanism is fracture permeability; (2) field test data on radionuclide migration; and (3) a comparison of laboratory- and field-measured retardation factors. This radionuclide migration test, which was authorized in the middle of the 1980 fiscal year, is in the preliminary design phase. The detailed program plan was prepared and subjected to formal peer review in August. In September/October researchers conducted preliminary flow tests with water in selected near-vertical fractures intersected by small horizontal boreholes. These tests were needed to establish the range of pressures, flow rates, and other operating parameters to be used in conducting the nuclide migration tests. 21 references, 14 figures, 1 table

  9. Leucocyte Function in Protein Deficiency States | Wolfsdorf | South ...

    African Journals Online (AJOL)

    No difference in leucocyte counts could be demonstrated between the groups; however, both groups of malnourished patients (groups ll and lll) had elevated NBT levels, although no difference could be detected between those malnourished infants with and without clinical or laboratory evidence of infection, or both.

  10. Radioisotope methods for leucocyte labelling

    International Nuclear Information System (INIS)

    Kostadinova, I.; Kovacheva, S.

    1988-01-01

    A review is made of the labelling methods with the following tracers: 3 H-thymidine, 32 P-DP, 111 In (oxine, tropolon, acetylacetone, MERC), 99m Tc (reduced 99m Tc, lypophyl 99m Tc-complexes and 99m Tc-colloids). The main diagnosis areas are mentioned: abdominal abscesses and inflammations, inflammation foci of skeleton or of implanted prosthesis; acute myocardial infarction, bacterial endocarditis, rejection of kydney transplantations or vascular grafts. It is concluded that labelled leucocytes are very reliable for noninvasive diagnosis of inflammation foci with unclear localization

  11. Brine migration test for Asse Mine, Federal Republic of Germany: final test plan

    International Nuclear Information System (INIS)

    1983-07-01

    The United States and the Federal Republic of Germany (FRG) will conduct a brine migration test in the Asse Salt Mine in the FRG as part of the US/FRG Cooperative Radioactive Waste Management Agreement. Two sets of two tests each will be conducted to study both liquid inclusion migration and vapor migration in the two salt types chosen for the experiments: (1) pure salt, for its characteristics similar to the salt that might occur in potential US repositories, and (2) transitional salt, for its similarity to the salt that might occur in potential repositories in Germany

  12. Evaluation of droplet digital PCR for quantification of residual leucocytes in red blood cell concentrates.

    Science.gov (United States)

    Doescher, A; Loges, U; Petershofen, E K; Müller, T H

    2017-11-01

    Enumeration of residual white blood cells in leucoreduced blood components is essential part of quality control. Digital PCR has substantially facilitated quantitative PCR and was thus evaluated for measurements of leucocytes. Target for quantification of leucocytes by digital droplet PCR was the blood group gene RHCE. The SPEF1 gene was added as internal control for the entire assay starting with automated DNA extraction. The sensitivity of the method was determined by serial dilutions of standard samples. Quality control samples were analysed within 24 h, 7 days and 6 months after collection. Routine samples from leucodepleted red blood cell concentrates (n = 150) were evaluated in parallel by flow-cytometry (LeucoCount) and by digital PCR. Digital PCR reliably detected at least 0·4 leucocytes per assay. The mean difference between PCR and flow-cytometric results from 150 units was -0·01 (±1·0). DNA samples were stable for up to at least six months. PCR measurement of leucocytes in samples from plasma and platelet concentrates also provided valid results in a pilot study. Droplet digital PCR to enumerate leucocytes offers an alternative for quality control of leucoreduced blood products. Sensitivity, specificity and reproducibility are comparable to flow-cytometry. The option to collect samples over an extended period of time and the automatization introduce attractive features for routine quality control. © 2017 International Society of Blood Transfusion.

  13. Study on the chloride migration coefficient obtained following different Rapid Chloride Migration (RCM) test guidelines

    NARCIS (Netherlands)

    Spiesz, P.R.; Brouwers, H.J.H.; Uzoegbo, H.C.; Schmidt, W.

    2013-01-01

    This work presents the differences in the available Rapid Chloride Migration (RCM) test guidelines, and their influence on the values of the chloride migration coefficients DRCM, obtained following these guidelines. It is shown that the differences between the guidelines are significant and concern

  14. Is there a role for Tc-99m HMPAO leucocyte scintigraphy in patients with infective endocarditis?

    International Nuclear Information System (INIS)

    Ellmann, A.; Rubow, S.M.; Erlank, P.; Reuter, H.

    2002-01-01

    Aim: Infective endocarditis is still an important disease in developing countries. Due to the difficult diagnosis, treatment is often delayed or inappropriate. A combination of clinical findings and echocardiography are used most often, but have a low sensitivity. As Tc-99m HMPAO labelled leucocyte scintigraphy is used routinely to evaluate patients with suspected infectious processes, it was postulated that this technique may also aid in the diagnosis of acute infective endocarditis in patients with rheumatic heart disease. Materials and Methods: Six patients who presented with clinical signs and symptoms of infective endocarditis, were referred for Tc-99m HMPAO labelled leucocyte scintigraphy. The white blood cells were labelled according to standard procedures. Whole body planar imaging, and single photon emission tomography of the chest area, with imaging at 30 minutes, 3 hours and 24 hours after the administration of the labelled leucocytes, were performed on all patients. Results: All the scintigrams were negative. No abnormal concentration of leucocytes could be detected in the region of the heart. This was in spite of clinical findings indicative of active infective endocarditis. Conclusion: Vegetations mainly consist of masses of clotted blood and blood cell debris, containing the causative organisms. Leucocytes do not play a major role in the pathologic process. Although only six patients were studied, it appears that Tc-99m HMPAO leucocyte scintigraphy is of no value in the evaluation of patients with infective endocarditis. A study after the administration of radiolabelled antibiotics may be of greater value and should be considered in these patients

  15. Indium-111 labelled leucocyte scintigraphy in the diagnosis of inflammatory disease

    International Nuclear Information System (INIS)

    Roevekamp, M.H.

    1982-01-01

    The purpose of this study was to evaluate the diagnostic usefulness of indium-111 oxinate labelled autologous leucocytes in inflammatory disease. Chapter I provides an outline of the theoretical aspects of leucocyte labelling with indium-111 oxinate, as well as giving a description of the labelling method and scintigraphic technique and of the in-vitro and in-vivo studies performed to evaluate the method. In Chapter II details are given of the initial results obtained in a pilot study. A high false-negative rate led to modification of the labelling technique. The results obtained in patients suspected of intra-abdominal or retroperitoneal located inflammatory lesions are described in Chapter III. Chapter IV contains the description of an indium-111-leucocyte-99mTc-Sn-colloid computer-assisted subtraction technique for a better evaluation of patients suspected of an upper-abdominal inflammatory process. In Chapter V the study performed in patients after arterial reconstructive surgery is described, and the results obtained in patients suspected of an infected orthopaedic prosthesis are given in Chapter VI. Finally the characteristics of the different types of inflammatory responses is reviewed. (Auth.)

  16. Regulation of leucocyte homeostasis in the circulation.

    Science.gov (United States)

    Scheiermann, Christoph; Frenette, Paul S; Hidalgo, Andrés

    2015-08-01

    The functions of blood cells extend well beyond the immune functions of leucocytes or the respiratory and hemostatic functions of erythrocytes and platelets. Seen as a whole, the bloodstream is in charge of nurturing and protecting all organs by carrying a mixture of cell populations in transit from one organ to another. To optimize these functions, evolution has provided blood and the vascular system that carries it with various mechanisms that ensure the appropriate influx and egress of cells into and from the circulation where and when needed. How this homeostatic control of blood is achieved has been the object of study for over a century, and although the major mechanisms that govern it are now fairly well understood, several new concepts and mediators have recently emerged that emphasize the dynamism of this liquid tissue. Here we review old and new concepts that relate to the maintenance and regulation of leucocyte homeostasis in blood and briefly discuss the mechanisms for platelets and red blood cells. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  17. 99Tcsup(m)-HMPAO labelled leucocytes: comparison with 111In-tropolonate labelled granulocytes

    International Nuclear Information System (INIS)

    Peters, A.M.; Roddie, M.E.; Zacharopoulos, G.P.; George, P.; Stuttle, A.W.J.; Lavender, J.P.; Danpure, H.J.; Osman, S.

    1988-01-01

    The lipophilic complex, 99 Tcsup(m)-hexamethylpropyleneamine oxime (HMPAO) is an efficient leucocyte label, and labels granulocytes with more stability than mononuclear leucocytes. The recovery of 99 Tcsup(m)-HMPAO granulocytes was similar to 111 In-labelled granulocytes isolated and labelled in plasma using tropolone. The Tsub(1/2) of 99 Tcsup(m)-HMPAO labelled granulocytes in blood was less than that of 111 In-labelled granulocytes. The initial biodistribution of 99 Tcsup(m)-labelled leucocytes was similar to 111 In-labelled granulocytes, with a rapid initial lung transit, prominent splenic activity, bone marrow activity and minimal hepatic activity, although, unlike 111 In, 99 Tcsup(m) activity was also seen in urine, occasionally in the gallbladder, and, from about 4 h, consistently in the colon. Bone marrow activity was particularly prominent with 99 Tcsup(m). About 6% of 99 Tcsup(m) was excreted in the faeces up to 48 h after injection, and about 17% in urine up to 24 h. The time-activity curves of reticuloendothelial activity up to 24 h were broadly similar for the two labelled cell preparations. Clinical information given by the two agents was similar in 27 of 30 patients who received both. We conclude that with respect to granulocyte kinetics and clinical data, 99 Tcsup(m)-HMPAO labelled leucocytes are comparable with 111 In-tropolonate labelled granulocytes. (author)

  18. Leucocyte profile and offspring production of guinea pig (Cavia cobaya given Anredera cordifolia leaf extract

    Directory of Open Access Journals (Sweden)

    D. Wijayanti

    2018-03-01

    Full Text Available The objective of this study was to determine leucocyte and offspring production of guinea pig (Cavia cobaya giving Anredera cordifolia leaf extract. Materials used were female 16 heads of guinea pig with body weight of 425g. The treatments were an extract of A. cordifolia leaf at doses of 0, 10, 50 and 90 mg/head, designated as T0, T1, T2 and T3, respectively. A. cordifolia leaf extract was administered orally from 10 days prepartum to 10 days postpartum. Blood was taken at 10 days prepartum and 10 days postpartum. Total birth of the offspring was observed. Data were analyzed by analysis of variance and if there was effect of treatment, then continued with Duncan multiple range test and Chi-Square test for fetal production between the given A. cordifolia leaf extract and control. The result showed that there was no significant difference for 10 days prepartum after addition of A cordifolia leaf extract treatment. The postpartum treated showed a total 50 mg/head level increaed for monocytes than that of level 0, 10 and 90 mg/head. Ten days postpartum treatment showed the total increase for leucocyte and monocytes total were 50 and 90 mg/head, respectively compared to 10 mg/head level. Total lymphocyte of 90 mg/head increased compared to level 10 and 50 mg/head. The highest total neutrophil as found at level of 50 mg/head which increased compared to the level of 0 and 10 mg/head. ProvisioningA. cordifolialeaf extract at doses level of 50 and 90 mg/head could increase litter size (P<0.05; χ2=9.267 and decreased offspring mortality (P<0.05; χ2=6.4. In conclusion, by giving 50 mg/head A. cordifolia leaf extract could increase leucocyte profile and offspring production of guinea pig.

  19. Radioisotope methods for leucocyte labelling

    Energy Technology Data Exchange (ETDEWEB)

    Kostadinova, I; Kovacheva, S [Meditsinska Akademiya, Sofia (Bulgaria). Katedra po Rentgenologiya i Radiologiya

    1988-01-01

    A review is made of the labelling methods with the following tracers: {sup 3}H-thymidine, {sup 32}P-DP, {sup 111}In (oxine, tropolon, acetylacetone, MERC), {sup 99m}Tc (reduced {sup 99m}Tc, lypophyl {sup 99m}Tc-complexes and {sup 99m}Tc-colloids). The main diagnosis areas are mentioned: abdominal abscesses and inflammations, inflammation foci of skeleton or of implanted prosthesis; acute myocardial infarction, bacterial endocarditis, rejection of kydney transplantations or vascular grafts. It is concluded that labelled leucocytes are very reliable for noninvasive diagnosis of inflammation foci with unclear localization.

  20. 111In autologous leucocytes in the diagnosis and assessment of inflammatory bowel disease

    International Nuclear Information System (INIS)

    Saverymuttu, S.H.; Peters, A.M.; Reavy, H.J.; Danpure, H.J.; Osman, S.; Chadwick, V.S.; Hodgson, H.J.; Lavender, J.P.

    1982-01-01

    111 In-labelled leucocytes were used to obtain gamma camera images of inflamed of bowel in a wide variety of inflammatory bowel disease. No false positive scans were observed in the irritable bowel syndrome and in bowel malignancy. All patients with moderate or severely active disease had positive scans. Faecal excretion of 111 Indium increased with disease severity. 111 In-tropolone labelling appeared to offer the advantage over 111 In-acac labelling in localising inflamed bowel earlier. In many cases the bowel was imaged within 40 min of re-injection of the leucocytes. 111 In-leucocyte scanning provides a novel approach to the problem of diagnosis and assessment of inflammatory bowel disease. It is non-invasive, requires no bowel preparation and thus is safe in the acutely sick patient where conventional radiological imaging methods may be hazardous. 111 Indium faecal excretion provides an objective assessment of disease activity which should prove useful in evaluating treatment regimes

  1. Response of peripheral leucocytes to whole body irradiation and vitamin E treatment in white leghorn chick

    International Nuclear Information System (INIS)

    Rana, K.; Malhotra, N.

    1993-01-01

    Radiation induced changes in peripheral blood leucocytes in 1 day old male white leghorn chicks were studied after whole body exposure to 2.25 Gy dose of gamma radiation at the rate of 0.50 Gy/sec with and without vitamin E. The changes in total leucocyte counts, lymphocytes and heterophils were observed at 1,3,5,7,14 and 28 days postirradiation. A pronounced leucocytopenia was noted in the initial post-irradiation period. The lymphocytes and heterophils showed a reciprocal relationship after radiation. With vitamin E treatment, considerable and faster recovery was noticed in the leucocytes after irradiation. (author). 16 refs., 3 figs

  2. Analysis of the Rapid Chloride Migration test

    NARCIS (Netherlands)

    Spiesz, P.R.; Ballari, M.; Brouwers, H.J.H.; Ferreira, R. M.; Gulikers, J.; Andrade, C.

    2009-01-01

    In this study the Rapid Chloride Migration test (RCM) standardized as NT Build 492 and BAW-Merkblatt is reviewed. Since the traditional natural diffusion tests are laborious, time consuming and costly, they are not always preferred from a practical point of view. To overcome these disadvantages,

  3. Low leucocyte myeloperoxidase activity in patients with multiple sclerosis

    NARCIS (Netherlands)

    Ramsaransing, G; Teelken, A; Prokopenko, VM; Arutjunyan, AV; De Keyser, J

    The gene for myeloperoxidase (MPO) has been implicated in multiple sclerosis (MS). By measuring H2O2 dependent oxidation of 3,3'5,5'-tetramethylbenzidine with spectrophotometry the authors investigated MPO activity in peripheral blood leucocytes from 42 patients with MS (12 with secondary

  4. Autoradiography and density gradient separation of technetium-99m-Exametazime (HMPAO) labelled leucocytes reveals selectivity for eosinophils

    Energy Technology Data Exchange (ETDEWEB)

    Puncher, M.R.B. [Biological Lab., Univ. of Kent, Canterbury (United Kingdom); Blower, P.J. [Nuclear Medicine Dept., Kent and Canterbury Hospital (United Kingdom)

    1994-11-01

    Technetium-99m-Exametazime (HMPAO) is widely used for radiolabelling leucocytes for localization of infection. The subcellular distribution of radionuclide in the labelled cells and the distribution of radioactivity among the leucocyte population are incompletely understood. Frozen section autoradiography was used to determine quantitatively the distribution of {sup 99m}Tc in leucocytes labelled with {sup 99m}Tc-Exametazime. Sections of rapidly frozen suspensions of labelled leucocytes in plasma were autoradiographed on Ilford K2 emulsion and stained with haematoxylin and eosin. Neutrophils, eosinophils and mononuclear cells were separated by Percoll density gradient centrifugation. Cell nuclei were isolated by a rapid cell-breakage and fractionation method. In a typical experiment mean grain densities [grains/100 {mu}m{sup 2} (ESD)] over cells were: eosinophils 31.2 (18.4), neutrophils 3.5 (3.5), mononuclear cells 4.2 (5.1). Mean grain numbers per cell (ESD) were: eosinophils 13 (6.8), neutrophils 1.3 (1.3), mononuclear cells 1.1 (1.3). These findings were confirmed by separation of labelled leucocytes on discontinuous density gradients. In four separation experiments, the mean activity-per-cell ratio for eosinophils to neutrophils was 10.1 (4.8):1, and for eosinophils to mononuclear cells, 14.1 (6.7):1. The subcellular distribution of the label was investigated using image analysis of autoradiographs and cell fractionation. This revealed no selectivity for nuclear or extranuclear compartments. It may be concluded that {sup 99m}Tc-Exametazime has strong selectivity for eosinophils over other leucocytes but no selectivity for nuclear/cytoplasmic compartments. (orig.)

  5. Clinical application of 99mTc-HMPAO labeled leucocytes imaging in detecting bone joint infection

    International Nuclear Information System (INIS)

    Li Biao; Barthe, N.; Basse-Cathalinat, B.

    1995-01-01

    99m Tc-MDP scintigraphy and 99m Tc-HMPAO-leucocytes imaging were performed in twenty five patients with clinically suspected bone joint infection. All of the 25 cases were confirmed by surgery, microbiological and histologic examinations. Among them 21 cases were definitively diagnosed as infections, while 3 cases were non-infection. The results of 99m Tc-MDP scintigraphy showed that all of 25 cases demonstrated anomalous accumulation of radioactivity in the clinically suspected infections sites, while in 99m Tc-HMPAO-leucocytes imaging, concentrated radioactivity in proved infectious sites was observed in 19 cases, non-anomalous radioactivity found in 4 cases of non-infectious sites, but there were 2 cases false negative with long term antibiotics treatment, none of the case was false positive. Thereby a sensitivity of the labelled leucocytes imaging of 90.5%, a specificity of 100%, and a accuracy of about 92% were found. Present research work concluded that 99m Tc-HMPAO labelled leucocytes imaging provided a non-invasive, effective, and reliable diagnostic method in detecting patients with clinically suspected bone joint infection and afforded strong evidence for effective therapy

  6. Role of IgG4 in histamine release from human basophil leucocytes. I. Sensitization of cells from normal donors

    DEFF Research Database (Denmark)

    Poulsen, L K; Stahl Skov, P; Mosbech, H

    1988-01-01

    Several conflicting reports on the ability of IgG4 to mediate type I allergic reactions have appeared lately. We have developed a model system for testing this possibility, using passive sensitization of basophil leucocytes from normal individuals. At first, the system was optimized with regard t...

  7. Morphological peculiarities of duodenal peptic ulcer and leucocytes functional activity in the persons who were present in the zone of the accident at Chernobyl Atomic Power Station

    International Nuclear Information System (INIS)

    Babak, O.Ya.; Kushnyir, Yi.E.; Bobro, L.M.; Karamishev, D.V.

    1994-01-01

    36 persons with duodenal peptic ulcer (DPU) who were in the zone of the accident at Chernobyl Atomic Power Station (experimental group) and 20 patients who were not exposed to small doses of ionizing radiation were examined to study morphological peculiarities of DPU and blood leucocytes functional activity in the persons who were present in the zone of the accident. The finding have shown that in the persons, exposed to small doses of ionizing radiation, peptic ulcer is often accompanied by erosive changes of gastric and duodenal mucosa. Disturbance of mucus formation in myocytes and secret evacuation from the cells, epithelium large-intestine-type metaplasia, were revealed. Shift of cellular correlation balance in inflammatory infiltrate to the side of monocytes number increase as well as decrease of leucocytes functional activity, manifesting itself by slowing a granulocytes migration to the focus of inflammation, were noted, which is necessary to take into account at administration of effective peptic ulcer therapy in the persons who were in the zone of the accident at Chernobyl Atomic Power Station

  8. Leucocytes labelled with In-111-oxine in acute inflammatory processes

    International Nuclear Information System (INIS)

    Herranz, R.; Lomena, F.; Fernandez, R.M.; Del Rio, L.; Piera, C.; Vida, F.; Setoain, J.

    1982-01-01

    We used autologous leucocytes labelled with In-111-Oxine to diagnose inflammatory processes, located or scattered, in 60 patients. In 46 there was suspected located infection focus. Gammagraphy was abnormal in 38 cases (83%), 28 abdominally located (87%), 5 thorax located (71%) and 5 of several locations. In other 14 cases there was clinic suspicion of infection without located septic focus. In 5 of them gammagraphy was interpreted as positive but only in 3 patients it was found abdominal located abscess. The two other cases are considered as false positive ones. In the 9 remaining, with negative gammagraphy there was no clinic confirmation nor other diagnostic methods of abscess existence. In this paper we checked high sensitivity of leucocytes In-111-Oxine to diagnose and locate infectious focuses. In our casuistry there was only a false negative and two false positive ones

  9. Use of 99mTc-HMPAO-leucocyte scintigraphy coupled to 99mTc-colloid scintigraphy in diagnosing the osteo-articular sepsis

    International Nuclear Information System (INIS)

    Darlas, Y.; Pegoix, M.; Filmont, J.E.; Leclercq, S.; Rosas, M.H.; Agostini, D.; Aubriot, J.H.; Bouvard, G.

    1997-01-01

    The object of this study was the scintigraphic diagnosis of osseous sepsis based on the absence of congruence between leucocytic and colloidal fixations and the evaluation of the effect of coupling between the scintigraphies (sc) with leucocytes (A) and colloids (B) on the diagnosis feasibility index of this technique. Seventy four patients, 97 sc were divided into two groups according to the scintigraphic technique [(A) only]: 35 sc; [(A) and (B)]: 62 sc. [Prosthesis: 48 patients, 68 sc. Osteitis: 26 patients, 29 sc]. The scintigraphies were performed as follows: (A) autologous leucocytes labelled by 250 - 300 MBq of 99m Tc-HMPAO, with planar incidences (15 min), 3 - 4 hours after injection and (B) Labelled nano-colloids labelled by 180 - 200 MBq of 99m Tc, the same incidences, 30 min after injection. The delay between (A) and (B): 48 hours. The final diagnosis of sepsis: bacteriological and histologic criteria after biopsies and/or clinical, biological and radiological evolution. The comparison between the two groups is given in a table in terms of prevalence, sensitivity and specificity, using the χ2 and Fisher tests. In conclusion, the scintigraphy by 99m Tc-HMPAO-leucocyte is a sensitive method (Se ∼ 90%) for the diagnosis of osseous sepsis and coupled to the scintigraphy by 99m Tc-colloids allow obtaining a high specificity (Sp ≥ 90%) by reducing the number of falsely positive diagnoses

  10. Development of lyophilized kit of Tin-Glucoheptonate for in vitro labeling of leucocytes with 99mTc

    International Nuclear Information System (INIS)

    Nascimento, Rosemeire Fagundes

    2007-01-01

    The study and localization of inflammatory and infection process in Nuclear Medicine represents a relevant tool in diagnostic procedures. In same cases, the diagnostic is easy and based on anamnesis and clinical observation; in other cases, the patients are asymptomatic or present non specific symptoms that difficult the diagnostic. The early diagnostic of inflammatory or infectious process allow the early introduction of therapy and prevents complications. Farther, the differentiation between inflammation and infection is of extreme importance as well as the localization of the focus. The use of labeled leucocytes, studied and applied in much pathologies, is the method of choice for the visualization of inflammation and infection. The scintigraphy using labeled leucocytes was introduced at 1976 by McAffe and Thakur and since of this is used in the diagnostic of different pathologies related to leucocyte infiltration like intestinal inflammatory disease, bone or prosthetic-vascular infections. The in vitro labeling of leucocytes with 111 In was performed using oxime or tropolone as ligand and with 99m Tc using hexamethylpropylene amine oxime (HMPAO) as ligand, resulting in a lipophilic complex. The 99m Tc-HMPAG complex was preferably employed in many indications and countries do to the ideal physical properties of 99m Tc that results in low dose to the patient. However, the labeling employing the HMPAO complex results in some disadvantages like the low stability of the complex, and some requirements related to the 99m Tc elution (like the time pos elution), beyond the high cost of the compound that is imported. The aim of this work was the development of a tin-glucoheptonate lyophilized kit for in vitro leucocytes labeling with 99m Tc using the pre-stannization method. The optimization of the labeling technique was developed using leucocytes isolated from total blood and employing different volumes of the tinglucoheptonate reagent and different incubation times at

  11. Clinical experience with 111In tropolonate leucocytes in the detection of occult infection

    International Nuclear Information System (INIS)

    Wraight, E.P.

    1988-01-01

    Over a period of 3 years, 275 scans were performed in 233 patients with suspected occult sepsis. A firm diagnosis was ultimately established in 160 cases. 81 sites of infection were correctly identified and there were 77 true negative studies. There were 4 false negative and 7 false positive studies, most of which were due to misinterpreting bowel activity as sepsis and vice versa. In 56 cases CT scans were performed within a few days of the leucocyte study. There was good agreement between the findings. Comparison was possible with ultrasound in 81 cases. In 15 of these ultrasound failed to detect infection in the abdomen which was demonstrated by 111 In leucocytes, suggesting that ultrasound is much less sensitive in this situation. The overall accuracy of 111 In leucocyte scanning in this series was 93,5%. The predictive value of a positive result was 92% and of a negative one 95%. The need for serial images to distinguish bowel activity (colitis or swallowed activity) from paracolic sepsis is emphasised. (orig.)

  12. Radionuclide migration test using undisturbed aerated soil

    International Nuclear Information System (INIS)

    Yamamoto, Tadatoshi; Ohtsuka, Yoshiro; Ogawa, Hiromichi; Wadachi, Yoshiki

    1988-01-01

    As one of the most important part of safety assessment on the shallow land disposal of lowlevel radioactive waste, the radionuclide migration was studied using undisturbed soil samples, in order to evaluate an exact radionuclide migration in an aerated soil layer. Soil samples used in the migration test were coastal sand and loamy soil which form typical surface soil layers in Japan. The aqueous solution containing 60 CoCl 2 , 85 SrCl 2 and 137 CsCl was fed into the soil column and concentration of each radionuclide both in effluent and in soil was measured. Large amount of radionuclides was adsorbed on the surface of soil column and small amount of radionuclides moved deep into the soil column. Difference in the radionuclide profile was observed in the low concentration portion particularly. It is that some fractions of 60 Co and 137 Cs are stable in non-ionic form and move downward through the soil column together with water. The radionuclide distribution in the surface of soil column can be fairly predicted with a conventional migration equation for ionic radionuclides. As a result of radionuclide adsorption, both aerated soil layers of coastal sand and loamy soil have large barrier ability on the radionuclide migration through the ground. (author)

  13. In vitro effects of prostaglandin E2 on leucocytes from sticklebacks (Gasterosteus aculeatus) infected and not infected with the cestode Schistocephalus solidus.

    Science.gov (United States)

    Kutyrev, Ivan A; Franke, Frederik; Büscher, Janine; Kurtz, Joachim; Scharsack, Jörn P

    2014-12-01

    Many helminth parasites have evolved strategies to evade the immune response of their hosts, which includes immunomodulation. Prostaglandin E2 (PGE2) is one of the best-described immunomodulators in mammalian helminth parasite infections. We hypothesized that also in teleost fish anti-helminthic immune responses are regulated via PGE2. We used a model system consisting of the tapeworm Schistocephalus solidus and its host, the three-spined stickleback (Gasterosteus aculeatus), to investigate in vitro effects of PGE2 on head kidney leucocytes (HKL) derived from sticklebacks that were experimentally infected with S. solidus. PGE2 was tested alone or in combination with either S. solidus antigens or bacterial lipopolysaccharides (LPS). After in vitro culture, cell viability and changes in leucocyte subpopulations (granulocytes to lymphocytes ratios) were monitored by flow cytometry and HKL were tested for their capacity to produce reactive oxygen species (ROS) with a chemiluminescence assay. In short term (2 h) HKL cultures PGE2 did not change the total numbers of live HKL, but the production of ROS decreased significantly with high (0.1 μmol L(-1)) PGE2 concentrations. In long-term (96 h) cultures high PGE2 concentrations induced a sharp decrease of leucocytes viability, while low (0.1 pmol L(-1)) and intermediate (0.1 nmol L(-1)) concentrations of PGE2 caused elevated leucocyte viability compared to controls. This coincided with reduced ROS production in cultures with high PGE2 and elevated ROS production in cultures with low PGE2. Granulocyte to lymphocyte ratios increased with high PGE2 concentrations alone and in combination with S. solidus antigens and LPS, most prominently with HKL from S. solidus infected sticklebacks. The present study supports the hypothesis that PGE2 might be an immunomodulator in tapeworm-fish parasite-host interactions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. FDG and FDG-labelled leucocyte PET/CT in the imaging of prosthetic joint infection

    Energy Technology Data Exchange (ETDEWEB)

    Aksoy, Sabire Yilmaz; Asa, Sertac; Ozhan, Meftune; Sager, M.S.; Halac, Metin; Kabasakal, Levent; Soenmezoglu, Kerim; Kanmaz, Bedii [University of Istanbul, Department of Nuclear Medicine, Cerrahpasa Medical Faculty, Aksaray, Istanbul (Turkey); Ocak, Meltem [University of Istanbul, Department of Pharmaceutical Technology, Faculty of Pharmacy, Istanbul (Turkey); Erkan, Melih Engin [Duzce University School of Medicine, Department of Nuclear Medicine, Duzce (Turkey)

    2014-03-15

    The demand for arthroplasty is rapidly growing as a result of the ageing of the population. Although complications such as heterotrophic ossification, fracture and dislocation are relatively rare, differentiating aseptic loosening, the most common complication of arthroplasty from infection, is a major challenge for clinicians. Radionuclide imaging is currently the imaging modality of choice since it is not affected by orthopaedic hardware. Whereas FDG PET/CT imaging has been widely used in periprosthetic infection, it cannot discriminate aseptic from septic inflammation. In this study we aimed to evaluate the role of FDG PET/CT and FDG-labelled leucocyte PET/CT in the diagnosis of periprosthetic infection. Of 54 patients with painful joint arthroplasty who were imaged by FDG PET/CT for diagnosis of periprosthetic infection examined, 46 (36 women, 10 men; mean age 61.04 ± 12.2 years, range 32 - 89 years) with 54 painful joint prostheses (19 hip, 35 knee) with grade 2 (above liver uptake) FDG accumulation on FDG PET/CT were included in the study and these 46 patients also underwent FDG-labelled leucocyte PET/CT. Final diagnoses were made by histopathological-microbiological culture or clinical follow-up. The final diagnosis showed infection in 15 (28 %) and aseptic loosening in 39 (72 %) of the 54 prostheses. FDG PET/CT was found to have a positive predictive value of 28 % (15/54). Since patients with no FDG uptake on FDG PET/CT were excluded from the study, the sensitivity, specificity, negative predictive value and accuracy could not be calculated. The sensitivity, specificity, and positive and negative predictive values of FDG-labelled leucocyte PET/CT were 93.3 % (14/15), 97.4 % (38/39), 93.3 % and 97.4 %, respectively. Since FDG is not specific to infection, the specificity of FDG PET/CT was very low. FDG-labelled leucocyte PET/CT with its high specificity may be a useful method and better than labelled leucocyte scintigraphy in periprosthetic infection

  15. 86Rubidium uptake in mononuclear leucocytes from young subjects at increased risk of developing essential hypertension

    DEFF Research Database (Denmark)

    Nielsen, J R; Johansen, Torben; Pedersen, K E

    1988-01-01

    This study was designed to assess any changes in mononuclear leucocytes from young men at increased risk of developing essential hypertension and to determine whether any changes found were associated with borderline hypertension and/or heredity. To this end we used mononuclear leucocytes......, and especially in those borderline hypertensives with at least one hypertensive parent. The latter group was also the group at greatest risk of developing essential hypertension....

  16. Differential expression of PARP1 mRNA in leucocytes of patients ...

    Indian Academy of Sciences (India)

    P. 2011 Differential expression of PARP1 mRNA in leucocytes of patients with Down's syndrome. J. Genet. ... of Alzheimer disease at an earlier age than subjects with- ... family and personal informed consent. .... In effect, they report that.

  17. Database on gas migration tests through bentonite buffer material

    International Nuclear Information System (INIS)

    Tanai, Kenji

    2009-02-01

    Carbon steel is a candidate material for an overpack for geological disposal of high-level radioactive waste in Japan. The corrosion of the carbon steel overpack in aqueous solution under anoxic conditions will cause the generation of hydrogen gas, which may affect hydrological and mechanical properties of the bentonite buffer. To evaluate such an effect of gas generation, it is necessary to develop a model of gas migration through bentonite buffer material taking account of data obtained from experiments. The gas migration experiments under both unsaturated and saturated conditions have been carried out to clarify the fundamental characteristics of bentonite for gas migration. This report compiles the experimental data obtained from gas migration tests for buffer material which has been conducted by JAEA until December, 2007. A CD-ROM is attached as an appendix. (author)

  18. Tritium migration studies at the Nevada Test Site

    International Nuclear Information System (INIS)

    Schulz, R.K.; Weaver, M.O.

    1993-05-01

    Emanation of tritium from waste containers is a commonly known phenomenon. Release of tritium from buried waste packages was anticipated; therefore, a research program was developed to study both the rate of tritium release from buried containers and subsequent migration of tritium through soil. Migration of tritium away from low-level radioactive wastes buried in Area 5 of the Nevada Test Site was studied. Four distinct disposal events were investigated. The oldest burial event studied was a 1976 emplacement of 3.5 million curies of tritium in a shallow land burial trench. In another event, 248 thousand curies of tritium was disposed of in an overpack emplaced 6 m below the floor of a low-level waste disposal pit. Measurement of the emanation rate of tritium out of 55 gallon drums to the overpack was studied, and an annual doubling of the emanation rate over a seven year period, ending in 1990, was found. In a third study, upward tritium migration in the soil, resulting in releases in the atmosphere were observed in a greater confinement disposal test. Releases of tritium to the atmosphere were found to be insignificant. The fourth event consisted of burial of 2.2 million curies of tritium in a greater confinement disposal operation. Emanation of tritium from the buried containers has been increasing since disposal, but no significant migration was found four years following backfilling of the disposal hole

  19. /sup 99/Tcsup(m)-HMPAO labelled leucocytes: comparison with /sup 111/In-tropolonate labelled granulocytes

    Energy Technology Data Exchange (ETDEWEB)

    Peters, A.M.; Roddie, M.E.; Zacharopoulos, G.P.; George, P.; Stuttle, A.W.J.; Lavender, J.P.; Danpure, H.J.; Osman, S.

    1988-06-01

    The lipophilic complex, /sup 99/Tcsup(m)-hexamethylpropyleneamine oxime (HMPAO) is an efficient leucocyte label, and labels granulocytes with more stability than mononuclear leucocytes. The recovery of /sup 99/Tcsup(m)-HMPAO granulocytes was similar to /sup 111/In-labelled granulocytes isolated and labelled in plasma using tropolone. The Tsub(1/2) of /sup 99/Tcsup(m)-HMPAO labelled granulocytes in blood was less than that of /sup 111/In-labelled granulocytes. The initial biodistribution of /sup 99/Tcsup(m)-labelled leucocytes was similar to /sup 111/In-labelled granulocytes, with a rapid initial lung transit, prominent splenic activity, bone marrow activity and minimal hepatic activity, although, unlike /sup 111/In, /sup 99/Tcsup(m) activity was also seen in urine, occasionally in the gallbladder, and, from about 4 h, consistently in the colon. Bone marrow activity was particularly prominent with /sup 99/Tcsup(m). About 6% of /sup 99/Tcsup(m) was excreted in the faeces up to 48 h after injection, and about 17% in urine up to 24 h. The time-activity curves of reticuloendothelial activity up to 24 h were broadly similar for the two labelled cell preparations. Clinical information given by the two agents was similar in 27 of 30 patients who received both. We conclude that with respect to granulocyte kinetics and clinical data, /sup 99/Tcsup(m)-HMPAO labelled leucocytes are comparable with /sup 111/In-tropolonate labelled granulocytes.

  20. Indium 111 leucocyte scintigraphy in abdominal sepsis

    International Nuclear Information System (INIS)

    Baba, A.A.; McKillop, J.H.; Gray, H.W.; Cuthbert, G.F.; Neilson, W.; Anderson, J.R.

    1990-01-01

    We have studied the clinical utility of indium 111 autologous leucocyte scintigraphy retrospectively in 45 patients presenting with suspected intra-abdominal sepsis. The sensitivity was 95% (21/22) and the specificity was 91% (21/23). Some 34 of the studies (17 positive and 17 negative) were considered helpful in furthering patient management (76%) and 8, unhelpful (18%). In 3, the study results were misleading and led to inappropriate treatment. Indium 111 scintigraphy, whether positive or negative, provides information in patients with suspected intra-abdominal sepsis upon which therapeutic decisions can be based. (orig.)

  1. Possibilities for prognostication of radiation injury in rats by leucocyte nucleic acid levels

    International Nuclear Information System (INIS)

    Minkova, M.; Pantev, T.

    1988-01-01

    The possibilities to prognosticate acute radiation injury by the changes in the amount of nucleic acids in the leucocytes was studied. Experiments were carried out on male Wistar albino rats, gamma-irradiated with nonlethal and sublethal doses of 0.5, 2 and 4 Gy and lethal dose of 8 Gy (LD 90/30 ). The nucleic acid content and the total leucocyte count were determined at definite intervals on days 1-30. The changes in the nucleic acids in nonlethally and sublethally irradiated animals had phase nature, with a clear-cut abortive increase in their amount on days 7-10. In lethally irradiated animals the phase character of the changes was lost and the abortive peak disappeared. By reducing the effectiveness of the lethal radiation dose survival of the population increased from 10-75% through physical and from 10-70% - through chemical protection. The nucleic acid dynamics showed features typical for an injury with possible survival - appearance of abortive peak and resumption of their normal values. It is assumed that determination of leucocyte nucleic acid content may be used for early prognostication of radiation injury, as it allows keen differentiation of the lethal from nonlethal outcome of radiation sickness. The absence of abortive peak (over 50%) by day 14 post-irradiation is a poor prognostic sign

  2. Elastolytic activity of human blood monocytes characterized by a new monoclonal antibody against human leucocyte elastase. Relationship to rheumatoid arthritis

    DEFF Research Database (Denmark)

    Jensen, H S; Christensen, L D

    1990-01-01

    The leucocyte elastase of human blood monocytes was investigated by applying a new monoclonal antibody which did not block the enzyme activity against elastin. In a fixed population of mononuclear cells (MNC) and using fluorescence activated cell sorting (FACS), the human leucocyte elastase (HLE...

  3. The diagnostic accuracy of the rapid dipstick test to predict asymptomatic urinary tract infection of pregnancy.

    Science.gov (United States)

    Eigbefoh, J O; Isabu, P; Okpere, E; Abebe, J

    2008-07-01

    Untreated urinary tract infection can have devastating maternal and neonatal effects. Thus, routine screening for bacteriuria is advocated. This study was designed to evaluate the diagnostic accuracy of the rapid dipstick test to predict urinary tract infection in pregnancy with the gold standard of urine microscopy, culture and sensitivity acting as the control. The urine dipstick test uses the leucocyte esterase, nitrite and test for protein singly and in combination. The result of the dipstick was compared with the gold standard, urine microscopy, culture and sensitivity using confidence interval for proportions. The reliability and validity of the urine dipstick was also evaluated. Overall, the urine dipstick test has a poor correlation with urine culture (p = 0.125, CI 95%). The same holds true for individual components of the dipstick test. The overall sensitivity of the urine dipstick test was poor at 2.3%. Individual sensitivity of the various components varied between 9.1% for leucocyte esterase and the nitrite test to 56.8% for leucocyte esterase alone. The other components of the dipstick test, the test of nitrite, test for protein and combination of the test (leucocyte esterase, nitrite and proteinuria) appear to decrease the sensitivity of the leucocyte esterase test alone. The ability of the urine dipstick test to correctly rule out urinary tract infection (specificity) was high. The positive predictive value for the dipstick test was high, with the leucocyte esterase test having the highest positive predictive value compared with the other components of the dipstick test. The negative predictive value (NPV) was expectedly highest for the leucocyte esterase test alone with values higher than the other components of the urine dipstick test singly and in various combinations. Compared with the other parameters of the urine dipstick test, singly and in combination, leucocyte esterase appears to be the most accurate (90.25%). The dipstick test has a

  4. New bis(dithiocarboxylato)nitridotechnetium-99m radiopharmaceuticals for leucocyte labelling: In vitro and in vivo studies

    Energy Technology Data Exchange (ETDEWEB)

    Demaimay, F.; Noiret, N.; Roucoux, A. E-mail: Alain.Roucoux@univ-Rennes1.Fr; Patin, H.; Bellande, E.; Pasqualini, R.; Moisan, A

    1997-07-01

    Dithiocarboxylate ligands were synthesized and characterized. New nitrido 99m-technetium complexes were obtained with these ligands and identified by thin layer chromatography. The nitrido complexes were tested in vitro in whole blood for leucocyte labelling and the design of the ligand was optimized. Best results were obtained with aliphatic linear ligands, containing 9 to 11 atoms of carbon. The in vivo experiment failed because an inflammated area could not be visualized by {gamma} imaging, the cell labelling mechanism being probably different.

  5. New bis(dithiocarboxylato)nitridotechnetium-99m radiopharmaceuticals for leucocyte labelling: In vitro and in vivo studies

    International Nuclear Information System (INIS)

    Demaimay, F.; Noiret, N.; Roucoux, A.; Patin, H.; Bellande, E.; Pasqualini, R.; Moisan, A.

    1997-01-01

    Dithiocarboxylate ligands were synthesized and characterized. New nitrido 99m-technetium complexes were obtained with these ligands and identified by thin layer chromatography. The nitrido complexes were tested in vitro in whole blood for leucocyte labelling and the design of the ligand was optimized. Best results were obtained with aliphatic linear ligands, containing 9 to 11 atoms of carbon. The in vivo experiment failed because an inflammated area could not be visualized by γ imaging, the cell labelling mechanism being probably different

  6. The predictive value of leucocyte progression for one-week mortality on acutely admitted medical patients to the emergency department

    DEFF Research Database (Denmark)

    Brabrand, Mikkel; Soltau, Matilde Røgilds

    2018-01-01

    female. Using logistic regression, we found significantly lower one-week mortality with falling leucocyte count progression, even when controlling for confounders. A decreasing leucocyte count had a sensitivity for one-week mortality of 65%, specificity of 62%, positive predictive value of 4......%, and negative predictive value of 99%. Difference in admission to the intensive care unit was non-significant between the three groups. Difference in length of stay was significant, but with one day difference, the clinical significance is questionable. CONCLUSION: Leucocyte count progression is not sensitive...... enough to predict one-week mortality, nor specific enough to discount it. It is important for physicians to be aware of this to avoid faulty assessments based on imprecise assumptions....

  7. Nightly Test system migration

    CERN Document Server

    Win-Lime, Kevin

    2013-01-01

    The summer student program allows students to participate to the Cern adventure. They can follow several interesting lectures about particle science and participate to the experiment work. As a summer student, I had worked for LHCb experiment. LHCb uses a lot of software to analyze its data. All this software is organized in packages and projects. They are built and tested during the night using an automated system and the results are displayed on a web interface. Actually, LHCb is changing this system. It is looking for a replacement candidate. So I was charged to unify some internal interfaces to permit a swift migration. In this document, I will describe shortly the system used by LHCb, then I will explain what I have done in detail.

  8. Social and environmental factors modulate leucocyte profiles in free-living Greylag geese (Anser anser

    Directory of Open Access Journals (Sweden)

    Didone Frigerio

    2017-01-01

    Full Text Available Background Blood parameters such as haematocrit or leucocyte counts are indicators of immune status and health, which can be affected, in a complex way, by exogenous as well as endogenous factors. Additionally, social context is known to be among the most potent stressors in group living individuals, therefore potentially influencing haematological parameters. However, with few exceptions, this potential causal relationship received only moderate scientific attention. Methods In a free-living and individually marked population of the highly social and long-lived Greylag goose, Anser anser, we relate variation in haematocrit (HCT, heterophils to lymphocytes ratio (H/L and blood leucocyte counts to the following factors: intrinsic (sex, age, raising condition, i.e. goose- or hand-raised, social (pair-bond status, pair-bond duration and parental experience and environmental (biologically relevant periods, ambient temperature factors. Blood samples were collected repeatedly from a total of 105 focal birds during three biologically relevant seasons (winter flock, mating season, summer. Results We found significant relationships between haematological parameters and social as well as environmental factors. During the mating season, unpaired individuals had higher HCT compared to paired and family individuals and this pattern reversed in fall. Similarly, H/L ratio was positively related to pair-bond status in a seasonally dependent way, with highest values during mating and successful pairs had higher H/L ratio than unsuccessful ones. Also, absolute number of leucocytes tended to vary depending on raising condition in a seasonally dependent way. Discussion Haematology bears a great potential in ecological and behavioural studies on wild vertebrates. In sum, we found that HTC, H/L ratio and absolute number of leucocytes are modulated by social factors and conclude that they may be considered valid indicators of individual stress load.

  9. Sub-Microscopic Organization and Functional Properties of Cells Stored in a Bank for Frozen Leucocytes and Platelets

    Energy Technology Data Exchange (ETDEWEB)

    Vinograd-Finkel, F. R.; Terentieva, E. I.; Leontovich, V. A.; Skopina, S. B.; Abezgauz, N. N.; Totskaya, A. A. [Central Institute of Haematology and Blood Transfusion, Moscow, USSR (Russian Federation)

    1969-07-15

    Massive transfusions of leucocyte mass containing young and stem cells in addition to adult cells are carried out successfully in the treatment of patients suffering from depressed haemopoiesis. To meet the needs of clinics a leucocyte mass bank-has been established and methods have been developed for the long-term storage of leucocyte mass by keeping it in the frozen state at -196 Degree-Sign C. Various carrier solutions containing cryoprotective substances (dimethylsulphoxide, glycerine, polyvinyl pyrrolidone) have been proposed. These make it possible to conserve from 70 to 90% of live cells for as long as two years or more. The viability of the frozen cells is proved by supravital staining and luminescent microscopy, and also by determining the extent to which their functional properties are preserved, the phagocytic activity of the granulocytes and the ability of the lymphocytes to produce young forms in tissue culture. It has also been observed that their glycolytic activity is preserved (up to 60%). All these data correlate with the data obtained by electron microscopy regarding the extent to which the sub-microscopic organization of frozen leucocytes is preserved. The bank is also used to store a frozen platelet mass, dimethylsulphoxide being used as the cryoprotective agent. The ultrastructure of the platelets and their functional properties (retractile activity) suffer least impairment. (author)

  10. Effects of gamma-irradiation of plastics on migration of constituents into test foods

    International Nuclear Information System (INIS)

    Figge, K.; Freytag, W.

    1977-01-01

    Test films prepared from polyethylene (LD- and HD-PE), polypropylene (PP), polystyrene (St- and HI-PS) and polyvinylchloride (rigid PVC) compositions under addition of 2,6-di-tert-butyl-4-methyl[ 14 C]-phenol(I), 3-(3,5-di-tert-butyl -4-hydroxyphenyl)- stearyl-propionate[3- 14 C] (II), n-butyl-stearate[1- 14 C] (III) di-n-octyl[1- 14 C]-tin-2 -ethyl-hexyl-di-thioglycolate inclusive of the corresponding mono-n-octyl[1- 14 C]-tin compound (IV-Oc), di-n-octyl-tin-2-ethylhexyl -di-thioglycolate[2- 14 C] inclusive of the corresponding 2-ethylhexyl-tri -thioglycolate[2- 14 C] (IV-S) or of stearyl alcohol [1- 14 C] (V) respectively, were sterilized in a 60 Co irradiation unit with a radiation dosage of 2,5 Mrad. Then, the irradiated films as well as non-treated reference films were kept in one-sided contact with the test foodstuffs 'dist. Water' and HB 307 (test fat) for 10 days at 40 0 C. Under these conditions the additives I and II migrated from the PP, HD-PE and LD-PE test films into the test fat HB 307 in amounts of 10 to 50%. Migration into distilled water was only 0.05 to 4.6%. The migration of the additives I and II from the irradiated polyolefin test films into the test fat HB 307 was by 8 to 38% lower than that from the corresponding non-irradiated films. In contrast to this, both additives migrated distinctly more strongly from the irradiated polyolefin test films into distilled water, i.e. 1.9 to 8.7 times stronger than from the non-irradiated films. The migration of the additives I to V from the HI-PS St-PS and rigid PVC test films into the two test foodstuffs was very low, in most cases below 0.1%. Generally lower amounts of additive migrated from the irradiated films than from the non-irradiated samples. (orig.) [de

  11. Application of the Poisson-Nernst-Planck equations to the migration test

    DEFF Research Database (Denmark)

    Krabbenhøft, Kristian; Krabbenhøft, Jørgen

    2008-01-01

    The Poisson-Nernst-Planck (PNP) equations are applied to model the migration test. A detailed analysis of the equations is presented and the effects of a number of common, simplifying assumptions are quantified. In addition, closed-form solutions for the effective chloride diffusivity based...... on the full PNP equations are derived, a number of experiments are analyzed in detail, and a new, truly accelerated migration test is proposed. Finally, we present a finite element procedure for numerical solution of the PNP equations....

  12. Leucocyte depletion attenuates the early increase in myocardial capillary permeability to small hydrophilic solutes following ischaemia and reperfusion

    DEFF Research Database (Denmark)

    Svendsen, Jesper Hastrup; Hansen, P R; Ali, S

    1993-01-01

    The aim was to assess the significance of polymorphonuclear leucocytes on the myocardial capillary permeability to a small hydrophilic indicator, on the vascular tone of the resistance vessels, and on contractile function following ischaemia and reperfusion.......The aim was to assess the significance of polymorphonuclear leucocytes on the myocardial capillary permeability to a small hydrophilic indicator, on the vascular tone of the resistance vessels, and on contractile function following ischaemia and reperfusion....

  13. Effects of dietary n-3 fatty acids on Toll-like receptor activation in primary leucocytes from Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Arnemo, Marianne; Kavaliauskis, Arturas; Andresen, Adriana Magalhaes Santos; Bou, Marta; Berge, Gerd Marit; Ruyter, Bente; Gjøen, Tor

    2017-08-01

    The shortage of the n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the international markets has led to increasing substitution of fish oil by plant oils in Atlantic salmon (Salmo salar) feed and thereby reducing the EPA and DHA content in salmon. However, the minimum required levels of these fatty acids in fish diets for securing fish health are unknown. Fish were fed with 0, 1 or 2% EPA or DHA alone or in combination of both over a period, growing from 50 to 400 g. Primary head kidney leucocytes were isolated and stimulated with Toll-like receptor (TLR) ligands to determine if EPA and DHA deficiency can affect expression of important immune genes and eicosanoid production. Several genes related to viral immune response did not vary between groups. However, there was a tendency that the high-level EPA and DHA groups expressed lower levels of IL-1β in non-stimulated leucocytes. These leucocytes were also more responsive to the TLR ligands, inducing higher expression levels of IL-1β and Mx1 after stimulation. The levels of prostaglandin E2 and leukotriene B4 in serum and media from stimulated leucocytes were lower in both low and high EPA and DHA groups. In conclusion, leucocytes from low EPA and DHA groups seemed to be less responsive towards immunostimulants, like TLR ligands, indicating that low levels or absence of dietary EPA and DHA may have immunosuppressive effects.

  14. Plan and progress of a cooperative research program on field migration test between CIRP and JAERI

    International Nuclear Information System (INIS)

    Li Shushen; Wang Zhiming; Li Zhentang

    1999-01-01

    As the main parts of a cooperative research project on safety assessment method for shallow land disposal of low level radioactive wastes between the China Institute for radiation Protection (CIRP) and the Japan Atomic Energy Research Institute (JAERI), field migration tests investigating the migration of radionuclides 90 Sr, 237 Np and 238 Pu and stable elements Sr, Ce, and Nd in both aerated zone and aquifer are carried out. 3 H and Br are used as tracers to obtain the water flow velocity in the aquifer and the movement of moisture water in the aerated zone for radioactive and non-radioactive tests, respectively. The aerated zone migration tests are carried out with media including soil, bentonite, cement block and mortar in both natural rainfall condition and artificial rainfall condition. The aquifer migration tests are carried out with assemblies (Type I), experimental frame (Type II) and injection tube (Type III), respectively, in and Underground Research Facility (URF). The aerated zone migration tests were started in May, 1997, while the aquifer migration tests started in August 1997. (author)

  15. Increased leucocyte Na-K ATPase in obesity: reversal following weight loss

    International Nuclear Information System (INIS)

    Turaihi, K.; Baron, D.N.; Dandona, P.

    1987-01-01

    Ouabain-sensitive 86 Rb influx and [ 3 H] ouabain binding capacity were investigated in the leucocytes of 17 obese patients and 15 control subjects. Both were significantly increased in the obese when compared with controls. Following dietary restriction and a 4% to 5% weight reduction in the obese over 2 weeks, [ 3 H] ouabain binding and ouabain-sensitive 86 Rb influx (a model for K+ influx) decreased to levels similar to those in controls. This shows that the number of Na-K ATPase sites on leucocyte membranes of the obese are significantly increased and that this is associated with accelerated 86 Rb transport. Since both of these indices decreased following 4% to 5% reduction in body weight while the patients were still obese, increased Na-K ATPase is neither a marker of nor cardinal to the pathogenesis of obesity. We conclude that (1) increase in Na-K ATPase units and 86 Rb influx are not characteristic of obesity itself and (2) dietary restriction over the short-term with limited weight reduction restores Na-K ATPase units and 86 Rb influx to normal

  16. Brine migration test - Asse salt mine, Federal Republic of Germany

    International Nuclear Information System (INIS)

    Rothfuchs, T.; Wieczorek, K.; Feddersen, H.K.; Staupendahl, G.; Coyle, A.J.; Kalia, H.; Eckert, J.

    1988-03-01

    This document is the final report on the Cooperative German-American 'Brine Migration Tests' that were performed at the Asse Salt Mine in the Federal Republic of Germany (FRG), the Office of Nuclear Waste Isolation (ONWI), Columbus, Ohio, and the Institut fuer Tieflagerung (IfT), Braunschweig, of the Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen (GSF). Final test and equipment design as well as manufacturing and installation was carried out by Westinghouse Electric Corporation. The tests were designed to simulate a nuclear waste repository to measure the effects of heat and gamma radiation on brine migration, salt decrepitation, disassociation of brine, and gases collected. The thermal mechanical behavior of salt, such as room closure, stresses and changes of the properties of salt are measured and compared with predicted behavior. The performance of an array of candidate waste package materials, test equipment and procedures under repository conditions will be evaluated with a view towards future in-depth testing of potential repository sites. (orig./RB)

  17. DCAF4, a novel gene associated with leucocyte telomere length

    DEFF Research Database (Denmark)

    Mangino, Massimo; Christiansen, Lene; Stone, Rivka

    2015-01-01

    BACKGROUND: Leucocyte telomere length (LTL), which is fashioned by multiple genes, has been linked to a host of human diseases, including sporadic melanoma. A number of genes associated with LTL have already been identified through genome-wide association studies. The main aim of this study was t...

  18. Influence of the applied voltage on the Rapid Chloride Migration (RCM) test

    NARCIS (Netherlands)

    Spiesz, P.R.; Brouwers, H.J.H.

    2012-01-01

    This study addresses the influence of the applied voltage (electrical field) on the value of the chloride migration coefficient, as determined with the Rapid Chloride Migration (RCM) test, and on other properties of cement based mortars. It is shown that in the investigated ranges of applied

  19. In vitro effects of virgin microplastics on fish head-kidney leucocyte activities.

    Science.gov (United States)

    Espinosa, Cristóbal; García Beltrán, José María; Esteban, María Angeles; Cuesta, Alberto

    2018-04-01

    Microplastics are well-documented pollutants in the marine environment that result from production or fragmentation of larger plastic items. The knowledge about the direct effects of microplastics on immunity, including fish, is still very limited. We investigated the in vitro effects of microplastics [polyvinylchloride (PVC) and polyethylene (PE)] on gilthead seabream (Sparus aurata) and European sea bass (Dicentrarchus labrax) head-kidney leucocytes (HKLs). After 1 and 24 h of exposure of HKLs with 0 (control), 1, 10 and 100 mg mL -1 MPs in a rotatory system, cell viability, innate immune parameters (phagocytic, respiratory burst and peroxidase activities) and the expression of genes related to inflammation (il1b), oxidative stress (nrf2, prdx3), metabolism of xenobiotics (cyp1a1, mta) and cell apoptosis (casp3) were studied. Microplastics failed to affect the cell viability of HKLs. In addition, they provoke very few significant effects on the main cellular innate immune activities, as decrease on phagocytosis or increase in the respiratory burst of HKLs with the highest dose of microplastics tested. Furthermore, microplastics failed to affect the expression of the selected genes on sea bass or seabream, except the nrf2 which was up-regulated in seabream HKLs incubated with the highest doses. Present results seem to suggest that continue exposure of fish to PVC or PE microplastics could impair fish immune parameters probably due to the oxidative stress produced in the fish leucocytes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Indium-111-labelled leucocytes for localisation of abscesses

    Energy Technology Data Exchange (ETDEWEB)

    Segal, A W; Thakur, M L; Arnot, R N; Lavender, J P [Royal Postgraduate Medical School, London (UK)

    1976-11-13

    Leucocytes from eight patients who were thought to have an abscess were labelled with indium-111 and reintroduced into the circulation. The distribution of radioactivity was followed by whole-body scanning and imaging with a gamma camera. Focal accumulations of radioactivity were observed in the lesion in the three patients with abscesses, in the lungs of a boy with bacterial endocarditis, in the knee of a woman with rheumatoid arthritis, and at the site of intramuscular injections in another patient. The use of radiolabelled cells for the detection of focal pathological processes would seem to be an important addition to conventional diagnostic methods.

  1. Analysis of the theoretical model of the rapid chloride migration test

    NARCIS (Netherlands)

    Spiesz, P.; Brouwers, H.J.H.; Fisher, Gregor; Geiker, Metta Rica; Hededal, Ole; Ottosen, Lisbeth M.; Stang, Henrik

    2010-01-01

    Chloride ion diffusion coefficient in concrete is estimated very often by using electromigration tests, among which the Rapid Chloride Migration (RCM) test is becoming more and more popular. Nevertheless, this test receives much criticism due to lacks in its scientific background. In this paper the

  2. A study on the equivalence of olive oil and the EU official substitute test media for migration testing at high temperatures.

    Science.gov (United States)

    Alnafouri, A J; Franz, R

    1999-10-01

    As a consequence of an increasing awareness and findings about the technical and analytical difficulties related to the employment of triglycerides as fatty food simulants in migration testing, EU Directive 82/711/EEC on the basic rules of migration has been amended for the second time and adapted with the recent Commission Directive 97/48/EC. The major merit of this important amendment is to authorize alternative tests such as extraction tests and to allow substitute tests for the fat test with concrete indication of corresponding test conditions to be applied. As a novelty in food law compliance testing it authorizes a modified polyphenylene oxide (MPPO), well-known as Tenax, a thermostable and highly adsorptive porous polymer, as a 'solid' matrix to substitute fat simulant D at temperatures equal to or higher than 100 degrees C. In the study presented here, comparative migration testing--overall and specific--was carried out between fat simulants olive oil and 14C-labelled HB 307 and the substitute test media iso-octane, 95% ethanol and MPPO using polypropylene materials as examples at test temperatures of 100 degrees C to 120 degrees C and prescribed corresponding substitute test conditions. As a consequence, a number of conclusions were drawn which are relevant for overall and/or specific migration testing under the investigated test conditions. One of the major findings was that MPPO was generally more equivalent to the fat test than the other two substitute test media. The presence of volatile hydrocarbons in the test samples was found to play a crucial role with respect to the equivalence of the iso-octane-based substitute test. At high volatile concentrations in the test sample the iso-octane test underestimated the olive oil benchmark whereas low volatile concentrations led to satisfying equivalence. It is therefore recommended that the procedure is modified and GC-FID screening of the isooctane extract is carried out. As a logical consequence, the

  3. THE STUDY OF GAS MIGRATION IN CRYSTALLINE ROCK USING INJECTION TESTS

    Directory of Open Access Journals (Sweden)

    Jiří Svoboda

    2012-07-01

    Full Text Available The study of gas migration in crystalline rock using injection tests is being carried out in the frame of the FORGE (Fate of Repository Gases project. The Czech Technical University in Prague (CTU, Centre of Experimental Geotechnics (CEG is participating in WP4 which is focused on disturbed host rock formations with respect to radioactive waste deep repositories. A series of in-situ tests is being conducted at the Josef Underground Laboratory. The aim of the testing is to simulate and study phenomena that might lead to gas-driven radionuclide transport in fractured crystalline rock. The in-situ tests combine migration and large-scale gas injection measurements; gas injection tests are being employed for the study of gas transport. For the purposes of comparison of the behaviour of the rock mass with regard to air and water a series of water pressure tests are also being carried out. The quality of the rock mass is assessed using rock mass classification systems.

  4. Polymorphonuclear leucocytes consume oxygen in sputum from chronic Pseudomonas aeruginosa pneumonia in cystic fibrosis

    DEFF Research Database (Denmark)

    Kolpen, Mette; Hansen, C. R.; Bjarnsholt, Thomas

    2010-01-01

    BACKGROUND: Chronic lung infection with Pseudomonas aeruginosa is the most severe complication for patients with cystic fibrosis (CF). This infection is characterised by endobronchial mucoid biofilms surrounded by numerous polymorphonuclear leucocytes (PMNs). The mucoid phenotype offers protection...

  5. Increased leucocyte Na-K ATPase in obesity: reversal following weight loss

    Energy Technology Data Exchange (ETDEWEB)

    Turaihi, K.; Baron, D.N.; Dandona, P.

    1987-09-01

    Ouabain-sensitive /sup 86/Rb influx and (/sup 3/H) ouabain binding capacity were investigated in the leucocytes of 17 obese patients and 15 control subjects. Both were significantly increased in the obese when compared with controls. Following dietary restriction and a 4% to 5% weight reduction in the obese over 2 weeks, (/sup 3/H) ouabain binding and ouabain-sensitive /sup 86/Rb influx (a model for K+ influx) decreased to levels similar to those in controls. This shows that the number of Na-K ATPase sites on leucocyte membranes of the obese are significantly increased and that this is associated with accelerated /sup 86/Rb transport. Since both of these indices decreased following 4% to 5% reduction in body weight while the patients were still obese, increased Na-K ATPase is neither a marker of nor cardinal to the pathogenesis of obesity. We conclude that (1) increase in Na-K ATPase units and /sup 86/Rb influx are not characteristic of obesity itself and (2) dietary restriction over the short-term with limited weight reduction restores Na-K ATPase units and /sup 86/Rb influx to normal.

  6. Visualization of inflammatory processes using 'in vitro' and in vivo' labelled leucocytes

    International Nuclear Information System (INIS)

    Kostadinova, I.; Milanov, S.; Kovacheva, S.

    1993-01-01

    The labelled leucocytes have become a means of choice for the diagnosis of a variety of active inflammatory conditions. The aim of the study was to evaluate 'in vivo' and 'in vitro' methods for labelling of leucocytes. A total of 146 patients, suspected of having various inflammatory lesions were examined. In 95 of them 'in vitro' method with 99m Tc-HMPAO or 111 In-oxine was used, in 29 'in vivo' method with 99m Tc-MAB (BW 250/183) and in 22 both methods. The obtained results of sensitivity, specificity and accuracy were 87,3%, 96,5%, 89,5% for 'in vitro' method and 83,3%, 93,8%, 86,2% for 'in vivo' method. Taking into consideration the received data and comparable results, we think that in seriously ill patients and in cases of urgency, the use of easier 'in vivo' method is more suitable, while in chronic processes or in such with unclear localisation, 'in vitro' method is recommended, which sometimes gives images with better quality. (orig.) [de

  7. An Improved method for separation of leucocytes from peripheral blood of the little skate (Leucoraja erinacea)

    Science.gov (United States)

    Tomana, Mitsuru; Parton, Angela; Barnes, David W.

    2008-01-01

    Cartilaginous fish, especially sharks, rays and skates (elasmobranchs) hold interest as comparative models in immunology because they are thought to be among the organisms most closely related to the ancestor animal that first developed acquired immunity. The aim of this study was to improve methods used for the purification of viable leucocytes from peripheral blood of elasmobranchs. Here we describe modifications of density gradient centrifugation and medium formulation that improve isolation and analysis of highly-purified leucocytes from peripheral blood of a model elasmobranch, Leucoraja erinacea, the little skate. These techniques contribute to the preparation of elasmobranch immune cells that can be reliably analyzed by a variety of means, including the study of immune function. PMID:18474431

  8. Large block migration experiments: INTRAVAL phase 1, Test Case 9

    Energy Technology Data Exchange (ETDEWEB)

    Gureghian, A.B.; Noronha, C.J. (Battelle, Willowbrook, IL (USA). Office of Waste Technology Development); Vandergraaf, T.T. (Atomic Energy of Canada Ltd., Ottawa, ON (Canada))

    1990-08-01

    The development of INTRAVAL Test Case 9, as presented in this report, was made possible by a past subsidiary agreement to the bilateral cooperative agreement between the US Department of Energy (DOE) and Atomic Energy of Canada Limited (AECL) encompassing various aspects of nuclear waste disposal research. The experimental aspect of this test case, which included a series of laboratory experiments designed to quantify the migration of tracers in a single, natural fracture, was undertaken by AECL. The numerical simulation of the results of these experiments was performed by the Battelle Office of Waste Technology Development (OWTD) by calibrating an in-house analytical code, FRACFLO, which is capable of predicting radionuclide transport in an idealized fractured rock. Three tracer migration experiments were performed, using nonsorbing uranine dye for two of them and sorbing Cs-137 for the third. In addition, separate batch experiments were performed to determine the fracture surface and rock matrix sorption coefficients for Cs-137. The two uranine tracer migration experiment were used to calculate the average fracture aperture and to calibrate the model for the fracture dispersivity and matrix diffusion coefficient. The predictive capability of the model was then tested by simulating the third, Cs-137, tracer test without changing the parameter values determined from the other experiments. Breakthrough curves of both the experimental and numerical results obtained at the outlet face of the fracture are presented for each experiment. The reported spatial concentration profiles for the rock matrix are based solely on numerical predictions. 22 refs., 12 figs., 8 tabs.

  9. Indium-111-labelled leucocytes for localisation of abscesses

    International Nuclear Information System (INIS)

    Segal, A.W.; Thakur, M.L.; Arnot, R.N.; Lavender, J.P.

    1976-01-01

    Leucocytes from eight patients who were thought to have an abscess were labelled with indium-111 and reintroduced into the circulation. The distribution of radioactivity was followed by whole-body scanning and imaging with a gamma camera. Focal accumulations of radioactivity were observed in the lesion in the three patients with abscesses, in the lungs of a boy with bacterial endocarditis, in the knee of a woman with rheumatoid arthritis, and at the site of intramuscular injections in another patient. The use of radiolabelled cells for the detection of focal pathological processes would seem to be an important addition to conventional diagnostic methods. (author)

  10. Reprogramming neutral lipid metabolism in mouse dendritic leucocytes hosting live Leishmania amazonensis amastigotes.

    Directory of Open Access Journals (Sweden)

    Hervé Lecoeur

    Full Text Available BACKGROUND: After loading with live Leishmania (L amazonensis amastigotes, mouse myeloid dendritic leucocytes/DLs are known to undergo reprogramming of their immune functions. In the study reported here, we investigated whether the presence of live L. amazonensis amastigotes in mouse bone marrow-derived DLs is able to trigger re-programming of DL lipid, and particularly neutral lipid metabolism. METHODOLOGY/PRINCIPAL FINDINGS: Affymetrix-based transcriptional profiles were determined in C57BL/6 and DBA/2 mouse bone marrow-derived DLs that had been sorted from cultures exposed or not to live L. amazonensis amastigotes. This showed that live amastigote-hosting DLs exhibited a coordinated increase in: (i long-chain fatty acids (LCFA and cholesterol uptake/transport, (ii LCFA and cholesterol (re-esterification to triacyl-sn-glycerol (TAG and cholesteryl esters (CE, respectively. As these neutral lipids are known to make up the lipid body (LB core, oleic acid was added to DL cultures and LB accumulation was compared in live amastigote-hosting versus amastigote-free DLs by epi-fluorescence and transmission electron microscopy. This showed that LBs were both significantly larger and more numerous in live amastigote-hosting mouse dendritic leucocytes. Moreover, many of the larger LB showed intimate contact with the membrane of the parasitophorous vacuoles hosting the live L. amazonensis amastigotes. CONCLUSIONS/SIGNIFICANCE: As leucocyte LBs are known to be more than simple neutral lipid repositories, we set about addressing two related questions. Could LBs provide lipids to live amastigotes hosted within the DL parasitophorous vacuole and also deliver? Could LBs impact either directly or indirectly on the persistence of L. amazonensis amastigotes in rodent skin?

  11. Studies on the pathogenesis of fever. IV. The site of action of leucocytic and circulating endogenous pyrogen.

    Science.gov (United States)

    KING, M K; WOOD, W B

    1958-02-01

    By means of a method designed to compare the febrile responses produced by intracarotid and intravenous injections, the endogenous pyrogen, which is contained in leucocytic exudates and is present in the serum of rabbits 2 hours after intravenous injections of typhoid vaccine, has been shown to act directly upon the thermoregulatory centers of the brain. In contrast, the exogenous bacterial pyrogen present in serum obtained 5 minutes after vaccine injections was found to act by a different and less direct mechanism. These observations add strong support to the original hypothesis that endogenous pyrogen, presumably derived from polymorphonuclear leucocytes, is an essential factor in the pathogenesis of endotoxin fever.

  12. Radionuclide migration studies at the Nevada Test Site

    International Nuclear Information System (INIS)

    Thompson, J.L.

    1989-01-01

    The United States government routinely tests nuclear devices at the Nevada Test Site (NTS) in southern Nevada. A significant amount of radioactive material exists underground at the NTS with no containers or engineered barriers to inhibit its subsequent migration. The Department of Energy has sponsored for many years a research program on radionuclide movement in the geologic media at this location. Goals of this research program are to measure the extent of movement of radionuclides away from underground explosion sites and to determine the mechanisms by which such movement occurs. This program has acquired significance in another aspect of nuclear waste management because of the Yucca Mountain Project. Yucca Mountain at the NTS is being intensively studied as the possible site for a mined repository for high level nuclear waste. The NTS provides a unique setting for field studies concerning radionuclide migration; there is the potential for greatly increasing our knowledge of the behavior of radioactive materials in volcanogenic media. This review summarizes some of the significant findings made under this research program at the NTS and identifies reports in which the details of the research may be found. 36 refs., 4 figs

  13. Modulation of cytokine release by differentiated CACO-2 cells in a compartmentalized coculture model with mononuclear leucocytes and nonpathogenic bacteria

    DEFF Research Database (Denmark)

    Parlesak, Alexandr; Haller, D.; Brinz, S.

    2004-01-01

    To further investigate the interaction between human mononuclear leucocytes [peripheral blood mononuclear cells (PBMC)] and enterocytes, the effect of a confluent layer of differentiated CACO-2 cells on cytokine kinetics during challenge with bacteria in a compartmentalized coculture model...... cells when leucocytes were stimulated directly with bacteria. This suppression was not paralleled by changes in the production of IL-10, IL-6 and transforming growth factor (TGF)-beta. When the bacteria were applied apically to the CACO-2 cell layer, the production of TNF-alpha, IL-12, IL-1beta, IL-8......, IL-6, IL-10, TGF-beta and interferon-gamma was pronouncedly lower as compared to the bacterial stimulation of leucocytes beneath the CACO-2 cells. In the latter experiments, IL-6, IL-8 and TNF-alpha were the cytokines being mostly induced by apical addition of E. coli. Quantitative mRNA expression...

  14. Randomised comparison of leucocyte-depleted versus buffy-coat-poor blood transfusion and complications after colorectal surgery

    DEFF Research Database (Denmark)

    Jensen, L S; Kissmeyer-Nielsen, P; Wolff, B

    1996-01-01

    BACKGROUND: Allogeneic blood transfusion is associated with an increased frequency of postoperative infection. We studied whether such events can be avoided by the intraoperative and postoperative use of leucocyte-depleted blood. METHODS: 589 consecutive patients scheduled for elective colorectal...... surgery were randomised to receive buffy-coat poor (n = 299) or filtered leucocyte-depleted red-cells (n = 290) when transfusion was indicated. 260 patients actually received blood transfusion. Three patients were excluded from analysis. FINDINGS: The 142 patients randomised to and transfused with buffy......-coat-poor blood had a significantly higher frequency of wound infections and intra-abdominal abscesses than the 155 patients who were allocated to this group but who were not transfused. (12 vs 1%, p blood also had a significantly...

  15. Radionuclide migration experiments related to an underground nuclear test: II. modeling studies

    International Nuclear Information System (INIS)

    Tompson, A.; Carle, S.F.; Smith, D.K.; Hudson, G.B.; Bruton, C.J.

    2001-01-01

    Full text: The goal of this project is to improve our understanding of water and radionuclide migration in both saturated and unsaturated geologic media by coupling advanced simulation techniques, available characterization data, and radioanalytical measurements in the context of a remarkable field experiment. Between 1975 and 1991, groundwater was steadily pumped from a well adjacent to a 1965 underground test conducted in alluvium at the Nevada Test Site. The experiment was primarily conducted in order to elicit information on radionuclide migration through the saturated zone between the test and the well. The effluent was monitored. discharged to an unlined ditch, and allowed to infiltrate into the ground during flow towards a dry lake, about a kilometer away. The 16 years of pumping and infiltration created an unexpected second experiment in which the migration of the ditch effluent through the 200 meters of unsaturated media, back to the water table, could be studied. Pumping and effluent data are being utilized in conjunction with chemical measurements made in groundwater and a series of numerical models to better understand the movement of radionuclides in the system, both between the test and the well, and between the ditch and the water table. The release of radionuclides away from a testing area will be controlled by local groundwater flow rates, by their dissolution from solidified melt glass produced by the test, and by chemical sorption processes that retard their migration rates in chemically reactive geologic media. Only the more mobile and less reactive radionuclides (e.g.. tritium, 14 C, 36 Cl, 85 Kr, and 129 I) were measured in the well effluent. The movement of these radionuclides through the unsaturated media beneath the ditch will be affected additionally by the capillary nature of moisture movement under unsaturated conditions and by their interaction with and potential mass exchange with the gas (air) phase. Results of numerical simulations

  16. A possible role for polymorphonuclear leucocytes in the defence against recrudescent herpes simplex virus infection in man

    International Nuclear Information System (INIS)

    Russell, A.S.; Miller, C.

    1978-01-01

    A 51 Cr release assay has been used to demonstrate that human polymorphonuclear leucocytes (PMNL) can damage herpes simplex infected target cells sensitized with antiviral antibody. Effective sensitizing antibodies were found in both serum and saliva of all those persons tested who were subject to recurrent cold sores. PMNL were much less effective as killer cells than peripheral blood mononuclear cells, but as they are the predominant inflammatory cell within the HSVl lesion they may be, quantitatively, more important. The cytotoxic effects of both PMNL and mononuclear cells were significantly reduced by prostaglandin El as well as by several drugs that were tested. It is suggested that antibody dependent PMNL-mediated cytotoxicity may play a role in the human host defences against recrudescent herpes simplex infection. (author)

  17. Platelet-, leucocyte- and red cell-derived microparticles in stored whole blood, with and without leucofiltration, with and without ionising radiation.

    Science.gov (United States)

    Saito, Shunnichi; Nollet, Kenneth E; Ngoma, Alain M; Ono, Takako; Ohto, Hitoshi

    2018-02-01

    Storage lesion, including microparticle formation, has been partially characterised in whole blood, but not in all combinations of pre-storage leucofiltration and/or irradiation. Single-donor whole blood products were processed into four subunits: with and without leucofiltration, with and without X-irradiation (25 Gy). Platelet-, leucocyte-, and erythrocyte-derived microparticles and free haemoglobin were measured periodically throughout 42 days of storage. Pre-storage leucofiltration substantially reduced platelet- and leucocyte-derived microparticle counts throughout storage. Irradiation, in contrast, had no significant effect on microparticle counts. A gate for all microparticles showed a substantial time-dependent increase in unfiltered whole blood. A time-dependent increase in free haemoglobin was greatest in unfiltered, irradiated whole blood. This study indicates that leucofiltration can prevent the formation of leucocyte- and platelet-derived microparticles, and might reduce haemolysis in irradiated whole blood, either by removing factors that provoke haemolysis, or by selective retention of senescent or effete red cells most prone to haemolysis.

  18. Effects of 131I therapy on blood borne leucocytes in hyperthyroid patients

    International Nuclear Information System (INIS)

    Lundell, G.

    1975-01-01

    The different types of circulating leucocytes were examined in 54 patients before and 2 to 4 months after 131 I therapy for hyperthyroidism. An absolute and differential percentage increase in the number of juvenile segmented neutrophils, eosinophilic and basophilic granulocytes was demonstrated in the patients free from signs of hyperthyroidism after therapy. This increase was statistically significant. No changes occurred in the 11 patients remaining hyperthyroid. (author)

  19. Labelling of leucocytes with colloidal technetium-99m-SnF2: an investigation of the labelling process by autoradiography

    International Nuclear Information System (INIS)

    Puncher, M.R.B.; Blower, P.J.

    1995-01-01

    Autoradiography of smears and frozen sections of labelled cell suspensions was used to study the distribution of radioactivity in and among blood cells labelled in either whole blood or leucocyte-rich plasma (LRP) with technetium-99m-SnF 2 colloid. The tracer proved selective for neutrophils: the labelling probability (relative to that for erythrocytes) for each cell type in LRP (mean of five samples) was: neutrophils, 9.4; lymphocytes, 3.7; monocytes, 3.0; eosinophils 1.4; erythrocytes, 1.0. When labelling was carried out in whole blood (five samples), 74.5%±8.3% of the cell-bound radioactivity was bound to erythrocytes, 13.6%±6.5% to neutrophils, and 11.9%±2.1% to lymphocytes, whereas in LRP (in which the leucocytes were only slightly outnumbered by erythrocytes), 76.5%±14.9% of radioactivity was neutrophil bound. Labelled cells in smear autoradiographs exhibited two distinct silver grain patterns, ''diffuse'', consistent with an intracellular radioactive particle (in neutrophils), and ''focal'', consistent with a cell surface-adhering particle in direct contact with the emulsion (in other leucocyte types and erythrocytes). The phagocytic inhibitor cytochalasin B neither reduced the proportion of labelled neutrophils nor altered the labelling pattern. Neutrophils were able to scavenge radioactivity from the surface of erythrocytes. It is concluded that neutrophils bind 99m Tc-SnF 2 intracellularly by phagocytosis, with high affinity; other cells become labelled at the cell surface reversibly and with lower affinity. This selectivity is high enough to permit predominantly leucocyte labelling in LRP but not in whole blood. (orig.)

  20. Testing nano-silver food packaging to evaluate silver migration and food spoilage bacteria on chicken meat.

    Science.gov (United States)

    Gallocchio, Federica; Cibin, Veronica; Biancotto, Giancarlo; Roccato, Anna; Muzzolon, Orietta; Carmen, Losasso; Simone, Belluco; Manodori, Laura; Fabrizi, Alberto; Patuzzi, Ilaria; Ricci, Antonia

    2016-06-01

    Migration of nanomaterials from food containers into food is a matter of concern because of the potential risk for exposed consumers. The aims of this study were to evaluate silver migration from a commercially available food packaging containing silver nanoparticles into a real food matrix (chicken meat) under plausible domestic storage conditions and to test the contribution of such packaging to limit food spoilage bacteria proliferation. Chemical analysis revealed the absence of silver in chicken meatballs under the experimental conditions in compliance with current European Union legislation, which establishes a maximum level of 0.010 mg kg(-1) for the migration of non-authorised substances through a functional barrier (Commission Regulation (EU) No. 10/2011). On the other hand, microbiological tests (total microbial count, Pseudomonas spp. and Enterobacteriaceae) showed no relevant difference in the tested bacteria levels between meatballs stored in silver-nanoparticle plastic bags or control bags. This study shows the importance of testing food packaging not only to verify potential silver migration as an indicator of potential nanoparticle migration, but also to evaluate the benefits in terms of food preservation so as to avoid unjustified usage of silver nanoparticles and possible negative impacts on the environment.

  1. Leucocyte depletion in a drowning victim during rewarming with extracorporeal circulation may limit pulmonary oedema

    NARCIS (Netherlands)

    Vermeijden, Wytze J.; de Vries, Hans; Kieboom, Joke; Waterbolk, Tjalling

    2006-01-01

    We report two drowning victims with hypothermic circulatory arrest who were resuscitated with the use of extracorporeal circulation (ECC). The first patient developed severe post-bypass pulmonary oedema and inspired us to use a leucocyte-depletion filter in the second patient to attenuate

  2. Leucocytes Mutation load Declines with Age in Carriers of the m.3243A>G Mutation

    DEFF Research Database (Denmark)

    Langdahl, Jakob Høgild; Larsen, Martin; Frost, Morten

    2018-01-01

    Carriers of the mitochondrial mutation m.3243A>G presents highly variable phenotypes including mitochondrial encephalomyopaty, lactoacidosis and stroke-like episodes (MELAS). We conducted a follow-up study to evaluate changes in leucocyte heteroplasmy and the clinical phenotypes in m.3243A...

  3. Increased glucocerebrosidase (GBA) 2 activity in GBA1 deficient mice brains and in Gaucher leucocytes.

    Science.gov (United States)

    Burke, Derek G; Rahim, Ahad A; Waddington, Simon N; Karlsson, Stefan; Enquist, Ida; Bhatia, Kailash; Mehta, Atul; Vellodi, Ashok; Heales, Simon

    2013-09-01

    Lysosomal glucocerebrosidase (GBA1) deficiency is causative for Gaucher disease. Not all individuals with GBA1 mutations develop neurological involvement raising the possibility that other factors may provide compensatory protection. One factor may be the activity of the non-lysosomal β-glucosidase (GBA2) which exhibits catalytic activity towards glucosylceramide and is reported to be highly expressed in brain tissue. Here, we assessed brain GBA2 enzymatic activity in wild type, heterozygote and GBA1 deficient mice. Additionally, we determined activity in leucocytes obtained from 13 patients with Gaucher disease, 10 patients with enzymology consistent with heterozygote status and 19 controls. For wild type animals, GBA2 accounted for over 85 % of total brain GBA activity and was significantly elevated in GBA1 deficient mice when compared to heterozygote and wild types (GBA1 deficient; 92.4 ± 5.6, heterozygote; 71.5 ± 2.4, wild type 76.8 ± 5.1 nmol/h/mg protein). For the patient samples, five Gaucher patients had GBA2 leucocyte activities markedly greater than controls. No difference in GBA2 activity was apparent between the control and carrier groups. Undetectable GBA2 activity was identified in four leucocyte preparations; one in the control group, two in the carrier group and one from the Gaucher disease group. Work is now required to ascertain whether GBA2 activity is a disease modifying factor in Gaucher disease and to identify the mechanism(s) responsible for triggering increased GBA2 activity in GBA1 deficiency states.

  4. Cetirizine inhibits skin reactions but not mediator release in immediate and developing late-phase allergic cutaneous reactions. A double-blind, placebo-controlled study

    DEFF Research Database (Denmark)

    Nielsen, P N; Skov, P S; Poulsen, Lars K.

    2001-01-01

    Recent reports have indicated cetirizine, a potent H(1)-receptor antagonist, to possess a number of anti-inflammatory effects, e.g. inhibition of mast cell degranulation and inhibition of leucocyte migration and activation.......Recent reports have indicated cetirizine, a potent H(1)-receptor antagonist, to possess a number of anti-inflammatory effects, e.g. inhibition of mast cell degranulation and inhibition of leucocyte migration and activation....

  5. Labelling of leucocytes with colloidal technetium-99m-SnF{sub 2}: an investigation of the labelling process by autoradiography

    Energy Technology Data Exchange (ETDEWEB)

    Puncher, M.R.B. [Biological Lab., Canterbury Univ. (United Kingdom); Blower, P.J. [Nuclear Medicine Dept., Kent and Canterbury Hospital, Canterbury (United Kingdom)

    1995-02-01

    Autoradiography of smears and frozen sections of labelled cell suspensions was used to study the distribution of radioactivity in and among blood cells labelled in either whole blood or leucocyte-rich plasma (LRP) with technetium-99m-SnF{sub 2} colloid. The tracer proved selective for neutrophils: the labelling probability (relative to that for erythrocytes) for each cell type in LRP (mean of five samples) was: neutrophils, 9.4; lymphocytes, 3.7; monocytes, 3.0; eosinophils 1.4; erythrocytes, 1.0. When labelling was carried out in whole blood (five samples), 74.5%{+-}8.3% of the cell-bound radioactivity was bound to erythrocytes, 13.6%{+-}6.5% to neutrophils, and 11.9%{+-}2.1% to lymphocytes, whereas in LRP (in which the leucocytes were only slightly outnumbered by erythrocytes), 76.5%{+-}14.9% of radioactivity was neutrophil bound. Labelled cells in smear autoradiographs exhibited two distinct silver grain patterns, ``diffuse``, consistent with an intracellular radioactive particle (in neutrophils), and ``focal``, consistent with a cell surface-adhering particle in direct contact with the emulsion (in other leucocyte types and erythrocytes). The phagocytic inhibitor cytochalasin B neither reduced the proportion of labelled neutrophils nor altered the labelling pattern. Neutrophils were able to scavenge radioactivity from the surface of erythrocytes. It is concluded that neutrophils bind {sup 99m}Tc-SnF{sub 2} intracellularly by phagocytosis, with high affinity; other cells become labelled at the cell surface reversibly and with lower affinity. This selectivity is high enough to permit predominantly leucocyte labelling in LRP but not in whole blood. (orig.)

  6. The effect of serum from obese and normal weight men on glucose metabolism in leucocytes

    International Nuclear Information System (INIS)

    Myking, O.; Kjoesen, B.; Bassoee, H.H.

    1980-01-01

    The influence of pooled serum from either obese or normal weight males on glucose metabolism in human leucocytes has been studied. Leucocytes from normal weight males were incubated with 10-90% pooled serum and either [U- 14 C], or [1- 14 C]glucose. Compared to serum from the normal weight males, serum from the obese group had a more stimulating effect on the 14 CO 2 and [ 14 C]lactate production from [U- 14 C]glucose and on the 14 CO 2 production from [1- 14 C]glucose. The two serum pools had the same stimulating effect on the Embden-Meyerhof pathway as indicated by the formation of [ 14 C]lactate from [l- 14 C]glucose. Calculations revealed that the activity in the pentose phosphate pathway was stimulated more by serum from obese, than from normal weight males. It is a possibility that increased stimulation of the pentose phosphate pathway may contribute to the development of overweight. (author)

  7. Recommendations for the determination of migration parameters by field experiments (tracer tests)

    International Nuclear Information System (INIS)

    Adam, C.

    1989-01-01

    The hydrogeologic review and assessment of candidate sites for nuclear power plants includes expertises on the potential subsurface migration of radionuclides in the event of accident conditions. To this end, knowledge of representative migration parameters is required. Detailed recommendations are given for determining such parameters by tracer field tests, for using standardized terminology in their practical conduct as well as for interpreting the data obtained. Also, mention has been made of recent work reported by other authors on this topic. 31 refs. (author)

  8. Reactivity of eleven anti-human leucocyte monoclonal antibodies with lymphocytes from several domestic animals

    DEFF Research Database (Denmark)

    Aasted, Bent; Blixenkrone-Møller, Merete; Larsen, Else Bang

    1988-01-01

    Nine commercially available monoclonal antibodies and two monoclonal antibodies from The American Type Culture Collection, raised against various human leucocyte surface antigens, were tested on lymphocytes from cow, sheep, goat, swine, horse, cat, dog, mink, and rabbit as well as man. Four...... antibodies bound to lymphocytes from some of the animals. These were the antibodies against CD8 and CD4 antigen, the antibody to C3b-receptor, and the antibody to the HLA-DR antigen. The CD8 antigen-reactive antibody reacted with lymphocytes from mink, cat, dog, and sheep, while the CD4 antigen......-reactive antibody reacted with lymphocytes from mink. The anti-C3b-R antibody reacted with lymphocytes from horse, swine, dog, and cat, and the anti-HLA-DR reacted with lymphocytes from cow, goat, sheep, horse, dog, cat, and mink....

  9. Diagnosis of gastric carcinoma and precancerosis by leucocyte adherence inhibition RIA(/sup 51/Cr-LAI)

    Energy Technology Data Exchange (ETDEWEB)

    Stosiek, P; Varga, A; Kasper, A; Werner, H

    1982-11-01

    23 patients with gastric cancer, 16 patients with gastric mucosa adenoma, 12 patients one year after gastrectomy due to malignancy, and 20 healthy controls were analyzed by a leucocyte adherence inhibition RIA using /sup 51/Cr as well as corresponding and non-corresponding antigens. All adenomas were endoscopically and bioptically diagnosed small size tubular adenomas. Histologic grading of dysplasias was performed in accordance with Oehlert et al. (4) by multiple biopsy or by endoscopic polypectomia. Staging of the carcinomas in accordance with the UICC followed laparoscopical, intra-operative, and histological findings. Whereas precancerous and early stages demonstrated distinct sensibility against gastric carcinoma antigen late stages reacted as healthy controls. Because of severe scattering and serious failure in single results this test can only be a diagnostic aid in early stages of gastric carcinoma.

  10. Study of test methods for radionuclide migration in aerated zone

    International Nuclear Information System (INIS)

    Li Shushen; Guo Zede; Wang Zhiming

    1993-01-01

    Aerated zone is an important natural barrier against transport of radionuclides released from disposal facilities of LLRW. This paper introduces study methods for radionuclide migration in aerated zone, including determination of water movement, laboratory simulation test, and field tracing test. For one purpose, results obtained with different methods are compared. These methods have been used in a five-year cooperative research project between CIRP and JAERI for an establishment of methodology for safety assessment on shallow land disposal of LLRW

  11. 99mTc-HMPAO-labelled leucocyte scintigraphy in the diagnosis of infection after total knee replacement arthroplasty

    International Nuclear Information System (INIS)

    Park, Dong Rib; Kim, Jae Seung; Ryu, Jin Sook; Moon, Dae Hyuk; Bin, Seong Il; Cho, Woo Shin; Lee, Hee Kyung

    1999-01-01

    This study was performed to evaluate the usefulness of 99m Tc-HMPAO-labelled leucocyte scintigraphy for diagnosing prosthetic infection after total knee replacement arthroplasty without the aid of following bone marrow scintigraphy. The study subjects were 25 prostheses of 17 patients (one man and 16 women, mean age: 65 years) who had total knee replacement arthroplasty. After injection of 99m Tc-HMPAO-labelled leucocyte, the whole body planar and knee SPECT images were obtained in all patients. The subjects were classified into three groups according to clinical suspicion of prosthetic infection: Group A (n=11) with high suspicion of infection; Group B (n=6) with equivocal suspicion of infection, and Group C (n=8) with asymptomatic contralateral prostheses. Final diagnosis of infection was based on surgical, histological and bacteriological data and clinical follow-up. Infection was confirmed in 13 prostheses (11 in Group A and 2 in Group B). All prostheses in Group A were true positive. There were two true positive, one false positive and three true negative in Group B, and six true negatives and two false positive in Group C. Overall sensitivity, specificity, and accuracy for diagnosis of the infected knee prosthesis were 100%, 75% and 88%, respectively. 99m Tc-HMPAO-labelled leucocyte scintigraphy is a sensitive method for the diagnosis of infected knee prosthesis. However, false positive uptakes even in asymptomatic prosthesis suggest that bone marrow scintigraphy may be needed to achieve improved specificity

  12. X-ray-induced chromosome aberrations in the leucocytes of mouse and man

    International Nuclear Information System (INIS)

    Preston, R.J.; Brewen, J.G.

    1978-01-01

    In earlier studies it was shown that the frequency of dicentrics induced by X-rays in human leucocytes was about twice that induced in mouse leucocytes. The frequencies of deletions were similar in both species. However, the mouse cultures were fixed at 60 h and the human cultures at 54 h. In both cases it was likely that some of the cells analysed were in their second post-treatment mitosis. Further studies were carried out using fixation times of 48 h for both mouse and human cultures (three different human donors were used). The same relationships held here, namely twice as many dicentrics in humans, and similar deletion frequencies in both. The aberration frequencies observed were corrected to take account of second-diversion cells by assuming that cells containing a dicentric without an accompanying fragment were in their second division. There were more such cells in mouse than in human cultures. Further to increase reliance on the conclusions, cultures were fixed at the earliest times that 300 cells per dose could be obtained - 36 h for the mouse, 42 h for the human. The frequencies of dicentrics were increased in both, and a relationship of about 2:1 for human to mouse was obtained. Deletion frequencies were similar in both. Since no dicentrics without fragments were obtained, it appeared that aberration frequencies in first-division cells only were being compared. (author)

  13. Clinical experience with sup(99m)Tc-hexamethylpropylene-amineoxime for labelling leucocytes and imaging inflammation

    Energy Technology Data Exchange (ETDEWEB)

    Peters, A.M.; Danpure, H.J.; Osman, S.; Hawker, R.J.; Henderson, B.L.; Hodgson, H.J.; Kelly, J.D.; Neirinckx, R.D.; Lavender, J.P.

    1986-10-25

    Hexamethylpropylene-amineoxime (HMPAO) forms a lipid-soluble neutral complex with sup(99m)Tc which is rapidly incorporated into leucocytes in vitro. In six patients with suspected or known inflammatory disease, a 'mixed' leucocyte suspension isolated from 85 ml blood anticoagulated with acid-citrate-dextrose was labelled by sup(99m)Tc-HMPAO with a mean efficiency of 47% (SE2%), of which 78% (3) was taken up by granulocytes. Activity eluted more rapidly from other cell types in vitro than from granulocytes, which remained firmly labelled. Mean initial biodistribution of the label and granulocyte recovery in blood of 32% (8) at 30-40 min showed that the granulocytes were not significantly activated during labelling. All six patients were positive for inflammatory disease, as early as 30 min in five patients and at 3 h in the sixth; they all remained positive at 20-24 h. Four patients also received /sup 111/In-labelled 'pure' granulocytes. In terms of detail, the sup(99m)Tc images were comparable or superior to the /sup 111/In images.

  14. In vitro phagocytosis of methicillin resistant and methicillin sensitive staphylococcus aureus by human polymorphonuclear leucocytes

    International Nuclear Information System (INIS)

    Javed, N.; Tahir, R.; Abbas, A.

    2009-01-01

    Staphylococcus aureus is a gram positive bacterium that causes a number of diseases such as abscesses, infective endocarditis, septic arthritis, etc. It is acquiring resistance against many antibiotics like methicillin; therefore its control is becoming increasingly difficult. Peripheral blood phagocytes particularly polymorphonuclear leucocytes play an important role in the protective mechanisms against these organisms. Phagocytes interact with bacteria and phagocytose these microorganisms to kill them. Phenotypically different isolates of Staphylococcus aureus including methicillin resistant Staphylococcus aureus (MRSA) and methicillin sensitive Staphylococcus aureus (MSSA) were collected from various hospitals of Lahore, Pakistan. Fresh polymorphonuclaer leucocytes were obtained from healthy individuals by centrifugation using Ficol-Hypaque gradient combined with dextran sedimentation. Microbiological method was used for the determination of phagocytic index of phenotypic variants of Staphylococcus aureus. A significant difference was observed between the phagocytic index of both bacterial groups. MSSA group showed the Mean+-SD of 79.46%+-3.9 while MRSA group showed 72.35%+-2.5. Significant difference in phagocytic index indicates that it can be one of the mechanisms of MRSA to evade host immune system as compare to MSSA. (author)

  15. Brine migration test report: Asse Salt Mine, Federal Republic of Germany: Technical report

    International Nuclear Information System (INIS)

    Coyle, A.J.; Eckert, J.; Kalia, H.

    1987-01-01

    This report presents a summary of Brine Migration Tests which were undertaken at the Asse mine of the Federal Republic of Germany (FRG) under a bilateral US/FRG agreement. This experiment simulates a nuclear waste repository at the 800-m (2624-ft) level of the Asse salt mine in the Federal Republic of Germany. This report describes the Asse salt mine, the test equipment, and the pretest properties of the salt in the mine and in the vicinity of the test area. Also included are selected test data (for the first 28 months of operation) on the following: brine migration rates, thermomechaical behavior of the salt (including room closure, stress reading, and thermal profiles), borehole gas pressures, and borehole gas analyses. In addition to field data, laboratory analyses of pretest salt properties are included in this report. The operational phase of these experiments was completed on October 4, 1985, with the commencement of cooldown and the start of posttest activities. 7 refs., 68 figs., 48 tabs

  16. The Potent Humanin Analogue (HNG) Protects Germ Cells and Leucocytes While Enhancing Chemotherapy-Induced Suppression of Cancer Metastases in Male Mice.

    Science.gov (United States)

    Lue, YanHe; Swerdloff, Ronald; Wan, Junxiang; Xiao, Jialin; French, Samuel; Atienza, Vince; Canela, Victor; Bruhn, Kevin W; Stone, Brian; Jia, Yue; Cohen, Pinchas; Wang, Christina

    2015-12-01

    Humanin is a peptide that is cytoprotective against stresses in many cell types. We investigated whether a potent humanin analogue S14G-humanin (HNG) would protect against chemotherapy-induced damage to normal cells without interfering with the chemotherapy-induced suppression of cancer cells. Young adult male mice were inoculated iv with murine melanoma cells. After 1 week, cancer-bearing mice were randomized to receive either: no treatment, daily ip injection of HNG, a single ip injection of cyclophosphamide (CP), or CP+HNG and killed at the end of 3 weeks. HNG rescued the CP-induced suppression of leucocytes and protected germ cell from CP-induced apoptosis. Lung metastases were suppressed by HNG or CP alone, and further suppressed by CP+HNG treatment. Plasma IGF-1 levels were suppressed by HNG with or without CP treatment. To investigate whether HNG maintains its protective effects on spermatogonial stem cells, sperm output, and peripheral leucocytes after repeated doses of CP, normal adult male mice received: no treatment, daily sc injection of HNG, 6 ip injections of CP at 5-day intervals, and the same regimens of CP+HNG and killed at the end of 4 weeks of treatment. Cauda epididymal sperm counts were elevated by HNG and suppressed by CP. HNG rescued the CP-induced suppression of spermatogonial stem cells, sperm count and peripheral leucocytes. We conclude that HNG 1) protects CP-induced loss of male germ cells and leucocytes, 2) enhances CP-induced suppression of cancer metastases, and 3) acts as a caloric-restriction mimetic by suppressing IGF-1 levels. Our findings suggest that humanin analogues may be promising adjuvants to chemotherapy.

  17. {sup 99m}Tc-HMPAO-labelled leucocyte scintigraphy in the diagnosis of infection after total knee replacement arthroplasty

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dong Rib [College of Medicine, Kunkuk Univ., Seoul (Korea, Republic of); Kim, Jae Seung; Ryu, Jin Sook; Moon, Dae Hyuk; Bin, Seong Il; Cho, Woo Shin; Lee, Hee Kyung [College of Medicine, Ulsan Univ., Seoul (Korea, Republic of)

    1999-08-01

    This study was performed to evaluate the usefulness of {sup 99m}Tc-HMPAO-labelled leucocyte scintigraphy for diagnosing prosthetic infection after total knee replacement arthroplasty without the aid of following bone marrow scintigraphy. The study subjects were 25 prostheses of 17 patients (one man and 16 women, mean age: 65 years) who had total knee replacement arthroplasty. After injection of {sup 99m}Tc-HMPAO-labelled leucocyte, the whole body planar and knee SPECT images were obtained in all patients. The subjects were classified into three groups according to clinical suspicion of prosthetic infection: Group A (n=11) with high suspicion of infection; Group B (n=6) with equivocal suspicion of infection, and Group C (n=8) with asymptomatic contralateral prostheses. Final diagnosis of infection was based on surgical, histological and bacteriological data and clinical follow-up. Infection was confirmed in 13 prostheses (11 in Group A and 2 in Group B). All prostheses in Group A were true positive. There were two true positive, one false positive and three true negative in Group B, and six true negatives and two false positive in Group C. Overall sensitivity, specificity, and accuracy for diagnosis of the infected knee prosthesis were 100%, 75% and 88%, respectively. {sup 99m}Tc-HMPAO-labelled leucocyte scintigraphy is a sensitive method for the diagnosis of infected knee prosthesis. However, false positive uptakes even in asymptomatic prosthesis suggest that bone marrow scintigraphy may be needed to achieve improved specificity.

  18. The field migration tests of 237Np, 238Pu, 241Am and 90Sr in aerated loess, aquifer and engineering barrier materials

    International Nuclear Information System (INIS)

    Li Shushen; Wang Zhiming; Zhao Yingjie; Fan Zhiwen; Liu Chunli; An Yongfeng; Yang Yue'e; Wu Qinghua

    2003-01-01

    This paper introduces the field migration tests of 237 Np, 238 Pu, 241 Am and 90 Sr in aerated loess, aquifer and engineering barrier materials. The tests in the aerated loess and engineering barrier materials were carried out under both natural and artificial sprinkling (15 mm/d) conditions. The tests in aquifer were carried out in both assemblies packed with undisturbed aquifer media and a definite undisturbed area. The results indicate that after 3 years tests no significant migrations were seen for all nuclides in engineering barrier materials under two kinds of conditions and in aerated loess under natural conditions. For the aerated loess under artificial sprinkling conditions, 2.7 cm (center of mass) migration in the area directly below the sand tracer layer (named as area 1) and 13 cm (peak) migration in the area outside the area 1 for 90 Sr were observed; There was no migration for 237 Np, 238 Pu and 241 Am. It was discovered that the sand layer used as carrier of nuclide tracer has barrier effect on unsaturated water and an influence on nuclide migration. This has been demonstrated by the inter comparison experiment with both sand and loess as tracer carrier. In the tracer tests of undisturbed aquifer area there was no significant migration of 237 Np, 238 Pu, 241 Am and 90 Sr after 1023 days. In the assembly 8 there was no significant migration for 238 Pu and 241 Am and a small backward migration 0.95 cm for 237 Np and 4.7 cm migration (center of mass) for 90 Sr were observed. The tests also indicate that there is no significant difference of nuclide migration in ordinary and degraded cement

  19. Up-regulation of leucocytes genes implicated in telomere dysfunction and cellular senescence correlates with depression and anxiety severity scores.

    Directory of Open Access Journals (Sweden)

    Jean-Raymond Teyssier

    Full Text Available BACKGROUND: Major depressive disorder (MDD is frequently associated with chronic medical illness responsible of increased disability and mortality. Inflammation and oxidative stress are considered to be the major mediators of the allostatic load, and has been shown to correlate with telomere erosion in the leucocytes of MDD patients, leading to the model of accelerated aging. However, the significance of telomere length as an exclusive biomarker of aging has been questioned on both methodological and biological grounds. Furthermore, telomeres significantly shorten only in patients with long lasting MDD. Sensitive and dynamic functional biomarkers of aging would be clinically useful to evaluate the somatic impact of MDD. METHODOLOGY: To address this issue we have measured in the blood leucocytes of MDD patients (N=17 and controls (N=16 the expression of two genes identified as robust biomarkers of human aging and telomere dysfunction: p16(INK4a and STMN1. We have also quantified the transcripts of genes involved in the repair of oxidative DNA damage at telomeres (OGG1, telomere regulation and elongation (TERT, and in the response to biopsychological stress (FOS and DUSP1. RESULTS: The OGG1, p16(INK4a, and STMN1 gene were significantly up-regulated (25 to 100% in the leucocytes of MDD patients. Expression of p16(INK4a and STMN1 was directly correlated with anxiety scores in the depression group, and that of p16(INK4a, STMN and TERT with the depression and anxiety scores in the combined sample (MDD plus controls. Furthermore, we identified a unique correlative pattern of gene expression in the leucocytes of MDD subjects. CONCLUSIONS: Expression of p16(INK4 and STMN1 is a promising biomarker for future epidemiological assessment of the somatic impact of depressive and anxious symptoms, at both clinical and subclinical level in both depressive patients and general population.

  20. Abdominal scintigraphy using 99mTc-HMPAO-labelled leucocytes in patients with seronegative spondylarthropathies without clinical evidence of inflammatory bowel disease

    International Nuclear Information System (INIS)

    Alonso, J.C.; Lopez-Longo, F.J.; Lampreave, J.L.; Gonzalez, C.M.; Vegazo, O.; Carreno, L.; Almoguera, I.

    1996-01-01

    Abdominal scintigraphy with technetium-99m hexamethylpropylene amine oxime ( 99m Tc-HMPAO)-labelled leucocytes is an excellent tool for evaluating disease extent and activity of intestinal lesions in patients with inflammatory bowel disease (IBD). In some cases of seronegative spondylarthropathies (SSp), IBD may remain subclinical. The aim of this study was to evaluate the presence of positive abdominal scintigraphy in patients with SSp and without clinical symptoms or signs of IBD. To this end we studied 32 patients with active SSp (European Spondylarthropathy Study Group 1991 criteria) without clinical evidence of IBD (eight had ankylosing spondylitis, four psoriatic arthritis, three reactive arthritis an 17 undifferentiated SSp) and 11 controls without SSp. All SSp and control patients received similar doses of non-steroidal anti-inflammatory drugs (NSAIDs). Abdominal scintigraphic images were obtained at 30 and 120 min after re-injection of 99m Tc-HMPAO-labelled leucocytes. The 99m Tc-HMPAO-labelled leucocyte scan was positive in 17 patients with SSp (53.1%) (six with ankylosing spondylitis, three with psoriatic arthritis, two with reactive arthritis and six with undifferentiated SSp). Fourteen patients scored from 2 to 4 on the intensity of uptake scale. The colon and terminal ileum were predominantly involved. Axial involvement was more frequent in patients with a positive scan than in patients with negative results (P 99m Tc-HMPAO-labelled leucocyte scan shows increased uptake among patients with SSp without evidence of IBD. These findings provide new evidence linking SSp with intestinal inflammation and suggest that in some cases a bowel-related process could contribute to the development of SSp. Long-term follow-up studies with more patients are necessary to evaluate the diagnostic and therapeutic implications of these results. (orig.). With 3 figs., 3 tabs

  1. Long-term chloride migration coefficient in slag cement-based concrete and resistivity as an alternative test method

    NARCIS (Netherlands)

    van Noort, R.; Hunger, M.; Spiesz, P.R.

    2016-01-01

    This article reports on investigations of the resistivity and chloride migration coefficient (DRCM) obtained in the accelerated Rapid Chloride Migration test for slag cement-based concretes. Determinations of the resistivity and DRCM were performed on 47 different concrete compositions, up to the

  2. Comparison of indium-111-oxine and indium-111-acetylacetone labelled leucocytes in the diagnosis of inflammatory disease

    Energy Technology Data Exchange (ETDEWEB)

    Peters, A.M.; Karimjee, S.; Saverymuttu, S.H.; Lavender, J.P. (Hammersmith Hospital, London (UK))

    1982-11-01

    /sup 111/In leucocyte scanning in a series of 132 patients has shown this technique to be a reliable and accurate means of diagnosing sepsis. Labelling with /sup 111/In oxine and with /sup 111/In acetylacetone gave similar values of sensitivity and specificity, and higher than those of ultrasound.

  3. Sodium content and sodium efflux of mononuclear leucocytes from young subjects at increased risk of developing essential hypertension

    DEFF Research Database (Denmark)

    Pedersen, K E; Nielsen, J R; Klitgaard, N A

    1990-01-01

    Mononuclear leucocytes were used as a cellular model for the in vitro measurements of volume, sodium and potassium content, sodium efflux rate constants and absolute sodium efflux in order to assess any cellular changes in young men at increased risk of developing essential hypertension...

  4. Influences of environmental cues, migration history and habitat familiarity on partial migration

    DEFF Research Database (Denmark)

    Skov, Christian; Aarestrup, Kim; Baktoft, Henrik

    2010-01-01

    The factors that drive partial migration in organisms are not fully understood. Roach (Rutilus rutilus), a freshwater fish, engage in partial migration where parts of populations switch between summer habitats in lakes and winter habitats in connected streams. To test if the partial migration trait...

  5. Phenotypic differences in leucocyte populations among healthy preterm and full-term newborns.

    Science.gov (United States)

    Quinello, C; Silveira-Lessa, A L; Ceccon, M E J R; Cianciarullo, M A; Carneiro-Sampaio, M; Palmeira, P

    2014-07-01

    The immune system of neonates has been considered functionally immature, and due to their high susceptibility to infections, the aim of this study was to analyse the phenotypic differences in leucocyte populations in healthy preterm and full-term newborns. We evaluated the absolute numbers and frequencies of dendritic cells (DCs) and DC subsets, monocytes and T and B lymphocytes and subsets in the cord blood of healthy moderate and very preterm (Group 1), late preterm (Group 2) and full-term (Group 3) newborns and in healthy adults, as controls, by flow cytometry. The analyses revealed statistically higher absolute cell numbers in neonates compared with adults due to the characteristic leucocytosis of neonates. We observed a lower frequency of CD80(+) myeloid and plasmacytoid DCs in Group 1 and reduced expression of TLR-4 on myeloid DCs in all neonates compared with adults. TLR-2(+) monocytes were reduced in Group 1 compared with Groups 2 and 3, and TLR-4(+) monocytes were reduced in Groups 1 and 2 compared with Group 3. The frequencies and numbers of naïve CD4(+) T and CD19(+) B cells were higher in the three groups of neonates compared with adults, while CD4(+) effector and effector memory T cells and CD19(+) memory B cells were elevated in adults compared with neonates, as expected. Our study provides reference values for leucocytes in cord blood from term and preterm newborns, which may facilitate the identification of immunological deficiencies in protection against extracellular pathogens. © 2014 John Wiley & Sons Ltd.

  6. HIV Prevention among Mexican Migrants at Different Migration Phases: Exposure to Prevention Messages and Association With Testing Behaviors

    Science.gov (United States)

    Martinez-Donate, Ana P.; Rangel, M. Gudelia; Zhang, Xiao; Simon, Norma-Jean; Rhoads, Natalie; Gonzalez-Fagoaga, J. Eduardo; Gonzalez, Ahmed Asadi

    2016-01-01

    Mobile populations are at increased risk for HIV infection. Exposure to HIV prevention messages at all phases of the migration process may help decrease im/migrants’ HIV risk. We investigated levels of exposure to HIV prevention messages, factors associated with message exposure, and the association between exposure to prevention messages and HIV testing behavior among Mexican im/migrants at different phases of the migration process. We conducted a cross-sectional, probability survey of Mexican im/migrants (N=3,149) traveling through the border city of Tijuana, Mexico. The results indicate limited exposure to prevention messages (57%–75%) and suboptimal last 12-month HIV testing rates (14%–25%) across five migration phases. Compared to pre-departure levels (75%), exposure to messages decreases at all post-departure migration phases (57%–63%, pmigration continuum. PMID:26595267

  7. Prevalence of positive urinary dipstick analysis (leucocyte esterase, nitrite, haemoglobin, or glucose) in a population of 3645 adult subjects--consequence for measurement of urinary albumin excretion rate

    DEFF Research Database (Denmark)

    Clausen, P; Jensen, J S; Borch-Johnsen, K

    1998-01-01

    OBJECTIVES: To assess prevalence of positive urinary dipstick analysis for leucocyte esterase, nitrite, haemoglobin, or glucose in the general population and measure the urinary albumin excretion rate (UAER) in subjects with or without a positive dipstick analysis. DESIGN: A cross-sectional study...... of 3645 subjects. SETTING: An unselected urban population study. MAIN OUTCOME MEASURES: Prevalence data of positive dipstick analyses and UAER values. RESULTS: Prevalence data of a positive dipstick analysis were 12%, 4%, 3% and 6%, respectively, for leucocyte esterase, nitrite, haemoglobin, and glucose...

  8. Clinical significance of abdominal scintigraphy using {sup 99m}Tc-HMPAO-labelled leucocytes in patients with seronegative spondyloarthropathies

    Energy Technology Data Exchange (ETDEWEB)

    Alonso Farto, J.C.; Almoguera Arias, I.; Ortega Valle, A.; Perez Vazquez, J.M. [Department of Nuclear Medicine, Univ. Complutense, Madrid (Spain); Lopez Longo, F.J.; Gonzalez Fernandez, C.M.; Monteagudo Saez, I.; Bascones, M.; Carreno Perez, L. [Department of Rheumatology, ' ' Hospital Universitario Gregorio Maranon' ' , Universidad Complutense, Madrid (Spain)

    2000-12-01

    Abdominal scintigraphy shows silent gut inflammation in patients with spondyloarthropathies (Sp) without clinical evidence of gut inflammation. Abdominal scintigraphy images are different than those obtained in patients with ulcerative colitis or Crohn's disease and are not related to the anti-inflammatory drugs administered. The aim of this study was to examine the clinical associations of findings on abdominal scintigraphy in patients with Sp. A total of 204 Sp patients (European Spondylarthropathy Study Group 1991 criteria) and 54 non-Sp controls receiving non-steroidal anti-inflammatory drugs were studied. Abdominal scintigraphy images were obtained at 30 and 120 min after injection of technetium-99m hexamethylpropylene amine oxime ({sup 99m}Tc-HMPAO)-labelled leucocytes. {sup 99m}Tc-HMPAO-labelled leucocyte scans were positive in 104 Sp patients (50.9%) and in six non-Sp controls (2.9%) (P<0.001; OR=8.32; 95% CI=3.23-22.67). Silent gut inflammation was not associated with any of the following: age of onset, duration of evolution, sex, family history of Sp or psoriasis, articular manifestations, extra-articular manifestations, radiological findings or HLA-B27 positivity. Positive abdominal scintigraphy was associated with active disease (P<0.0001; OR=52.7; 95% CI=19-145.6) and an increase in the C-reactive protein (P<0.005; OR=3.4; 95% CI=1.5-7.4). It is concluded that (a) abdominal scintigraphy using {sup 99m}Tc-HMPAO-labelled leucocytes is of value in detecting the silent gut inflammation in Sp patients, and (b) silent gut inflammation is related to the clinical activity, but is not associated with any particular type of illness or with HLA-B27. (orig.)

  9. Contribution of technetium-99m hexamethylpropylene amine oxime labelled leucocyte scintigraphy to the diagnosis of diabetic foot infection

    International Nuclear Information System (INIS)

    Devillers, A.; Moisan, A.; Garin, E.; Bourguet, P.; Hennion, F.; Poirier, J.Y.

    1998-01-01

    We conducted a prospective study in order to evaluate the contribution of technetium-99m hexamethylpropylene amine oxime (HMPAO) labelled leucocyte scintigraphy to the diagnosis and follow-up of osteomyelitis in the diabetic foot. The study was conducted between October 1992 and November 1996 and included 42 patients (30 men and 12 women; mean age 63 years) with diabetes mellitus (type 1, n = 22, type 2, n = 20) who had a total of 56 diabetic foot ulcers. The initial exploration included standard radiography, three-phase bone scintigraphy and 99m Tc-HMPAO labelled leucocyte scintigraphy (HMPAO-LS), performed within a 3-day interval. For the 56 ulceration sites, 26 cases of osteomyelitis were diagnosed: ten on the basis of radiographic and histological/bacteriological criteria after bone biopsy, 11 after radiographic follow-up and five on the basis of biopsy results alone. No osteomyelitis was present at 30 sites, there were seven cases of cellulitis. The sensitivity and specificity of 99m Tc-HMPAO-LS were 88.4% and 96.6% respectively (23 true-positives, 29 true-negatives, one false-positive, three false-negatives). The accuracy of radiography, 99m Tc-methylene diphosphonate and HMPAO-LS was 69.6%, 62.5%, and 92.9%, respectively. Follow-up scintigraphy (n = 14) 4 months after initial diagnosis and 1 month after antibiotic withdrawal confirmed cure of osteomyelitis despite the absence of complete clinical regression of the ulcers. In conclusion, 99m Tc-HMPAO labelled leucocyte scintigraphy was found to be an excellent method for the diagnosis of osteomyelitis in the diabetic foot. It can contribute to follow-up, particularly when clinical regression of perforating ulcers is incomplete and cure of osteomyelitis must be confirmed in order that antibiotic treatment may be discontinued. (orig.)

  10. Contribution of technetium-99m hexamethylpropylene amine oxime labelled leucocyte scintigraphy to the diagnosis of diabetic foot infection

    Energy Technology Data Exchange (ETDEWEB)

    Devillers, A.; Moisan, A.; Garin, E.; Bourguet, P. [CRLCC Eugene Marquis, Service de Medecine Nucleaire, Rennes (France); Hennion, F.; Poirier, J.Y. [CHRU Pontchaillou, Service d`Endocrinologie, Rennes (France)

    1998-02-01

    We conducted a prospective study in order to evaluate the contribution of technetium-99m hexamethylpropylene amine oxime (HMPAO) labelled leucocyte scintigraphy to the diagnosis and follow-up of osteomyelitis in the diabetic foot. The study was conducted between October 1992 and November 1996 and included 42 patients (30 men and 12 women; mean age 63 years) with diabetes mellitus (type 1, n = 22, type 2, n = 20) who had a total of 56 diabetic foot ulcers. The initial exploration included standard radiography, three-phase bone scintigraphy and {sup 99m}Tc-HMPAO labelled leucocyte scintigraphy (HMPAO-LS), performed within a 3-day interval. For the 56 ulceration sites, 26 cases of osteomyelitis were diagnosed: ten on the basis of radiographic and histological/bacteriological criteria after bone biopsy, 11 after radiographic follow-up and five on the basis of biopsy results alone. No osteomyelitis was present at 30 sites, there were seven cases of cellulitis. The sensitivity and specificity of {sup 99m}Tc-HMPAO-LS were 88.4% and 96.6% respectively (23 true-positives, 29 true-negatives, one false-positive, three false-negatives). The accuracy of radiography, {sup 99m}Tc-methylene diphosphonate and HMPAO-LS was 69.6%, 62.5%, and 92.9%, respectively. Follow-up scintigraphy (n = 14) 4 months after initial diagnosis and 1 month after antibiotic withdrawal confirmed cure of osteomyelitis despite the absence of complete clinical regression of the ulcers. In conclusion, {sup 99m}Tc-HMPAO labelled leucocyte scintigraphy was found to be an excellent method for the diagnosis of osteomyelitis in the diabetic foot. It can contribute to follow-up, particularly when clinical regression of perforating ulcers is incomplete and cure of osteomyelitis must be confirmed in order that antibiotic treatment may be discontinued. (orig.) With 5 figs., 3 tabs., 28 refs.

  11. Interactions of opsonized immune complexes with whole blood cells: binding to erythrocytes restricts complex uptake by leucocyte populations

    DEFF Research Database (Denmark)

    Nielsen, C H; Svehag, S E; Marquart, H V

    1994-01-01

    binding, the main contributors being B cells. E initially inhibited and then later enhanced the IC binding to lymphocytes, suggesting that E promote B cell uptake of C3d,g-covered IC via CR2. Our findings, that E can restrict the IC uptake by circulating leucocytes, and that an IC-induced degranulation...

  12. Nuclides migration tests under deep geological conditions

    International Nuclear Information System (INIS)

    Kumata, M.; Vandergraaf, T.T.

    1991-01-01

    Migration behaviour of technetium and iodine under deep geological conditions was investigated by performing column tests under in-situ conditions at the 240 m level of the Underground Research Laboratory (URL) constructed in a granitic batholith near Pinawa, Manitoba, Canada. 131 I was injected with tritiated water into the column. Tritium and 131 I were eluted simultaneously. Almost 100 % of injected 131 I was recovered in the tritium breakthrough region, indicating that iodine moved through the column almost without retardation under experimental conditions. On the other hand, the injected technetium with tritium was strongly retarded in the column even though the groundwater was mildly reducing. Only about 7 % of injected 95m Tc was recovered in the tritium breakthrough region and the remaining fraction was strongly sorbed on the dark mafic minerals of column materials. This strong sorption of technetium on the column materials had not been expected from the results obtained from batch experiments carried out under anaerobic conditions. (author)

  13. Laboratory investigations in support of the migration experiments at the Grimsel test site

    International Nuclear Information System (INIS)

    Bradbury, M.H.

    1989-04-01

    Tracer migration experiments are in progress at the underground Grimsel Test Site (GTS). In order to interpret tracer tests a supporting laboratory experimental programme is essential. This report describes the results from the first part of such a programme. Insufficient material from the protomylonite surrounding the fracture was available from the migration site for the foreseen experiments and so mylonite from an adjacent fault zone was used instead. Detailed petrographic and mineralogical characterisations of the protomylonite and mylonite were carried out. The mylonitic samples from these two sources were shown to be mineralogically similar although some potentially significant differences did exist. The promylonite was slightly depleted in those minerals (chlorite, muscovite etc.) which could be significant for sorption/exchange processes. This may have consequences for predictions of the sorption behaviour in the migration zone deduced from laboratory measurements. The fracture zone exhibited groundwater discharge at five discrete channels situated in a single fracture. Groundwater emerging from these five locations, and from two boreholes intersecting the plane of the fracture, were sampled and analysed at approximately monthly intervals over a period of 12 months. The results showed that there were no significant temporal or spatial variations in the compositions. This groundwater may be characterised as being of low ionic strength (∼9.6) with Na + , Ca 2+ , Cl - , SO 4 2- , F - and HCO 3 - as the major ions. The partial pressure of CO 2 calculated to be in equilibrium with the groundwater was ∼4x10 -6 bar. (author) 14 figs., 17 tabs., 31 refs

  14. Testing the spatial neutrality of the REMI net migration equation

    International Nuclear Information System (INIS)

    Barr, C.F.; Perrigo, T.A.; Daneshvary, N.; Rickman, D.S.

    1994-01-01

    The U.S. Department of Energy (DOE), Yucca Mountain Site Characterization Project Office (YMPO) is conducting socioeconomic studies in the State of Nevada in accordance with the Nuclear Waste Policy Act of 1982, as amended. The main purpose of the socioeconomic program is to avoid or minimize adverse socioeconomic impacts of the Yucca Mountain Site Characterization Project (YMP) on local communities, counties, and the state of Nevada. This objective is being met by collecting data that can be used by the DOE and affected units of local government to monitor economic and demographic variables and forecast changes that may occur as a direct result of the YMP. One of the tools being used to develop population and employment forecasts in Clark, Lincoln, and Nye counties in Nevada is Regional Economic Modeling Inc.'s (REMI) Economic-Demographic Forecasting and Simulation (EDFS) model. The REMI model is widely used in applied economics for: forecasting and planning; economic development; transportation; energy and natural resources; taxation, budget, and welfare; United States policies; and environmental policies. This model was chosen by the DOE because it is a dynamic econometric model based on accepted economic theory and principles, and because of its favorable rating compared to other available models. The dynamic nature of the model offers improvements in forecasting capabilities over input-output models. Because the DOE is making extensive use of the REMI model, it is necessary to evaluate the model's forecasting performance. This study is an empirical test of the restrictions in the REMI model's net migration equation. The REMI model pools the data across regions to estimate net migration into each region. For this study we will examine Clark County net migration. We hypothesize that due to the differences among regions (such as distance, and geographic and cultural features specific to each region), pooling the data across regions may not be appropriate

  15. Development of lyophilized kit of Tin-Glucoheptonate for in vitro labeling of leucocytes with {sup 99m}Tc; Desenvolvimento de reagente liofilizado de glucoheptonato-estanho para marcacao de leucocitos com Tecnecio-99m in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Rosemeire Fagundes

    2007-07-01

    The study and localization of inflammatory and infection process in Nuclear Medicine represents a relevant tool in diagnostic procedures. In same cases, the diagnostic is easy and based on anamnesis and clinical observation; in other cases, the patients are asymptomatic or present non specific symptoms that difficult the diagnostic. The early diagnostic of inflammatory or infectious process allow the early introduction of therapy and prevents complications. Farther, the differentiation between inflammation and infection is of extreme importance as well as the localization of the focus. The use of labeled leucocytes, studied and applied in much pathologies, is the method of choice for the visualization of inflammation and infection. The scintigraphy using labeled leucocytes was introduced at 1976 by McAffe and Thakur and since of this is used in the diagnostic of different pathologies related to leucocyte infiltration like intestinal inflammatory disease, bone or prosthetic-vascular infections. The in vitro labeling of leucocytes with {sup 111}In was performed using oxime or tropolone as ligand and with {sup 99m}Tc using hexamethylpropylene amine oxime (HMPAO) as ligand, resulting in a lipophilic complex. The {sup 99m}Tc-HMPAG complex was preferably employed in many indications and countries do to the ideal physical properties of {sup 99m}Tc that results in low dose to the patient. However, the labeling employing the HMPAO complex results in some disadvantages like the low stability of the complex, and some requirements related to the {sup 99m}Tc elution (like the time pos elution), beyond the high cost of the compound that is imported. The aim of this work was the development of a tin-glucoheptonate lyophilized kit for in vitro leucocytes labeling with {sup 99m}Tc using the pre-stannization method. The optimization of the labeling technique was developed using leucocytes isolated from total blood and employing different volumes of the tinglucoheptonate reagent and

  16. Preparation of tracing source layer in simulation test of nuclide migration

    International Nuclear Information System (INIS)

    Zhao Yingjie; Ni Shiwei; Li Weijuan; Yamamoto, T.; Tanaka, T.; Komiya, T.

    1993-01-01

    In cooperative research between CIRP and JAERI on safety assessment for shallow land disposal of low level radioactive waste, a laboratory simulation test of nuclide migration was carried out, in which the undisturbed loess soil column sampled from CIRP' s field test site was used as testing material, three nuclides, Sr-85, Cs-137 and Co-60 were used as tracers. Special experiment on tracing method was carried out, which included measuring pH value of quartz sand in HCl solution, determining the eligible water content of quartz sand as tracer carrier, measuring distribution uniformity of nuclides in the tracing quartz sand, determining elution rate of nuclides from the tracing quartz sand and detecting activity uniformity of tracing source layer. The experiment results showed that the tracing source layer, in which fine quartz sand was used as tracer carrier, satisfied expected requirement. (1 fig.)

  17. In vitro effects of Italian Lavandula multifida L. leaf extracts on gilthead seabream (Sparus aurata) leucocytes and SAF-1 cells.

    Science.gov (United States)

    Fazio, Angela; Cerezuela, Rebeca; Panuccio, Maria Rosaria; Cuesta, Alberto; Esteban, Maria Ángeles

    2017-07-01

    Lavandula multifida is very appreciated by pharmaceutical and cosmetic industries. In Italy is only found in Calabria and Sicily and, at present, urge its valorization due to its high extinction and genetic erosion risks. Possible applications of L. multifida extracts as immunostimulant in fish aquaculture were assayed by using gilthead seabream (Sparus aurata) as a marine fish model, due to its importance in fish aquaculture. The in vitro effects of both aqueous and ethanolic leaf extracts obtained from two Italian populations of L. multifida on head kidney leucocyte activities (viability, phagocytosis, respiratory burst and peroxidase content) were assessed. Furthermore, the possible cytotoxic effects of the extracts on SAF-1 cells and their bactericidal effects on three fish pathogenic bacteria (Vibrio harveyi, Vibrio anguillarum, Aeromonas salmonicida) were also evaluated. All the assays were performed in comparison with leaf extracts obtained from a widely-distributed species as L. angustifolia. Results showed that water and ethanolic leaf extracts obtained from L. multifida enhanced innate immune activities of S. aurata HK leucocytes. Furthermore, SAF-1 cell viability was not affected significantly after being incubated with the extracts. These extracts did not exert any bactericidal activity on the pathogenic bacterial strains tested in the present study. Results obtained in the present work suggested the possibility of use such extracts in in vivo studies in order to corroborate the possibility of their use in aquaculture. Their use could prevent to improve fish defense against pathogenic infections through enhancement of the fish immune status. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Grimsel Test Site: modelling radionuclide migration field experiments

    International Nuclear Information System (INIS)

    Heer, W.; Hadermann, J.

    1994-09-01

    In the migration field experiments at Nagra's Grimsel Test Site, the processes of nuclide transport through a well defined fractured shear-zone in crystalline rock are being investigated. For these experiments, model calculations have been performed to obtain indications on validity and limitation of the model applied and the data deduced under field conditions. The model consists of a hydrological part, where the dipole flow fields of the experiments are determined, and a nuclide transport part, where the flow field driven nuclide propagation through the shear-zone is calculated. In addition to the description of the model, analytical expressions are given to guide the interpretation of experimental results. From the analysis of experimental breakthrough curves for conservative uranine, weakly sorbing sodium and more stronger sorbing strontium tracers, the following main results can be derived: i) The model is able to represent the breakthrough curves of the migration field experiments to a high degree of accuracy, ii) The process of matrix diffusion is manifest through the tails of the breakthrough curves decreasing with time as t -3/2 and through the special shape of the tail ends, both confirmed by the experiments, iii) For nuclide sorbing rapidly, not too strongly, linearly, and exhibiting a reversible cation exchange process on fault gouge, the laboratory sorption coefficient can reasonably well be extrapolated to field conditions. Adequate care in selecting and preparing the rock samples is, of course, a necessary requirement. Using the parameters determined in the previous analysis, predictions are made for experiments in a smaller an faster flow field. For conservative uranine and weakly sorbing sodium, the agreement of predicted and measured breakthrough curves is good, for the more stronger sorbing strontium reasonable, confirming that the model describes the main nuclide transport processes adequately. (author) figs., tabs., 29 refs

  19. Release of leukotriene C4 from human polymorphonuclear leucocytes as determined by radioimmunoassay

    International Nuclear Information System (INIS)

    Aehringhaus, U.; Woelbling, R.H.; Peskar, B.M.; Peskar, B.A.; Koenig, W.; Patrono, C.

    1982-01-01

    Rabbits were immunized with a conjugate of leukotriene (LT)C 4 and bovine serum albumin prepared by coupling the single free amino group of the hapten to the protein using gluteraldehyde. Binding of [ 3 H]LTC 4 to the antibodies obtained is inhibited by 50% with 1.5 ng LTC 4 . The relative cross-section of LTD 4 is 16% and of LTC 4 -methyl ester 3.6%. The validity of the radioimmunoassay was demonstrated by comparison with bioassay using the isolated guinea pig ileum. Using the radioimmunoassay it could be shown that endogenous LTC 4 is released in a dose-dependent manner by human polymorphonuclear leucocytes stimulated with the divalent cation ionophore A23187. (Auth.)

  20. Individual versus Household Migration Decision Rules: Gender and Marital Status Differences in Intentions to Migrate in South Africa.

    Science.gov (United States)

    Gubhaju, Bina; De Jong, Gordon F

    2009-03-01

    This research tests the thesis that the neoclassical micro-economic and the new household economic theoretical assumptions on migration decision-making rules are segmented by gender, marital status, and time frame of intention to migrate. Comparative tests of both theories within the same study design are relatively rare. Utilizing data from the Causes of Migration in South Africa national migration survey, we analyze how individually held "own-future" versus alternative "household well-being" migration decision rules effect the intentions to migrate of male and female adults in South Africa. Results from the gender and marital status specific logistic regressions models show consistent support for the different gender-marital status decision rule thesis. Specifically, the "maximizing one's own future" neoclassical microeconomic theory proposition is more applicable for never married men and women, the "maximizing household income" proposition for married men with short-term migration intentions, and the "reduce household risk" proposition for longer time horizon migration intentions of married men and women. Results provide new evidence on the way household strategies and individual goals jointly affect intentions to move or stay.

  1. Radiolabelling of autologous leucocytes: technique and clinical application

    International Nuclear Information System (INIS)

    Strobl-Jaeger, E.; Kolbe, H.; Ludwig, H.; Sinzinger, H.

    1988-01-01

    Gamma-camera imaging after injection of radiolabelled autologous leucocytes can be very helpful in the diagnosis, localization and further clinical treatment of inflammatory diseases. We present a technique allowing sterile separation of white blood cells and labelling with 99m Tc-phytate or -oxine and with 111 In-oxine, -oxine sulphate or -tropolone. The method is non-invasive and the radiation dose amounts to less than 80 mrad using 100 μCi 111 Indium. The use of radiolabelled granulocytes is of particular diagnostic value in patients with septicaemia of unknown origin. Whole body scanning allows not only visualization of enhanced splenic uptake in septicaemia, but also localization of an inflammatory process. Preferential indications for a diagnostic approach using radiolabelled granulocytes are inflammatory abdominal processes which cannot easily be documented by means of other non-invasive techniques, such as inflammatory bowel disease (Crohn's diseases and ulcerative colitis), arthritic processes and abscesses of the liver and spleen, as well as subphrenic and retroperitoneal abscesses. Untreated osteomyelitis can be located with the help of labelled granulocytes, but in patients treated with antibiotics a false negative result is obtained in approximately 50 % of cases for as yet unknown reasons, even in the presence of a still active osteomyelitic process. (Authors)

  2. Leucocyte protein Trojan, a possible regulator of apoptosis.

    Science.gov (United States)

    Petrov, Petar; Syrjänen, Riikka; Uchida, Tatsuya; Vainio, Olli

    2017-02-01

    Trojan is a leucocyte-specific protein, cloned from chicken embryonic thymocyte cDNA library. The molecule is a type I transmembrane protein with an extracellular CCP domain, followed by two FN3 domains. Its cytoplasmic tail is predicted to possess a MAPK docking and a PKA phosphorylation sites. Trojan has been proposed to have an anti-apoptotic role based on its differential expression on developing thymocyte subpopulations. Using a chicken cell line, our in vitro studies showed that upon apoptosis induction, Trojan expression rises dramatically on the surface of surviving cells and gradually decreases towards its normal levels as cells recover. When sorted based on their expression levels of Trojan, cells with high expression appeared less susceptible to apoptotic induction than those bearing no or low levels of Trojan on their surface. The mechanism by which the molecule exerts its function is yet to be discovered. We found that cells overexpressing Trojan from a cDNA plasmid show elevated steady-state levels of intracellular calcium, suggesting the molecule is able to transmit cytoplasmic signals. The mechanistic nature of Trojan-induced signalling is a target of future investigation. In this article, we conducted a series of experiments that suggest Trojan as an anti-apoptotic regulator. © 2016 APMIS. Published by John Wiley & Sons Ltd.

  3. Testing the effects of the numerical implementation of water migration on models of subduction dynamics

    Science.gov (United States)

    Quinquis, M. E. T.; Buiter, S. J. H.

    2013-10-01

    Subduction of oceanic lithosphere brings water into Earth's upper mantle. Previous numerical studies have shown how slab dehydration and mantle hydration can impact the dynamics of a subduction system by allowing a more vigorous mantle flow and promoting localisation of deformation in lithosphere and mantle. The depths at which dehydration reactions occur in the hydrated portions of the slab are well constrained in these models by thermodynamic calculations. However, the mechanism by which free water migrates in the mantle is incompletely known. Therefore, models use different numerical schemes to model the migration of free water. We aim to show the influence of the numerical scheme of free water migration on the dynamics of the upper mantle and more specifically the mantle wedge. We investigate the following three migration schemes with a finite-element model: (1) element-wise vertical migration of free water, occurring independent of the material flow; (2) an imposed vertical free water velocity; and (3) a Darcy velocity, where the free water velocity is calculated as a function of the pressure gradient between water and the surrounding rocks. In addition, the material flow field also moves the free water in the imposed vertical velocity and Darcy schemes. We first test the influence of the water migration scheme using a simple Stokes flow model that simulates the sinking of a cold hydrated cylinder into a hot dry mantle. We find that the free water migration scheme has only a limited impact on the water distribution after 1 Myr in these models. We next investigate slab dehydration and mantle hydration with a thermomechanical subduction model that includes brittle behaviour and viscous water-dependent creep flow laws. Our models show how the bound water distribution is not greatly influenced by the water migration scheme whereas the free water distribution is. We find that a water-dependent creep flow law results in a broader area of hydration in the mantle

  4. Interactions of opsonized immune complexes with whole blood cells: binding to erythrocytes restricts complex uptake by leucocyte populations

    DEFF Research Database (Denmark)

    Nielsen, C H; Svehag, S E; Marquart, H V

    1994-01-01

    -binding to granulocytes (PMN), monocytes and lymphocytes was inhibited by up to 46%, 61% and 48%, respectively, depending on the incubation time and the IC-concentration tested. The E-mediated inhibition of the binding to PMN was found to correlate with the average numbers of CR1 per E during the initial 15 min...... to the findings for PMN, the difference between IC-binding to monocytes in the absence and presence of E increased progressively over the 90 min observation period, suggesting that different mechanisms are involved in the late-phase IC uptake by monocytes and PMN. Lymphocytes were heterogeneous with respect to IC...... binding, the main contributors being B cells. E initially inhibited and then later enhanced the IC binding to lymphocytes, suggesting that E promote B cell uptake of C3d,g-covered IC via CR2. Our findings, that E can restrict the IC uptake by circulating leucocytes, and that an IC-induced degranulation...

  5. In vitro testing to diagnose venom allergy and monitor immunotherapy: a placebo-controlled, crossover trial.

    Science.gov (United States)

    Brown, S G A; Haas, M A; Black, J A; Parameswaran, A; Woods, G M; Heddle, R J

    2004-05-01

    In people with a history of sting allergy, only prior reaction severity and older age are known to predict subsequent reaction risk. Furthermore, no diagnostic test other than a deliberate sting challenge has been found to identify people in whom venom immunotherapy (VIT) has been unsuccessful. We aimed to assess the utility of a number of in vitro tests to diagnose venom allergy and to monitor immunotherapy. During a double-blind randomized placebo-controlled crossover trial of Myrmecia pilosula ant VIT the following venom-specific tests were performed at enrolment, and at completion of treatment prior to a diagnostic sting challenge; leucocyte stimulation index (SI), IL-4 production, IgE RAST, histamine release test (HRT), leukotriene release test (LRT) and basophil activation test (BAT). Intradermal venom skin testing (VST) was also performed at trial entry. Only VST and HRT identified those at risk of sting anaphylaxis in the placebo group. Although IgE RAST, leucocyte SI and IL-4 production, LRT and BAT all correlated well with intradermal VSTs, they did not predict sting challenge outcome. After successful VIT, venom-induced leucocyte IL-4 production tended to fall, whereas IgE RAST increased and a natural decline in HRT reactivity was reversed. A confounding seasonal affect on laboratory results was suspected. The HRT warrants further assessment for diagnosis of venom allergy. Uninformative performance of the commercially available LRT and BAT tests may be due to pre-incubation with IL-3. None of the tests evaluated appear to be reliable markers of successful VIT.

  6. A dual-docking microfluidic cell migration assay (D2-Chip) for testing neutrophil chemotaxis and the memory effect.

    Science.gov (United States)

    Yang, Ke; Wu, Jiandong; Xu, Guoqing; Xie, Dongxue; Peretz-Soroka, Hagit; Santos, Susy; Alexander, Murray; Zhu, Ling; Zhang, Michael; Liu, Yong; Lin, Francis

    2017-04-18

    Chemotaxis is a classic mechanism for guiding cell migration and an important topic in both fundamental cell biology and health sciences. Neutrophils are a widely used model to study eukaryotic cell migration and neutrophil chemotaxis itself can lead to protective or harmful immune actions to the body. While much has been learnt from past research about how neutrophils effectively navigate through a chemoattractant gradient, many interesting questions remain unclear. For example, while it is tempting to model neutrophil chemotaxis using the well-established biased random walk theory, the experimental proof was challenged by the cell's highly persistent migrating nature. A special experimental design is required to test the key predictions from the random walk model. Another question that has interested the cell migration community for decades concerns the existence of chemotactic memory and its underlying mechanism. Although chemotactic memory has been suggested in various studies, a clear quantitative experimental demonstration will improve our understanding of the migratory memory effect. Motivated by these questions, we developed a microfluidic cell migration assay (so-called dual-docking chip or D 2 -Chip) that can test both the biased random walk model and the memory effect for neutrophil chemotaxis on a single chip enabled by multi-region gradient generation and dual-region cell alignment. Our results provide experimental support for the biased random walk model and chemotactic memory for neutrophil chemotaxis. Quantitative data analyses provide new insights into neutrophil chemotaxis and memory by making connections to entropic disorder, cell morphology and oscillating migratory response.

  7. Family migration and relative earnings potentials

    DEFF Research Database (Denmark)

    Foged, Mette

    2016-01-01

    of husband centered migration. Couples are more likely to migrate if household earnings potential is disproportionally due to one partner, and families react equally strongly to a male and a female relative advantage in educational earnings potential. These results are driven by households with a strong......A unitarian model of family migration in which families may discount wives’ private gains is used to derive testable predictions regarding the type of couples that select into migrating. The empirical tests show that gender neutral family migration cannot be rejected against the alternative...

  8. Migration and AIDS.

    Science.gov (United States)

    1998-01-01

    This article presents the perspectives of UNAIDS and the International Organization for Migration (IOM) on migration and HIV/AIDS. It identifies research and action priorities and policy issues, and describes the current situation in major regions of the world. Migration is a process. Movement is enhanced by air transport, rising international trade, deregulation of trade practices, and opening of borders. Movements are restricted by laws and statutes. Denial to freely circulate and obtain asylum is associated with vulnerability to HIV infections. A UNAIDS policy paper in 1997 and IOM policy guidelines in 1988 affirm that refugees and asylum seekers should not be targeted for special measures due to HIV/AIDS. There is an urgent need to provide primary health services for migrants, voluntary counseling and testing, and more favorable conditions. Research is needed on the role of migration in the spread of HIV, the extent of migration, availability of health services, and options for HIV prevention. Research must be action-oriented and focused on vulnerability to HIV and risk taking behavior. There is substantial mobility in West and Central Africa, economic migration in South Africa, and nonvoluntary migration in Angola. Sex workers in southeast Asia contribute to the spread. The breakup of the USSR led to population shifts. Migrants in Central America and Mexico move north to the US where HIV prevalence is higher.

  9. Cytotoxicity and genotoxicity evaluation of organochalcogens in human leucocytes: a comparative study between ebselen, diphenyl diselenide, and diphenyl ditelluride.

    Science.gov (United States)

    Caeran Bueno, Diones; Meinerz, Daiane Francine; Allebrandt, Josiane; Waczuk, Emily Pansera; dos Santos, Danúbia Bonfanti; Mariano, Douglas Oscar Ceolin; Rocha, João Batista Teixeira

    2013-01-01

    Organochalcogens, particularly ebselen, have been used in experimental and clinical trials with borderline efficacy. (PhSe)2 and (PhTe)2 are the simplest of the diaryl dichalcogenides and share with ebselen pharmacological properties. In view of the concerns with the use of mammals in studies and the great number of new organochalcogens with potential pharmacological properties that have been synthesized, it becomes important to develop screening protocols to select compounds that are worth to be tested in vivo. This study investigated the possible use of isolated human white cells as a preliminary model to test organochalcogen toxicity. Human leucocytes were exposed to 5-50  μM of ebselen, (PhSe)2, or (PhTe)2. All compounds were cytotoxic (Trypan's Blue exclusion) at the highest concentration tested, and Ebselen was the most toxic. Ebselen and (PhSe)2 were genotoxic (Comet Assay) only at 50  μM, and (PhTe)2 at 5-50  μM. Here, the acute cytotoxicity did not correspond with in vivo toxicity of the compounds. But the genotoxicity was in the same order of the in vivo toxicity to mice. These results indicate that in vitro genotoxicity in white blood cells should be considered as an early step in the investigation of potential toxicity of organochalcogens.

  10. Testing the effects of basic numerical implementations of water migration on models of subduction dynamics

    Science.gov (United States)

    Quinquis, M. E. T.; Buiter, S. J. H.

    2014-06-01

    Subduction of oceanic lithosphere brings water into the Earth's upper mantle. Previous numerical studies have shown how slab dehydration and mantle hydration can impact the dynamics of a subduction system by allowing a more vigorous mantle flow and promoting localisation of deformation in the lithosphere and mantle. The depths at which dehydration reactions occur in the hydrated portions of the slab are well constrained in these models by thermodynamic calculations. However, computational models use different numerical schemes to simulate the migration of free water. We aim to show the influence of the numerical scheme of free water migration on the dynamics of the upper mantle and more specifically the mantle wedge. We investigate the following three simple migration schemes with a finite-element model: (1) element-wise vertical migration of free water, occurring independent of the flow of the solid phase; (2) an imposed vertical free water velocity; and (3) a Darcy velocity, where the free water velocity is a function of the pressure gradient caused by the difference in density between water and the surrounding rocks. In addition, the flow of the solid material field also moves the free water in the imposed vertical velocity and Darcy schemes. We first test the influence of the water migration scheme using a simple model that simulates the sinking of a cold, hydrated cylinder into a dry, warm mantle. We find that the free water migration scheme has only a limited impact on the water distribution after 1 Myr in these models. We next investigate slab dehydration and mantle hydration with a thermomechanical subduction model that includes brittle behaviour and viscous water-dependent creep flow laws. Our models demonstrate that the bound water distribution is not greatly influenced by the water migration scheme whereas the free water distribution is. We find that a bound water-dependent creep flow law results in a broader area of hydration in the mantle wedge, which

  11. Recovery Migration After Hurricanes Katrina and Rita: Spatial Concentration and Intensification in the Migration System.

    Science.gov (United States)

    Curtis, Katherine J; Fussell, Elizabeth; DeWaard, Jack

    2015-08-01

    Changes in the human migration systems of the Gulf of Mexico coastline counties affected by Hurricanes Katrina and Rita provide an example of how climate change may affect coastal populations. Crude climate change models predict a mass migration of "climate refugees," but an emerging literature on environmental migration suggests that most migration will be short-distance and short-duration within existing migration systems, with implications for the population recovery of disaster-stricken places. In this research, we derive a series of hypotheses on recovery migration predicting how the migration system of hurricane-affected coastline counties in the Gulf of Mexico was likely to have changed between the pre-disaster and the recovery periods. We test these hypotheses using data from the Internal Revenue Service on annual county-level migration flows, comparing the recovery period migration system (2007-2009) with the pre-disaster period (1999-2004). By observing county-to-county ties and flows, we find that recovery migration was strong: the migration system of the disaster-affected coastline counties became more spatially concentrated, while flows within it intensified and became more urbanized. Our analysis demonstrates how migration systems are likely to be affected by the more intense and frequent storms anticipated by climate change scenarios, with implications for the population recovery of disaster-affected places.

  12. Assessment of the risk to patients from the labelling of leucocytes with indium-111

    International Nuclear Information System (INIS)

    Edwards, A.A.; Lloyd, D.C.

    1986-01-01

    Indium-111 oxine is used in diagnostic nuclear medicine to label leucocytes. A typical procedure might be to label white cells in 50 ml of blood with about 500 μCi (∼ 20 MBq) of indium-111 and return them to the body. Both theoretical and experimental information from measurements of chromosome aberrations in lymphocytes show that the labelled cells receive doses of some tens of grays, mostly delivered within one to two weeks. Much of the dose is due to short range Auger electrons. The doses to organs of the body due to circulating labelled cells are much lower. The risk to the patient thus has two components, due to the low dose irradiation of body organs and the localized high dose to the labelled cells. The former is estimated using the concept of effective dose equivalent as recommended by ICRP. An effective dose equivalent of 2 x 10 -2 Sv x mCi -1 for the above procedure was calculated making use of recent data on the distribution of the label within the body. The resulting risk of inducing a fatal cancer is calculated as about 3 x 10 -4 mCi -1 . Attempts to evaluate the risk of leukemia and lymphatic cancer due to direct irradiation of labelled leucocytes are more difficult. If cellular doses are as high as 50 Gy, cell killing can be used to argue that the risk is much lower than the whole-body risk. For lower cellular doses an argument based on the fraction of cells irradiated is used and the risk due to the labelled cells appears to be two orders of magnitude lower than the whole-body risk. 30 references, 1 figure, 3 tables

  13. Nordic Migration and Integration Research

    OpenAIRE

    Pyrhönen, Niko; Martikainen, Tuomas; Leinonen, Johanna

    2017-01-01

    EXECUTIVE SUMMARY Migration and integration are currently highly contentious topics in political, public and scientific arenas, and will remain so in the near future. However, many common migration-related prejudices and inefficien¬cies in the integration of the migrant population are due to the lack of sound, tested and accessible scientific research. Therefore, the study of migration – by developing basic research and by properly resourcing novel methodological approaches and interventions ...

  14. ''In situ'' migration tests at the Berrocal site with conservative isotopic tracers: laboratory and field results from phase I of the project

    International Nuclear Information System (INIS)

    D'Alessandro, M.; Mousty, F.; Guimera, J.; Yllera de Llano, A.

    1996-01-01

    Cross-hole migration tests were performed between two boreholes connected by a fracture in the granite aquifer of the El Berrocal site. The suitability of a natural isotopic tracer (''79BR) as hydrological marker of groundwater movement, was evaluated on the basis of laboratory and field tests. Small scale infiltration experiments with granite cored columns and repacked columns of crushed granite showed that the change of the natural isotopic ratio ''79Br/''81Br with time can be used to monitor the tracer breakthrough. Comparison was made with other non-sorbing tracers, such as tritiated water, chloride and iodide. The difference in travel time of halides was ascribed to anion exclusion and ion size effects. The in-situ migration test demonstrated the feasibility of the described technique for monitoring the groundwater movement without altering the geochemistry of the site. The following approach has been chosen: 1) a first preliminary test demonstrating the feasibility of using the enriched isotopic tracer technique for ''in-situ''tests. 2) Preliminary assessment of the parameters necessary to plan a radial-flow migration test directed to characterize the permeable system through the definition of the hydrodynamic parameters of the fracture. (Author)

  15. Probabilistic migration modelling focused on functional barrier efficiency and low migration concepts in support of risk assessment.

    Science.gov (United States)

    Brandsch, Rainer

    2017-10-01

    Migration modelling provides reliable migration estimates from food-contact materials (FCM) to food or food simulants based on mass-transfer parameters like diffusion and partition coefficients related to individual materials. In most cases, mass-transfer parameters are not readily available from the literature and for this reason are estimated with a given uncertainty. Historically, uncertainty was accounted for by introducing upper limit concepts first, turning out to be of limited applicability due to highly overestimated migration results. Probabilistic migration modelling gives the possibility to consider uncertainty of the mass-transfer parameters as well as other model inputs. With respect to a functional barrier, the most important parameters among others are the diffusion properties of the functional barrier and its thickness. A software tool that accepts distribution as inputs and is capable of applying Monte Carlo methods, i.e., random sampling from the input distributions of the relevant parameters (i.e., diffusion coefficient and layer thickness), predicts migration results with related uncertainty and confidence intervals. The capabilities of probabilistic migration modelling are presented in the view of three case studies (1) sensitivity analysis, (2) functional barrier efficiency and (3) validation by experimental testing. Based on the predicted migration by probabilistic migration modelling and related exposure estimates, safety evaluation of new materials in the context of existing or new packaging concepts is possible. Identifying associated migration risk and potential safety concerns in the early stage of packaging development is possible. Furthermore, dedicated material selection exhibiting required functional barrier efficiency under application conditions becomes feasible. Validation of the migration risk assessment by probabilistic migration modelling through a minimum of dedicated experimental testing is strongly recommended.

  16. Synthetic seismic monitoring using reverse-time migration and Kirchhoff migration for CO2 sequestration in Korea

    Science.gov (United States)

    Kim, W.; Kim, Y.; Min, D.; Oh, J.; Huh, C.; Kang, S.

    2012-12-01

    During last two decades, CO2 sequestration in the subsurface has been extensively studied and progressed as a direct tool to reduce CO2 emission. Commercial projects such as Sleipner, In Salah and Weyburn that inject more than one million tons of CO2 per year are operated actively as well as test projects such as Ketzin to study the behavior of CO2 and the monitoring techniques. Korea also began the CCS (CO2 capture and storage) project. One of the prospects for CO2 sequestration in Korea is the southwestern continental margin of Ulleung basin. To monitor the behavior of CO2 underground for the evaluation of stability and safety, several geophysical monitoring techniques should be applied. Among various geophysical monitoring techniques, seismic survey is considered as the most effective tool. To verify CO2 migration in the subsurface more effectively, seismic numerical simulation is an essential process. Furthermore, the efficiency of the seismic migration techniques should be investigated for various cases because numerical seismic simulation and migration test help us accurately interpret CO2 migration. In this study, we apply the reverse-time migration and Kirchhoff migration to synthetic seismic monitoring data generated for the simplified model based on the geological structures of Ulleung basin in Korea. Synthetic seismic monitoring data are generated for various cases of CO2 migration in the subsurface. From the seismic migration images, we can investigate CO2 diffusion patterns indirectly. From seismic monitoring simulation, it is noted that while the reverse-time migration generates clear subsurface images when subsurface structures are steeply dipping, Kirchhoff migration has an advantage in imaging horizontal-layered structures such as depositional sediments appearing in the continental shelf. The reverse-time migration and Kirchhoff migration present reliable subsurface images for the potential site characterized by stratigraphical traps. In case of

  17. Recovery Migration after Hurricanes Katrina and Rita: Spatial Concentration and Intensification in the Migration System

    Science.gov (United States)

    Fussell, Elizabeth; DeWaard, Jack

    2015-01-01

    Changes in the human migration systems of Hurricane Katrina- and Rita-affected Gulf of Mexico coastline counties provide an example of how climate change may affect coastal populations. Crude climate change models predict a mass migration of “climate refugees,” but an emerging literature on environmental migration suggests most migration will be short-distance and short-duration within existing migration systems, with implications for the population recovery of disaster-struck places. In this research, we derive a series of hypotheses on recovery migration predicting how the migration system of hurricane-affected coastline counties in the Gulf of Mexico was likely to have changed between the pre-disaster and the recovery periods. We test these hypotheses using data from the Internal Revenue Service on annual county-level migration flows, comparing the recovery period migration system (2007–2009) to the pre-disaster period (1999–2004). By observing county-to-county ties and flows we find that recovery migration was strong, as the migration system of the disaster-affected coastline counties became more spatially concentrated while flows within it intensified and became more urbanized. Our analysis demonstrates how migration systems are likely to be affected by the more intense and frequent storms anticipated by climate change scenarios with implications for the population recovery of disaster-affected places. PMID:26084982

  18. [Urban employment and internal migration in Peru].

    Science.gov (United States)

    Cotlear, D

    1984-06-01

    The relationship between internal migration and employment problems in Peru is examined. The author argues that regional differences in income distribution are the primary causes of migration, particularly to urban areas. A model of the migration process is developed and tested using data from official sources, surveys, and the published literature.

  19. Partial diel migration: A facultative migration underpinned by long-term inter-individual variation.

    Science.gov (United States)

    Harrison, Philip M; Gutowsky, Lee F G; Martins, Eduardo G; Patterson, David A; Cooke, Steven J; Power, Michael

    2017-09-01

    The variations in migration that comprise partial diel migrations, putatively occur entirely as a consequence of behavioural flexibility. However, seasonal partial migrations are increasingly recognised to be mediated by a combination of reversible plasticity in response to environmental variation and individual variation due to genetic and environmental effects. Here, we test the hypothesis that while partial diel migration heterogeneity occurs primarily due to short-term within-individual flexibility in behaviour, long-term individual differences in migratory behaviour also underpin this migration variation. Specifically, we use a hierarchical behavioural reaction norm approach to partition within- and among-individual variation in depth use and diel plasticity in depth use, across short- and long-term time-scales, in a group of 47 burbot (Lota lota) tagged with depth-sensing acoustic telemetry transmitters. We found that within-individual variation at the among-dates-within-seasons and among-seasons scale, explained the dominant proportion of phenotypic variation. However, individuals also repeatedly differed in their expression of migration behaviour over the 2 year study duration. These results reveal that diel migration variation occurs primarily due to short-term within-individual flexibility in depth use and diel migration behaviour. However, repeatable individual differences also played a key role in mediating partial diel migration. These findings represent a significant advancement of our understanding of the mechanisms generating the important, yet poorly understood phenomena of partial diel migration. Moreover, given the pervasive occurrence of diel migrations across aquatic taxa, these findings indicate that individual differences have an important, yet previously unacknowledged role in structuring the temporal and vertical dynamics of aquatic ecosystems. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

  20. A short leucocyte telomere length is associated with development of insulin resistance

    DEFF Research Database (Denmark)

    Verhulst, Simon; Dalgård, Christine; Labat, Carlos

    2016-01-01

    AIMS/HYPOTHESIS: A number of studies have shown that leucocyte telomere length (LTL) is inversely associated with insulin resistance and type 2 diabetes mellitus. The aim of the present longitudinal cohort study, utilising a twin design, was to assess whether shorter LTL predicts insulin resistance...... and insulin resistance over an average of 12 years were performed in a subset of the Registry consisting of 338 (184 monozygotic and 154 dizygotic) same-sex twin pairs. RESULTS: Age at baseline examination was 37.4 ± 9.6 (mean ± SD) years. Baseline insulin resistance was not associated with age......-dependent changes in LTL (attrition) over the follow-up period, whereas baseline LTL was associated with changes in insulin resistance during this period. The shorter the LTL at baseline, the more pronounced was the increase in insulin resistance over the follow-up period (p 

  1. Plutonium Particle Migration in the Shallow Vadose Zone: The Nevada Test Site as an Analog Site

    Science.gov (United States)

    Hunt, J. R.; Smith, D. K.

    2004-12-01

    The upper meter of the vadose zone in desert environments is the horizon where wastes have been released and human exposure is determined through dermal, inhalation, and food uptake pathways. This region is also characterized by numerous coupled processes that determine contaminant transport, including precipitation infiltration, evapotranspiration, daily and annual temperature cycling, dust resuspension, animal burrowing, and geochemical weathering reactions. While there is considerable interest in colloidal transport of minerals, pathogenic organisms, and contaminants in the vadose zone, there are limited field sites where the actual occurrence of contaminant migration can be quantified over the appropriate spatial and temporal scales of interest. At the US Department of Energy Nevada Test Site, there have been numerous releases of radionuclides since the 1950's that have become field-scale tracer tests. One series of tests was the four safety shots conducted in an alluvial valley of Area 11 in the 1950's. These experiments tested the ability of nuclear materials to survive chemical explosions without initiating fission reactions. Four above-ground tests were conducted and they released plutonium and uranium on the desert valley floor with only one of the tests undergoing some fission. Shortly after the tests, the sites were surveyed for radionuclide distribution on the land surface using aerial surveys and with depth. Additional studies were conducted in the 1970's to better understand the fate of plutonium in the desert that included studies of depth distribution and dust resuspension. More recently, plutonium particle distribution in the soil profile was detected using autoradiography. The results to date demonstrate the vertical migration of plutonium particles to depths in excess of 30 cm in this arid vadose zone. While plutonium migration at the Nevada Test Site has been and continues to be a concern, these field experiments have become analog sites for the

  2. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai; Schuster, Gerard T.

    2016-01-01

    Elastic least-squares reverse time migration (LSRTM) is used to invert synthetic particle-velocity data and crosswell pressure field data. The migration images consist of both the P- and Svelocity perturbation images. Numerical tests on synthetic and field data illustrate the advantages of elastic LSRTM over elastic reverse time migration (RTM). In addition, elastic LSRTM images are better focused and have better reflector continuity than do the acoustic LSRTM images.

  3. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai

    2016-09-06

    Elastic least-squares reverse time migration (LSRTM) is used to invert synthetic particle-velocity data and crosswell pressure field data. The migration images consist of both the P- and Svelocity perturbation images. Numerical tests on synthetic and field data illustrate the advantages of elastic LSRTM over elastic reverse time migration (RTM). In addition, elastic LSRTM images are better focused and have better reflector continuity than do the acoustic LSRTM images.

  4. Is there a step-wise migration in Nigeria? A case study of the migrational histories of migrants in Lagos.

    Science.gov (United States)

    Afolayan, A A

    1985-09-01

    "The paper sets out to test whether or not the movement pattern of people in Nigeria is step-wise. It examines the spatial order in the country and the movement pattern of people. It then analyzes the survey data and tests for the validity of step-wise migration in the country. The findings show that step-wise migration cannot adequately describe all the patterns observed." The presence of large-scale circulatory migration between rural and urban areas is noted. Ways to decrease the pressure on Lagos by developing intermediate urban areas are considered. excerpt

  5. Imaging near-surface heterogeneities by natural migration of backscattered surface waves: Field data test

    KAUST Repository

    Liu, Zhaolun; AlTheyab, Abdullah; Hanafy, Sherif M.; Schuster, Gerard T.

    2017-01-01

    We have developed a methodology for detecting the presence of near-surface heterogeneities by naturally migrating backscattered surface waves in controlled-source data. The near-surface heterogeneities must be located within a depth of approximately one-third the dominant wavelength λ of the strong surface-wave arrivals. This natural migration method does not require knowledge of the near-surface phase-velocity distribution because it uses the recorded data to approximate the Green’s functions for migration. Prior to migration, the backscattered data are separated from the original records, and the band-passed filtered data are migrated to give an estimate of the migration image at a depth of approximately one-third λ. Each band-passed data set gives a migration image at a different depth. Results with synthetic data and field data recorded over known faults validate the effectiveness of this method. Migrating the surface waves in recorded 2D and 3D data sets accurately reveals the locations of known faults. The limitation of this method is that it requires a dense array of receivers with a geophone interval less than approximately one-half λ.

  6. Imaging near-surface heterogeneities by natural migration of backscattered surface waves: Field data test

    KAUST Repository

    Liu, Zhaolun

    2017-03-06

    We have developed a methodology for detecting the presence of near-surface heterogeneities by naturally migrating backscattered surface waves in controlled-source data. The near-surface heterogeneities must be located within a depth of approximately one-third the dominant wavelength λ of the strong surface-wave arrivals. This natural migration method does not require knowledge of the near-surface phase-velocity distribution because it uses the recorded data to approximate the Green’s functions for migration. Prior to migration, the backscattered data are separated from the original records, and the band-passed filtered data are migrated to give an estimate of the migration image at a depth of approximately one-third λ. Each band-passed data set gives a migration image at a different depth. Results with synthetic data and field data recorded over known faults validate the effectiveness of this method. Migrating the surface waves in recorded 2D and 3D data sets accurately reveals the locations of known faults. The limitation of this method is that it requires a dense array of receivers with a geophone interval less than approximately one-half λ.

  7. Limitations in the use of indium-111-oxine-labeled leucocytes for the diagnosis of occult infection in children

    Energy Technology Data Exchange (ETDEWEB)

    Haentjens, M.; Piepsz, A.; Perlmutter-Cremer, N.; Schell-Frederick, E.; Fruehling, J.

    1987-02-01

    Fifteen children underwent scintigraphy with indium 111 (/sup 111/In)-labeled white blood cells (WBC) for the detection of a local suppuration. The procedure generally contributed to a correct diagnosis. False negative results were observed in 5 children, but in two of them positive foci were also present. The missed lesions were 2 liver abscesses, 1 lung abscess, foci of osteomyelitis and 1 pericarditis. Two cases of chronic granulomatous disease are presented in which increased leucocyte accumulation was not observed in proven instances of infection.

  8. Cytotoxicity and Genotoxicity Evaluation of Organochalcogens in Human Leucocytes: A Comparative Study between Ebselen, Diphenyl Diselenide, and Diphenyl Ditelluride

    Directory of Open Access Journals (Sweden)

    Diones Caeran Bueno

    2013-01-01

    Full Text Available Organochalcogens, particularly ebselen, have been used in experimental and clinical trials with borderline efficacy. (PhSe2 and (PhTe2 are the simplest of the diaryl dichalcogenides and share with ebselen pharmacological properties. In view of the concerns with the use of mammals in studies and the great number of new organochalcogens with potential pharmacological properties that have been synthesized, it becomes important to develop screening protocols to select compounds that are worth to be tested in vivo. This study investigated the possible use of isolated human white cells as a preliminary model to test organochalcogen toxicity. Human leucocytes were exposed to 5–50 μM of ebselen, (PhSe2, or (PhTe2. All compounds were cytotoxic (Trypan’s Blue exclusion at the highest concentration tested, and Ebselen was the most toxic. Ebselen and (PhSe2 were genotoxic (Comet Assay only at 50 μM, and (PhTe2 at 5–50 μM. Here, the acute cytotoxicity did not correspond with in vivo toxicity of the compounds. But the genotoxicity was in the same order of the in vivo toxicity to mice. These results indicate that in vitro genotoxicity in white blood cells should be considered as an early step in the investigation of potential toxicity of organochalcogens.

  9. 111Indium-labelled leucocyte scintigraphy in the diagnosis of inflammatory disease - first results

    International Nuclear Information System (INIS)

    Rovekamp, M.H.; Hardeman, M.R.; Schoot, J.B. van der; Belfer, A.J.

    1981-01-01

    In 61 patients, 66 scans were performed with 111 In-labelled autologous leucocytes to evaluate this method in the diagnosis of inflammatory disease. All scintigraphic results were compared with clinical, operative or postmortem findings. In the first 20 examinations in 19 patients, 2 scintigrams were true positive, 9 true negative and none false positive, whereas 9 scintigrams had to be considered as false negative. These false negative results were probably due to loss of viability of the labelled cells. A modified labelling technique, in which a much lower concentration of oxine was used, was employed for a further 46 examinations in 42 patients. Twenty-four scintigrams were true positive and 22 true negative, while no false positive or false negative results were observed. These results suggest that this modified technique is useful in the diagnosis of inflammatory disease. (author)

  10. Leucocyte esterase dip-stick test as a point-of-care diagnostic for urogenital chlamydia in male patients: A multi-center evaluation in two STI outpatient clinics in Paramaribo and Amsterdam

    Directory of Open Access Journals (Sweden)

    Menne Bartelsman

    2016-11-01

    Full Text Available Abstract Background Point-of-care (POC tests are an important strategy to address the epidemic of sexually transmitted infections (STIs. The leucocyte esterase test (LET can be used as a POC test for chlamydia. The aim of this study was to determine the diagnostic accuracy of the LET to detect urogenital chlamydia among men at STI clinics in Paramaribo, Suriname and Amsterdam, the Netherlands. Methods Recruitment of patients took place in 2008–2010 in Suriname and in 2009–2010 in the Netherlands. Urine of patients was examined with the LET. The reference test was a nucleic acid amplification test (NAAT. Results We included 412 patients in Suriname and 645 in the Netherlands. Prevalence of chlamydia in Suriname and the Netherlands was respectively 22.8 and 13.6 %. The sensitivity of the LET was 92.6 % (95 % CI = 85.3–97.0 and 77.3 % (95 % CI = 67.1–85.5 respectively, the specificity was 38.1 % (95 % CI = 32.7–43.6 % and 58.1 % (95 % CI = 53.9–62.3 respectively. The positive predictive value was 30.6 % (95 % CI = 27.3–36.4 and 22.6 % (95 % CI = 18.0–27.7 respectively and the negative predictive value was 94.5 % (95 % CI = 89.1–97.8 and 94.2 % (95 % CI = 91.1–96.4 respectively. The kappa was respectively 0.179 and 0.176. Conclusions To diagnose urogenital chlamydia in men the LET performs poorly. It has a high negative but low positive predictive value. If the LET result is negative, chlamydia is accurately excluded, yet a positive result has a low predictive value. Whether the advantages of direct management based on LET outweigh the disadvantages of overtreatment is a subject for further studies.

  11. Migration of 2-butoxyethyl acetate from polycarbonate infant feeding bottles

    DEFF Research Database (Denmark)

    Petersen, Jens Højslev; Lund, K.H.

    2003-01-01

    An enforcement campaign was carried out to assess the migration of 2-butoxyethyl acetate (2-BEA) from polycarbonate infant feeding bottles intended for repeated use. Migration was measured by three successive migration tests into two of the European Union official food simulants: distilled water......-BEA was found from eight of 12 bottles. However, migration above the target value of 0.33 mg kg(-1) was not observed in the third decisive test from any of the 12 different brands of polycarbonate feeding bottles. A migration of between 0.05 and 0.26 mg kg(-1) from seven of 12 bottles was measured...

  12. Social networks, migration, and HIV testing among Latinos in a new immigrant destination: Insights from a qualitative study.

    Science.gov (United States)

    Barrington, Clare; Gandhi, Anisha; Gill, Adrienne; Villa Torres, Laura; Brietzke, Maria Priscila; Hightow-Weidman, Lisa

    2017-12-03

    Latinos in the U.S. are disproportionately affected by HIV and are more likely than non-Latinos to present with a late diagnosis, which delays engagement in HIV care and treatment. Social networks may provide normative influence and social support for HIV testing, but a contextualised understanding of networks is needed in order to maximise these social resources. We conducted qualitative interviews with foreign-born Latino men and transgender women (n = 17) in a new immigrant destination to explore their social networks. Most participants described having smaller social networks after migrating. Networks included both local and transnational ties, but most participants had few close ties. Contextual factors including stigma and geographic dispersion limited the re-construction of networks with close ties after migration. HIV testing was not a common topic of discussion with social network ties. Efforts to improve early uptake of HIV testing among Latino immigrants may benefit from engaging with social networks, but such efforts need to address how the context in which networks operate enables access to testing.

  13. International Migration with Heterogeneous Agents: Theory and Evidence

    DEFF Research Database (Denmark)

    Schröder, Philipp J.H.; Brücker, Herbert

    Temporary migration, though empirically relevant, is often ignored in formal models. This paper proposes a migration model with heterogeneous agents and persistent cross country income differentials that features temporary migration. In equilibrium there exists a positive relation between the stock...... of migrants and the income differential, while the net migration flow becomes zero. Consequently, existing empirical migration models, estimating net migration flows, instead of stocks, may be misspecified. This suspicion appears to be confirmed by our investigation of the cointegration relationships...... of German migration stocks and flows since 1967. We find that (i) panel-unit root tests reject the hypothesis that migration flows and the explanatory variables are integrated of the same order, while migration stocks and the explanatory variables are all I(1) variables, and (ii) the hypothesis...

  14. Grimsel test site: preparation and performance of migration experiments with radioisotopes of sodium, strontium and iodine

    International Nuclear Information System (INIS)

    Eikenberg, J.; Hoehn, E.; Fierz, T.; Frick, U.

    1994-09-01

    During 1991 four migration experiments with 22 Na (run 50), 24 Na (run 48), 85 Sr (run 50) and 123 I (run 47,49) were carried out in the migration fracture at the Grimsel Test Site (GTS) using a two-well injection -extraction technique (dipole configuration). All tests were accompanied by simultaneous injection of Na-fluorescein (uranine) as a conservative tracer. The dipole flow field was installed between boreholes 86.004 (injection well) and 87.006 (extraction well). The extraction flow rate was always held constant at 150 mL/min, while two different injection flow rates of 50 mL/min (runs 47,48) and 10 mL/min (runs 49, 50) were chosen to vary the flow field geometry. These exercises advance the transport model studies to evaluate important fracture specific parameters. Prior to the field tests with radiotracers of cationic Na + and Sr 2+ , the potential sorption of these elements onto equipment materials such as tubing, pumps, detectors was investigated in the field rock laboratory under identical flow conditions and test arrangements as for the fracture tests. In contrast to Na + , bivalent Sr 2+ sorbed strongly, especially onto stainless steel tubing surrounding the NaI scintillation counters used for on-line γ-detection of the radiotracers. To minimize sorption of Sr 2+ on equipment, all exposed materials were then completely replaced by PRFE (Teflon). Further tests revealed that this material proved to be chemically inert with respect to Na + and Sr 2+ . Calibration of the field data was made by check laboratory analyses of water samples. The detection limits of all tracers were below 0.05 Bp/mL. (author) 38 figs., 13 tabs., refs

  15. A ppendicitis with Positive Ultrasound and its Relation to Total and Differential Leucocytic Count

    International Nuclear Information System (INIS)

    Saleh, G.M.; Sabek, E.A.S.; Elessiely, E.S.; Ibrahim, E.M.

    2016-01-01

    Background:The most common cause of acute surgical abdomen is acute appendicitis and the most commonly done emergency surgery is appendectomy. Although a battery of tests and different scoring methods are available for diagnosis of acute appendicitis, it is very difficult to prevent negative explorations for appendicectomy (15 - 30%). None of the tests has satisfactory Sensitivity and specificity that can be relied upon. Objectives: The aim of the present study was to evaluate the role of total and differential leukocyte count, and ultrasonography (USG) of abdomen in diagnosing acute appendicitis and reducing the rates of negative appendicectomies and to prevent complications like perforation, peritonitis, and the longer the delay between diagnosis and surgery, the more likely is the perforation leading to peritonitis. In addition, emphasis was given to whether combining the investigations for the same patient would improve the diagnostic accuracy. Materials and Methods : A total of 76 clinically diagnosed patients of acute appendicitis, posted for emergency appendicectomy were included in the study in General Surgery Department of EL-Salam Hospital. This study was conducted in the period October 2012 to September 2013. Preoperatively blood tests for, total leukocyte count, differential leukocyte count(DLC) and USG abdomen were done. All patients were subjected to histological examination postoperatively, which was taken as the gold standard. The three investigations results were correlated with histopathological examination reports to evaluate their role in diagnosis of acute appendicitis. Results: In the present study, the US has the highest sensitivity and specificity (90%, 80%) followed by Total leucocyte count (87.5%, 90%), white Neutrophil count (78.75%, 80%). Combining US and WBC count increases the sensitivity and specificity of the tests (96.25%, 80%). Conclusion: US contains important diagnostic information and hence should always be included in the

  16. Testing thermal gradient driving force for grain boundary migration using molecular dynamics simulations

    International Nuclear Information System (INIS)

    Bai, Xian-Ming; Zhang, Yongfeng; Tonks, Michael R.

    2015-01-01

    Strong thermal gradients in low-thermal-conductivity ceramics may drive extended defects, such as grain boundaries and voids, to migrate in preferential directions. In this work, molecular dynamics simulations are conducted to study thermal gradient driven grain boundary migration and to verify a previously proposed thermal gradient driving force equation, using uranium dioxide as a model system. It is found that a thermal gradient drives grain boundaries to migrate up the gradient and the migration velocity increases under a constant gradient owing to the increase in mobility with temperature. Different grain boundaries migrate at very different rates due to their different intrinsic mobilities. The extracted mobilities from the thermal gradient driven simulations are compared with those calculated from two other well-established methods and good agreement between the three different methods is found, demonstrating that the theoretical equation of the thermal gradient driving force is valid, although a correction of one input parameter should be made. The discrepancy in the grain boundary mobilities between modeling and experiments is also discussed.

  17. Laboratory and field tests for radionuclide migration and high flow paths in clay

    International Nuclear Information System (INIS)

    Bourke, P.J.; Jefferies, N.L.; Lineham, T.R.; Nesirky, P.

    1991-01-01

    Two investigations have been undertaken in this programme. The principal investigation was at Culham Laboratory, England, where water flow within the Kimmeridge clay was measured. A subsidiary investigation at SCK/CEN was undertaken at the Underground Research Laboratory SCK/CEN Mol, Belgium, where an in situ measurement of solute transport by diffusion was attempted. The in situ migration experiment at the Underground Research Laboratory at SCK/CEN Mol, Belgium, was unsuccessful, due to problems with the engineering installation. These difficulties caused significant disturbance to the Boom clay which was to be tested. Nevertheless the laboratory test proved the feasibility of the experiment. The field measurements at Culham Laboratory, Oxfordshire, were completed with the flow testing of a very silty clay horizon in the Kimmeridge clay. This layer was proved to be laterally continuous after drilling three exploratory boreholes. The hydraulic conductivity of the layer was ≥ 10 -8 ms -1 and comparative tests in the clay showed the conductivity of the clay to be at least 50 times less. 12 figs

  18. Testing an emerging paradigm in migration ecology shows surprising differences in efficiency between flight modes.

    Directory of Open Access Journals (Sweden)

    Adam E Duerr

    Full Text Available To maximize fitness, flying animals should maximize flight speed while minimizing energetic expenditure. Soaring speeds of large-bodied birds are determined by flight routes and tradeoffs between minimizing time and energetic costs. Large raptors migrating in eastern North America predominantly glide between thermals that provide lift or soar along slopes or ridgelines using orographic lift (slope soaring. It is usually assumed that slope soaring is faster than thermal gliding because forward progress is constant compared to interrupted progress when birds pause to regain altitude in thermals. We tested this slope-soaring hypothesis using high-frequency GPS-GSM telemetry devices to track golden eagles during northbound migration. In contrast to expectations, flight speed was slower when slope soaring and eagles also were diverted from their migratory path, incurring possible energetic costs and reducing speed of progress towards a migratory endpoint. When gliding between thermals, eagles stayed on track and fast gliding speeds compensated for lack of progress during thermal soaring. When thermals were not available, eagles minimized migration time, not energy, by choosing energetically expensive slope soaring instead of waiting for thermals to develop. Sites suited to slope soaring include ridges preferred for wind-energy generation, thus avian risk of collision with wind turbines is associated with evolutionary trade-offs required to maximize fitness of time-minimizing migratory raptors.

  19. Testing an emerging paradigm in migration ecology shows surprising differences in efficiency between flight modes.

    Science.gov (United States)

    Duerr, Adam E; Miller, Tricia A; Lanzone, Michael; Brandes, Dave; Cooper, Jeff; O'Malley, Kieran; Maisonneuve, Charles; Tremblay, Junior; Katzner, Todd

    2012-01-01

    To maximize fitness, flying animals should maximize flight speed while minimizing energetic expenditure. Soaring speeds of large-bodied birds are determined by flight routes and tradeoffs between minimizing time and energetic costs. Large raptors migrating in eastern North America predominantly glide between thermals that provide lift or soar along slopes or ridgelines using orographic lift (slope soaring). It is usually assumed that slope soaring is faster than thermal gliding because forward progress is constant compared to interrupted progress when birds pause to regain altitude in thermals. We tested this slope-soaring hypothesis using high-frequency GPS-GSM telemetry devices to track golden eagles during northbound migration. In contrast to expectations, flight speed was slower when slope soaring and eagles also were diverted from their migratory path, incurring possible energetic costs and reducing speed of progress towards a migratory endpoint. When gliding between thermals, eagles stayed on track and fast gliding speeds compensated for lack of progress during thermal soaring. When thermals were not available, eagles minimized migration time, not energy, by choosing energetically expensive slope soaring instead of waiting for thermals to develop. Sites suited to slope soaring include ridges preferred for wind-energy generation, thus avian risk of collision with wind turbines is associated with evolutionary trade-offs required to maximize fitness of time-minimizing migratory raptors.

  20. Brine migration in hot-pressed polycrystalline sodium chloride

    International Nuclear Information System (INIS)

    Biggers, J.V.; Dayton, G.O.

    1982-12-01

    This report describes experiments designed to provide data on brine migration in polycrystalline salt. Polycrystalling samples of various grain sizes, density, and purity were prepared from several commercial-grade salts by hot-pressing. Three distinct experimental set-ups were used to place salt billets in an induced thermal gradient in contact with brine source. The test designs varied primarily in the way in which the thermal gradient was applied and monitored and the way in which brine migration was determined. All migration was in enclosed vessels which precluded visual observation of brine movement through the microstructure. Migration velocities were estimated either by the timed appearance of brine at the hot face of the sample, or by determination of the penetration distance of migration artifacts in the microstructure after tests of fixed duration. For various reasons both of these methods were subject to a large degree of error. Our results suggest, however, that the migration velocity in dense polycrystalline salt may be at least an order of magnitude greater than that suggested by single-crystal experiments. Microstructural analysis shows that brine prefers to migrate along paths of high crystalline activity such as grain and subgrain boundaries and is dispersed rather quickly in the microstructure. A series of tests were performed using various types of tracers in brine in order to flag migration paths and locate brine in the microstructure more decisively. These attempts failed and it appears that only the aqueous portion of the brine moves through the microstructure with the dissolved ions being lost and replaced rather quickly. This suggests the use of deuterium as a tracer in future work

  1. Return Migration as Failure or Success?: The Determinants of Return Migration Intentions Among Moroccan Migrants in Europe.

    Science.gov (United States)

    de Haas, Hein; Fokkema, Tineke; Fihri, Mohamed Fassi

    Different migration theories generate competing hypotheses with regard to determinants of return migration. While neoclassical migration theory associates migration to the failure to integrate at the destination, the new economics of labour migration sees return migration as the logical stage after migrants have earned sufficient assets and knowledge and to invest in their origin countries. The projected return is then likely to be postponed for sustained or indefinite periods if integration is unsuccessful. So, from an indication or result of integration failure return is rather seen as a measure of success. Drawing on recent survey data ( N  = 2,832), this article tests these hypotheses by examining the main determinants of return intention among Moroccan migrants across Europe. The results indicate that structural integration through labour market participation, education and the maintenance of economic and social ties with receiving countries do not significantly affect return intentions. At the same time, investments and social ties to Morocco are positively related, and socio-cultural integration in receiving countries is negatively related to return migration intentions. The mixed results corroborate the idea that there is no uniform process of (return) migration and that competing theories might therefore be partly complementary.

  2. Aspects of general linear modelling of migration.

    Science.gov (United States)

    Congdon, P

    1992-01-01

    "This paper investigates the application of general linear modelling principles to analysing migration flows between areas. Particular attention is paid to specifying the form of the regression and error components, and the nature of departures from Poisson randomness. Extensions to take account of spatial and temporal correlation are discussed as well as constrained estimation. The issue of specification bears on the testing of migration theories, and assessing the role migration plays in job and housing markets: the direction and significance of the effects of economic variates on migration depends on the specification of the statistical model. The application is in the context of migration in London and South East England in the 1970s and 1980s." excerpt

  3. Chromosomal break points in irradiated and ethyl methane sulphonate treated leucocytes of patients with Down syndrome

    International Nuclear Information System (INIS)

    Reeja, T.C.; Chandra, N.; Marimuthu, K.M.

    1993-01-01

    Frequencies of chromosomal damage in the peripheral leucocytes of patients with Down syndrome, on exposure to gamma rays (2Gy) or ethyl methane sulphonate (EMS, 1 x 10 -4 M), were assessed. Analysis of break points in the chromosomes of irradiated cells revealed a non-random occurrence. Six of the break points observed in EMS-treated cells were found to overlap with those recorded in irradiated cells. Thirteen break points observed were found to correlate with the location of cancer-specific break points and four of these coincided with the bands where oncogenes have been located. Two break points were localised to the same bands as that of known heritable fragile sites. (author). 17 refs., 2 figs., 3 tabs

  4. Use of an autologous leucocyte and platelet-rich fibrin patch on hard-to-heal DFUs: a pilot study.

    Science.gov (United States)

    Löndahl, M; Tarnow, L; Karlsmark, T; Lundquist, R; Nielsen, A M; Michelsen, M; Nilsson, A; Zakrzewski, M; Jörgensen, B

    2015-04-01

    Leucopatch is a leukocyte and platelet-rich fibrin patch that provides concentrated blood cells and signal substances to the surface of an ulcer. It is produced by centrifugation of the patient's own venous blood. The aim of this pilot multicentre cohort study was to evaluate effects of the leucocyte patch in patients with hard-to-heal diabetic foot ulcers (DFUs). Non-ischaemic Wagner grade 1 or 2 DFUs with a duration of more than 6 weeks and a maximal area of 10cm² were included. Patients with >40% ulcer area change during a two-week run-in period were excluded. The treatment was applied once a week for up to 19 treatments or until the foot ulcer was completely epithelialised. The primary endpoint was healing within 20 weeks. Of the 60 patients who gave consent 16 were excluded during run-in period, 44 patients initiated study treatment and 39 were included in the per-protocol analysis. Complete epithelisation was achieved in 34% (per-protocol analysis 36%) at 12 weeks and 52% (59%) at 20 weeks. In patients with ulcer duration less than 6 months, 73% of ulcers healed within 20 weeks. Patients with healed ulcers had larger ulcer area reduction during the first two treatment weeks compared to non-healers. Adverse events were mild and rare. The leucocyte patch is well-tolerated, easy to use and has potential in the armamentarium of the DFU treatment, provided this outcome is confirmed in an appropriately powered randomised clinical trial.

  5. Compulsory Schooling Laws and Migration Across European Countries.

    Science.gov (United States)

    Aparicio Fenoll, Ainhoa; Kuehn, Zoë

    2017-12-01

    Educational attainment is a key factor for understanding why some individuals migrate and others do not. Compulsory schooling laws, which determine an individual's minimum level of education, can potentially affect migration. We test whether and how increasing the length of compulsory schooling influences migration of affected cohorts across European countries, a context where labor mobility is essentially free. We construct a novel database that includes information for 31 European countries on compulsory education reforms passed between 1950 and 1990. Combining this data with information on recent migration flows by cohorts, we find that an additional year of compulsory education reduces the number of individuals from affected cohorts who migrate in a given year by 9 %. Our results rely on the exogeneity of compulsory schooling laws. A variety of empirical tests indicate that European legislators did not pass compulsory education reforms as a reaction to changes in emigration rates or educational attainment.

  6. Migration within China and from China to the USA: the effects of migration networks, selectivity, and the rural political economy in Fujian Province.

    Science.gov (United States)

    Liang, Zai; Chunyu, Miao David

    2013-07-01

    This paper tests a new strategy for simultaneously studying internal migration within, and international migration from, China. Our theoretical discussion draws on ideas from migration-networks theory and studies of the transition to a market-oriented economy. Data collection is modelled on the Mexican Migration Project. We find that education is more important in initiating internal migration than international migration. Second, although the role of migration networks at a community level seems similar to that for Mexico-USA migration, the networks at a family level show a different pattern. Third, there is evidence that internal and international migration are competing options. Finally, we find that individuals with cadres (public officials) in the family are less likely to undertake internal migration, but more likely to participate in international migration, a finding that highlights the continuing significance of the cadres in coastal rural China.

  7. Certified reference materials for food packaging specific migration tests: development, validation and modelling

    NARCIS (Netherlands)

    Stoffers, N.H.

    2005-01-01

    Keywords:certified reference materials; diffusion; food contact materials; food packaging; laurolactam; migration modelling; nylon; specific migration This thesis compiles several research topics

  8. 99mTc-HMPAO labeled leucocyte, 99mTc-labeled antigranulocyte antibody and 67Ga scintigraphy in the evaluation of painful hip and knee prosthetic replacements

    International Nuclear Information System (INIS)

    Oliveira, S.; Pereira, L.; Joao, F.; Lima, J.

    2003-01-01

    Full text: Objective: To evaluate the utility of 99mTc-HMPAO labeled leucocyte, 99mTc-labeled anti-granulocyte antibody and 67Ga scintigraphy in patients suspected to have infected hip and knee replacements, from March/1998 to March/ 2002. Methods: Retrospective study of 33 patients (12 male, 21 female) with an average age of 61,1 ± 7,3 years. Nineteen had hip replacements and 14 were submitted to knee replacements. 99mTc-HMPAO labeled leucocyte scintigraphy was performed in 17 patients, 99mTc-labeled anti-granulocyte antibody scintigraphy in 13 patients and 67Ga scintigraphy in 3 patients. Twenty-six patients were also submitted to 3-phase 99mTc-MDP bone scintigraphy. Results were compared to those from studies with infection/inflammation agents. Concordant positive studies were considered to be a positive result for infection. A second study using 67Ga was also performed in 3 patients. Results: Diagnosis was based on surgical findings in 14 patients, pathologic study of biopsy specimen in 1 case and clinical/ imaging follow-up in 18 patients. Infection was detected in 22 cases and absent in 11. The conjoined evaluation of scintigraphic studies considered infection to be present in 20 cases and absent in 13. With infection/inflammation agents, 20 cases were positive (+) and 13 cases were negative (-). Using 99mTc-HMPAO labeled leucocytes, 12 cases were (+) and 5 cases were (-). With 99mTc-labeled anti-granulocyte antibodies, 8 cases were (+) and 5 were (-). With 67Ga, all 3 cases were (-). In patients with (+) studies using infection/ inflammation agents, a false positive case with 99mTc-HMPAO labeled leucocytes was reported. Two false negative cases were detected, both with 99mTc-labeled antigranulocyte antibodies, in patients with (-) studies. Regarding the studies with 99mTc-MDP, 24 were (+) and 2 were (-). Eighteen of these (+) cases were also (+) in studies with infection/inflammation agents, but 6 were (-) with these agents. Negative cases were also (-) in

  9. Plane-wave Least-squares Reverse Time Migration

    KAUST Repository

    Dai, Wei

    2012-11-04

    Least-squares reverse time migration is formulated with a new parameterization, where the migration image of each shot is updated separately and a prestack image is produced with common image gathers. The advantage is that it can offer stable convergence for least-squares migration even when the migration velocity is not completely accurate. To significantly reduce computation cost, linear phase shift encoding is applied to hundreds of shot gathers to produce dozens of planes waves. A regularization term which penalizes the image difference between nearby angles are used to keep the prestack image consistent through all the angles. Numerical tests on a marine dataset is performed to illustrate the advantages of least-squares reverse time migration in the plane-wave domain. Through iterations of least-squares migration, the migration artifacts are reduced and the image resolution is improved. Empirical results suggest that the LSRTM in plane wave domain is an efficient method to improve the image quality and produce common image gathers.

  10. Anti-inflammatory lipocortin 1 production by peripheral blood leucocytes in response to hydrocortisone.

    Science.gov (United States)

    Goulding, N J; Godolphin, J L; Sharland, P R; Peers, S H; Sampson, M; Maddison, P J; Flower, R J

    1990-06-16

    The presence and amount of the anti-inflammatory protein lipocortin 1 was determined in plasma and peripheral blood leucocytes by a highly specific, enzyme-linked immunosorbent assay. Within 120 min of a single intravenous dose of 100 mg hydrocortisone, the intracellular concentrations of lipocortin 1 in peripheral monocytes in 7 of 8 healthy men increased by a median of 225% (range 129-507%) compared with pretreatment levels, and mononuclear cell-surface lipocortin increased by a median of 224% (range 76-483%). Placebo injections had no effect. There was no increase at any time in free plasma or polymorph-associated lipocortin. In 3 of 4 subjects, induction of lipocortin was also observed when whole unseparated blood was incubated in vitro after steroid administration, but cells which had first been isolated and purified were refractory to such induction. Thus rapid changes in the concentration of an active anti-inflammatory protein can occur in man after normal therapeutic doses of hydrocortisone.

  11. Analysis of melamine migration from melamine food contact articles.

    Science.gov (United States)

    Chik, Z; Haron, D E Mohamad; Ahmad, E D; Taha, H; Mustafa, A M

    2011-01-01

    Migration of melamine has been determined for 41 types of retail melamine-ware products in Malaysia. This study was initiated by the Ministry of Health, Malaysia, in the midst of public anxiety on the possibility of melamine leaching into foods that come into contact with the melamine-ware. Thus, the objective of this study was to investigate the level of melamine migration in melamine utensils available on the market. Samples of melamine tableware, including cups and plates, forks and spoons, tumblers, bowls, etc., were collected from various retail outlets. Following the test guidelines for melamine migration set by the European Committee for Standardisation (CEN 2004) with some modifications, the samples were exposed to two types of food simulants (3% acetic acid and distilled water) at three test conditions (25°C (room temperature), 70 and 100°C) for 30 min. Melamine analysis was carried out using LC-MS/MS with a HILIC column and mobile phase consisting of ammonium acetate/formic acid (0.05%) in water and ammonium acetate/formic acid (0.05%) in acetonitrile (95 : 5, v/v). The limit of quantification (LOQ) was 5 ng/ml. Melamine migration was detected from all samples. For the articles tested with distilled water, melamine migration were [median (interquartile range)] 22.2 (32.6), 49.3 (50.9), 84.9 (89.9) ng/ml at room temperature (25°C), 70 and 100°C, respectively. In 3% acetic acid, melamine migration was 31.5 (35.7), 81.5 (76.2), 122.0 (126.7) ng/ml at room temperature (25°C), 70 and 100°C, respectively. This study suggests that excessive heat and acidity may directly affect melamine migration from melamine-ware products. However the results showed that melamine migration in the tested items were well below the specific migration limit (SML) of 30 mg/kg (30,000 ng/ml) set out in European Commission Directive 2002/72/EC.

  12. Migration of fluorochemical paper additives from food-contact paper into foods and food simulants.

    Science.gov (United States)

    Begley, T H; Hsu, W; Noonan, G; Diachenko, G

    2008-03-01

    Fluorochemical-treated paper was tested to determine the amount of migration that occurs into foods and food-simulating liquids and the characteristics of the migration. Migration characteristics of fluorochemicals from paper were examined in Miglyol, butter, water, vinegar, water-ethanol solutions, emulsions and pure oil containing small amounts of emulsifiers. Additionally, microwave popcorn and chocolate spread were used to investigate migration. Results indicate that fluorochemicals paper additives do migrate to food during actual package use. For example, we found that microwave popcorn contained 3.2 fluorochemical mg kg(-1) popcorn after popping and butter contained 0.1 mg kg(-1) after 40 days at 4 degrees C. Tests also indicate that common food-simulating liquids for migration testing and package material evaluation might not provide an accurate indication of the amount of fluorochemical that actually migrates to food. Tests show that oil containing small amounts of an emulsifier can significantly enhance migration of a fluorochemical from paper.

  13. DISCERNING EXOPLANET MIGRATION MODELS USING SPIN-ORBIT MEASUREMENTS

    International Nuclear Information System (INIS)

    Morton, Timothy D.; Johnson, John Asher

    2011-01-01

    We investigate the current sample of exoplanet spin-orbit measurements to determine whether a dominant planet migration channel can be identified, and at what confidence. We use the predictions of Kozai migration plus tidal friction and planet-planet scattering as our misalignment models, and we allow for a fraction of intrinsically aligned systems, explainable by disk migration. Bayesian model comparison demonstrates that the current sample of 32 spin-orbit measurements strongly favors a two-mode migration scenario combining planet-planet scattering and disk migration over a single-mode Kozai migration scenario. Our analysis indicates that between 34% and 76% of close-in planets (95% confidence) migrated via planet-planet scattering. Separately analyzing the subsample of 12 stars with T eff >6250 K-which Winn et al. predict to be the only type of stars to maintain their primordial misalignments-we find that the data favor a single-mode scattering model over Kozai with 85% confidence. We also assess the number of additional hot star spin-orbit measurements that will likely be necessary to provide a more confident model selection, finding that an additional 20-30 measurement has a >50% chance of resulting in a 95% confident model selection, if the current model selection is correct. While we test only the predictions of particular Kozai and scattering migration models in this work, our methods may be used to test the predictions of any other spin-orbit misaligning mechanism.

  14. Domestic and International Climate Migration from Rural Mexico

    Science.gov (United States)

    Nawrotzki, Raphael J.; Runfola, Daniel M.; Hunter, Lori M.; Riosmena, Fernando

    2016-01-01

    Evidence is increasing that climate change and variability may influence human migration patterns. However, there is less agreement regarding the type of migration streams most strongly impacted. This study tests whether climate change more strongly impacted international compared to domestic migration from rural Mexico during 1986-99. We employ eight temperature and precipitation-based climate change indices linked to detailed migration histories obtained from the Mexican Migration Project. Results from multilevel discrete-time event-history models challenge the assumption that climate-related migration will be predominantly short distance and domestic, but instead show that climate change more strongly impacted international moves from rural Mexico. The stronger climate impact on international migration may be explained by the self-insurance function of international migration, the presence of strong migrant networks, and climate-related changes in wage difference. While a warming in temperature increased international outmigration, higher levels of precipitation declined the odds of an international move. PMID:28439146

  15. Domestic and International Climate Migration from Rural Mexico.

    Science.gov (United States)

    Nawrotzki, Raphael J; Runfola, Daniel M; Hunter, Lori M; Riosmena, Fernando

    2016-12-01

    Evidence is increasing that climate change and variability may influence human migration patterns. However, there is less agreement regarding the type of migration streams most strongly impacted. This study tests whether climate change more strongly impacted international compared to domestic migration from rural Mexico during 1986-99. We employ eight temperature and precipitation-based climate change indices linked to detailed migration histories obtained from the Mexican Migration Project. Results from multilevel discrete-time event-history models challenge the assumption that climate-related migration will be predominantly short distance and domestic, but instead show that climate change more strongly impacted international moves from rural Mexico. The stronger climate impact on international migration may be explained by the self-insurance function of international migration, the presence of strong migrant networks, and climate-related changes in wage difference. While a warming in temperature increased international outmigration, higher levels of precipitation declined the odds of an international move.

  16. Volatile organic components migrating from plastic pipes (HDPE, PEX and PVC) into drinking water.

    Science.gov (United States)

    Skjevrak, Ingun; Due, Anne; Gjerstad, Karl Olav; Herikstad, Hallgeir

    2003-04-01

    High-density polyethylene pipes (HDPE), crossbonded polyethylene pipes (PEX) and polyvinyl chloride (PVC) pipes for drinking water were tested with respect to migration of volatile organic components (VOC) to water. The odour of water in contact with plastic pipes was assessed according to the quantitative threshold odour number (TON) concept. A major migrating component from HDPE pipes was 2,4-di-tert-butyl-phenol (2,4-DTBP) which is a known degradation product from antioxidants such as Irgafos 168(R). In addition, a range of esters, aldehydes, ketones, aromatic hydrocarbons and terpenoids were identified as migration products from HDPE pipes. Water in contact with HDPE pipes was assessed with respect to TON, and values > or =4 were determined for five out of seven brands of HDPE pipes. The total amount of VOC released to water during three successive test periods were fairly constant for the HDPE pipes. Corresponding migration tests carried out for PEX pipes showed that VOC migrated in significant amounts into the test water, and TON >/=5 of the test water were observed in all tests. Several of the migrated VOC were not identified. Oxygenates predominated the identified VOC in the test water from PEX pipes. Migration tests of PVC pipes revealed few volatile migrants in the test samples and no significant odour of the test water.

  17. Mini-review: Can non-human leucocyte antigen genes determine susceptibility to severe dengue syndromes?

    Science.gov (United States)

    Ng, Dorothy; Ghosh, Aparna; Jit, Mark; Seneviratne, Suranjith L

    2017-09-01

    Dengue viral infections are endemic or epidemic in virtually all tropical countries. Among individuals infected with the dengue virus, severe dengue syndromes (i.e., dengue haemorrhagic fever and dengue shock syndromes) tend to affect only some and this may be due to a combination of host genetic susceptibility and viral factors. In this review article we analyse and discuss the present knowledge of non-human leucocyte antigen host genetic susceptibility to severe dengue syndromes. The relevance of genetic polymorphisms in the pathways of antigen recognition, uptake, processing and presentation, activation of interferon α responses, mast cell and complement activation and T cell activation and dengue disease severity has been reviewed and analysed. © The Author(s) 2018. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Evaluation of Ion Torrent sequencing technology for rapid clinical human leucocyte antigen typing.

    Science.gov (United States)

    Guerra, Sandra G; Chong, Winnie; Brown, Colin J; Navarrete, Cristina V

    2018-06-05

    The development of techniques to define the human leucocyte antigen (HLA) region has proven to be challenging due to its high level of polymorphism. Within a clinical laboratory, a technique for high-resolution HLA typing, which is rapid and cost effective is essential. NGS has provided a rapid, high-resolution HLA typing solution, which has reduced the number of HLA ambiguities seen with other typing methods. In this study, the One Lambda NXType NGS kit was tested on the Ion Torrent PGM platform. A total of 362 registry donors from four ethnic populations (Europeans, South Asians, Africans and Chinese) were NGS HLA typed across 9-loci (HLA-A, -B, -C, -DRB1,-DRB345 -DQB1 and -DPB1). Concordance rates of 91%-98% were obtained (for HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1) when compared to historical PCR-SSO HLA types, and the identification of uncommon alleles such as A*24:07:01 and C*04:82 were observed. A turnaround time of four days was achieved for typing 44 samples. However, some limitations were observed; primer locations did not allow all ambiguities to be resolved for HLA Class II where Exon I and IV amplification are needed (HLA-DRB1*04:07:01/04:92, HLA-DRB1*09:01:02/*09:21 and HLA-DRB1*12:01:01/*12:10). This study has demonstrated high-resolution typing by NGS can be achieved in an acceptable turnaround time for a clinical laboratory; however, the Ion Torrent workflow has some technical limitations that should be addressed. © 2018 John Wiley & Sons Ltd.

  19. Genetic determinants of leucocyte telomere length in children: a neglected and challenging field.

    Science.gov (United States)

    Stathopoulou, Maria G; Petrelis, Alexandros M; Buxton, Jessica L; Froguel, Philippe; Blakemore, Alexandra I F; Visvikis-Siest, Sophie

    2015-03-01

    Telomere length is associated with a large range of human diseases. Genome-wide association studies (GWAS) have identified genetic variants that are associated with leucocyte telomere length (LTL). However, these studies are limited to adult populations. Nevertheless, childhood is a crucial period for the determination of LTL, and the assessment of age-specific genetic determinants, although neglected, could be of great importance. Our aim was to provide insights and preliminary results on genetic determinants of LTL in children. Healthy children (n = 322, age range = 6.75-17 years) with available GWAS data (Illumina Human CNV370-Duo array) were included. The LTL was measured using multiplex quantitative real-time polymerase chain reaction. Linear regression models adjusted for age, gender, parental age at child's birth, and body mass index were used to test the associations of LTL with polymorphisms identified in adult GWAS and to perform a discovery-only GWAS. The previously GWAS-identified variants in adults were not associated with LTL in our paediatric sample. This lack of association was not due to possible interactions with age or gene × gene interactions. Furthermore, a discovery-only GWAS approach demonstrated six novel variants that reached the level of suggestive association (P ≤ 5 × 10(-5)) and explain a high percentage of children's LTL. The study of genetic determinants of LTL in children may identify novel variants not previously identified in adults. Studies in large-scale children populations are needed for the confirmation of these results, possibly through a childhood consortium that could better handle the methodological challenges of LTL genetic epidemiology field. © 2015 John Wiley & Sons Ltd.

  20. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai

    2017-03-08

    We use elastic least-squares reverse time migration (LSRTM) to invert for the reflectivity images of P- and S-wave impedances. Elastic LSRTMsolves the linearized elastic-wave equations for forward modeling and the adjoint equations for backpropagating the residual wavefield at each iteration. Numerical tests on synthetic data and field data reveal the advantages of elastic LSRTM over elastic reverse time migration (RTM) and acoustic LSRTM. For our examples, the elastic LSRTM images have better resolution and amplitude balancing, fewer artifacts, and less crosstalk compared with the elastic RTM images. The images are also better focused and have better reflector continuity for steeply dipping events compared to the acoustic LSRTM images. Similar to conventional leastsquares migration, elastic LSRTM also requires an accurate estimation of the P- and S-wave migration velocity models. However, the problem remains that, when there are moderate errors in the velocity model and strong multiples, LSRTMwill produce migration noise stronger than that seen in the RTM images.

  1. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai; Schuster, Gerard T.

    2017-01-01

    We use elastic least-squares reverse time migration (LSRTM) to invert for the reflectivity images of P- and S-wave impedances. Elastic LSRTMsolves the linearized elastic-wave equations for forward modeling and the adjoint equations for backpropagating the residual wavefield at each iteration. Numerical tests on synthetic data and field data reveal the advantages of elastic LSRTM over elastic reverse time migration (RTM) and acoustic LSRTM. For our examples, the elastic LSRTM images have better resolution and amplitude balancing, fewer artifacts, and less crosstalk compared with the elastic RTM images. The images are also better focused and have better reflector continuity for steeply dipping events compared to the acoustic LSRTM images. Similar to conventional leastsquares migration, elastic LSRTM also requires an accurate estimation of the P- and S-wave migration velocity models. However, the problem remains that, when there are moderate errors in the velocity model and strong multiples, LSRTMwill produce migration noise stronger than that seen in the RTM images.

  2. De‐blending reverse‐time migration

    KAUST Repository

    Fei, Tong W.; Luo, Yi; Schuster, Gerard T.

    2010-01-01

    Reverse‐time migration (RTM), based on the full two‐way wave equation, has gained interest and become a popular imaging tool for complex structures in the last few years. The method is well‐known for its ability to better image the steeply dipping and overturned structures than the migration methods based on the one‐way wave equation extrapolation. However, the RTM image often contains low frequency and back‐scattering noise, and the imaging quality is sensitive to the migration velocity. In order to improve the RTM imaging quality and make the RTM image less sensitive to the velocity model, we developed an RTM de‐blending technique which separates upgoing and downgoing source and receiver wavefields, and then use them to construct final RTM images. Test results show that decomposed images obtained from only the downgoing source and receiver wavefields are less sensitive to velocity. It removes unwanted noise and migration artifacts from conventional RTM, and the imaging quality is greatly improved compared with a conventional RTM image.

  3. De‐blending reverse‐time migration

    KAUST Repository

    Fei, Tong W.

    2010-10-17

    Reverse‐time migration (RTM), based on the full two‐way wave equation, has gained interest and become a popular imaging tool for complex structures in the last few years. The method is well‐known for its ability to better image the steeply dipping and overturned structures than the migration methods based on the one‐way wave equation extrapolation. However, the RTM image often contains low frequency and back‐scattering noise, and the imaging quality is sensitive to the migration velocity. In order to improve the RTM imaging quality and make the RTM image less sensitive to the velocity model, we developed an RTM de‐blending technique which separates upgoing and downgoing source and receiver wavefields, and then use them to construct final RTM images. Test results show that decomposed images obtained from only the downgoing source and receiver wavefields are less sensitive to velocity. It removes unwanted noise and migration artifacts from conventional RTM, and the imaging quality is greatly improved compared with a conventional RTM image.

  4. Pulmonary deposition and disappearance of aerosolised secretory leucocyte protease inhibitor.

    Science.gov (United States)

    Stolk, J.; Camps, J.; Feitsma, H. I.; Hermans, J.; Dijkman, J. H.; Pauwels, E. K.

    1995-01-01

    BACKGROUND--The neutrophil elastase inhibitor, secretory leucocyte protease inhibitor (SLPI), is a potential therapeutic tool in inflammatory lung diseases such as cystic fibrosis and pulmonary emphysema. The distribution and disappearance in the lung of aerosolised recombinant SLPI (rSLPI) was investigated in healthy humans and in patients with cystic fibrosis or alpha 1-antitrypsin-associated emphysema. METHODS--To distinguish aerosolised rSLPI from endogenous SLPI the recombinant inhibitor was radiolabelled with 99m-technetium (99mTc) pertechnetate. Distribution and disappearance of aerosolised 99mTc-rSLPI in the lungs were studied by gamma radiation imaging. RESULTS--The deposition of 99mTc-rSLPI in normal volunteers was homogeneous in all lung lobes, while in patients with cystic fibrosis or emphysema only well ventilated areas showed deposition of the aerosol. The disappearance rate of 99mTc-rSLPI was biexponential. The half life of the rapid phase was 0.2-2.8 hours, while that of the slow phase was more than 24 hours. CONCLUSIONS--Future aerosol therapy with rSLPI will be most beneficial for well ventilated lung tissue that needs protection against neutrophil derived elastase. It may be more difficult to neutralise the burden of elastase in poorly ventilated, highly inflamed areas as are seen in cystic fibrosis. Images PMID:7638807

  5. Protective human leucocyte antigen haplotype, HLA-DRB1*01-B*14, against chronic Chagas disease in Bolivia.

    Directory of Open Access Journals (Sweden)

    Florencia del Puerto

    Full Text Available BACKGROUND: Chagas disease, caused by the flagellate parasite Trypanosoma cruzi affects 8-10 million people in Latin America. The mechanisms that underlie the development of complications of chronic Chagas disease, characterized primarily by pathology of the heart and digestive system, are not currently understood. To identify possible host genetic factors that may influence the clinical course of Chagas disease, Human Leucocyte Antigen (HLA regional gene polymorphism was analyzed in patients presenting with differing clinical symptoms. METHODOLOGY: Two hundred and twenty nine chronic Chagas disease patients in Santa Cruz, Bolivia, were examined by serological tests, electrocardiogram (ECG, and Barium enema colon X-ray. 31.4% of the examinees showed ECG alterations, 15.7% megacolon and 58.1% showed neither of them. A further 62 seropositive megacolon patients who had undergone colonectomy due to acute abdomen were recruited. We analyzed their HLA genetic polymorphisms (HLA-A, HLA-B, MICA, MICB, DRB1 and TNF-alpha promoter region mainly through Sequence based and LABType SSO typing test using LUMINEX Technology. PRINCIPAL FINDINGS: The frequencies of HLA-DRB1*01 and HLA-B*14:02 were significantly lower in patients suffering from megacolon as well as in those with ECG alteration and/or megacolon compared with a group of patients with indeterminate symptoms. The DRB1*0102, B*1402 and MICA*011 alleles were in strong Linkage Disequilibrium (LD, and the HLA-DRB1*01-B*14-MICA*011 haplotype was associated with resistance against chronic Chagas disease. CONCLUSIONS: This is the first report of HLA haplotype association with resistance to chronic Chagas disease.

  6. EARLY IDENTIFICATION OF SWINE INFLUENZA A (H1N1- BASING ONEPIDEMIOLOGIC CLUE, CLINICAL PRESENTATION, IMAGING FINDINGS, PERIPHERAL LEUCOCYTE COUNTS AND SPO2 LEVELS

    Directory of Open Access Journals (Sweden)

    Venkateswararao Kopparti

    2017-11-01

    Full Text Available BACKGROUND The present study is a retrospective study of 22 cases of RT-PCR positive swine influenza spanning from 2014 to 20-09-2017 with main objective of early identification of influenza A H1N1 basing on epidemiological clue, clinical presentation, imaging findings and lab parameters as early antiviral therapy and judicious management of ARDS brings good outcome as per available literature. 1,2,3 MATERIAL AND METHODS 22 confirmed adult cases of swine influenza by throat/nasopharyngeal swab RT-PCR for H1N1 were studied in terms of clinical presentation, imaging findings, lab manifestations and SpO2 levels4 with particular emphasis on imaging findings. RESULTS 95% presented with symptoms of Influenza-Like Illness (ILI. Nearly, 80% of patients belonged to fourth to fifth decades. Leucocyte count was normal in 75% and 25% had low leucocyte count (<4000, SpO2 levels were normal in 25% and low in 75% cases. CXR was abnormal in 82% of cases of which 83% had mid/lower zone peripheral, patchy, pleural-based consolidations and 17% showed all lung zone opacities. HRCT chest done in 32% of cases showed similar features of chest xray findings with dominant mid/lower zone pleural-based consolidations to ground-glass haziness without pleural effusions and no mediastinal nodal involvement. CONCLUSION As intermittent outbreaks of swine influenza are still continuing in India with recent spurt in incidence in the months of April/May 2017, early diagnosis of H1N1 A is necessary for improved outcome. Early diagnosis is feasible by ILI presentation, normal or low leucocyte count, low SpO2 levels and characteristic radiologic findings of bilateral mid/lower zone pleural-based peripheral patchy opacities to consolidations. As this can be done at peripheral level, primary care physicians need to be sensitised in early diagnosis and treatment and prompt referral to higher centres when needed. Since, the present study is a retrospective one and of public health

  7. Dispersal and migration

    Directory of Open Access Journals (Sweden)

    Schwarz, C.

    2004-06-01

    overlay maps of effort to try and remove any induced artefacts in the data. Differences in timing or the route of migration has often been studies separately. Lokki and Saurola (Lokki & Saurola, 2004 develop an omnibus procedure to test if the migration timing and/or route differ among two populations of birds (e.g. males vs females. It uses a randomization test to calibrate the test statistic. However, it makes the key assumptions about equal recovery effort in time and space so that the method may be most applicable to comparison among species with similar migration timing and movement to keep differential sighting/recovery rates from affecting the result. Of course, it is in these cases where it is most difficulty to separate the groups which will require substantial samples to have good performance. Thorup and Rahbek (Thorup & Rahbek, 2004 provide a framework for accounting for unequal spatial recovery probability investigating the geometric influence of ocean and sea on observed migratory patterns. Taking the data set of Pied Flycatchers (Ficedula hypoleuca ringed as nestlings in Scandinavia and recovered en route on their initial migration and using a model based on the clock–and–compass innate navigation hypothesis they are showing that geometric constraints explain quite a bit of the variation in ring–recoveries. The model also shows that ring recovery patterns do reflect the migratory patterns, and that they are suitable for an analysis of the concentration of the migratory route which is important for the general use of ringing data in studies of migration. This is important for the general use of ringing data in studies of migration and dispersal. The new approach has also implications for understanding the migratory orientation program. The compiled papers highlight some novel ideas of how to analyse band recoveries to investigate migration routes and migration behaviour as well as dispersal patterns among birds and dolphins. Multistate modeling appears

  8. A Chaos Theory Perspective on International Migration

    Directory of Open Access Journals (Sweden)

    Anca Tănasie

    2017-12-01

    Full Text Available This paper aims at providing a different approach to international migration analysis, beyond classical models previously proposed by specialized literature. Chaos theory is getting more and more applied into macroeconomics once traditional linear models or even previous dynamic analysis become less suitable. Modern science sees chaos as unpredictable evolution, maybe even disorder. Still, chaos has got its own rules and can describe many dynamic phenomena within our world. Thus, we test whether international migration data falls under the rules of chaos and whether recent developments within the “European migration crisis” (the total daily migration inflows towards the coasts of Italy, by sea, from January 2014 to April 2017 could be described as chaotic.

  9. Use of an autologous leucocyte and platelet-rich fibrin patch on hard-to-heal DFUs

    DEFF Research Database (Denmark)

    Löndahl, M; Tarnow, L.; Karlsmark, T

    2015-01-01

    OBJECTIVE: Leucopatch is a leukocyte and platelet-rich fibrin patch that provides concentrated blood cells and signal substances to the surface of an ulcer. It is produced by centrifugation of the patient's own venous blood. The aim of this pilot multicentre cohort study was to evaluate effects...... was applied once a week for up to 19 treatments or until the foot ulcer was completely epithelialised. The primary endpoint was healing within 20 weeks. RESULTS: Of the 60 patients who gave consent 16 were excluded during run-in period, 44 patients initiated study treatment and 39 were included in the per...... compared to non-healers. Adverse events were mild and rare. CONCLUSION: The leucocyte patch is well-tolerated, easy to use and has potential in the armamentarium of the DFU treatment, provided this outcome is confirmed in an appropriately powered randomised clinical trial....

  10. Hydrology/Radionuclide Migration Program and related research activities

    International Nuclear Information System (INIS)

    Jones, M.A.

    1992-02-01

    This report presents the results of technical studies conducted under the Hydrology/Radionuclide Migration Program (HRMP) at the Nevada Test Site (NTS) for the period of October 1, 1985 through September 30, 1986. The HRMP was initiated in 1973 as the Radionuclide Migration Program to study and better understand the hydrologic systems of the NTS and potential movement and rates of movement of radionuclides and other contaminants injected into these systems by underground nuclear testing

  11. How neurons migrate: a dynamic in-silico model of neuronal migration in the developing cortex

    LENUS (Irish Health Repository)

    Setty, Yaki

    2011-09-30

    Abstract Background Neuronal migration, the process by which neurons migrate from their place of origin to their final position in the brain, is a central process for normal brain development and function. Advances in experimental techniques have revealed much about many of the molecular components involved in this process. Notwithstanding these advances, how the molecular machinery works together to govern the migration process has yet to be fully understood. Here we present a computational model of neuronal migration, in which four key molecular entities, Lis1, DCX, Reelin and GABA, form a molecular program that mediates the migration process. Results The model simulated the dynamic migration process, consistent with in-vivo observations of morphological, cellular and population-level phenomena. Specifically, the model reproduced migration phases, cellular dynamics and population distributions that concur with experimental observations in normal neuronal development. We tested the model under reduced activity of Lis1 and DCX and found an aberrant development similar to observations in Lis1 and DCX silencing expression experiments. Analysis of the model gave rise to unforeseen insights that could guide future experimental study. Specifically: (1) the model revealed the possibility that under conditions of Lis1 reduced expression, neurons experience an oscillatory neuron-glial association prior to the multipolar stage; and (2) we hypothesized that observed morphology variations in rats and mice may be explained by a single difference in the way that Lis1 and DCX stimulate bipolar motility. From this we make the following predictions: (1) under reduced Lis1 and enhanced DCX expression, we predict a reduced bipolar migration in rats, and (2) under enhanced DCX expression in mice we predict a normal or a higher bipolar migration. Conclusions We present here a system-wide computational model of neuronal migration that integrates theory and data within a precise

  12. How neurons migrate: a dynamic in-silico model of neuronal migration in the developing cortex

    Directory of Open Access Journals (Sweden)

    Skoblov Nikita

    2011-09-01

    Full Text Available Abstract Background Neuronal migration, the process by which neurons migrate from their place of origin to their final position in the brain, is a central process for normal brain development and function. Advances in experimental techniques have revealed much about many of the molecular components involved in this process. Notwithstanding these advances, how the molecular machinery works together to govern the migration process has yet to be fully understood. Here we present a computational model of neuronal migration, in which four key molecular entities, Lis1, DCX, Reelin and GABA, form a molecular program that mediates the migration process. Results The model simulated the dynamic migration process, consistent with in-vivo observations of morphological, cellular and population-level phenomena. Specifically, the model reproduced migration phases, cellular dynamics and population distributions that concur with experimental observations in normal neuronal development. We tested the model under reduced activity of Lis1 and DCX and found an aberrant development similar to observations in Lis1 and DCX silencing expression experiments. Analysis of the model gave rise to unforeseen insights that could guide future experimental study. Specifically: (1 the model revealed the possibility that under conditions of Lis1 reduced expression, neurons experience an oscillatory neuron-glial association prior to the multipolar stage; and (2 we hypothesized that observed morphology variations in rats and mice may be explained by a single difference in the way that Lis1 and DCX stimulate bipolar motility. From this we make the following predictions: (1 under reduced Lis1 and enhanced DCX expression, we predict a reduced bipolar migration in rats, and (2 under enhanced DCX expression in mice we predict a normal or a higher bipolar migration. Conclusions We present here a system-wide computational model of neuronal migration that integrates theory and data within a

  13. Depth migration and de-migration for 3-D migration velocity analysis; Migration profondeur et demigration pour l'analyse de vitesse de migration 3D

    Energy Technology Data Exchange (ETDEWEB)

    Assouline, F.

    2001-07-01

    3-D seismic imaging of complex geologic structures requires the use of pre-stack imaging techniques, the post-stack ones being unsuitable in that case. Indeed, pre-stack depth migration is a technique which allows to image accurately complex structures provided that we have at our disposal a subsurface velocity model accurate enough. The determination of this velocity model is thus a key element for seismic imaging, and to this end, migration velocity analysis methods have met considerable interest. The SMART method is a specific migration velocity analysis method: the singularity of this method is that it does not rely on any restrictive assumptions on the complexity of the velocity model to determine. The SMART method uses a detour through the pre-stack depth migrated domain for extracting multi-offset kinematic information hardly accessible in the time domain. Once achieved the interpretation of the pre-stack depth migrated seismic data, a kinematic de-migration technique of the interpreted events enables to obtain a consistent kinematic database (i.e. reflection travel-times). Then, the inversion of these travel-times, by means of reflection tomography, allows the determination of an accurate velocity model. To be able to really image geologic structures for which the 3-D feature is predominant, we have studied the implementation of migration velocity analysis in 3-D in the context of the SMART method, and more generally, we have developed techniques allowing to overcome the intrinsic difficulties in the 3-D aspects of seismic imaging. Indeed, although formally the SMART method can be directly applied to the case of 3-D complex structures, the feasibility of its implementation requires to choose well the imaging domain. Once this choice done, it is also necessary to conceive a method allowing, via the associated de-migration, to obtain the reflection travel-times. We first consider the offset domain which constitutes, still today, the strategy most usually used

  14. Multi-source least-squares reverse time migration

    KAUST Repository

    Dai, Wei

    2012-06-15

    Least-squares migration has been shown to improve image quality compared to the conventional migration method, but its computational cost is often too high to be practical. In this paper, we develop two numerical schemes to implement least-squares migration with the reverse time migration method and the blended source processing technique to increase computation efficiency. By iterative migration of supergathers, which consist in a sum of many phase-encoded shots, the image quality is enhanced and the crosstalk noise associated with the encoded shots is reduced. Numerical tests on 2D HESS VTI data show that the multisource least-squares reverse time migration (LSRTM) algorithm suppresses migration artefacts, balances the amplitudes, improves image resolution and reduces crosstalk noise associated with the blended shot gathers. For this example, the multisource LSRTM is about three times faster than the conventional RTM method. For the 3D example of the SEG/EAGE salt model, with a comparable computational cost, multisource LSRTM produces images with more accurate amplitudes, better spatial resolution and fewer migration artefacts compared to conventional RTM. The empirical results suggest that multisource LSRTM can produce more accurate reflectivity images than conventional RTM does with a similar or less computational cost. The caveat is that the LSRTM image is sensitive to large errors in the migration velocity model. © 2012 European Association of Geoscientists & Engineers.

  15. Multi-source least-squares reverse time migration

    KAUST Repository

    Dai, Wei; Fowler, Paul J.; Schuster, Gerard T.

    2012-01-01

    Least-squares migration has been shown to improve image quality compared to the conventional migration method, but its computational cost is often too high to be practical. In this paper, we develop two numerical schemes to implement least-squares migration with the reverse time migration method and the blended source processing technique to increase computation efficiency. By iterative migration of supergathers, which consist in a sum of many phase-encoded shots, the image quality is enhanced and the crosstalk noise associated with the encoded shots is reduced. Numerical tests on 2D HESS VTI data show that the multisource least-squares reverse time migration (LSRTM) algorithm suppresses migration artefacts, balances the amplitudes, improves image resolution and reduces crosstalk noise associated with the blended shot gathers. For this example, the multisource LSRTM is about three times faster than the conventional RTM method. For the 3D example of the SEG/EAGE salt model, with a comparable computational cost, multisource LSRTM produces images with more accurate amplitudes, better spatial resolution and fewer migration artefacts compared to conventional RTM. The empirical results suggest that multisource LSRTM can produce more accurate reflectivity images than conventional RTM does with a similar or less computational cost. The caveat is that the LSRTM image is sensitive to large errors in the migration velocity model. © 2012 European Association of Geoscientists & Engineers.

  16. Wave-equation Q tomography and least-squares migration

    KAUST Repository

    Dutta, Gaurav

    2016-03-01

    This thesis designs new methods for Q tomography and Q-compensated prestack depth migration when the recorded seismic data suffer from strong attenuation. A motivation of this work is that the presence of gas clouds or mud channels in overburden structures leads to the distortion of amplitudes and phases in seismic waves propagating inside the earth. If the attenuation parameter Q is very strong, i.e., Q<30, ignoring the anelastic effects in imaging can lead to dimming of migration amplitudes and loss of resolution. This, in turn, adversely affects the ability to accurately predict reservoir properties below such layers. To mitigate this problem, I first develop an anelastic least-squares reverse time migration (Q-LSRTM) technique. I reformulate the conventional acoustic least-squares migration problem as a viscoacoustic linearized inversion problem. Using linearized viscoacoustic modeling and adjoint operators during the least-squares iterations, I show with numerical tests that Q-LSRTM can compensate for the amplitude loss and produce images with better balanced amplitudes than conventional migration. To estimate the background Q model that can be used for any Q-compensating migration algorithm, I then develop a wave-equation based optimization method that inverts for the subsurface Q distribution by minimizing a skeletonized misfit function ε. Here, ε is the sum of the squared differences between the observed and the predicted peak/centroid-frequency shifts of the early-arrivals. Through numerical tests on synthetic and field data, I show that noticeable improvements in the migration image quality can be obtained from Q models inverted using wave-equation Q tomography. A key feature of skeletonized inversion is that it is much less likely to get stuck in a local minimum than a standard waveform inversion method. Finally, I develop a preconditioning technique for least-squares migration using a directional Gabor-based preconditioning approach for isotropic

  17. Semantics-Driven Migration of Java Programs: a Practical Experience

    Directory of Open Access Journals (Sweden)

    Artyom O. Aleksyuk

    2017-01-01

    Full Text Available The purpose of the study is to demonstrate the feasibility of automated code migration to a new set of programming libraries. Code migration is a common task in modern software projects. For example, it may arise when a project should be ported to a more secure or feature-rich library, a new platform or a new version of an already used library. The developed method and tool are based on the previously created by the authors a formalism for describing libraries semantics. The formalism specifies a library behaviour by using a system of extended finite state machines (EFSM. This paper outlines the metamodel designed to specify library descriptions and proposes an easy to use domainspecific language (DSL, which can be used to define models for particular libraries. The mentioned metamodel directly forms the code migration procedure. A process of migration is split into five steps, and each step is also described in the paper. The procedure uses an algorithm based on the breadth- first search extended for the needs of the migration task. Models and algorithms were implemented in the prototype of an automated code migration tool. The prototype was tested by both artificial code examples and a real-world open source project. The article describes the experiments performed, the difficulties that have arisen in the process of migration of test samples, and how they are solved in the proposed procedure. The results of experiments indicate that code migration can be successfully automated. 

  18. The gravity model of labor migration behavior

    Science.gov (United States)

    Alexandr, Tarasyev; Alexandr, Tarasyev

    2017-07-01

    In this article, we present a dynamic inter-regional model, that is based on the gravity approach to migration and describes in continuous time the labor force dynamics between a number of conjugate regions. Our modification of the gravity migration model allows to explain the migration processes and to display the impact of migration on the regional economic development both for regions of origin and attraction. The application of our model allows to trace the dependency between salaries levels, total workforce, the number of vacancies and the number unemployed people in simulated regions. Due to the gravity component in our model the accuracy of prediction for migration flows is limited by the distance range between analyzed regions, so this model is tested on a number of conjugate neighbor regions. Future studies will be aimed at development of a multi-level dynamic model, which allows to construct a forecast for unemployment and vacancies trends on the first modeling level and to use these identified parameters on the second level for describing dynamic trajectories of migration flows.

  19. Protective effect of gingerol on leucocyte and bone marrow DNA of 60Co γ-rays irradiated mice

    International Nuclear Information System (INIS)

    Xie Zhenfei; Zhou Yu; Geng Yanyan; Zeng Xianyin

    2012-01-01

    In this article, the effect of gingerol on peripheral leucocyte and bone marrow DNA of 60 Co γ-rays irradiated mice was developed., Twenty-four healthy healthy female Kunming mice were randomly divided into 4 groups: control, gingerol, irradiation and gingerol + irradiation group. Gingerol group and gingerol + irradiation group were given gingerol intragastrically once a day for five days. Irradiation group and gingerol + irradiation group were suffered from 5 Gy 60 Co γ-rays irradiation at the rate of 1.2 Gy/min on the 6 th day. Blood samples, spleens, livers and thigh bones were collected to be measured after 48 h. The results showed that, compared with irradiation group, gingerol + irradiation group had significantly higher spleen index (p 60 Co γ-rays irradiated mice. (authors)

  20. International Migration of Couples

    DEFF Research Database (Denmark)

    Junge, Martin; Munk, Martin D.; Nikolka, Till

    2018-01-01

    Migrant self-selection is important to labor markets and public finances in both origin and destination countries. We develop a theoretical model regarding the migration of dual-earner couples and test it using population-wide administrative data from Denmark. Our model predicts that the probabil...

  1. 3D Multi‐source Least‐squares Reverse Time Migration

    KAUST Repository

    Dai, Wei; Boonyasiriwat, Chaiwoot; Schuster, Gerard T.

    2010-01-01

    : random time shift, random source polarity and random source location selected from a pre‐designed table. Numerical tests for the 3D SEG/EAGE Overthrust model show that multi‐source LSRTM can suppress migration artifacts in the migration image and remove

  2. Effect of central nervous system radiotherapy in children with acute lymphoblastic leukaemia on lymphocyte subpopulations and indicators of leucocyte migration inhibition in the peripheral blood

    International Nuclear Information System (INIS)

    Cesarz-Kruz, E.; Lukas, A; Sroczynska, M.; Lukas, W; Sonta-Jakimczyk, D.

    1981-01-01

    The reported investigations of changes in lymphocyte subpopulations and indicators of leycocyte migration inhibition in the peripheral blood were carried out in 17 children with acute lymphoblastic leukaemia subjected to prophylactic irradiation of the central nervous system. It was found that the depressive effect of radioprophylaxis affected mostly lymphocytes B. The usefulness of immunomodulation application in children with this leukaemia immediately after completion of radiotherapy is considered. (author)

  3. Flexibility of continental navigation and migration in European mallards

    DEFF Research Database (Denmark)

    van Toor, Mariëlle L.; Hedenström, Anders; Waldenström, Jonas

    2013-01-01

    The ontogeny of continent-wide navigation mechanisms of the individual organism, despite being crucial for the understanding of animal movement and migration, is still poorly understood. Several previous studies, mainly conducted on passerines, indicate that inexperienced, juvenile birds may...... abilities. Here we tested whether immature mallard ducks correct for latitudinal displacement during fall migration within Europe. During two consecutive fall migration periods, we caught immature females on a stopover site in southeast Sweden, and translocated a group of them ca. 1,000 km to southern...... Germany. We followed the movements of the ducks via satellite GPS-tracking and observed their migration decisions during the fall and consecutive spring migration. The control animals released in Ottenby behaved as expected from banding recoveries: they continued migration during the winter and in spring...

  4. Information pertinent to the migration of radionuclides in ground water at the Nevada Test Site. Part 2: annotated bibliography

    International Nuclear Information System (INIS)

    Borg, I.Y.; Stone, R.; Levy, H.B.; Ramspott, L.D.

    1976-01-01

    Part 2 of UCRL-52078 consists of the bibliography and abstracts that were compiled in the course of searching the literature for information on the migration of radionuclides in groundwater at the Nevada Test Site. The bibliography also includes numerous references to work done at foreign nuclear centers or contracted to outside agencies by these same centers

  5. Migration of nanosized layered double hydroxide platelets from polylactide nanocomposite films.

    Science.gov (United States)

    Schmidt, B; Katiyar, V; Plackett, D; Larsen, E H; Gerds, N; Koch, C Bender; Petersen, J H

    2011-01-01

    Melt-extruded L-polylactide (PLA) nanocomposite films were prepared from commercially available PLA and laurate-modified Mg-Al layered double hydroxide (LDH-C12). Three films were tested for total migration as well as specific migration of LDH, tin, laurate and low molecular weight PLA oligomers (OLLA). This is the first reported investigation on the migration properties of PLA-LDH nanocomposite films. The tests were carried out as part of an overall assessment of the suitability of such films for use as food contact materials (FCM). Total migration was determined according to a European standard method. All three films showed migration of nanosized LDH, which was quantified using acid digestion followed by inductively coupled plasma mass spectrometric (ICP-MS) detection of (26)Mg. Migration of LDH from the films was also confirmed by examining migrates using transmission electron microscopy (TEM) and was attributed indirectly to the significant PLA molecular weight reduction observed in extruded PLA-LDH-C12 films. Migration of tin was detected in two of the film samples prepared by dispersion of LDH-C12 using a masterbatch technique and migration of the laurate organomodifier took place from all three film types. The results indicate that the material properties are in compliance with the migration limits for total migration and specific lauric acid migration as set down by the EU legislation for FCM, at least if a reduction factor for fresh meat is taken into consideration. The tin detected arises from the use of organotin catalysts in the manufacture of PLA.

  6. Individualisation of Migration from the East? Comparison of Different Socio-Demographic Groups and their Migration Intentions

    Directory of Open Access Journals (Sweden)

    Maarja Saar

    2016-12-01

    Full Text Available Recent studies on Eastern European migration argue that moving for self-development reasons is becoming increasingly common among this group. Furthermore, it is suggested that migration from the East is becoming individualised and less dependent on social surroundings. Nevertheless, most such results rely on interviews conducted among certain social groups, such as the young and highly skilled. Hence, the comparison between different social groups and their motivations is rarely provided and, therefore, the claims about increased individualisation might be premature. This article uses the Estonian Household Module Survey, including responses from 620 Estonians intending to migrate, to evaluate if migration flows are indeed becoming more individualised and less dependent on social surroundings. Using cluster analysis, three different groups — self-development, economic and life quality migrants — are formed, which are then tested using regression analysis to check for the influence of socio-demographic variables. The article concludes that socio-demographic variables such as gender, age, ethnicity, family status and socio-economic status are still relevant for migration intentions. Indeed, a new group of Eastern European migrants, mainly oriented towards self-development, is emerging; however, it is small and consists mostly of young, Estonian-speaking females. The results complicate the notions of free mobility and liquid migration from Eastern Europe and illustrate that there is a need to pay attention to the increasing group differences in these societies

  7. The possibilities of compressed sensing based migration

    KAUST Repository

    Aldawood, Ali

    2013-09-22

    Linearized waveform inversion or Least-square migration helps reduce migration artifacts caused by limited acquisition aperture, coarse sampling of sources and receivers, and low subsurface illumination. However, leastsquare migration, based on L2-norm minimization of the misfit function, tends to produce a smeared (smoothed) depiction of the true subsurface reflectivity. Assuming that the subsurface reflectivity distribution is a sparse signal, we use a compressed-sensing (Basis Pursuit) algorithm to retrieve this sparse distribution from a small number of linear measurements. We applied a compressed-sensing algorithm to image a synthetic fault model using dense and sparse acquisition geometries. Tests on synthetic data demonstrate the ability of compressed-sensing to produce highly resolved migrated images. We, also, studied the robustness of the Basis Pursuit algorithm in the presence of Gaussian random noise.

  8. The possibilities of compressed sensing based migration

    KAUST Repository

    Aldawood, Ali; Hoteit, Ibrahim; Alkhalifah, Tariq Ali

    2013-01-01

    Linearized waveform inversion or Least-square migration helps reduce migration artifacts caused by limited acquisition aperture, coarse sampling of sources and receivers, and low subsurface illumination. However, leastsquare migration, based on L2-norm minimization of the misfit function, tends to produce a smeared (smoothed) depiction of the true subsurface reflectivity. Assuming that the subsurface reflectivity distribution is a sparse signal, we use a compressed-sensing (Basis Pursuit) algorithm to retrieve this sparse distribution from a small number of linear measurements. We applied a compressed-sensing algorithm to image a synthetic fault model using dense and sparse acquisition geometries. Tests on synthetic data demonstrate the ability of compressed-sensing to produce highly resolved migrated images. We, also, studied the robustness of the Basis Pursuit algorithm in the presence of Gaussian random noise.

  9. Multicore Considerations for Legacy Flight Software Migration

    Science.gov (United States)

    Vines, Kenneth; Day, Len

    2013-01-01

    In this paper we will discuss potential benefits and pitfalls when considering a migration from an existing single core code base to a multicore processor implementation. The results of this study present options that should be considered before migrating fault managers, device handlers and tasks with time-constrained requirements to a multicore flight software environment. Possible future multicore test bed demonstrations are also discussed.

  10. Sparse least-squares reverse time migration using seislets

    KAUST Repository

    Dutta, Gaurav

    2015-08-19

    We propose sparse least-squares reverse time migration (LSRTM) using seislets as a basis for the reflectivity distribution. This basis is used along with a dip-constrained preconditioner that emphasizes image updates only along prominent dips during the iterations. These dips can be estimated from the standard migration image or from the gradient using plane-wave destruction filters or structural tensors. Numerical tests on synthetic datasets demonstrate the benefits of this method for mitigation of aliasing artifacts and crosstalk noise in multisource least-squares migration.

  11. Plane-wave least-squares reverse-time migration

    KAUST Repository

    Dai, Wei

    2013-06-03

    A plane-wave least-squares reverse-time migration (LSRTM) is formulated with a new parameterization, where the migration image of each shot gather is updated separately and an ensemble of prestack images is produced along with common image gathers. The merits of plane-wave prestack LSRTM are the following: (1) plane-wave prestack LSRTM can sometimes offer stable convergence even when the migration velocity has bulk errors of up to 5%; (2) to significantly reduce computation cost, linear phase-shift encoding is applied to hundreds of shot gathers to produce dozens of plane waves. Unlike phase-shift encoding with random time shifts applied to each shot gather, plane-wave encoding can be effectively applied to data with a marine streamer geometry. (3) Plane-wave prestack LSRTM can provide higher-quality images than standard reverse-time migration. Numerical tests on the Marmousi2 model and a marine field data set are performed to illustrate the benefits of plane-wave LSRTM. Empirical results show that LSRTM in the plane-wave domain, compared to standard reversetime migration, produces images efficiently with fewer artifacts and better spatial resolution. Moreover, the prestack image ensemble accommodates more unknowns to makes it more robust than conventional least-squares migration in the presence of migration velocity errors. © 2013 Society of Exploration Geophysicists.

  12. A foraging cost of migration for a partially migratory cyprinid fish

    DEFF Research Database (Denmark)

    Chapman, Ben B; Eriksen, Anders; Baktoft, Henrik

    2013-01-01

    Rutilus rutilus, which migrates from shallow lakes to streams during winter. By sampling fish from stream and lake habitats in the autumn and spring and measuring their stomach fullness and diet composition, we tested if migrating roach pay a cost of reduced foraging when migrating. Resident fish had...... fuller stomachs containing more high quality prey items than migrant fish. Hence, we document a feeding cost to migration in roach, which adds additional support for the validity of the p/g model of migration in freshwater systems....

  13. Random migration processes between two stochastic epidemic centers.

    Science.gov (United States)

    Sazonov, Igor; Kelbert, Mark; Gravenor, Michael B

    2016-04-01

    We consider the epidemic dynamics in stochastic interacting population centers coupled by random migration. Both the epidemic and the migration processes are modeled by Markov chains. We derive explicit formulae for the probability distribution of the migration process, and explore the dependence of outbreak patterns on initial parameters, population sizes and coupling parameters, using analytical and numerical methods. We show the importance of considering the movement of resident and visitor individuals separately. The mean field approximation for a general migration process is derived and an approximate method that allows the computation of statistical moments for networks with highly populated centers is proposed and tested numerically. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Mechanism of constitution liquid film migration

    Energy Technology Data Exchange (ETDEWEB)

    Zuo, Hongjun [Univ. of Alabama, Birmingham, AL (United States)

    1999-06-01

    Liquid film migration (LFM) in liquid phase sintering classically involves a large metastable liquid volume adjacent to solid, and migration occurs at an isolated solid-liquid (S-L) interface. Constitutional liquid film migration (CLFM), discovered in alloy 718, has major characteristics similar to those of LFM, except that the metastable liquid is from the constitutional liquation of precipitates on the grain boundary. The similarity between LFM and CLFM has led to the theory that coherency lattice strain responsible for LFM is also responsible for CLFM. The coherency strain hypothesis was tested in this study by evaluating whether the Hillert model of LFM would also apply for CLFM. Experimental results of CLFM in alloy 718 showed that migration velocity followed the trend predicted by the Hillert model. This indicates that the coherency strain hypothesis of LFM also applies for CLFM and that the coherency lattice strain responsible for LFM is also the driving force for CLFM.

  15. Cyclic grain boundary migration during high temperature fatigue--I: microstructural observations

    International Nuclear Information System (INIS)

    Langdon, T.G.; Gifkins, R.S.

    1983-01-01

    Experiments were conducted on high purity lead at room temperature using reverse bending and torsion fatigue at low cyclic frequencies (less than or equal to1.50 Hz). Metallographic observations after testing show that there is a one-to-one correspondence between the markings from grain boundary migration and the number and pattern of cyclic loading, and this correspondence is maintained up to >100 cycles. Grain boundary sliding occurs in each cycle in addition to the migration, and this leads to the development of broad triple point folds. If the strain amplitude is maintained constant, it is shown that the average distance migrated in each cycle increases as the imposed frequency is decreased. The distance migrated is often exceptionally large in the first cycle of testing, and there is often a similar large initial displacement if the test is interrupted for periods of time from 1 to 24 h and then continued. For large grain sizes (greater than or equal to 2000μm), the migration markings may lead to a zig-zag pattern where the individual segments lie fairly close to 45 0 to the stress axis. A model is described which accounts for the one-to-one correspondence and which is consistent with a fine structure observed within the migration markings

  16. The physiological basis of the migration continuum in brown trout ( Salmo trutta)

    DEFF Research Database (Denmark)

    Boel, Mikkel; Aarestrup, Kim; Baktoft, Henrik

    2014-01-01

    Partial migration is common in many animal taxa; however, the physiological variation underpinning migration strategies remains poorly understood. Among salmonid fishes, brown trout (Salmo trutta) is one of the species that exhibits the most complex variation in sympatric migration strategies......, expressed as a migration continuum, ranging from residency to anadromy. In looking at brown trout, our objective with this study was to test the hypothesis that variation in migration strategies is underpinned by physiological variation. Prior to migration, physiological samples were taken from fish...... in brown trout....

  17. Nuclear waste repository simulation experiments (brine migration), Asse Mine of the Federal Republic of Germany: Quarterly brine migration data report, October--December 1985

    International Nuclear Information System (INIS)

    Eckert, J.L.; Kalia, H.N.; Coyle, A.J.

    1988-03-01

    The tenth brine migration data report describes experiments simulating a nuclear waste repository at the 800-m (2624-ft) level of the Asse Salt Mine in the Federal Republic of Germany from May 1983 through December 1985. This report describes the test equipment, the Asse Salt Mine, and the pretest properties of the salt in the test gallery. This report includes test data for 31 months of operations on brine migration rates, borehole pressure, salt temperatures and thermomechanical behavior of the salt. 3 refs., 118 figs., 93 tabs

  18. Modeling Quasi-Static and Fatigue-Driven Delamination Migration

    Science.gov (United States)

    De Carvalho, N. V.; Ratcliffe, J. G.; Chen, B. Y.; Pinho, S. T.; Baiz, P. M.; Tay, T. E.

    2014-01-01

    An approach was proposed and assessed for the high-fidelity modeling of progressive damage and failure in composite materials. It combines the Floating Node Method (FNM) and the Virtual Crack Closure Technique (VCCT) to represent multiple interacting failure mechanisms in a mesh-independent fashion. Delamination, matrix cracking, and migration were captured failure and migration criteria based on fracture mechanics. Quasi-static and fatigue loading were modeled within the same overall framework. The methodology proposed was illustrated by simulating the delamination migration test, showing good agreement with the available experimental data.

  19. Investigation of organic matter migrating from polymeric pipes into drinking water under different flow manners.

    Science.gov (United States)

    Zhang, Ling; Liu, Shuming; Liu, Wenjun

    2014-02-01

    Polymeric pipes, such as unplasticized polyvinyl chloride (uPVC) pipes, polypropylene random (PPR) pipes and polyethylene (PE) pipes are increasingly used for drinking water distribution lines. Plastic pipes may include some additives like metallic stabilizers and other antioxidants for the protection of the material during its production and use. Thus, some compounds can be released from those plastic pipes and cast a shadow on drinking water quality. This work develops a new procedure to investigate three types of polymer pipes (uPVC, PE and PPR) with respect to the migration of total organic carbon (TOC) into drinking water. The migration test was carried out in stagnant conditions with two types of migration processes, a continuous migration process and a successive migration process. These two types of migration processes are specially designed to mimic the conditions of different flow manners in drinking water pipelines, i.e., the situation of continuous stagnation with long hydraulic retention times and normal flow status with regular water renewing in drinking water networks. The experimental results showed that TOC release differed significantly with different plastic materials and under different flow manners. The order of materials with respect to the total amount of TOC migrating into drinking water was observed as PE > PPR > uPVC under both successive and continuous migration conditions. A higher amount of organic migration from PE and PPR pipes was likely to occur due to more organic antioxidants being used in pipe production. The results from the successive migration tests indicated the trend of the migration intensity of different pipe materials over time, while the results obtained from the continuous migration tests implied that under long stagnant conditions, the drinking water quality could deteriorate quickly with the consistent migration of organic compounds and the dramatic consumption of chlorine to a very low level. Higher amounts of TOC

  20. Migration of ATLAS PanDA to CERN

    International Nuclear Information System (INIS)

    Stewart, Graeme Andrew; Klimentov, Alexei; Maeno, Tadashi; Nevski, Pavel; Nowak, Marcin; De Castro Faria Salgado, Pedro Emanuel; Wenaus, Torre; Koblitz, Birger; Lamanna, Massimo

    2010-01-01

    The ATLAS Production and Distributed Analysis System (PanDA) is a key component of the ATLAS distributed computing infrastructure. All ATLAS production jobs, and a substantial amount of user and group analysis jobs, pass through the PanDA system, which manages their execution on the grid. PanDA also plays a key role in production task definition and the data set replication request system. PanDA has recently been migrated from Brookhaven National Laboratory (BNL) to the European Organization for Nuclear Research (CERN), a process we describe here. We discuss how the new infrastructure for PanDA, which relies heavily on services provided by CERN IT, was introduced in order to make the service as reliable as possible and to allow it to be scaled to ATLAS's increasing need for distributed computing. The migration involved changing the backend database for PanDA from MySQL to Oracle, which impacted upon the database schemas. The process by which the client code was optimised for the new database backend is discussed. We describe the procedure by which the new database infrastructure was tested and commissioned for production use. Operations during the migration had to be planned carefully to minimise disruption to ongoing ATLAS offline computing. All parts of the migration were fully tested before commissioning the new infrastructure and the gradual migration of computing resources to the new system allowed any problems of scaling to be addressed.

  1. Evaluation of gas migration characteristics of compacted and saturated Ca-bentonite mixture

    International Nuclear Information System (INIS)

    Tanaka, Yukihisa; Hironaga, Michihiko

    2014-01-01

    In the current concept of near-surface pit disposal for low level radioactive waste, compacted bentonite mixture will be used as an engineered barrier mainly for inhibiting migration of radioactive nuclides. Hydrogen gas can be generated inside the engineered barrier mainly by the chemical interaction between aluminum and the alkaline component of cement, or water. If the gas generation rate exceeds the diffusion rate of gas molecules inside of the compacted bentonite mixture, gas will accumulate in the void space inside of the compacted bentonite mixture until its pressure becomes large enough for it to enter the compacted bentonite mixture as a discrete gaseous phase. It is expected to be not easy for gas to entering into the compacted bentonite mixture as a discrete gaseous phase because the pore of the compacted bentonite mixture is so minute. Therefore in this study, the gas migration characteristics and the effect of gas migration on the hydraulic conductivity of the compacted Ca-bentonite mixture are investigated by the gas migration tests. The effect of stress state on the migration characteristics is also investigated by the gas migration tests and by parametric study using the model of two phase flow through deformable porous media, which was originally developed by CRIEPI. Results of this study imply that : (1) Large gas breakthrough pressure, which is defined as a rapid increase of amount of discharged gas, is affected by initial stress conditions as well as Ca-bentonite content of the mixture. (2) Hydraulic conductivity measured after the large gas breakthrough is substantially the same that measured before the gas migration test. (3) Axial stress change and volume change of the specimen during the gas migration test can be reproduced by the numerical simulation using the model of two-phase flow through deformable porous media, which was originally developed by CRIEPI. (4) Gas migration of a small scale model is numerically simulated to investigate the

  2. Chemotactic Activity of Cyclophilin A in the Skin Mucus of Yellow Catfish (Pelteobagrus fulvidraco) and Its Active Site for Chemotaxis

    Science.gov (United States)

    Dawar, Farman Ullah; Tu, Jiagang; Xiong, Yang; Lan, Jiangfeng; Dong, Xing Xing; Liu, Xiaoling; Khattak, Muhammad Nasir Khan; Mei, Jie; Lin, Li

    2016-01-01

    Fish skin mucus is a dynamic barrier for invading pathogens with a variety of anti-microbial enzymes, including cyclophilin A (CypA), a multi-functional protein with peptidyl-prolyl cis/trans isomerase (PPIase) activity. Beside various other immunological functions, CypA induces leucocytes migration in vitro in teleost. In the current study, we have discovered several novel immune-relevant proteins in yellow catfish skin mucus by mass spectrometry (MS). The CypA present among them was further detected by Western blot. Moreover, the CypA present in the skin mucus displayed strong chemotactic activity for yellow catfish leucocytes. Interestingly, asparagine (like arginine in mammals) at position 69 was the critical site in yellow catfish CypA involved in leucocyte attraction. These novel efforts do not only highlight the enzymatic texture of skin mucus, but signify CypA to be targeted for anti-inflammatory therapeutics. PMID:27589721

  3. Chemotactic Activity of Cyclophilin A in the Skin Mucus of Yellow Catfish (Pelteobagrus fulvidraco and Its Active Site for Chemotaxis

    Directory of Open Access Journals (Sweden)

    Farman Ullah Dawar

    2016-08-01

    Full Text Available Fish skin mucus is a dynamic barrier for invading pathogens with a variety of anti-microbial enzymes, including cyclophilin A (CypA, a multi-functional protein with peptidyl-prolyl cis/trans isomerase (PPIase activity. Beside various other immunological functions, CypA induces leucocytes migration in vitro in teleost. In the current study, we have discovered several novel immune-relevant proteins in yellow catfish skin mucus by mass spectrometry (MS. The CypA present among them was further detected by Western blot. Moreover, the CypA present in the skin mucus displayed strong chemotactic activity for yellow catfish leucocytes. Interestingly, asparagine (like arginine in mammals at position 69 was the critical site in yellow catfish CypA involved in leucocyte attraction. These novel efforts do not only highlight the enzymatic texture of skin mucus, but signify CypA to be targeted for anti-inflammatory therapeutics.

  4. Surface coating for prevention of metallic seed migration in tissues

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyunseok; Park, Jong In [Program in Biomedical Radiation Sciences, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, Won Seok; Park, Min [Interdisciplinary Program in Bioengineering, Seoul National University College of Engineering, Seoul 151-742 (Korea, Republic of); Son, Kwang-Jae [Hanaro Applications Research, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Bang, Young-bong [Advanced Institutes of Convergence Technology, Seoul National University, Suwon 443-270 (Korea, Republic of); Choy, Young Bin, E-mail: ybchoy@snu.ac.kr, E-mail: sye@snu.ac.kr [Interdisciplinary Program in Bioengineering, Seoul National University College of Engineering, Seoul 110-744 (Korea, Republic of); Department of Biomedical Engineering, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Institute of Medical and Biological Engineering, Medical Research Center, Seoul National University, Seoul 110-744 (Korea, Republic of); Ye, Sung-Joon, E-mail: ybchoy@snu.ac.kr, E-mail: sye@snu.ac.kr [Program in Biomedical Radiation Sciences, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 151-742 (Korea, Republic of); Advanced Institutes of Convergence Technology, Seoul National University, Suwon 443-270 (Korea, Republic of); Department of Radiation Oncology, Seoul National University Hospital, Seoul 110-744 (Korea, Republic of)

    2015-06-15

    Purpose: In radiotherapy, metallic implants often detach from their deposited sites and migrate to other locations. This undesirable migration could cause inadequate dose coverage for permanent brachytherapy and difficulties in image-guided radiation delivery for patients. To prevent migration of implanted seeds, the authors propose a potential strategy to use a biocompatible and tissue-adhesive material called polydopamine. Methods: In this study, nonradioactive dummy seeds that have the same geometry and composition as commercial I-125 seeds were coated in polydopamine. Using scanning electron microscopy and x-ray photoelectron spectroscopy, the surface of the polydopamine-coated and noncoated seeds was characterized. The detachment stress between the two types of seeds and the tissue was measured. The efficacy of polydopamine-coated seed was investigated through in vitro migration tests by tracing the seed location after tissue implantation and shaking for given times. The cytotoxicity of the polydopamine coating was also evaluated. Results: The results of the coating characterization have shown that polydopamine was successfully coated on the surface of the seeds. In the adhesion test, the polydopamine-coated seeds had 2.1-fold greater detachment stress than noncoated seeds. From the in vitro test, it was determined that the polydopamine-coated seed migrated shorter distances than the noncoated seed. This difference was increased with a greater length of time after implantation. Conclusions: The authors suggest that polydopamine coating is an effective technique to prevent migration of implanted seeds, especially for permanent prostate brachytherapy.

  5. Kinetics of prostaglandin E2 and thromboxane A2 synthesis and suppression of PHA-stimulated peripheral blood mononuclear leucocytes.

    Science.gov (United States)

    Awara, W; Hillier, K; Jones, D

    1986-12-01

    The immunomodulatory effects of thromboxane A2 and prostaglandin E2 on peripheral blood mononuclear leucocytes stimulated with PHA in vitro, and the relationship of this to the time-course of their synthesis in culture, were investigated using prostaglandin E2, a thromboxane A2 synthesis inhibitor (UK37248), a thromboxane A2 mimic (U46619) and a thromboxane A2 receptor blocker (EP045). The inhibitory effect of prostaglandin E2 on PHA-induced human peripheral blood mononuclear leucocyte proliferation diminishes if the addition of PGE2 is delayed. If added 4 hr after a maximum concentration of PHA (5 micrograms/ml), the effect of PGE2 was reduced by 60%. If a submaximal concentration of PHA (1 microgram/ml) was used, the effect of PGE2 was not reduced if added 4 hr later but fell by about 60% after 16 hr. UK37248 moderately inhibited PHA-induced activation while substantially inhibiting thromboxane A2 synthesis and simultaneously enhancing PGE2 synthesis. The enhanced accumulation of PGE2 occurs while sensitivity to PGE2 is dropping. U46619, exogenously applied as a thromboxane A2 mimic, inhibited PHA-induced activation at concentrations that did not significantly alter PGE2 synthesis. EP045, which may modulate the effects of endogenous thromboxane A2 by blocking receptors, did not alter PHA-induced activation. We conclude that thromboxane A2 may have a role in inhibiting PHA-induced activation on the basis of the effect of U46619. However, this study highlights difficulties in utilizing prostaglandin and thromboxane receptor and synthesis inhibitors to examine their endogenous role in the modulation of mitogen-induced activation in vitro. If sensitivity to the purported endogenous substance is limited to the early stages of culture and if only low levels are synthesized at this early stage, then blocking drugs would have little effect.

  6. Short-term organic carbon migration from polymeric materials in contact with chlorinated drinking water.

    Science.gov (United States)

    Mao, Guannan; Wang, Yingying; Hammes, Frederik

    2018-02-01

    Polymeric materials are widely used in drinking water distribution systems. These materials could release organic carbon that supports bacterial growth. To date, the available migration assays for polymeric materials have not included the potential influence of chlorination on organic carbon migration behavior. Hence, we established a migration and growth potential protocol specifically for analysis of carbon migration from materials in contact with chlorinated drinking water. Four different materials were tested, including ethylene propylene dienemethylene (EPDM), poly-ethylene (PEX b and PEX c) and poly-butylene (PB). Chlorine consumption rates decreased gradually over time for EPDM, PEXc and PB. In contrast, no free chlorine was detected for PEXb at any time during the 7 migration cycles. Total organic carbon (TOC) and assimilable organic carbon (AOC) was evaluated in both chlorinated and non-chlorinated migrations. TOC concentrations for EPDM and PEXb in chlorinated migrations were significantly higher than non-chlorinated migrations. The AOC results showed pronounced differences among tested materials. AOC concentrations from chlorinated migration waters of EPDM and PB were higher compared to non-chlorinated migrations, whereas the opposite trend was observed for PEXb and PEXc. There was also a considerable difference between tested materials with regards to bacterial growth potential. The results revealed that the materials exposed to chlorine-influenced migration still exhibited a strong biofilm formation potential. The overall results suggested that the choice in material would make a considerable difference in chlorine consumption and carbon migration behavior in drinking water distribution systems. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Recent drilling program to investigate radionuclide migration at the Nevada Test Site

    International Nuclear Information System (INIS)

    Smith, D.K.

    1997-01-01

    Recent drilling affords new opportunities to investigate the occurrence, distribution and transport of radionuclides in the unsaturated and saturated zone at the Nevada Test Site (NTS), Nye County, Nevada. This program is unique becmise of the elevated activities of radionuclides encountered during drilling (> 3.7E+6 Bq/L 3H), extreme completion depths (> 950 m), the expense of constructing new wells (> $IE+6/borehole), and collaboration of government, academic, and industrial partners in the planning and execution of the program. The recent chilling is significant because it substantively augments earlier field of radionuclide migration at NTS, most notably the 1974 CAMBRIC RNM experiment Sites of five nuclear tests fired below or adjacent to the saturated zone have been drilled. Three of the events were fired in Yucca Flat which is a hydrologically closed basin and two were fired in fractured volcanics of Pahute Mesa. Results from Yucca Flat indicate that volatile and refractory radionuclides, fractionated at zero time, we not highly mobile under sawmted conditions. In contrast, borcholes completed on Pahute Mesa indicate Wgh concentrations of tritium (> 3.7E+6 Bq/L 3H) and other radionuclides may be rted more than 300 m from event cavities as dissolved species or as colloids

  8. Recent drilling program to investigate radionuclide migration at the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.K.

    1997-04-01

    Recent drilling affords new opportunities to investigate the occurrence, distribution and transport of radionuclides in the unsaturated and saturated zone at the Nevada Test Site (NTS), Nye County, Nevada. This program is unique becmise of the elevated activities of radionuclides encountered during drilling (> 3.7E+6 Bq/L 3H), extreme completion depths (> 950 m), the expense of constructing new wells (> $IE+6/borehole), and collaboration of government, academic, and industrial partners in the planning and execution of the program. The recent chilling is significant because it substantively augments earlier field of radionuclide migration at NTS, most notably the 1974 CAMBRIC RNM experiment Sites of five nuclear tests fired below or adjacent to the saturated zone have been drilled. Three of the events were fired in Yucca Flat which is a hydrologically closed basin and two were fired in fractured volcanics of Pahute Mesa. Results from Yucca Flat indicate that volatile and refractory radionuclides, fractionated at zero time, we not highly mobile under sawmted conditions. In contrast, borcholes completed on Pahute Mesa indicate Wgh concentrations of tritium (> 3.7E+6 Bq/L 3H) and other radionuclides may be rted more than 300 m from event cavities as dissolved species or as colloids.

  9. Polymorphonuclear leucocyte dysfunction during short term metabolic changes from normo- to hyperglycemia in type 1 (insulin dependent) diabetic patients

    DEFF Research Database (Denmark)

    Kjersem, H; Hilsted, J; Madsbad, S

    1988-01-01

    Polymorphonuclear leucocyte (PMN) ingestion of particles coated with lipopolysaccharide (LPS) from Escherichia coli was compared to other PMN functions in seven patients with insulin dependent diabetes mellitus (IDDM) during short-term controlled metabolic changes from normo- to hyperglycemia...... without ketoacidosis. Factors known to interfere with PMN functions were excluded. PMN ingestion of particles coated with both LPS and bovine serum albumin became reduced from normo- to hyperglycemia. PMN motility was impaired in IDDM, but did not seem to be affected by short-term changes in metabolic...... control. PMN metabolism did not change from normo-to hyperglycemia. Particle-uptake by diabetic PMN is impaired after short term hyperglycemia in the range normally occurring in diabetics in every-day life....

  10. Gas migration mechanism of saturated dense bentonite and its modeling

    International Nuclear Information System (INIS)

    Tanaka, Yukihisa; Hironaga, Michihiko; Kudo, Koji

    2007-01-01

    In the current concept of repository for nuclear waste disposal, compacted bentonite will be used as an engineered barrier mainly for inhibiting migration of radioactive nuclides. Hydrogen gas can be generated inside the engineered barrier by anaerobic corrosion of metals used for containers, etc. If the gas generation rate exceeds the diffusion rate of gas molecules inside of the engineered barrier, gas will accumulate in the void space inside of the engineered barrier until its pressure becomes large enough for it to enter the bentonite as a discrete gaseous phase. It is expected to be not easy for gas to entering into the bentonite as a discrete gaseous phase because the pore of compacted bentonite is so minute. Therefore it is necessary to investigate the following subjects: a) Effect of the accumulated gas pressure on surrounding objects such as concrete lining, rock mass. b) Effect of gas breakthrough on the barrier function of bentonite. c) Revealing and modeling gas migration mechanism for overcoming the scale effects in laboratory specimen test. Therefore in this study, gas migration tests for compacted and saturated bentonite to investigate and to model the mechanism of gas migration phenomenon. Firstly, the following conclusions were obtained through by the results of the gas migration tests which are conducted in this study: 1) Bubbles appear in the semitransparent drainage tube at first when the total gas is equal to the initial total axial stress or somewhat smaller. By increasing the gas pressure more, breakthrough of gas migration, which is defined as a sudden increase of amount of emission gas, occurred. When the total gas pressure exceeds the initial total axial stress, the total axial stress is always equal to the total gas pressure because specimens shrink in the axial direction with causing the clearance between the end of the specimen and porous metal. 2) Effective gas conductivity after breakthrough of gas migration is times larger than that

  11. International Migration with Heterogeneous Agents: Theory and Evidence for Germany, 1967-2009

    DEFF Research Database (Denmark)

    Brücker, Herbert; Schröder, Philipp

    2012-01-01

    Temporary migration, though empirically relevant, is often ignored in formal models. This paper proposes a migration model with heterogeneous agents and persistent cross country income differentials that features temporary migration. In equilibrium there exists a positive relation between the stock...... of migrants and the income differential, while the net migration flow becomes zero. Consequently, existing empirical migration models, estimating net migration flows, instead of stocks, may be misspecified. This suspicion appears to be confirmed by our investigation of the cointegration relationships...... of German migration stocks and flows since 1967. We find that (i) panel-unit root tests reject the hypothesis that migration flows and the explanatory variables are integrated of the same order, while migration stocks and the explanatory variables are all I(1) variables, and (ii) the hypothesis...

  12. Family migration and employment: the importance of migration history and gender.

    Science.gov (United States)

    Bailey, A J; Cooke, T J

    1998-01-01

    "This article uses event history data to specify a model of employment returns to initial migration, onward migration, and return migration among newly married persons in the U.S. Husbands are more likely to be full-time employed than wives, and being a parent reduces the employment odds among married women. Employment returns to repeated migration differ by gender, with more husbands full-time employed after onward migration and more wives full-time employed after return migration events. We interpret these empirical findings in the context of family migration theory, segmented labor market theory, and gender-based responsibilities." Data are from the National Longitudinal Survey of Youth from 1979 to 1991. excerpt

  13. Migration of particulates in permeable rock columns

    International Nuclear Information System (INIS)

    Cropper, R.L.

    1982-01-01

    The migration of radioactive material through soil and permeable rock formations have become a major topic of concern due to the interest in the licensing of new radioactive waste disposal sites. Previously, research has been conducted in relation to deep repositories; however, similar situations arise in the vadose zone, where there is a higher probability of naturally-occurring particulates of organic nature and for the incursion of water. Test data has provided information which suggests that particulates will travel through porous media subject to various delay mechnisms and must be included in any consideration of waste migration. Data concerning particulate migration must and should be considered in the future when radioactive waste disposal sites are licensed

  14. Regularized plane-wave least-squares Kirchhoff migration

    KAUST Repository

    Wang, Xin

    2013-09-22

    A Kirchhoff least-squares migration (LSM) is developed in the prestack plane-wave domain to increase the quality of migration images. A regularization term is included that accounts for mispositioning of reflectors due to errors in the velocity model. Both synthetic and field results show that: 1) LSM with a reflectivity model common for all the plane-wave gathers provides the best image when the migration velocity model is accurate, but it is more sensitive to the velocity errors, 2) the regularized plane-wave LSM is more robust in the presence of velocity errors, and 3) LSM achieves both computational and IO saving by plane-wave encoding compared to shot-domain LSM for the models tested.

  15. A preference for migration

    OpenAIRE

    Stark, Oded

    2007-01-01

    At least to some extent migration behavior is the outcome of a preference for migration. The pattern of migration as an outcome of a preference for migration depends on two key factors: imitation technology and migration feasibility. We show that these factors jointly determine the outcome of a preference for migration and we provide examples that illustrate how the prevalence and transmission of a migration-forming preference yield distinct migration patterns. In particular, the imitation of...

  16. Migration of TRU-containing slag into candidate refractories for waste management

    International Nuclear Information System (INIS)

    Seymour, W.C.

    1978-11-01

    Results of initial tests on transuranic migration into commercial refractories are reported. Five castable refractories and a plastic-bonded refractory were tested using the cup test method. Initial results indicate that castable materials will not survive conditions expected in the slagging pyrolysis unit; plastic refractories appear to have better performance. The major mechanism of migration into the tested refractories is pore penetration. Al 2 O 3 and Al 2 O 3 -Cr 2 O 3 phases appear resistant to chemical diffusion of transuranics. 2 figures, 16 tables

  17. Migration check tool: automatic plan verification following treatment management systems upgrade and database migration.

    Science.gov (United States)

    Hadley, Scott W; White, Dale; Chen, Xiaoping; Moran, Jean M; Keranen, Wayne M

    2013-11-04

    Software upgrades of the treatment management system (TMS) sometimes require that all data be migrated from one version of the database to another. It is necessary to verify that the data are correctly migrated to assure patient safety. It is impossible to verify by hand the thousands of parameters that go into each patient's radiation therapy treatment plan. Repeating pretreatment QA is costly, time-consuming, and may be inadequate in detecting errors that are introduced during the migration. In this work we investigate the use of an automatic Plan Comparison Tool to verify that plan data have been correctly migrated to a new version of a TMS database from an older version. We developed software to query and compare treatment plans between different versions of the TMS. The same plan in the two TMS systems are translated into an XML schema. A plan comparison module takes the two XML schemas as input and reports any differences in parameters between the two versions of the same plan by applying a schema mapping. A console application is used to query the database to obtain a list of active or in-preparation plans to be tested. It then runs in batch mode to compare all the plans, and a report of success or failure of the comparison is saved for review. This software tool was used as part of software upgrade and database migration from Varian's Aria 8.9 to Aria 11 TMS. Parameters were compared for 358 treatment plans in 89 minutes. This direct comparison of all plan parameters in the migrated TMS against the previous TMS surpasses current QA methods that relied on repeating pretreatment QA measurements or labor-intensive and fallible hand comparisons.

  18. Facilitators and constraints at each stage of the migration decision process.

    Science.gov (United States)

    Kley, Stefanie

    2017-10-01

    Behavioural models of migration emphasize the importance of migration decision-making for the explanation of subsequent behaviour. But empirical migration research regularly finds considerable gaps between those who intend to migrate and those who actually realize their intention. This paper applies the Theory of Planned Behaviour, enriched by the Rubicon model, to test specific hypotheses about distinct effects of facilitators and constraints on specific stages of migration decision-making and behaviour. The data come from a tailor-made panel survey based on random samples of people drawn from two German cities in 2006-07. The results show that in conventional models the effects of facilitators and constraints on migration decision-making are likely to be underestimated. Splitting the process of migration decision-making into a pre-decisional and a pre-actional phase helps to avoid bias in the estimated effects of facilitators and constraints on both migration decision-making and migration behaviour.

  19. Field-scale colloid migration experiments in a granite fracture

    International Nuclear Information System (INIS)

    Vilks, P.; Frost, L.H.; Bachinski, D.B.

    1997-01-01

    An understanding of particle migration in fractured rock, required to assess the potential for colloid-facilitated transport of radionuclides, can best be evaluated when the results of laboratory experiments are demonstrated in the field. Field-scale migration experiments with silica colloids were carried out at AECL's Underground Research Laboratory (URL), located in southern Manitoba, to develop the methodology for large-scale migration experiments and to determine whether colloid transport is possible over distances up to 17 m. In addition, these experiments were designed to evaluate the effects of flow rate and flow path geometry, and to determine whether colloid tracers could be used to provide additional information on subsurface transport to that provided by conservative tracers alone. The colloid migration studies were carried out as part of AECL's Transport Properties in Highly Fractured Rock Experiment, the objective of which was to develop and demonstrate methods for evaluating the solute transport characteristics of zones of highly fractured rock. The experiments were carried out within fracture zone 2 as two-well recirculating, two-well non-recirculating, and convergent flow tests, using injection rates of 5 and 101 min -1 . Silica colloids with a 20 nm size were used because they are potentially mobile due to their stability, small size and negative surface charge. The shapes of elution profiles for colloids and conservative tracers were similar, demonstrating that colloids can migrate over distances of 17 m. The local region of drawdown towards the URL shaft affected colloid migration and, to a lesser extent, conservative tracer migration within the flow field established by the two-well tracer tests. These results indicate that stable colloids, with sizes as small as 20 nm, have different migration properties from dissolved conservative tracers. (author)

  20. Linguistic Phylogenies Support Back-Migration from Beringia to Asia

    Science.gov (United States)

    Sicoli, Mark A.; Holton, Gary

    2014-01-01

    Recent arguments connecting Na-Dene languages of North America with Yeniseian languages of Siberia have been used to assert proof for the origin of Native Americans in central or western Asia. We apply phylogenetic methods to test support for this hypothesis against an alternative hypothesis that Yeniseian represents a back-migration to Asia from a Beringian ancestral population. We coded a linguistic dataset of typological features and used neighbor-joining network algorithms and Bayesian model comparison based on Bayes factors to test the fit between the data and the linguistic phylogenies modeling two dispersal hypotheses. Our results support that a Dene-Yeniseian connection more likely represents radiation out of Beringia with back-migration into central Asia than a migration from central or western Asia to North America. PMID:24621925

  1. The causes of international labor migrations--a demand-determined approach.

    Science.gov (United States)

    Straubhaar, T

    1986-01-01

    The author first studies the reasons why people migrate using a neoclassical approach concerning income differentials. He tests this approach empirically and demonstrates its limits. A demand-determination approach based on human capital theory is then outlined to overcome these limits and to take into account restrictive immigration controls. Migration from Italy, Spain, Greece, Portugal, and Turkey to the European Community destination countries is examined. It is concluded that "the demand for immigrants in the destination country is the decisive condition for the phenomenon of international labor migration, and the supply of migration-willing workers is only a necessary condition." excerpt

  2. Study of radionuclide migration in clay formations

    International Nuclear Information System (INIS)

    Antonioli, F.; Bocola, W.

    1985-01-01

    This paper reports the studies on the migration of Cs, Sr and I in clay formations, which are presently considered for the geological disposal of radioactive wastes. The distribution and diffusion coefficients were evaluated by means of experimental techniques and computer procedures, which are presented in this report. The natural clays tested in the laboratory experiments were sampled from the most representative italian basins and from the zone of Mol (Belgium). In addition tests were performed on monomineral clays artificially remade in edometer. The experimental results are in accordance with data found in the literature and show the existence of a good correlation between the observed migration properties and the granulometric and mineralogic characteristics of the natural clays

  3. Preservation of Bone-Marrow Cells, Leucocytes and Platelets at Low Temperatures. A Review

    Energy Technology Data Exchange (ETDEWEB)

    Ashwood-Smith, M. J. [Medical Research Council, Radiobiological Research Unit, Harwell, Berks. (United Kingdom)

    1969-07-15

    The basic principles of cryobiology are discussed and applications of these principles by numerous workers in attempts to preserve marrow cells, leucocytes and platelets at low temperatures are reviewed. It is concluded that: (1) Lymphocytes from animals and man can be stored for long periods of time at low temperatures when cooled slowly in 10-15% DMSO or glycerol and thawed rapidly. Recovery figures are high and function is intact and unaltered. DMSO is probably a better preservative than glycerol, and storage life at -196 Degree-Sign C is probably indefinite for all practical purposes. Other leucocytes can be stored with similar techniques but recoveries after freezing and thawing are probably lower than with lymphocytes. (2) Bone-marrow cells of several animals including mouse, rabbit and dog can be preserved at -196 Degree-Sign C, probably indefinitely, and similar procedures to those used for lymphocytes give the best results. The comprehensive studies of Lewis and Trobaugh indicate that under carefully controlled conditions 95% of the stem cells in mouse marrow are viable after freezing and thawing. Opinions are divided over the efficacy of the two preservatives, DMSO and glycerol, but in view of the well documented accounts of the lack of toxicity of glycerol it would seem advisable for the moment to use this agent with all human marrow samples. The usefulness of PVP as a preservative for marrow is still to be resolved. Human marrow after freezing and thawing probably behaves in a similar manner to mouse marrow both in vitro and in vivo. However, it would be wise to consider that there might be differences which could cause wrong assessments of freezing procedures. (3) Platelet preservation, clinically perhaps the most useful procedure discussed in this review, is still to a large extent in the experimental stage. Much work has been done but even the best methods available permit relatively low recoveries of viable platelets. Preservation of human platelets

  4. Estimates of potential radionuclide migration at the Bullion site

    International Nuclear Information System (INIS)

    Brikowski, T.H.

    1992-04-01

    The Bullion site in Area 20 of the Nevada Test Site has been selected for an intensive study of the hydrologic consequences of underground testing, including subsequent radionuclide migration. The bulk of the chimney and cavity lie in zeolitized tuffs of low hydraulic conductivity, while the base of the cavity may extend downward into more conductive rhyolite flows. A mathematical analog to the Bullion setting is used here to estimate expected radionuclide migration rates and concentrations. Because of a lack of hydrologic data at the site, two contrasting scenarios are considered. The first is downward-transport, in which downward hydraulic gradients flush chimney contents into the conductive underlying units, enhancing migration. The other is upward-transport, in which upward gradients tend to drive chimney contents into the low-conductivity zeolitized tuffs, discouraging migration. In the downward-transport scenario, radionuclide travel times and concentrations are predicted to be similar to those encountered at Cheshire, requiring approximately 10 years to reach a proposed well 300 m downgradient. The upward transport scenario yields predicted travel times on the order of 2,000 years to the downgradient well. The most likely scenario is a combination of these results, with vertical movement playing a limited role. Radionuclides injected directly into the rhyolites should migrate laterally very quickly, with travel times as in the downward-transport scenario. Those in the zeolitized tuff-walled portion of the chimney should migrate extremely slowly, as in the upward-transport scenario

  5. Study on experimental models to analyze radionuclide migration behaviors through porous geologic media

    International Nuclear Information System (INIS)

    Tanaka, Tadao; Mukai, Masayuki

    2012-08-01

    The migration phenomenon of radionuclide through geological media such as soils and porous rocks, which is important in underground disposal of radioactive wastes, can be described by the advection-dispersion of groundwater and the interactions of radionuclide with geological media. On the other hand, to understand the migration phenomenon, actual migration data are experimentally acquired by a batch test, a column test and field trial. In the present study, experimental models about the interactions of radionuclide between the solid phase and the liquid phase were discussed systematically to interpret the migration data acquired by the various techniques and conditions. Equilibrium, reversibility, linearity, mechanism and chemistry in the interactions were considered in discussion of the experimental models. A calculation program, which can analyze migration data obtained under various conditions by applying the selected 9 types of experimental models, was maintained. The calculation program makes it be able to predict the migration behavior of radionuclide under various conditions and to decide the important parameter by a fitting analysis of the migration data. (author)

  6. The CHESHIRE Migration Experiment A Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    David A. Sawyer; Joseph L. Thompson; David K. Smith

    1999-10-01

    The CHESHIRE nuclear weapon test was detonated in 1976 in fractured volcanic rock at the Nevada Test Site (NTS). This testis representative of many other high-yield tests conducted below the water table in the Pahute Mesa area of the NTS. Since 1976 we have been studying the movement of test-related radionuclides within a few hundred meters of the explosion cavity. CHESHIRE is the only nuclear test characterized before, immediately after, and for decades following the detonation and provides data on both the prompt and long-term dispersal of radionuclides after an underground nuclear test. For this reason it is a unique field-scale transport experiment. Solid and fluid samples were collected from a drill back hole extending into and through the cavity in order to measure the initial distributions of radionuclides after the detonation. We subsequently pumped and sampled water from the cavity region and from a hydraulically transmissive zone about 400 m higher in the collapse chimney. A satellite well was also drilled 380 m down gradient from CHESHIRE and intercepted radionuclides (including tritium in high concentration) being transported through transmissive aquifers. Studies of radionuclide migration at CHESHIRE documented for the first time at the NTS the transport of relatively insoluble radionuclides (e.g., europium isotopes) with colloids moving in the groundwater. Water was pumped again from the cavity and chimney horizons in 1998 in order to observe the evolution of the hydrologic source term after several decades. Recent comprehensive studies of the geology and hydrology at the CHESHIRE site have improved predictions of radionuclide migration in the context of a regional groundwater flow model. This report provides unclassified data and describes a conceptual model for radionuclide migration associated with a nuclear test that is applicable to other tests on Pahute Mesa similar in yield, hydrogeologic setting, and age.

  7. Japanese migration in contemporary Japan: economic segmentation and interprefectural migration.

    Science.gov (United States)

    Fukurai, H

    1991-01-01

    This paper examines the economic segmentation model in explaining 1985-86 Japanese interregional migration. The analysis takes advantage of statistical graphic techniques to illustrate the following substantive issues of interregional migration: (1) to examine whether economic segmentation significantly influences Japanese regional migration and (2) to explain socioeconomic characteristics of prefectures for both in- and out-migration. Analytic techniques include a latent structural equation (LISREL) methodology and statistical residual mapping. The residual dispersion patterns, for instance, suggest the extent to which socioeconomic and geopolitical variables explain migration differences by showing unique clusters of unexplained residuals. The analysis further points out that extraneous factors such as high residential land values, significant commuting populations, and regional-specific cultures and traditions need to be incorporated in the economic segmentation model in order to assess the extent of the model's reliability in explaining the pattern of interprefectural migration.

  8. Waste migration in shallow burial sites under unsaturated flow conditions

    International Nuclear Information System (INIS)

    Eicholz, G.G.; Whang, J.

    1987-01-01

    Unsaturated conditions prevail in many shallow-land burial sites, both in arid and humid regions. Unless a burial site is allowed to flood and possibly overflow, a realistic assessment of any migration scenario must take into account the conditions of unsaturated flow. These are more difficult to observe and to model, but introduce significant changes into projected rates of waste leaching and waste migration. Column tests have been performed using soils from the Southeastern coastal plain to observe the effects of varying degrees of ''unsaturation'' on the movement of radioactive tracers. The moisture content in the columns was controlled by maintaining various levels of hydrostatic suction on soil columns whose hydrodynamic characteristics had been determined carefully. Tracer tests, employing Cs-137, I-131 and Ba-133 were used to determine migration profiles and to follow their movement down the column for different suction values. A calculational model has been developed for unsaturated flow and seems to match the observations fairly well. It is evident that a full description of migration processes must take into account the reduced migration rates under unsaturated conditions and the hysteresis effects associated with wetting-drying cycles

  9. Quarterly brine migration data report, May-September 1983: Nuclear Waste Repository simulation experiments (brine migration), Asse Mine of the Federal Republic of Germany

    International Nuclear Information System (INIS)

    Coyle, A.J.; Kalia, H.N.; Eckert, J.L.

    1987-04-01

    The first quarterly brine migration data report describes experiments simulating a nuclear waste repository at the 800-m (2624-ft) level of the Asse Salt Mine in the Federal Republic of Germany from May 1983 through September 1983. This report describes the test equipment, the Asse Salt Mine, and the pretest properties of the salt in the test gallery. This report also includes test data for the first 4 months of operations on brine migration rates, borehole pressure, salt temperatures, and thermomechanical behavior of the salt. The duration of the experiments will be approximately 2 years, ending in December 1985. 83 figs., 55 tabs

  10. Migration of mineral oil from party plates of recycled paperboard into foods: 1. Is recycled paperboard fit for the purpose? 2. Adequate testing procedure.

    Science.gov (United States)

    Dima, Giovanna; Verzera, Antonella; Grob, Koni

    2011-11-01

    Party plates made of recycled paperboard with a polyolefin film on the food contact surface (more often polypropylene than polyethylene) were tested for migration of mineral oil into various foods applying reasonable worst case conditions. The worst case was identified as a slice of fried meat placed onto the plate while hot and allowed to cool for 1 h. As it caused the acceptable daily intake (ADI) specified by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) to be exceeded, it is concluded that recycled paperboard is generally acceptable for party plates only when separated from the food by a functional barrier. Migration data obtained with oil as simulant at 70°C was compared to the migration into foods. A contact time of 30 min was found to reasonably cover the worst case determined in food.

  11. Migration to Alma/Primo: A Case Study of Central Washington University

    Directory of Open Access Journals (Sweden)

    Ping Fu

    2015-12-01

    Full Text Available This paper describes how Central Washington University Libraries (CWUL interacted and collaborated with the Orbis Cascade Alliance (OCA Shared Integrated Library System’s (SILS Implementation Team and Ex Libris to process systems and data migration from Innovative Interfaces Inc.’s Millennium integrated library system to Alma/Primo, Ex Libris’ next-generation library management solution and discovery and delivery solution. A chronological review method was used for this case study to provide an overall picture of key migration events, tasks, and implementation efforts, including pre-migration cleanup, migration forms, integration with external systems, testing, cutover, post-migration cleanup, and reporting and fixing outstanding issues. A three-phase migration model was studied, and a questionnaire was designed to collect data from functional leads to determine staff time spent on the migration tasks. Staff time spent on each phase was analyzed and quantitated, with some top essential elements for the success of the migration identified through the case review and data analysis. An analysis of the Ex Libris’ Salesforce cases created during the migration and post-migration was conducted to be used for identifying roles of key librarians and staff functional leads during the migration.

  12. Review of a field study of radionuclide migration from an underground nuclear explosion at the Nevada Test Site

    International Nuclear Information System (INIS)

    Hoffman, D.C.; Daniels, W.R.; Wolfsberg, K.; Thompson, J.L.; Rundberg, R.S.; Fraser, S.L.; Daniels, K.S.

    1983-01-01

    Results from a long-term (9 year) field study of the distribution of radionuclides around an underground nuclear explosion cavity at the Nevada Test Site are reviewed. The goals of this Radionuclide Migration project are to examine the rates of migration underground in various media and to determine the potential for movement, both on and off the Nevada Test Site, of radioactivity from such explosions, with particular interest in possible contamination of water supplies. Initial studies were undertaken near the site of the low-yield test Cambric, which was detonated 73 m beneath the water table in tuffaceous alluvium. Solid samples were obtained from just below ground surface to 50 m below the detonation point, and water was sampled from five different regions in the vicinity of the explosion. Ten years after the test, most of the radioactivity was found to be retained in the fused debris in the cavity region and no activity above background was found 50 m below. Only tritium and 90 Sr were presented in water in the cavity at levels greater than recommended concentration guides for water in uncontrolled areas. A satellite well is being used to remove water 91 m from the detonation point. During seven years (7 x 10 6 m 3 ) of pumping, tritium, 85 Kr, 36 Cl, and 129 I have been detected in the water. Approximately 40% of the total tritium from the cavity region has been removed by pumping at the satellite well, and the maximum in the tritium concentration is clearly defined. Use of sensitive analytical techniques has permitted measurement of the very low concentrations of 36 Cl and 129 I present in the water. The 36 Cl peak precedes the tritiated water, possibly as a result of anion exclusion. Additional analyses are in progress to better define the shape of the 129 I concentration curve

  13. The Globalisation of migration

    OpenAIRE

    Milan Mesić

    2002-01-01

    The paper demonstrates that contemporary international migration is a constitutive part of the globalisation process. After defining the concepts of globalisation and the globalisation of migration, the author discusses six key themes, linking globalisation and international migration (“global cities”, the scale of migration; diversification of migration flows; globalisation of science and education; international migration and citizenship; emigrant communities and new identities). First, in ...

  14. Multisource Least-squares Reverse Time Migration

    KAUST Repository

    Dai, Wei

    2012-01-01

    is implemented with random time-shift and random source polarity encoding functions. Numerical tests on the 2D HESS VTI data show that the multisource LSRTM algorithm suppresses migration artifacts, balances the amplitudes, improves image resolution, and reduces

  15. Migration and Remittances : Recent Developments and Outlook - Transit Migration

    OpenAIRE

    World Bank Group

    2018-01-01

    This Migration and Development Brief reports global trends in migration and remittance flows, as well as developments related to the Global Compact on Migration (GCM), and the Sustainable Development Goal (SDG) indicators for volume of remittances as percentage of gross domestic product (GDP) (SDG indicator 17.3.2), reducing remittance costs (SDG indicator 10.c.1) and recruitment costs (SD...

  16. Nuclear waste repository simulation experiments (brine migration), Asse Mine of the Federal of Germany: Quarterly brine migration data report, July-September 1984

    International Nuclear Information System (INIS)

    Coyle, A.J.; Kalia, H.N.; Eckert, J.L.

    1986-10-01

    The fifth brine migration data status report describes experiments simulating a nuclear waste repository at the 800-m (2624-ft) level of the Asse Salt Mine in the Federal Republic of Germany from May 1983 through September 1984. This report describes the test equipment, the Asse Salt Mine, and the pretest properties of the salt in the test gallery. This report also includes test data for the first 16 months of operations on brine migration rates, borehole pressure, salt temperatures, and thermomechanical behavior of the salt. Annual reports have been prepared for the years 1983 and 1984, describing the test activities on a yearly basis (Rothfuchs et al., 1984, 1986). The duration of the experiments will be approximately 2 years, ending in December 1985. 2 refs., 118 figs., 91 tabs

  17. Nanoparticles migration in fractured rocks and affects on contaminant migration

    Science.gov (United States)

    Missana, Tiziana; Garcia-Gutierrez, Miguel; Alonso, Ursula

    2014-05-01

    In previous studies, the transport behavior of artificial (gold and latex) and natural (smectite clay) colloids, within a planar fracture in crystalline rock, was analyzed. In order to better understand the effects of colloid size, shape and surface charge on nanoparticle migration and especially on filtration processes on natural rock surfaces, different clay colloids and oxide nanoparticles were selected and their transport studied as a function of the residence time. In all the cases, (a fraction of) the nanoparticles travelled in the fracture as fast as or faster than water (with a retardation factor, Rf ≤ 1) and the observed Rf, was related to the Taylor dispersion coefficient, accounting for colloid size, water velocity and fracture width. However, under most of the cases, in contrast to the behavior of a conservative tracer, colloids recovery was much lower than 100 %. Differences in recovery between different nanoparticles, under similar residence times, were analyzed. In order to evaluate the possible consequences, on contaminant migration, of the presence of nanoparticles in the system, transport tests were carried out with both colloids and sorbing radionuclides. The overall capacity for colloids of enhancing radionuclide migration in crystalline rock fractures is discussed. Acknowledgments: The research leading to these results received funding from EU FP7/2007-2011 grant agreement Nº 295487 (BELBAR, Bentonite Erosion: effects on the Long term performance of the engineered Barrier and Radionuclide Transport) and by the Spanish Government under the project NANOBAG (CTM2011-2797).

  18. Simulating migrated and inverted seismic data for enhanced reservoir characterization

    NARCIS (Netherlands)

    Toxopeus, G.

    2006-01-01

    An optimal use of shared-earth modeling is hampered by the fact that simulating a migrated image that can be compared directly to the real migrated image is time-consuming. The key to enable iterative testing of different geological scenarios is to filter a shared-earth model by a spatial resolution

  19. Domal salt brine migration experiments at Avery Island, Louisiana

    International Nuclear Information System (INIS)

    Krause, W.B.; Gnirk, P.F.

    1981-01-01

    Three in-situ brine migration experiments were performed in domal salt in the Avery Island mine located in southwestern Louisiana. The primary measurements included temperature, moisture collection, and pre- and post-test permeability at the experimental sites. Experimental data are discussed and compared with calculations based on the single-crystal brine migration theory. Comparisons indicate reasonable agreement between experiment and theory

  20. Accelerated physical modelling of radioactive waste migration in soil

    International Nuclear Information System (INIS)

    Zimmie, T.F.; De, A.; Mahmud, M.B.

    1994-01-01

    A 100 g-tonne geotechnical centrifuge was used to study the long-term migration of a contaminant and radioactive tracer through a saturated soil medium. The use of the centrifuge simulates the acceleration of travel time in the prototype, which is N times larger than the model, by N 2 , where N is the desired g level. For a 5 h run at 60 g, the test modelled a migration time of about 2 years for a prototype 60 times larger than the small-scale model tested. Iodine 131, used as the tracer, was injected onto the surface of the soil, and was allowed to migrate with a constant head of water through the saturated soil. End window Geiger-Mueller (G-M) tubes were used to measure the count rate of the radioactive tracer flowing through the soil. The time from the peak response of one G-M tube to the other denotes the travel time between the two points in the flow domain. The results obtained using the radioactive tracer are in good agreement with the test performed on the same model setup using potassium permanganate as tracer and with numerical flow net modelling. Radioactive tracers can be useful in the study of nonradioactive contaminants as well, offering a nonintrusive (nondestructive) method of measuring contaminant migration. (author). 18 refs., 1 tab., 7 figs

  1. Human migration, protected areas, and conservation outreach in Tanzania.

    Science.gov (United States)

    Salerno, Jonathan D; Borgerhoff Mulder, Monique; Kefauver, Shawn C

    2014-06-01

    A recent discussion debates the extent of human in-migration around protected areas (PAs) in the tropics. One proposed argument is that rural migrants move to bordering areas to access conservation outreach benefits. A counter proposal maintains that PAs have largely negative effects on local populations and that outreach initiatives even if successful present insufficient benefits to drive in-migration. Using data from Tanzania, we examined merits of statistical tests and spatial methods used previously to evaluate migration near PAs and applied hierarchical modeling with appropriate controls for demographic and geographic factors to advance the debate. Areas bordering national parks in Tanzania did not have elevated rates of in-migration. Low baseline population density and high vegetation productivity with low interannual variation rather than conservation outreach explained observed migration patterns. More generally we argue that to produce results of conservation policy significance, analyses must be conducted at appropriate scales, and we caution against use of demographic data without appropriate controls when drawing conclusions about migration dynamics. © 2014 Society for Conservation Biology.

  2. Multiples least-squares reverse time migration

    KAUST Repository

    Zhang, Dongliang

    2013-01-01

    To enhance the image quality, we propose multiples least-squares reverse time migration (MLSRTM) that transforms each hydrophone into a virtual point source with a time history equal to that of the recorded data. Since each recorded trace is treated as a virtual source, knowledge of the source wavelet is not required. Numerical tests on synthetic data for the Sigsbee2B model and field data from Gulf of Mexico show that MLSRTM can improve the image quality by removing artifacts, balancing amplitudes, and suppressing crosstalk compared to standard migration of the free-surface multiples. The potential liability of this method is that multiples require several roundtrips between the reflector and the free surface, so that high frequencies in the multiples are attenuated compared to the primary reflections. This can lead to lower resolution in the migration image compared to that computed from primaries.

  3. Migration Performance for Legacy Data Access

    Directory of Open Access Journals (Sweden)

    Kam Woods

    2008-12-01

    Full Text Available We present performance data relating to the use of migration in a system we are creating to provide web access to heterogeneous document collections in legacy formats. Our goal is to enable sustained access to collections such as these when faced with increasing obsolescence of the necessary supporting applications and operating systems. Our system allows searching and browsing of the original files within their original contexts utilizing binary images of the original media. The system uses static and dynamic file migration to enhance collection browsing, and emulation to support both the use of legacy programs to access data and long-term preservation of the migration software. While we provide an overview of the architectural issues in building such a system, the focus of this paper is an in-depth analysis of file migration using data gathered from testing our software on 1,885 CD-ROMs and DVDs. These media are among the thousands of collections of social and scientific data distributed by the United States Government Printing Office (GPO on legacy media (CD-ROM, DVD, floppy disk under the Federal Depository Library Program (FDLP over the past 20 years.

  4. Evaluation of gas migration characteristics of compacted bentonite considering in-situ conditions of disposal facility

    International Nuclear Information System (INIS)

    Tanaka, Yukihisa; Hironaga, Michihiko

    2012-01-01

    In the current concept of repository for radioactive waste disposal, compacted bentonite will be used as an engineered barrier mainly for inhibiting migration of radioactive nuclides. Hydrogen gas can be generated inside the engineered barrier by anaerobic corrosion of metals used for containers, etc. If the gas generation rate exceeds the diffusion rate of gas molecules inside of the engineered barrier, gas will accumulate in the void space inside of the engineered barrier until its pressure becomes large enough for it to enter the bentonite as a discrete gaseous phase. It is expected to be not easy for gas to entering into the bentonite as a discrete gaseous phase because the pore of compacted bentonite is so minute. Therefore it is necessary to investigate the effect of gas pressure generation and gas migration on the engineered barrier, peripheral facilities and ground. CRIEPI already proposed an analytical method for simulating gas migration through the compacted bentonite using the model of two phase flow through deformable porous media. Though validity of the analytical code of CRIEPI was examined by comparing existing gas migration test results with the calculated results, further validation is needed because in situ conditions, such as stress conditions and boundary condition, are different from conventional laboratory gas migration tent. In this study, gas migration tests whose initial axial stress is larger than initial radial stress and gas migration tests whose gas inlet is small. Simulation of the test results is also conducted. Comparing the test results with the calculated results, it is revealed that the analytical code of CRIEPI can simulate gas migration behavior through compacted bentonite with accuracy. (author)

  5. Simulating the Oceanic Migration of Silver Japanese Eels.

    Directory of Open Access Journals (Sweden)

    Yu-Lin Chang

    Full Text Available The oceanic migration of silver Japanese eels starts from their continental growth habitats in East Asia and ends at the spawning area near the West Mariana Ridge seamount chain. However, the actual migration routes remain unknown. In this study, we examined the possible oceanic migration routes and strategies of silver Japanese eels using a particle tracking method in which virtual eels (v-eels were programmed to move vertically and horizontally in an ocean circulation model (Japan Coastal Ocean Predictability Experiment 2, JCOPE2. Four horizontal swimming strategies were tested: random heading, true navigation (readjusted heading, orientation toward the spawning area (fixed heading, and swimming against the Kuroshio. We found that all strategies, except random swimming, allowed v-eels swimming at 0.65 m s-1 to reach the spawning area within eight months after their departure from the south coast of Japan (end of the spawning season. The estimated minimum swimming speed required to reach the area spawning within eight months was 0.1 m s-1 for true navigation, 0.12 m s-1 for constant compass heading, and 0.35 m s-1 for swimming against the Kuroshio. The lowest swimming speed estimated from tracked Japanese eels at sea was 0.03 m.s-1, which would not allow them to reach the spawning area within eight months, through any of the tested orientation strategies. Our numerical experiments also showed that ocean circulation significantly affected the migration of Japanese v-eels. A strong Kuroshio could advect v-eels further eastward. In addition, western Pacific ocean currents accelerated the migration of navigating v-eels. The migration duration was shortened in years with a stronger southward flow, contributed by a stronger recirculation south of Japan, an enhanced subtropical gyre, or a higher southward Kuroshio velocity.

  6. Simulating the Oceanic Migration of Silver Japanese Eels.

    Science.gov (United States)

    Chang, Yu-Lin; Miyazawa, Yasumasa; Béguer-Pon, Mélanie

    2016-01-01

    The oceanic migration of silver Japanese eels starts from their continental growth habitats in East Asia and ends at the spawning area near the West Mariana Ridge seamount chain. However, the actual migration routes remain unknown. In this study, we examined the possible oceanic migration routes and strategies of silver Japanese eels using a particle tracking method in which virtual eels (v-eels) were programmed to move vertically and horizontally in an ocean circulation model (Japan Coastal Ocean Predictability Experiment 2, JCOPE2). Four horizontal swimming strategies were tested: random heading, true navigation (readjusted heading), orientation toward the spawning area (fixed heading), and swimming against the Kuroshio. We found that all strategies, except random swimming, allowed v-eels swimming at 0.65 m s-1 to reach the spawning area within eight months after their departure from the south coast of Japan (end of the spawning season). The estimated minimum swimming speed required to reach the area spawning within eight months was 0.1 m s-1 for true navigation, 0.12 m s-1 for constant compass heading, and 0.35 m s-1 for swimming against the Kuroshio. The lowest swimming speed estimated from tracked Japanese eels at sea was 0.03 m.s-1, which would not allow them to reach the spawning area within eight months, through any of the tested orientation strategies. Our numerical experiments also showed that ocean circulation significantly affected the migration of Japanese v-eels. A strong Kuroshio could advect v-eels further eastward. In addition, western Pacific ocean currents accelerated the migration of navigating v-eels. The migration duration was shortened in years with a stronger southward flow, contributed by a stronger recirculation south of Japan, an enhanced subtropical gyre, or a higher southward Kuroshio velocity.

  7. Population, migration and urbanization.

    Science.gov (United States)

    1982-06-01

    Despite recent estimates that natural increase is becoming a more important component of urban growth than rural urban transfer (excess of inmigrants over outmigrants), the share of migration in the total population growth has been consistently increasing in both developed and developing countries. From a demographic perspective, the migration process involves 3 elements: an area of origin which the mover leaves and where he or she is considered an outmigrant; the destination or place of inmigration; and the period over which migration is measured. The 2 basic types of migration are internal and international. Internal migration consists of rural to urban migration, urban to urban migration, rural to rural migration, and urban to rural migration. Among these 4 types of migration various patterns or processes are followed. Migration may be direct when the migrant moves directly from the village to the city and stays there permanently. It can be circular migration, meaning that the migrant moves to the city when it is not planting season and returns to the village when he is needed on the farm. In stage migration the migrant makes a series of moves, each to a city closer to the largest or fastest growing city. Temporary migration may be 1 time or cyclical. The most dominant pattern of internal migration is rural urban. The contribution of migration to urbanization is evident. For example, the rapid urbanization and increase in urban growth from 1960-70 in the Republic of Korea can be attributed to net migration. In Asia the largest component of the population movement consists of individuals and groups moving from 1 rural location to another. Recently, because urban centers could no longer absorb the growing number of migrants from other places, there has been increased interest in the urban to rural population redistribution. This reverse migration also has come about due to slower rates of employment growth in the urban centers and improved economic opportunities

  8. Radon depth migration

    International Nuclear Information System (INIS)

    Hildebrand, S.T.; Carroll, R.J.

    1993-01-01

    A depth migration method is presented that used Radon-transformed common-source seismograms as input. It is shown that the Radon depth migration method can be extended to spatially varying velocity depth models by using asymptotic ray theory (ART) to construct wavefield continuation operators. These operators downward continue an incident receiver-array plane wave and an assumed point-source wavefield into the subsurface. The migration velocity model is constrain to have longer characteristic wavelengths than the dominant source wavelength such that the ART approximations for the continuation operators are valid. This method is used successfully to migrate two synthetic data examples: (1) a point diffractor, and (2) a dipping layer and syncline interface model. It is shown that the Radon migration method has a computational advantage over the standard Kirchhoff migration method in that fewer rays are computed in a main memory implementation

  9. Prevention of the wind migration of Semipalatinsk test site contaminated topsoil by inter-polymer complexes

    International Nuclear Information System (INIS)

    Kudaibergenov, S.E.

    2010-01-01

    Full text: It is well known that Semipalatinsk Test Site has been contaminated by radionuclides mainly as a result of atmospheric, aboveground and underground intensive nuclear tests during more than 40 years. Survey of residual radioactivity in the soil at ten Semipalatinsk Test Site areas showed that a great number of Plutonium-239, 240, Strontium-90 and Cesium-137 are concentrated in the depth of soil layer 0-8 cm. The residual radioactivity within the Semipalatinsk Test Site is tightly bound to the topsoil as a result of extreme heating and melting of the soils during the tests. The maximal amount of radionuclides is accumulated on the fine soil particles having 0.1-1.0 mm size. Wind erosion is responsible for suspension of contaminated soil particles in the air and further spreading of contamination far away. For instance, dust particles of diameter 0,05-0,1 mm are dropped within a couple of kilometers of the erosion site, while particles of about 0.005-0.01 mm diameter can move hundreds and thousands of kilometers. According to the results of the Institute of Radiation Safety and Ecology, Kazakhstan, in “Degelen” massive, where the intensive nuclear tests were carried out, the concentration of radionuclides in air increases for Sr-90 up to 5 times, for Pu-239,240 up to 100-250 times during the elevation of thin dust from the ground surface. In this connection agglomeration of thin dust containing radionuclides is of primary importance to protect the population from inhalation of re-suspended dust. Inter-polymer complexes are water-insoluble, moisture and gas permeable substances that form a “cobweb” on the surface of soil particles and consequently leading to formation of protective crust. Inter-polymer complexes enhance the intrusion of water into the soil, resulting in increased soil moisture to promote seed germination and plant growth. Inter-polymer complexes are also able to accumulate radionuclides via inclusion of metal ions into the Inter

  10. Calculator for the correction of the experimental specific migration for comparison with the legislative limit

    DEFF Research Database (Denmark)

    Petersen, Jens Højslev; Hoekstra, Eddo J.

    The EURL-NRL-FCM Taskforce on the Fourth Amendment of the Plastic Directive 2002/72/EC developed a calculator for the correction of the test results for comparison with the specific migration limit (SML). The calculator calculates the maximum acceptable specific migration under the given experime......The EURL-NRL-FCM Taskforce on the Fourth Amendment of the Plastic Directive 2002/72/EC developed a calculator for the correction of the test results for comparison with the specific migration limit (SML). The calculator calculates the maximum acceptable specific migration under the given...... experimental conditions in food or food stimulant and indicates whether the test result is in compliance with the legislation. This calculator includes the Fat Reduction Factor, the simulant D Reduction Factor and the factor of the difference in surface-to-volume ratio between test and real food contact....

  11. Professional exposure to ionizing radiation some hematological cytomorfological and immunological tests

    International Nuclear Information System (INIS)

    Trajkovicj, M.; Veljkovicj, D.; Barjaktarevicj, N.; Kosticj, V.; Brkicj, S.; Pendicj, B.

    1977-01-01

    The paper represents results of some hematological, cytomorphological and immunological tests for persons professionally exposed to ionizing radiations. Number of leucocytes, neutrophil granulocytes and lymphocytes do not show statistically significant differences between the exposed and control groups. An increase of binucleated lymphocytes and chromosome abberations is registered, the second being statistically significant in comparison to the control group. A small depression in cellular immunity is observed for several persons working with ionizing radiation for a longer period

  12. Theoretical foundations of international migration process studies: analysis of key migration theories development

    Directory of Open Access Journals (Sweden)

    Shymanska K.V.

    2017-03-01

    Full Text Available The need for transformation of Ukraine's migration policy based on globalized world development trends and in response to the challenges of European integration transformations causes the need of researching the theoretical and methodological basis of migration studies, and the regulations of existing theories of international migration. The bibliometric analysis of scientific publications on international migration in cites indexes found that the recent researches on these problems acquire interdisciplinary character. It necessitates the transformation of migration study approaches basing on economic, social, institutional theories and concepts synthesis. The article is devoted to the study of theoretical regulations of existing international migration theories in the context of the evolution of scientists’ views on this phenomenon. The author found that the existing theories of international migration should be divided into three categories (microeconomic, macroeconomic, globalizational that contributes to their understanding in the context of implementation possibilities in migrational public administration practice. It allows to determine the theories which should be used for Ukrainian state migration policy constructing and eliminating or reducing the external migration negative effects.

  13. Effect of relative humidity on migration of BP from paperboard into a food simulant

    DEFF Research Database (Denmark)

    Barnkob, Line Lundbæk; Petersen, Jens Højslev

    In the scientific literature it is obligatory to control and report the test time and temperature applied when testing migration but it is not current practice to either control or report the relative humidity (RH).......In the scientific literature it is obligatory to control and report the test time and temperature applied when testing migration but it is not current practice to either control or report the relative humidity (RH)....

  14. Gas migration characteristics of highly compacted bentonite ore

    International Nuclear Information System (INIS)

    Tanaka, Yukihisa; Hironaga, Michihiko

    2010-01-01

    In the current concept of repository for radioactive waste disposal, compacted bentonite will be used as an engineered barrier mainly for inhibiting migration of radioactive nuclides. Hydrogen gas can be generated inside the engineered barrier by anaerobic corrosion of metals used for containers, etc. If the gas generation rate exceeds the diffusion rate of dissolved gas inside of the engineered barrier, gas will accumulate in the void space inside of the engineered barrier until its pressure becomes large enough for it to enter the bentonite as a discrete gaseous phase. It is expected to be not easy for gas to entering into the bentonite as a discrete gaseous phase because the pore of compacted bentonite is so minute. Gas migration characteristics of highly compacted powdered bentonite are already reported by CRIEPI. In this report, gas migration characteristics of bentonite ore, which is a candidate for construction material of repository for radioactive waste, is investigated. The following conclusions are obtained through the results of the gas migration tests which are conducted in this study: 1) When the total gas pressure exceeds the initial total axial stress, the total axial stress is always equal to the total gas pressure because specimens shrink in the axial direction with causing the clearance between the end of the specimen and porous metal. By increasing the gas pressure more, gas breakthrough, which defined as a sudden and sharp increase in gas flow rate out of the specimen, occurs. Therefore gas migration mechanism of compacted bentonite ore is basically identical to that of compacted powdered bentonite. 2) Hydraulic conductivity measured after the gas breakthrough is somewhat smaller than that measured before the gas migration test. This fact means that it might be possible to neglect decline of the function of bentonite as engineered barrier caused by the gas breakthrough. These characteristics of compacted bentonite ore are identical to those of

  15. Migration and risk: net migration in marginal ecosystems and hazardous areas

    International Nuclear Information System (INIS)

    De Sherbinin, Alex; Levy, Marc; Adamo, Susana; MacManus, Kytt; Yetman, Greg; Mara, Valentina; Razafindrazay, Liana; Aichele, Cody; Pistolesi, Linda; Goodrich, Benjamin; Srebotnjak, Tanja

    2012-01-01

    The potential for altered ecosystems and extreme weather events in the context of climate change has raised questions concerning the role that migration plays in either increasing or reducing risks to society. Using modeled data on net migration over three decades from 1970 to 2000, we identify sensitive ecosystems and regions at high risk of climate hazards that have seen high levels of net in-migration and out-migration over the time period. This paper provides a literature review on migration related to ecosystems, briefly describes the methodology used to develop the estimates of net migration, then uses those data to describe the patterns of net migration for various ecosystems and high risk regions. The study finds that negative net migration generally occurs over large areas, reflecting its largely rural character, whereas areas of positive net migration are typically smaller, reflecting its largely urban character. The countries with largest population such as China and India tend to drive global results for all the ecosystems found in those countries. Results suggest that from 1970 to 2000, migrants in developing countries have tended to move out of marginal dryland and mountain ecosystems and out of drought-prone areas, and have moved towards coastal ecosystems and areas that are prone to floods and cyclones. For North America results are reversed for dryland and mountain ecosystems, which saw large net influxes of population in the period of record. Uncertainties and potential sources of error in these estimates are addressed. (letter)

  16. Toward predictive scenarios of planetary migration

    International Nuclear Information System (INIS)

    Baruteau, Clement

    2008-01-01

    The recent detection of extra-solar planets has provided an exciting opportunity to test our theories of planet formation and evolution. An impressive result is the significant proportion of giant planets located much closer to their star than Mercury is from our own Sun. These planets should have formed further out in the protoplanetary disc, thus one needs to explain how they could move closer to their host star. Remarkably enough, such an explanation was proposed well before the discovery of the first exo-planet. It considered the interaction between a planet and the protoplanetary disc, which leads to a decrease of the planet's semi-major axis. This is known as planetary migration. Many studies have shown that the migration timescale of low-mass planets is much shorter than the lifetime of the disc. All planets should therefore have migrated to the vicinity of their host star. This is at least in contradiction with the locations of the planets in our Solar System. In order to elaborate predictive scenarios of planet formation and evolution, it is of primary interest to refine our understanding of disc-planet interactions. The inclusion of the disc self-gravity is an illustration of this. With analytical and numerical arguments, I show that discarding the self-gravity leads to a significant overestimate of the differential Lindblad torque for migrating low-mass planets. Another aspect explored in this thesis is the impact of the gas thermodynamics on migration. I show that the thermodynamic evolution of the disc induces an additional contribution to the corotation torque, which may dramatically slow down or even reverse the migration of low-mass planets. (author) [fr

  17. Neuronal Migration and Neuronal Migration Disorder in Cerebral Cortex

    OpenAIRE

    SUN, Xue-Zhi; TAKAHASHI, Sentaro; GUI, Chun; ZHANG, Rui; KOGA, Kazuo; NOUYE, Minoru; MURATA, Yoshiharu

    2002-01-01

    Neuronal cell migration is one of the most significant features during cortical development. After final mitosis, neurons migrate from the ventricular zone into the cortical plate, and then establish neuronal lamina and settle onto the outermost layer, forming an "inside-out" gradient of maturation. Neuronal migration is guided by radial glial fibers and also needs proper receptors, ligands, and other unknown extracellular factors, requests local signaling (e.g. some emitted by the Cajal-Retz...

  18. Japanese Migration and the Americas: An Introduction to the Study of Migration.

    Science.gov (United States)

    Mukai, Gary; Brunette, Rachel

    This curriculum module introduces students to the study of migration, including a brief overview of some categories of migration and reasons why people migrate. As a case study, the module uses the Japanese migration experience in the United States, Peru, Brazil, Canada, Mexico, Argentina, Bolivia, and Paraguay. The module introduces students to…

  19. [Internal migration studies].

    Science.gov (United States)

    Stpiczynski, T

    1986-10-01

    Recent research on internal migration in Poland is reviewed. The basic sources of data, consisting of censuses or surveys, are first described. The author discusses the relationship between migration studies and other sectors of the national economy, and particularly the relationship between migration and income.

  20. Civil migration and risk assessment methodology

    International Nuclear Information System (INIS)

    Onishi, Y.; Brown, S.M.; Olsen, A.R.; Parkhurst, M.A.

    1981-01-01

    To provide a scientific basis for risk assessment and decision making, the Chemical Migration and Risk Assessment (CMRA) Methodology was developed to simulate overland and instream toxic containment migration and fate, and to predict the probability of acute and chronic impacts on aquatic biota. The simulation results indicated that the time between the pesticide application and the subsequent runoff producing event was the most important factor determining the amount of the alachlor. The study also revealed that sediment transport has important effects on contaminant migration when sediment concentrations in receiving streams are high or contaminants are highly susceptible to adsorption by sediment. Although the capabilities of the CMRA methodology were only partially tested in this study, the results demonstrate that methodology can be used as a scientific decision-making tool for toxic chemical regulations, a research tool to evaluate the relative significance of various transport and degradation phenomena, as well as a tool to examine the effectiveness of toxic chemical control practice

  1. The Last Adventure: Retirement Migration, Climate and "Amenities"

    Directory of Open Access Journals (Sweden)

    Saša Božić

    2001-12-01

    concept is "tested" in other scales. One is e.g. the force − choice continuum considering the fact that in many cases frail health, housing and daily life costs play an important role in the decision making of the retirement migrants. Another one is the production − consumption "continuum". In both cases variations stretch the concept along the scale, proving that the retirement migration cannot be treated as a clearly bounded concept. Health, climate, amenities and other factors interfere whenever an explanation is expected to emerge from the retirement migration concept. Finally, the author admits that other concepts are not completely coherent as well, they are, however, more firmly bounded. An alternative solution would be to concentrate on characteristics that are shared by all retirement migrants: retirement (as a social position, the last phase in a (post-modem biography and common Mediterranean destinations. He suggests that researchers should focus on the actors and their endeavours to fulfil their personal utopian goals and that such a proceeding would probably give good results at this stage of the retirement migration research.

  2. Further investigations on the influence of ultraviolet irradiation on blood corpuscles hemoglobin content and differential leucocyte count in the chicken

    International Nuclear Information System (INIS)

    Bolukbasi, F.

    1978-01-01

    The influence of ultraviolet irradiation, applied for one hour, with a relatively high enerqy output of 95.5x10 3 erg. cm -2 . sn -1 , on some biological parameters of chicken's blood was determined. At the 24th hour after irradiation erythrocyte count, hemoglobin content and percentages of lymphocytes, monocytes, eosinophils and basophils were decreased, but total leucocyte, thrombocyte counts and percentage of pseudoeosinophils were increased, significantly (P< 0,01). No significant changes were obtained in all parameters, at the 24th hour after a second irradiation. There were also found no differences between the values obtained at 24th hour after the second, and at 48th hour after the single irradiation, but all these values had a tendency taward the initial determinations

  3. A review of a field study of radionuclide migration from an underground nuclear explosion at the Nevada Test Site

    International Nuclear Information System (INIS)

    Hoffman, D.C.; Daniels, W.R.; Wolfsberg, K.; Thompson, J.L.; Rundberg, R.S.; Fraser, S.L.; Daniels, K.S.

    1984-01-01

    Results from a long-term (9 year) field study of the distribution of radionuclides around an underground nuclear explosion cavity at the Nevada Test Site are reviewed. The goals of this Radionuclide Migration project are to examine the rates of migration underground in various media and to determine the potential for movement, both on and off the Nevada Test Site, of radioactivity from such explosions, with particular interest in possible contamination of water supplies. Initial studies were undertaken near the site of the low-yield test Cambric, which was detonated 73 m beneath the water table in tuffaceous alluvium. Solid samples were obtained from just below ground surface to 50 m below the detonation point, and water was sampled from five different regions in the vicinity of the explosion. Ten years after the test, most of the radioactivity was found to be retained in the fused debris in the cavity region and no activity above background was found 50 m below. Only tritium and 90 Sr were present in water in the cavity at levels greater than recommended concentration guides for water in uncontrolled areas. A satellite well is being used to remove water 91 m from the detonation point. During seven years (7x10 6 m 3 ) of pumping, tritium, 85 Kr, 36 Cl and 129 I have been detected in the water. Approximately 40% of the total tritium from the cavity region has been removed by pumping at the satellite well, and the maximum in the tritium concentration is clearly defined. Use of sensitive analytical techniques has permitted measurement of the very low concentrations of 36 Cl and 129 I present in the water. The 36 Cl peak precedes the tritiated water, possibly as a result of anion exclusion. Additional analyses are in progress to better define the shape of the 129 I concentration curve. (author)

  4. Reinventing US Internal Migration Studies in the Age of International Migration.

    Science.gov (United States)

    Ellis, Mark

    2012-03-01

    I argue that researchers have sidelined attention to issues raised by US internal migration as they shifted focus to the questions posed by the post-1960s rise in US immigration. In this paper, I offer some reasons about why immigration has garnered more attention and why there needs to be greater consideration of US internal migration and its significant and myriad social, economic, political, and cultural impacts. I offer three ideas for motivating more research into US internal geographic mobility that would foreground its empirical and conceptual connections to international migration. First, there should be more work on linked migration systems investigating the connections between internal and international flows. Second, the questions asked about immigrant social, cultural, and economic impacts and adaptations in host societies should also be asked about internal migrants. Third, and more generally, migration researchers should jettison the assumption that the national scale is the pre-eminent delimiter of migration types and processes. Some groups can move easily across borders; others are constrained in their moves within countries. These subnational scales and constraints will become more visible if migration research decentres the national from its theory and empirics.

  5. MANAGING MIGRATION: TURKISH PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    İhsan GÜLAY

    2018-04-01

    Full Text Available Conducting migration studies is of vital importance to Turkey, a country which has been experiencing migration throughout history due to its “open doors policy”. The objective of this study is to evaluate the strategic management of migration in Turkey in order to deal with the issue of migration. The main focus of the study is Syrian migrants who sought refuge in Turkey due to the civil war that broke out in their country in April 2011. This study demonstrates the policies and processes followed by Turkey for Syrian migration flow in terms of the social acceptance and harmonisation of the migrants within a democratic environment. The study addresses some statistical facts and issues related to Syrian migration as it has become an integral part of daily life in Turkey. The study also reviews how human rights are protected in the migration process. The study will provide insights for developing sound strategic management policies for the migration issue.

  6. Migration chemistry

    International Nuclear Information System (INIS)

    Carlsen, L.

    1992-05-01

    Migration chemistry, the influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour of pollutants in the environment, is an interplay between the actual natur of the pollutant and the characteristics of the environment, such as pH, redox conditions and organic matter content. The wide selection of possible pollutants in combination with varying geological media, as well as the operation of different chemical -, biochemical - and physico-chemical reactions compleactes the prediction of the influence of these processes on the mobility of pollutants. The report summarizes a wide range of potential pollutants in the terrestrial environment as well as a variety of chemical -, biochemical - and physico-chemical reactions, which can be expected to influence the migration behaviour, comprising diffusion, dispersion, convection, sorption/desorption, precipitation/dissolution, transformations/degradations, biochemical reactions and complex formation. The latter comprises the complexation of metal ions as well as non-polar organics to naturally occurring organic macromolecules. The influence of the single types of processes on the migration process is elucidated based on theoretical studies. The influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour is unambiguous, as the processes apparently control the transport of pollutants in the terrestrial environment. As the simple, conventional K D concept breaks down, it is suggested that the migration process should be described in terms of the alternative concepts chemical dispersion, average-elution-time and effective retention. (AB) (134 refs.)

  7. Mathematical modelling of migration: A suitable tool for the enforcement authorities?

    DEFF Research Database (Denmark)

    Petersen, Jens Højslev; Trier, Xenia Thorsager; Fabech, B.

    2005-01-01

    possibilities of implementing migration-modelling software as a tool in official food control and possibly in improving the own-check programmes of Danish plastic-converting plants. Food inspectors from nine regional food control centres initially attended a training course in the use of a commercial modelling...... reason was a lack of information from those in the raw material supply chain who considered their products protected by commercial confidentiality. In general, the food inspectors were in favour of using migration modelling for future control visits.......A few years ago, it became accepted that the plastics industry could use migration modelling for compliance testing. When a calculation confirms that the migration of a compound from a plastic material or article is below the specific migration limit, this is considered sufficient documentation...

  8. Effects of topical vitamin E on corneal superoxide dismutase, glutathione peroxidase activities and polymorphonuclear leucocyte infiltration after photorefractive keratectomy.

    Science.gov (United States)

    Bilgihan, Ayse; Bilgihan, Kamil; Yis, Ozgür; Sezer, Cem; Akyol, Gülen; Hasanreisoglu, Berati

    2003-04-01

    Photorefractive keratectomy (PRK) induces free radical formation and polymorphonuclear (PMN) cell infiltration in the cornea. Vitamin E is a free radical scavenger and protects the cells from reactive oxygen species. We investigated the effects of topical vitamin E on corneal PMN cell infiltration and corneal antioxidant enzyme activities after PRK. We studied four groups, each consisting of seven eyes. Group 1 were control eyes. In group 2 the corneal epithelium was removed by a blunt spatula (epithelial scrape). In group 3, corneal photoablation (59 micro m, 5 dioptres) was performed after epithelial removal (traditional PRK). In group 4 we tested the effects of topical Vitamin E after traditional PRK. Corneal tissues were removed and studied with enzymatic analysis (measurement of corneal superoxide dismutase and glutathione peroxidase activities) and histologically. Stromal PMN leucocyte counts were significantly higher after mechanical epithelial removal and traditional PRK (p < 0.05). Corneal superoxide dismutase and glutathione peroxidase activities decreased significantly after mechanical epithelial removal and traditional PRK (p < 0.05). In group 4, treated with vitamin E, corneal superoxide dismutase activity did not differ significantly from that in the medically non-treated groups, nor did corneal PMN cell infiltration after traditional PRK. The reduction of corneal glutathione peroxidase activity after PRK was reduced significantly after topical vitamin E treatment. Topical vitamin E treatment may be useful for reducing the harmful effects of reactive oxygen radical after epithelial scraping and PRK in that it increases corneal glutathione peroxidase activity.

  9. Testing-ground investigations of radionuclide migration in temporary area for radioactive waste localization << Ryzhy Les >>.; Poligonnye issledovaniya migratsii radionuklidov na uchastke punkta vremennoj lokalizatsii radioaktivnykh otkhodov << Ryzhij les >>.

    Energy Technology Data Exchange (ETDEWEB)

    Dzhepo, S P; Skal` skij, A S; Bugaj, D A; Gudzenko, V V; Mogil` nyj, S A; Proskura, N I [AN Ukrainskoj SSR, Kiev (Ukraine). Inst. Geologicheskikh Nauk; [Admyinyistratsyiya zoni vyidchuzhennya, Chernobil` (Ukraine)

    1994-12-31

    Experimental investigations carried out on testing grounds have permitted studying hydrogeological and geochemical conditions, contamination levels of ground waters and mechanisms of radionuclide migration in the areas of radioactive waste burial in sector 2.1 of temporary area for radioactive waste localization << Ryzhy Les >>. Distribution coefficients for {sup 137} Cs and {sup 90} Sr as well as chemical forms of sorbed radionuclides have been determined under in situ conditions. Lateral rates of radionuclide migration in ground waters are estimated.

  10. The Exoplant Migration Timescale from K2 Young Clusters

    Science.gov (United States)

    Rizzuto, Aaron C.; Mann, Andrew; Kraus, Adam L.; Ireland, Michael

    2017-01-01

    Planetary Migration models for close-in exoplanets(a operate on timescales of ~100’s of Myr to ~1Gyr, a lengthier process than disk migration. It is unclear which of these is the dominating mechanism.The K2 mission has measured planet formation timescales and migration pathways by sampling groups of stars at key pre-main-sequence ages: Over the past 10 campaigns, multiple groups of young stars have been observed by K2, ranging from the 10 Myr Upper Scorpius OB association, through the ˜120 Myr Pleiades, the ˜600-800 Myr Hyades and Praesepe moving groups, to the original Kepler Field. The frequency, orbital and compositional properties of the exoplanet population in these samples of different age, with careful treatment of detection completeness, will be sufficient to address the question of exoplanet migration as their host stars are settling onto the main sequence.We will present the initial results of a program to directly address the question of planet migration with a uniform injection-recovery tests on a new K2 detrending pipeline that is optimized for the particular case of young, rotationally variable stars in K2 to robustly measure the detectability of planets of differing size and orbit. Initial results point towards a migration timescale of 200-700 Myr, which is consistent with the slower planet-planet scattering or Kozai migration models.

  11. Interregional income differentials and migration: their interrelationships.

    Science.gov (United States)

    Tabuchi, T

    1988-02-01

    "The major objective of this paper is to demonstrate that interregional income differential is exogenous to interregional net migration, but not conversely. Utilizing Japanese prefectural-based data for 1954-82, we conduct the following three kinds of analyses to confirm this statement. Firstly, a simple comparison of the crests of interregional time-series plots was made to see which occurred first. Secondly, Sims', 1972, test of causality was done to investigate causation between urban/rural income differential and net migration. Finally, per capita income and population share were examined by two-dimensional phase diagram for nine regions." (SUMMARY IN FRE AND GER) excerpt

  12. The possibilities of least-squares migration of internally scattered seismic energy

    KAUST Repository

    Aldawood, Ali

    2015-05-26

    Approximate images of the earth’s subsurface structures are usually obtained by migrating surface seismic data. Least-squares migration, under the single-scattering assumption, is used as an iterative linearized inversion scheme to suppress migration artifacts, deconvolve the source signature, mitigate the acquisition fingerprint, and enhance the spatial resolution of migrated images. The problem with least-squares migration of primaries, however, is that it may not be able to enhance events that are mainly illuminated by internal multiples, such as vertical and nearly vertical faults or salt flanks. To alleviate this problem, we adopted a linearized inversion framework to migrate internally scattered energy. We apply the least-squares migration of first-order internal multiples to image subsurface vertical fault planes. Tests on synthetic data demonstrated the ability of the proposed method to resolve vertical fault planes, which are poorly illuminated by the least-squares migration of primaries only. The proposed scheme is robust in the presence of white Gaussian observational noise and in the case of imaging the fault planes using inaccurate migration velocities. Our results suggested that the proposed least-squares imaging, under the double-scattering assumption, still retrieved the vertical fault planes when imaging the scattered data despite a slight defocusing of these events due to the presence of noise or velocity errors.

  13. The possibilities of least-squares migration of internally scattered seismic energy

    KAUST Repository

    Aldawood, Ali; Hoteit, Ibrahim; Zuberi, Mohammad; Turkiyyah, George; Alkhalifah, Tariq Ali

    2015-01-01

    Approximate images of the earth’s subsurface structures are usually obtained by migrating surface seismic data. Least-squares migration, under the single-scattering assumption, is used as an iterative linearized inversion scheme to suppress migration artifacts, deconvolve the source signature, mitigate the acquisition fingerprint, and enhance the spatial resolution of migrated images. The problem with least-squares migration of primaries, however, is that it may not be able to enhance events that are mainly illuminated by internal multiples, such as vertical and nearly vertical faults or salt flanks. To alleviate this problem, we adopted a linearized inversion framework to migrate internally scattered energy. We apply the least-squares migration of first-order internal multiples to image subsurface vertical fault planes. Tests on synthetic data demonstrated the ability of the proposed method to resolve vertical fault planes, which are poorly illuminated by the least-squares migration of primaries only. The proposed scheme is robust in the presence of white Gaussian observational noise and in the case of imaging the fault planes using inaccurate migration velocities. Our results suggested that the proposed least-squares imaging, under the double-scattering assumption, still retrieved the vertical fault planes when imaging the scattered data despite a slight defocusing of these events due to the presence of noise or velocity errors.

  14. Cytokine release from human peripheral blood leucocytes incubated with endotoxin with and without prior infection with influenza virus

    DEFF Research Database (Denmark)

    Banner, Jytte; Smith, H; Sweet, C

    1993-01-01

    Previous work with a neonatal ferret model for human SIDS had indicated that inflammation caused by a combination of influenza virus and bacterial endotoxin may be a cause of human SIDS. To determine whether cytokines may be involved in this inflammatory response, levels of interleukin (IL)-1 beta......, IL-6 and tumour necrosis factor (TNF)-alpha were examined, using ELISA assays, in culture supernatants of human peripheral blood leucocytes infected with influenza virus and subsequently incubated with endotoxin. Levels of TNF-alpha were increased compared to cells incubated with virus or endotoxin...... alone. Levels of IL-1 beta were also increased whereas levels of IL-6 were generally not enhanced. Cytokines appeared within 1-2 h of stimulation with virus or endotoxin and increased subsequently to reach maximum titres between 16 and 20 h post treatment. While levels of cytokine were much lower when...

  15. Nitric oxide production by nurse shark (Ginglymostoma cirratum) and clearnose skate (Raja eglanteria) peripheral blood leucocytes.

    Science.gov (United States)

    Walsh, Cathy J; Toranto, Jason D; Gilliland, C Taylor; Noyes, David R; Bodine, Ashby B; Luer, Carl A

    2006-01-01

    Reactive nitrogen intermediates, such as nitric oxide (NO), are important immunomodulators in vertebrate immune systems, but have yet to be identified as mediators of host defence in any member of class Chondrichthyes, the cartilaginous fishes. In the present study, production of NO by nurse shark (Ginglymostoma cirratum) peripheral blood leucocytes (PBL) stimulated with bacterial cell wall lipopolysaccharide (LPS) was investigated. PBL were cultured for 24 to 96 h following stimulation with LPS at concentrations ranging from 0 to 25 microg ml(-1), in both serum-supplemented and serum-free culture conditions. Production of NO was measured indirectly using the Griess reaction, with maximal NO production occurring after 72 h using 10% FBS and 10 microg LPS ml(-1). Application of these culture conditions to PBL from another cartilaginous fish (clearnose skate, Raja eglanteria) resulted in a similar NO response. Addition of a specific inhibitor of inducible nitric oxide synthase (iNOS), L-N(6)-(1-iminoethyl)lysine (L-NIL), resulted in a significant decrease in the production of NO by PBL from both species.

  16. Countering inbreeding with migration 1. Migration from unrelated ...

    African Journals Online (AJOL)

    Ret:ieved 6 Octoher 1991; ut:cepted I8 Mur- 1995. The eff'ect of migration on inbreeding is moclelled fbr small populations with immigrants from a large unrelated population. Different migration rates and numbers fbr the two sexes are assumed, and a general recursion equation for inbreeding progress derived, which can ...

  17. The Globalisation of migration

    Directory of Open Access Journals (Sweden)

    Milan Mesić

    2002-04-01

    Full Text Available The paper demonstrates that contemporary international migration is a constitutive part of the globalisation process. After defining the concepts of globalisation and the globalisation of migration, the author discusses six key themes, linking globalisation and international migration (“global cities”, the scale of migration; diversification of migration flows; globalisation of science and education; international migration and citizenship; emigrant communities and new identities. First, in accordance with Saskia Sassen’s analysis, the author rejects the wide-spread notion that unqualified migrants have lost an (important role in »global cities«, i.e. in the centres of the new (global economy. Namely, the post-modern service sector cannot function without the support of a wide range of auxiliary unqualified workers. Second, a critical comparison with traditional overseas mass migration to the USA at the turn of the 19th and 20th centuries indicates that present international migration is, perhaps, less extensive – however it is important to take into consideration various limitations that previously did not exist, and thus the present migration potential is in really greater. Third, globalisation is more evident in a diversification of the forms of migration: the source area of migrants to the New World and Europe has expanded to include new regions in the world; new immigration areas have arisen (the Middle East, new industrial countries of the Far East, South Europe; intra-regional migration has intensified. Forth, globalisation is linked to an increased migration of experts and the pessimistic notion of a brain drain has been replaced by the optimistic idea of a brain gain. Fifth, contemporary international migration has been associated with a crisis of the national model of citizenship. Sixth, the interlinking of (migrant cultural communities regardless of distance and the physical proximity of cultural centres (the

  18. Challenging issues in the study of fiscally-induced migration.

    Science.gov (United States)

    Winer, S L

    1986-01-01

    This paper reviews Shaw's book, INTERMETROPOLITAN MIGRATION IN CANADA, which provides new evidence concerning the link between fiscal structure and internal migration. Shaw bases his work on a valuable new migration series he has put together from census data: intermetropolitan flows from 1956-1981. The existence of censua data at 5-year intervals permits Shaw enough data to estimate migration equations separately for the periods before and after 1971. A comparison of the role of fiscal variables before and after 1971 is interesting because unemployment insurance, equalization payments, and provincial natural resource revenues probably became more important in determining regional differences in incomes after 1971 than in the 20 years prior to that. Shaw suspects that migration behavior has become less sensitive to traditional market variables such as wage differentials and more sensitive to other factors, including quality of life indicators since 1950. The author thinks that Shaw's conclusion cannot rest comfortably on estimating equations that omit fiscal variables. The overall role of wage differentials in determining observed migration patterns is the product of the coefficient on wage variables and the actual evolution of wages over the estimation period. Another problem with the methodology used to contrast pre- and post-1971 migration equations is the apparent neglect of statistical testing for shifts in coefficients on the traditional economic variables and for shifts in the coefficients on the fiscal variables. The strongest of the useful results from the study concern the role of unemployment insurance. The evidence that these have an influence on internal migration is now compelling. Shaw's book adds substantial weight to the view that variation in fiscal structure plays a significant role in determining internal migration patterns.

  19. Pathological analysis, detection of antigens, FasL expression analysis and leucocytes survival analysis in tilapia (Oreochromis niloticus) after infection with green fluorescent protein labeled Streptococcus agalactiae.

    Science.gov (United States)

    Wang, Jingyuan; Wu, Jinying; Yi, Liyuan; Hou, Zengxin; Li, Wensheng

    2017-03-01

    The pathogenesis of Streptococcus agalactiae infection in tilapia has not been fully described. To understand this, we investigated the clinic-pathological features of acute experimental septicemia in tilapia (Oreochromis niloticus) after receiving an intra-peritoneal injection with S. agalactiae THN-1901GFP. Immunohistochemistry and sections of pathological tissues were used to estimate the level of damage in the head-kidney, liver, spleen and trunk-kidney. The expression of FasL was analyzed by western blotting in these samples based on their damage levels. Leucocytes were isolated from the head-kidney and incubated with S. agalactiae THN-1901GFP. Then, phagocytosis, programmed cell death and the expression of FasL were analyzed. The infected tissues showed varying degrees of necrosis and histolysis. The serous membrane of the intestine was dissolved by S. agalactiae THN-1901GFP. Antigens of S. agalactiae THN-1901GFP accumulated in different parts of the infected organs. In the head-kidney and spleen, the expression of FasL was up-regulated in parallel with increased tissue damage. After being incubated with S. agalactiae THN-1901GFP, the phagocytic capacity and ability were both very high and the expression of FasL remained high in leucocytes. S. agalactiae THN-1901GFP was able to survive for a long period of time after being engulfed by phagocytic cells. These findings offer insight into the pathogenesis of S. agalactiae infection in tilapia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. The role of migration-specific and migration-relevant policies in migrant decision-making in transit

    NARCIS (Netherlands)

    Kuschminder - de Guerre, Katie; Koser, Khalid

    2017-01-01

    This paper examines the role of migration-specific and migration-relevant policies in migrant decision-making factors for onwards migration or stay in Greece and Turkey. In this paper we distinguish migration-specific policies from migration-relevant policies in transit and destination countries,

  1. Wave-equation Migration Velocity Analysis Using Plane-wave Common Image Gathers

    KAUST Repository

    Guo, Bowen

    2017-06-01

    Wave-equation migration velocity analysis (WEMVA) based on subsurface-offset, angle domain or time-lag common image gathers (CIGs) requires significant computational and memory resources because it computes higher dimensional migration images in the extended image domain. To mitigate this problem, a WEMVA method using plane-wave CIGs is presented. Plane-wave CIGs reduce the computational cost and memory storage because they are directly calculated from prestack plane-wave migration, and the number of plane waves is often much smaller than the number of shots. In the case of an inaccurate migration velocity, the moveout of plane-wave CIGs is automatically picked by a semblance analysis method, which is then linked to the migration velocity update by a connective function. Numerical tests on two synthetic datasets and a field dataset validate the efficiency and effectiveness of this method.

  2. Internal migration, regional labor markets and the role of agglomeration economies

    DEFF Research Database (Denmark)

    Mitze, Timo Friedel; Schmidt, Torben Dall

    2015-01-01

    are indeed key drivers of internal migration flows in Denmark. That is, while we obtain mixed evidence with regard to the role of traditional labor and housing market variables, most of the included proxies for agglomeration economies such as the region’s population density, patent intensity, endowment......We analyze the determinants and regional implications of internal migration flows across Danish municipalities in 2006–2012. Besides assessing the role of labor market and housing market factors in driving a region’s net migration rate, we particularly focus on agglomeration factors identified...... for the role of space–time dynamic adjustment processes and simultaneity among migration and labor market variables and finally test for heterogeneity in the migration response to regional labor market disparities among low- and high-skilled migrants. Our results support the view that agglomeration economies...

  3. [The expression of periphery blood leucocyte CCR3 and CCR5 in the children with Epstein-Barr virus associated infectious mononucleosis].

    Science.gov (United States)

    Qi, Tie-xiong; Gao, Guo-hua; Liu, Shi-hua

    2010-10-01

    To explore the expression of periphery blood leucocyte CCR3 and CCR5 and to comprehend T helper cell in the Children with Epstein-Barr virus associated infectious mononucleosis. We defined the children according to the diagnosis criterion through Paul-Bunnell test inspecting the children's periphery blood unusual lymphocyte and detecting their anti-EBV-CA-IgM, anti-EBV-CA-IgG and anti-EBV-NA-IgG by ELISA and counted the ratio of CCR3 + and CCR5 + cells in lymphocytes with flow cytometry. The ratio of unusual lymphocyte in IM was higher than that of the healthy control group (P < 0.05). The ratio of CCR3 + cells in IM group was higher than that of the healthy control group (P < 0.05). The ratio of CCR5 + cells in IM group was significantly lower than that of the healthy control group. CCR3 + had direct interrelation with fever continued time and the ratio of unusual lymphocyte. There was a negative interrelation between CCR5 and fever continued time (P < 0.05). Children infectious of IM expressed higher level of CCR3 + and lower level of CCR5 + and there was a tendency of Th2 polarization with over production of T helper cell divide imbalance. CCR3 + and CCR5 + may be important targets to judge the degree of seriousness of IM.

  4. SL(C) 5 migration at CERN

    International Nuclear Information System (INIS)

    Schwickerath, Ulrich; Silva, Ricardo

    2010-01-01

    Most LCG sites are currently running on SL(C)4. However, this operating system is already rather old, and it is becoming difficult to get the required hardware drivers, to get the best out of recent hardware. A possible way out is the migration to SL(C)5 based systems where possible, in combination with virtualization methods. The former is typically possible for nodes where the software to run the services is available and tested, while the latter offers a possibility to make use of the new hardware platforms whilst maintaining operating system compatibility. Since autumn 2008, CERN has offered public interactive and batch worker nodes for evaluation to the experiments. For the Grid environment, access is granted by a dedicated CEs. The status of the evaluation, feedback received from the experiments and the status of the migration will be reviewed, and the status of virtualization of services at CERN will be reported. Beyond this, the migration to a new operating system also offers an excellent opportunity to upgrade the fabric infrastructure used to manage the servers.

  5. Centrifuge modelling - migration of radionuclides from engineered trenches

    International Nuclear Information System (INIS)

    Dean, E.T.R.; Schofield, A.N.

    1991-12-01

    This report provides an overview of some centrifuge small-scale physical model tests and 1g experimental and theoretical work relating to the sub-surface migration of a model pollutant (sodium chloride) from a notional prototype surface landfill of width 25 metres and depth 3 metres cut into a 20 metre deep layer of nominally uniform soil overlying a more permeable base layer. An introduction is given to the application of geotechnical centrifuge modelling techniques to pollutant migration studies. Experiments performed at 1/100th scale using the Cambridge 10 metre diameter Geotechnical Beam Centrifuge simulating transport through silt over prototype time periods of around 35 years, are summarised. Comparisons of data with calculations using early versions of the POLLUTE and MIGRATE computer codes are presented. An experiment at 1/400th scale using the new Cambridge Geotechnical Drum Centrifuge, involving transport through clay over a prototype time period of around 1000 years, is described. Potential future uses of centrifuge modelling techniques to simulate long-term migration through more complex hydrological environments are also discussed. (author)

  6. Conservation physiology of animal migration

    Science.gov (United States)

    Lennox, Robert J.; Chapman, Jacqueline M.; Souliere, Christopher M.; Tudorache, Christian; Wikelski, Martin; Metcalfe, Julian D.; Cooke, Steven J.

    2016-01-01

    Migration is a widespread phenomenon among many taxa. This complex behaviour enables animals to exploit many temporally productive and spatially discrete habitats to accrue various fitness benefits (e.g. growth, reproduction, predator avoidance). Human activities and global environmental change represent potential threats to migrating animals (from individuals to species), and research is underway to understand mechanisms that control migration and how migration responds to modern challenges. Focusing on behavioural and physiological aspects of migration can help to provide better understanding, management and conservation of migratory populations. Here, we highlight different physiological, behavioural and biomechanical aspects of animal migration that will help us to understand how migratory animals interact with current and future anthropogenic threats. We are in the early stages of a changing planet, and our understanding of how physiology is linked to the persistence of migratory animals is still developing; therefore, we regard the following questions as being central to the conservation physiology of animal migrations. Will climate change influence the energetic costs of migration? Will shifting temperatures change the annual clocks of migrating animals? Will anthropogenic influences have an effect on orientation during migration? Will increased anthropogenic alteration of migration stopover sites/migration corridors affect the stress physiology of migrating animals? Can physiological knowledge be used to identify strategies for facilitating the movement of animals? Our synthesis reveals that given the inherent challenges of migration, additional stressors derived from altered environments (e.g. climate change, physical habitat alteration, light pollution) or interaction with human infrastructure (e.g. wind or hydrokinetic turbines, dams) or activities (e.g. fisheries) could lead to long-term changes to migratory phenotypes. However, uncertainty remains

  7. Migration of cesium-137 through sandy soil layer effect of fine silt on migration

    International Nuclear Information System (INIS)

    Ohnuki, Toshihiko; Wadachi, Yoshiki

    1983-01-01

    The migration of 137 Cs through sandy soil layer was studied with consideration of the migration of fine silt by column method. It was found that a portion of fine silt migrated through the soil layer accompanying with 137 Cs. The mathematical migration model of 137 Cs involved the migration of fine silt through such soil layer was presented. This model gave a good accordance between calculated concentration distribution curve in sandy soil layer and effluent curve and observed those. So, this model seems to be advanced one for evaluating migration of 137 Cs in sandy soil layer with silt. (author)

  8. South-South Migration and Remittances

    OpenAIRE

    Ratha, Dilip; Shaw, William

    2007-01-01

    South-South Migration and Remittances reports on preliminary results from an ongoing effort to improve data on bilateral migration stocks. It sets out some working hypotheses on the determinants and socioeconomic implications of South-South migration. Contrary to popular perception that migration is mostly a South-North phenomenon, South-South migration is large. Available data from nation...

  9. Prestack depth migration

    International Nuclear Information System (INIS)

    Postma, R.W.

    1991-01-01

    Two lines form the southern North Sea, with known velocity inhomogeneities in the overburden, have been pre-stack depth migrated. The pre-stack depth migrations are compared with conventional processing, one with severe distortions and one with subtle distortions on the conventionally processed sections. The line with subtle distortions is also compared with post-stack depth migration. The results on both lines were very successful. Both have already influenced drilling decisions, and have caused a modification of structural interpretation in the respective areas. Wells have been drilled on each of the lines, and well tops confirm the results. In fact, conventional processing led to incorrect locations for the wells, both of which were dry holes. The depth migrated sections indicate the incorrect placement, and on one line reveals a much better drilling location. This paper reports that even though processing costs are high for pre-stack depth migration, appropriate use can save millions of dollars in dry-hole expense

  10. Minocycline affects human neutrophil respiratory burst and transendothelial migration.

    Science.gov (United States)

    Parenti, Astrid; Indorato, Boris; Paccosi, Sara

    2017-02-01

    This study aimed at investigating the in vitro activity of minocycline and doxycycline on human polymorphonuclear (h-PMN) cell function. h-PMNs were isolated from whole venous blood of healthy subjects; PMN oxidative burst was measured by monitoring ROS-induced oxidation of luminol and transendothelial migration was studied by measuring PMN migration through a monolayer of human umbilical vein endothelial cells. Differences between multiple groups were determined by ANOVA followed by Tukey's multiple comparison test; Student's t test for unpaired data for two groups. Minocycline (1-300 µM) concentration dependently and significantly inhibited oxidative burst of h-PMNs stimulated with 100 nM fMLP. Ten micromolar concentrations, which are superimposable to C max following a standard oral dose of minocycline, promoted a 29.8 ± 4 % inhibition of respiratory burst (P minocycline impaired PMN transendothelial migration, with maximal effect at 100 µM (42.5 ± 7 %, inhibition, n = 5, P minocycline exerted on innate immune h-PMN cell function.

  11. Household ecology and out-migration among ethnic Karen along the Thai-Myanmar border

    Directory of Open Access Journals (Sweden)

    Daniel M. Parker

    2014-04-01

    Full Text Available Background: Local migration in developing-world settings, particularly among rural populations, is an important yet understudied demographic process. Research on migration in such populations can help us test and inform anthropological and demographic theory. Furthermore, it can lead to a better understanding of modern population distributions and epidemiologic landscapes. Objective: The purpose of this study was to investigate the potential relationships between household- and individual-level factors on out-migration among Karen villagers along the Thai-Myanmar border. Methods: We used a random effects hazard model to investigate the relationship of household consumer-producer (C/P ratios, the number of household members, and an individual's sex on the odds of outmigration. We then used simulations in order to test the sensitivity of our model to our C/P ratio weighting scheme. Results: We found that the number of household members is predictive of increased out-migration. Household C/P ratios were positively associated with out-migration in children but negatively associated with out-migration in working age adults. Finally, adult males were much more likely to move out of the household than were adult females. Conclusions: While household-level factors are important with regard to out-migration, the relationships between such household-level factors and out-migration are complex and vary by the individual's age and sex. Our study offers two novel concepts to household demography and migration studies. First, this study offers a new approach to evaluating weighting schemes for C/P ratios. Second, we show that household level factors are important at units of time (two-week intervals that are not normally studied by demographers.

  12. Indonesia's migration transition.

    Science.gov (United States)

    Hugo, G

    1995-01-01

    This article describes population movements in Indonesia in the context of rapid and marked social and economic change. Foreign investment in Indonesia is increasing, and global mass media is available to many households. Agriculture is being commercialized, and structural shifts are occurring in the economy. Educational levels are increasing, and women's role and status are shifting. Population migration has increased over the decades, both short and long distance, permanent and temporary, legal and illegal, and migration to and between urban areas. This article focuses specifically on rural-to-urban migration and international migration. Population settlements are dense in the agriculturally rich inner areas of Java, Bali, and Madura. Although the rate of growth of the gross domestic product was 6.8% annually during 1969-94, the World Bank ranked Indonesia as a low-income economy in 1992 because of the large population size. Income per capita is US $670. Indonesia is becoming a large exporter of labor to the Middle East, particularly women. The predominance of women as overseas contract workers is changing women's role and status in the family and is controversial due to the cases of mistreatment. Malaysia's high economic growth rate of over 8% per year means an additional 1.3 million foreign workers and technicians are needed. During the 1980s urban growth increased at a very rapid rate. Urban growth tended to occur along corridors and major transportation routes around urban areas. It is posited that most of the urban growth is due to rural-to-urban migration. Data limitations prevent an exact determination of the extent of rural-to-urban migration. More women are estimated to be involved in movements to cities during the 1980s compared to the 1970s. Recruiters and middlemen have played an important role in rural-to-urban migration and international migration.

  13. Evaluation of gas migration characteristics of compacted bentonite and Ca-bentonite mixture

    International Nuclear Information System (INIS)

    Tanaka, Yukihisa; Hironaga, Michihiko

    2014-01-01

    In the current concept of subsurface disposal and near-surface pit disposal for low level radioactive waste, compacted bentonite and Ca-bentonite mixture will be used as an engineered barrier mainly for inhibiting migration of radioactive nuclides, respectively. Hydrogen gas can be generated inside the engineered barrier of subsurface disposal facilities mainly by anaerobic corrosion of metals used for containers, etc. Hydrogen gas can be also generated inside the engineered barrier of near-surface pit disposal facilities mainly by the chemical interaction between aluminum and the alkaline component of cement, or water. If the gas generation rate exceeds the diffusion rate of gas molecules inside of the compacted bentonite and Ca-bentonite mixture, gas will accumulate in the void space inside of the compacted bentonite and Ca-bentonite mixture until breakthrough occurs. It is expected to be not easy for gas to entering into the compacted bentonite mixture as a discrete gaseous phase because the pore of the compacted bentonite and Ca-bentonite mixture is so minute. Therefore in this study, the gas migration characteristics and the effect of gas migration on the hydraulic conductivity of the compacted bentonite and Ca-bentonite mixture are investigated by the gas migration tests. The applicability of the two phase flow model without considering deformability of the specimen is investigated. The applicability of the model of two phase flow through deformable porous media, which was originally developed by CRIEPI, is also investigated. Results of this study imply that : (1) Gas migration mechanism of the compacted bentonite and Ca-bentonite mixture is revealed through gas migration test. (2) Hydraulic conductivity measured after the large gas breakthrough is substantially the same that measured before the gas migration test. (3) Stress change, pore-water pressure change and volume change of the specimen during the gas migration test can be reproduced by the numerical

  14. Quantitative elastic migration. Applications to 3D borehole seismic surveys; Migration elastique quantitative. Applications a la sismique de puits 3D

    Energy Technology Data Exchange (ETDEWEB)

    Clochard, V.

    1998-12-02

    3D VSP imaging is nowadays a strategic requirement by petroleum companies. It is used to precise in details the geology close to the well. Because of the lack of redundancy and limited coverage in the data. this kind of technology is more restrictive than surface seismic which allows an investigation at a higher scale. Our contribution was to develop an elastic quantitative imagine (GRT migration) which can be applied to 3 components borehole dataset. The method is similar to the Kirchhoff migration using sophistical weighting of the seismic amplitudes. In reality. GRT migration uses pre-calculated Green functions (travel time. amplitude. polarization). The maps are obtained by 3D ray tracing (wavefront construction) in the velocity model. The migration algorithm works with elementary and independent tasks. which is useful to process different kind of dataset (fixed or moving geophone antenna). The study has been followed with validations using asymptotic analytical solution. The ability of reconstruction in 3D borehole survey has been tested in the Overthrust synthetic model. The application to a real circular 3D VSP shows various problems like velocity model building, anisotropy factor and the preprocessing (deconvolution. wave mode separation) which can destroy seismic amplitudes. An isotropic 3 components preprocessing of the whole dataset allows a better lateral reconstruction. The choice of a big migration aperture can help the reconstruction of strong geological dip in spite of migration smiles. Finally, the methodology can be applied to PS converted waves. (author)

  15. 3D Multi‐source Least‐squares Reverse Time Migration

    KAUST Repository

    Dai, Wei

    2010-10-17

    We present the theory and numerical results for least‐squares reverse time migration (LSRTM) of phase‐encoded supergathers, where each supergather is the superposition of phased‐encoded shots. Three type of encoding functions are used in this study: random time shift, random source polarity and random source location selected from a pre‐designed table. Numerical tests for the 3D SEG/EAGE Overthrust model show that multi‐source LSRTM can suppress migration artifacts in the migration image and remove most of the crosstalk noise from multi‐source data. Empirical results suggest that multi‐source LSRTM can provide a noticeable increase in computational efficiency compared to standard RTM, when the CSGs in a supergather are modeled and migrated together with a finite‐difference simulator. If the phase‐encoding functions are dynamically changed after each iteration of LSRTM, the best images are obtained. The potential drawback is that the final results are very sensitive to the accuracy of the starting model.

  16. Brine Migration in Heated Salt: Lessons Learned from Field Experiments

    Science.gov (United States)

    Kuhlman, K. L.; Matteo, E. N.; Mills, M.

    2017-12-01

    We summarize several interesting brine migration related phenomena hinted at in field experiments from field testing related to salt radioactive waste repositories in Germany and the US. Past heater tests in salt have shown 1) thermal-hydrological-mechanical coupling is quite strong during both heating and cooling; 2) chemical composition of brine evolves during heating, and comprises a mix of several water sources; and 3) acid gas (HCl) generation has been observed during past heater tests and may have multiple mechanisms for formation. We present a heated brine migration test design, formulated with these complexities in mind. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.

  17. [Migration and urbanization in the Sahel. Consequences of the Sahelian migrations].

    Science.gov (United States)

    Traore, S

    1997-10-01

    The consequences of Sahelian migration are multiple and diverse. In rural areas there may be a loss of income in the short run and a reduced possibility of development in the long run. Apart from its implications for urban growth, Sahelian migration may have four series of consequences in the places of origin. In detaching peasants from their lands, migration may contribute to loss of appreciation and reverence for the lands. Attachment to the lands of the ancestors loses its meaning as soon as questions of survival or economic rationality are raised. Migration contributes to the restructuring of the societies of origin. Increasing monetarization of market relations and introduction of new needs create new norms that favor stronger integration into the world economy. Migration may cause a decline in production because of the loss of the most active population, and it changes the age and sex distribution of households and usually increases their dependency burden. The effects on fertility and mortality are less clear. The effects of migration on the zones of arrival in the Sahel depend on the type of area. Conflicts between natives and in-migrants are common in rural-rural migration. Degradation of land may result from the increased demands placed upon it. Migrants to cities in Africa, and especially in the Sahel, appear to conserve their cultural values and to transplant and reinterpret their village rules of solidarity.

  18. Douglas-fir plantations in Europe: a retrospective test of assisted migration to address climate change.

    Science.gov (United States)

    Isaac-Renton, Miriam G; Roberts, David R; Hamann, Andreas; Spiecker, Heinrich

    2014-08-01

    We evaluate genetic test plantations of North American Douglas-fir provenances in Europe to quantify how tree populations respond when subjected to climate regime shifts, and we examined whether bioclimate envelope models developed for North America to guide assisted migration under climate change can retrospectively predict the success of these provenance transfers to Europe. The meta-analysis is based on long-term growth data of 2800 provenances transferred to 120 European test sites. The model was generally well suited to predict the best performing provenances along north-south gradients in Western Europe, but failed to predict superior performance of coastal North American populations under continental climate conditions in Eastern Europe. However, model projections appear appropriate when considering additional information regarding adaptation of Douglas-fir provenances to withstand frost and drought, even though the model partially fails in a validation against growth traits alone. We conclude by applying the partially validated model to climate change scenarios for Europe, demonstrating that climate trends observed over the last three decades warrant changes to current use of Douglas-fir provenances in plantation forestry throughout Western and Central Europe. © 2014 John Wiley & Sons Ltd.

  19. Stereotactic core needle breast biopsy marker migration: An analysis of factors contributing to immediate marker migration.

    Science.gov (United States)

    Jain, Ashali; Khalid, Maria; Qureshi, Muhammad M; Georgian-Smith, Dianne; Kaplan, Jonah A; Buch, Karen; Grinstaff, Mark W; Hirsch, Ariel E; Hines, Neely L; Anderson, Stephan W; Gallagher, Katherine M; Bates, David D B; Bloch, B Nicolas

    2017-11-01

    To evaluate breast biopsy marker migration in stereotactic core needle biopsy procedures and identify contributing factors. This retrospective study analyzed 268 stereotactic biopsy markers placed in 263 consecutive patients undergoing stereotactic biopsies using 9G vacuum-assisted devices from August 2010-July 2013. Mammograms were reviewed and factors contributing to marker migration were evaluated. Basic descriptive statistics were calculated and comparisons were performed based on radiographically-confirmed marker migration. Of the 268 placed stereotactic biopsy markers, 35 (13.1%) migrated ≥1 cm from their biopsy cavity. Range: 1-6 cm; mean (± SD): 2.35 ± 1.22 cm. Of the 35 migrated biopsy markers, 9 (25.7%) migrated ≥3.5 cm. Patient age, biopsy pathology, number of cores, and left versus right breast were not associated with migration status (P> 0.10). Global fatty breast density (P= 0.025) and biopsy in the inner region of breast (P = 0.031) were associated with marker migration. Superior biopsy approach (P= 0.025), locally heterogeneous breast density, and t-shaped biopsy markers (P= 0.035) were significant for no marker migration. Multiple factors were found to influence marker migration. An overall migration rate of 13% supports endeavors of research groups actively developing new biopsy marker designs for improved resistance to migration. • Breast biopsy marker migration is documented in 13% of 268 procedures. • Marker migration is affected by physical, biological, and pathological factors. • Breast density, marker shape, needle approach etc. affect migration. • Study demonstrates marker migration prevalence; marker design improvements are needed.

  20. Safety and quality of food contact materials. Part 1: evaluation of analytical strategies to introduce migration testing into good manufacturing practice.

    Science.gov (United States)

    Feigenbaum, A; Scholler, D; Bouquant, J; Brigot, G; Ferrier, D; Franzl, R; Lillemarktt, L; Riquet, A M; Petersen, J H; van Lierop, B; Yagoubi, N

    2002-02-01

    The results of a research project (EU AIR Research Programme CT94-1025) aimed to introduce control of migration into good manufacturing practice and into enforcement work are reported. Representative polymer classes were defined on the basis of chemical structure, technological function, migration behaviour and market share. These classes were characterized by analytical methods. Analytical techniques were investigated for identification of potential migrants. High-temperature gas chromatography was shown to be a powerful method and 1H-magnetic resonance provided a convenient fingerprint of plastic materials. Volatile compounds were characterized by headspace techniques, where it was shown to be essential to differentiate volatile compounds desorbed from those generated during the thermal desorption itself. For metal trace analysis, microwave mineralization followed by atomic absorption was employed. These different techniques were introduced into a systematic testing scheme that is envisaged as being suitable both for industrial control and for enforcement laboratories. Guidelines will be proposed in the second part of this paper.

  1. Migration of nanosized layered double hydroxide platelets from polylactide nanocomposite films

    DEFF Research Database (Denmark)

    Schmidt, Bjørn; Katiyar, Vimal; Plackett, David

    2011-01-01

    (OLLA). This is the first reported investigation on the migration properties of PLA-LDH nanocomposite films. The tests were carried out as part of an overall assessment of the suitability of such films for use as food contact materials (FCM). Total migration was determined according to a European...... detected arises from the use of organotin catalysts in the manufacture of PLA....

  2. Mkit: A Cell Migration Assay Based on Microfluidic Device and Smartphone

    Science.gov (United States)

    Yang, Ke; Wu, Jiandong; Peretz-Soroka, Hagit; Zhu, Ling; Li, Zhigang; Sang, Yaoshuo; Hipolito, Jolly; Zhang, Michael; Santos, Susy; Hillier, Craig; de Faria, Ricardo Lobato; Liu, Yong; Lin, Francis

    2017-01-01

    Mobile sensing based on the integration of microfluidic device and smartphone, so-called MS2 technology, has enabled many applications over recent years, and continues to stimulate growing interest in both research communities and industries. In particular, it has been envisioned that MS2 technology can be developed for various cell functional assays to enable basic research and clinical applications. Toward this direction, in this paper, we describe the development of a MS2-based cell functional assay for testing cell migration (the Mkit). The system is constructed as an integrated test kit, which includes microfluidic chips, a smartphone-based imaging platform, the phone apps for image capturing and data analysis, and a set of reagent and accessories for performing the cell migration assay. We demonstrated that the Mkit can effectively measure purified neutrophil and cancer cell chemotaxis. Furthermore, neutrophil chemotaxis can be tested from a drop of whole blood using the Mkit with red blood cell (RBC) lysis. The effects of chemoattractant dose and gradient profile on neutrophil chemotaxis were also tested using the Mkit. In addition to research applications, we demonstrated the effective use of the Mkit for on-site test at the hospital and for testing clinical samples from chronic obstructive pulmonary disease patient. Thus, this developed Mkit provides an easy and integrated experimental platform for cell migration related research and potential medical diagnostic applications. PMID:28772229

  3. Return migration as failure or success? : The determinants of return migration intentions among Moroccan migrants in Europe

    NARCIS (Netherlands)

    de Haas, H.; Fokkema, T.; Fihri, M.F.

    2015-01-01

    Different migration theories generate competing hypotheses with regard to determinants of return migration. While neoclassical migration theory associates migration to the failure to integrate at the destination, the new economics of labour migration sees return migration as the logical stage after

  4. Evaluation of T-lymphocyte populations in humans exposed to action of beryllium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ermakova, N G

    1977-10-01

    Earlier studies in vitro on beryllosis and cellular immunity, and knowledge of the role of T-cells in development of cellular immunity suggested usefulness of a quantitative determination of T-cell populations in beryllosis. Assay was based on the test for spontaneous rosette formation in beryllosis patients and in healthy workers who come in contact with Be compounds (Jondal, modified by M. A. Stenina) and on the leucocyte migration inhibition reaction (Soborg and Bendixen). A large range of changes were revealed in population size and in adhesion qualities of T-lymphocytes in the patients and in those exposed to Be. The test for spontaneous rosette formation was found to be sufficiently indicative for use in study of beryllosis pathogenesis and to correlate with the state of activity of the disease.

  5. Characteristics of meniscus progenitor cells migrated from injured meniscus.

    Science.gov (United States)

    Seol, Dongrim; Zhou, Cheng; Brouillette, Marc J; Song, Ino; Yu, Yin; Choe, Hyeong Hun; Lehman, Abigail D; Jang, Kee W; Fredericks, Douglas C; Laughlin, Barbara J; Martin, James A

    2017-09-01

    Serious meniscus injuries seldom heal and increase the risk for knee osteoarthritis; thus, there is a need to develop new reparative therapies. In that regard, stimulating tissue regeneration by autologous stem/progenitor cells has emerged as a promising new strategy. We showed previously that migratory chondrogenic progenitor cells (CPCs) were recruited to injured cartilage, where they showed a capability in situ tissue repair. Here, we tested the hypothesis that the meniscus contains a similar population of regenerative cells. Explant studies revealed that migrating cells were mainly confined to the red zone in normal menisci: However, these cells were capable of repopulating defects made in the white zone. In vivo, migrating cell numbers increased dramatically in damaged meniscus. Relative to non-migrating meniscus cells, migrating cells were more clonogenic, overexpressed progenitor cell markers, and included a larger side population. Gene expression profiling showed that the migrating population was more similar to CPCs than other meniscus cells. Finally, migrating cells equaled CPCs in chondrogenic potential, indicating a capacity for repair of the cartilaginous white zone of the meniscus. These findings demonstrate that, much as in articular cartilage, injuries to the meniscus mobilize an intrinsic progenitor cell population with strong reparative potential. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1966-1972, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  6. Effects of dynamic matrix remodelling on en masse migration of fibroblasts on collagen matrices.

    Science.gov (United States)

    Ozcelikkale, Altug; Dutton, J Craig; Grinnell, Frederick; Han, Bumsoo

    2017-10-01

    Fibroblast migration plays a key role during various physiological and pathological processes. Although migration of individual fibroblasts has been well studied, migration in vivo often involves simultaneous locomotion of fibroblasts sited in close proximity, so-called ' en masse migration', during which intensive cell-cell interactions occur. This study aims to understand the effects of matrix mechanical environments on the cell-matrix and cell-cell interactions during en masse migration of fibroblasts on collagen matrices. Specifically, we hypothesized that a group of migrating cells can significantly deform the matrix, whose mechanical microenvironment dramatically changes compared with the undeformed state, and the alteration of the matrix microenvironment reciprocally affects cell migration. This hypothesis was tested by time-resolved measurements of cell and extracellular matrix movement during en masse migration on collagen hydrogels with varying concentrations. The results illustrated that a group of cells generates significant spatio-temporal deformation of the matrix before and during the migration. Cells on soft collagen hydrogels migrate along tortuous paths, but, as the matrix stiffness increases, cell migration patterns become aligned with each other and show coordinated migration paths. As cells migrate, the matrix is locally compressed, resulting in a locally stiffened and dense matrix across the collagen concentration range studied. © 2017 The Author(s).

  7. Terrestrial planet formation in the presence of migrating super-Earths

    International Nuclear Information System (INIS)

    Izidoro, André; Morbidelli, Alessandro; Raymond, Sean N.

    2014-01-01

    Super-Earths with orbital periods less than 100 days are extremely abundant around Sun-like stars. It is unlikely that these planets formed at their current locations. Rather, they likely formed at large distances from the star and subsequently migrated inward. Here we use N-body simulations to study the effect of super-Earths on the accretion of rocky planets. In our simulations, one or more super-Earths migrate inward through a disk of planetary embryos and planetesimals embedded in a gaseous disk. We tested a wide range of migration speeds and configurations. Fast-migrating super-Earths (τ mig ∼ 0.01-0.1 Myr) only have a modest effect on the protoplanetary embryos and planetesimals. Sufficient material survives to form rocky, Earth-like planets on orbits exterior to the super-Earths'. In contrast, slowly migrating super-Earths shepherd rocky material interior to their orbits and strongly deplete the terrestrial planet-forming zone. In this situation any Earth-sized planets in the habitable zone are extremely volatile-rich and are therefore probably not Earth-like.

  8. Changes in timing of autumn migration in North European songbird populations

    DEFF Research Database (Denmark)

    Tøttrup, Anders Peter; Thorup, Kasper; Rahbek, Carsten

    2006-01-01

    Although studies of changes in the timing of passerine spring migration are numerous, less is known about timing of their autumn departure. We present phenological data on 22 species based on mist-netted birds caught on the Baltic island of Christiansø during autumn migration between 1976 and 1997...... departure (-0.0426 days year-1, P = 0.40). Testing the 12 species for which the entire migration period was included (thus excluding many long-distance migrants), we found an overall earlier departure (-0.18 days year-1, P = 0.007). Short-distance migrants tended to show earlier departure, while long...

  9. Migration and revolution

    Directory of Open Access Journals (Sweden)

    Nando Sigona

    2012-06-01

    Full Text Available The Arab Spring has not radically transformed migration patterns in the Mediterranean, and the label ‘migration crisis’ does not do justice to the composite and stratified reality.

  10. Migration of formaldehyde and melamine monomers from kitchen- and tableware made of melamine plastic

    DEFF Research Database (Denmark)

    Lund, K.H.; Petersen, J.H.

    2006-01-01

    Migration of one or both formaldehyde and/or melamine monomers was found in seven of ten tested melamine samples bought on the Danish market. The samples were a bowl, a jug, a mug, a ladle, and different cups and plates. No violation of the European Union-specific migration limits for melamine (30...... mg kg(-1)) and formaldehyde (15 mg kg(-1)) was found after three successive exposures to the food stimulant 3% acetic acid after 2 h at 70 degrees C. To investigate the effects of long-term use, migration tests were performed with two types of cups from a day nursery. Furthermore, medium-term use...

  11. Application of Post-stack migration to seismic data associated with fault structures

    Science.gov (United States)

    Koduru, Anitha; Mohanty, P. R.

    2015-06-01

    In hydrocarbon exploration, wave-equation migration techniques play an important role in imaging the complex geological structures. Usually, post-stack migration scheme is applied to the seismic data to improve the resolution with restoration of dipping reflectors to their true position. As a result, the migrated time sections are interpretable in terms of subsurface features. As a numerical study, three fault models are considered for the present study. First of all, synthetic time sections are generated corresponding to three models. Later, post stack migration schemes such as Gazdag(PS), Phase-shift with turning rays and reverse time migration (T-K) domain techniques are applied in order to judge the imaging accuracy, preservation of true amplitude and computational speed. All the three post stack time migrated sections delineate the structure with their throw.However, the reverse time migrations (T-K) clearly delineate the reflectors in restoring the throw properly with minimum computational time. In order to test the validity the numerical results, similar exercise has been undertaken using field seismic data of KG basin, India. The results indicates that the field migrated sections are imaged. But, the reverse time migration (T-K ) provides the best subsurface image with restoration of reflectors and collapse of diffracted events with least computational time. Gazdag (PS) and Phase-Shift with turning migrated section shows the reduction of amplitude whereas, the reverse time migration preserved the amplitude fully.

  12. Migration = cloning; aliasiing

    DEFF Research Database (Denmark)

    Hüttel, Hans; Kleist, Josva; Nestmann, Uwe

    1999-01-01

    In Obliq, a lexically scoped, distributed, object-oriented programming language, object migration was suggested as the creation of a copy of an object’s state at the target site, followed by turning the object itself into an alias, also called surrogate, for the remote copy. We consider the creat......In Obliq, a lexically scoped, distributed, object-oriented programming language, object migration was suggested as the creation of a copy of an object’s state at the target site, followed by turning the object itself into an alias, also called surrogate, for the remote copy. We consider...... the creation of object surrogates as an abstraction of the abovementioned style of migration. We introduce Øjeblik, a distribution-free subset of Obliq, and provide three different configuration-style semantics, which only differ in the respective aliasing model. We show that two of the semantics, one of which...... matches Obliq’s implementation, render migration unsafe, while our new proposal for a third semantics is provably safe. Our work suggests a straightforward repair of Obliq’s aliasing model such that it allows programs to safely migrate objects....

  13. SiMA: A simplified migration assay for analyzing neutrophil migration.

    Science.gov (United States)

    Weckmann, Markus; Becker, Tim; Nissen, Gyde; Pech, Martin; Kopp, Matthias V

    2017-07-01

    In lung inflammation, neutrophils are the first leukocytes migrating to an inflammatory site, eliminating pathogens by multiple mechanisms. The term "migration" describes several stages of neutrophil movement to reach the site of inflammation, of which the passage of the interstitium and basal membrane of the airway are necessary to reach the site of bronchial inflammation. Currently, several methods exist (e.g., Boyden Chamber, under-agarose assay, or microfluidic systems) to assess neutrophil mobility. However, these methods do not allow for parameterization on single cell level, that is, the individual neutrophil pathway analysis is still considered challenging. This study sought to develop a simplified yet flexible method to monitor and quantify neutrophil chemotaxis by utilizing commercially available tissue culture hardware, simple video microscopic equipment and highly standardized tracking. A chemotaxis 3D µ-slide (IBIDI) was used with different chemoattractants [interleukin-8 (IL-8), fMLP, and Leukotriene B4 (LTB 4 )] to attract neutrophils in different matrices like Fibronectin (FN) or human placental matrix. Migration was recorded for 60 min using phase contrast microscopy with an EVOS ® FL Cell Imaging System. The images were normalized and texture based image segmentation was used to generate neutrophil trajectories. Based on these spatio-temporal information a comprehensive parameter set is extracted from each time series describing the neutrophils motility, including velocity and directness and neutrophil chemotaxis. To characterize the latter one, a sector analysis was employed enabling the quantification of the neutrophils response to the chemoattractant. Using this hard- and software framework we were able to identify typical migration profiles of the chemoattractants IL-8, fMLP, and LTB 4 , the effect of the matrices FN versus HEM as well as the response to different medications (Prednisolone). Additionally, a comparison of four asthmatic and

  14. Least-squares reverse time migration of multiples

    KAUST Repository

    Zhang, Dongliang

    2013-12-06

    The theory of least-squares reverse time migration of multiples (RTMM) is presented. In this method, least squares migration (LSM) is used to image free-surface multiples where the recorded traces are used as the time histories of the virtual sources at the hydrophones and the surface-related multiples are the observed data. For a single source, the entire free-surface becomes an extended virtual source where the downgoing free-surface multiples more fully illuminate the subsurface compared to the primaries. Since each recorded trace is treated as the time history of a virtual source, knowledge of the source wavelet is not required and the ringy time series for each source is automatically deconvolved. If the multiples can be perfectly separated from the primaries, numerical tests on synthetic data for the Sigsbee2B and Marmousi2 models show that least-squares reverse time migration of multiples (LSRTMM) can significantly improve the image quality compared to RTMM or standard reverse time migration (RTM) of primaries. However, if there is imperfect separation and the multiples are strongly interfering with the primaries then LSRTMM images show no significant advantage over the primary migration images. In some cases, they can be of worse quality. Applying LSRTMM to Gulf of Mexico data shows higher signal-to-noise imaging of the salt bottom and top compared to standard RTM images. This is likely attributed to the fact that the target body is just below the sea bed so that the deep water multiples do not have strong interference with the primaries. Migrating a sparsely sampled version of the Marmousi2 ocean bottom seismic data shows that LSM of primaries and LSRTMM provides significantly better imaging than standard RTM. A potential liability of LSRTMM is that multiples require several round trips between the reflector and the free surface, so that high frequencies in the multiples suffer greater attenuation compared to the primary reflections. This can lead to lower

  15. Migration of methane into groundwater from leaking production wells near Lloydminster

    International Nuclear Information System (INIS)

    1995-03-01

    The problem of migration of methane from leaking oil and gas wells into aquifers in the Lloydminster area in Saskatchewan, was discussed. A study was conducted to determine if the methane in shallow aquifers near the leaking wells, came from the wells or occurred naturally. Migration rate in aquifers, concentration gradients and approximate flux rates of methane from leaking wells to shallow aquifers, were studied. The methods of investigation included drilling of test holes at selected sites, installation of monitoring wells, purging of wells, pumping tests and water level monitoring, sampling and analyses for dissolved methane. The relatively high methane concentrations in many of the monitoring wells indicated the presence of a methane plume that has migrated from the production well. It was suggested that other leaky well sites in the area should be investigated to determine if similar plumes were present. 18 refs., 5 tabs., 13 figs

  16. Development of migration prediction system (MIGSTEM) for cationic species of radionuclides through soil layers

    International Nuclear Information System (INIS)

    Ohnuki, Toshihiko; Takebe, Shinichi; Yamamoto, Tadatoshi

    1989-01-01

    The migration prediction system (MIGSTEM) has been developed for estimating the migration of cationic species of radionuclides through soil layers systematically. The MIGSTEM consists of the migration experiments, the one-dimensional fitting code (inverse analysis code) for determining retardation factor and dispersivity (migration factors) and the three-dimensional differential code (prediction code) for estimating the migration of the radionuclides. The migration experiments are carried out for obtaining the concentration profiles of the radionuclides in unsaturated and saturated soil layers. Using the inverse analysis code, the migration factors are obtained at one time by fitting the concentration profiles calculated to those observed. The prediction code can give the contours of concentration and the one-dimensional concentration profiles at selected time, as well as the changing in the concentration at a selected position with time. The validity of the MIGSTEM was obtained by the benchmark test on the prediction and inverse analysis codes. The MIGSTEM was applied to estimate the migration of Sr 2+ through the sandy soil. (author)

  17. Migration kinetics of mineral oil hydrocarbons from recycled paperboard to dry food: monitoring of two real cases.

    Science.gov (United States)

    Lorenzini, R; Biedermann, M; Grob, K; Garbini, D; Barbanera, M; Braschi, I

    2013-01-01

    Mineral oil hydrocarbons present in printing inks and recycled paper migrate from paper-based food packaging to foods primarily through the gas phase. Migration from two commercial products packed in recycled paperboard, i.e. muesli and egg pasta, was monitored up to the end of their shelf life (1 year) to study the influence of time, storage conditions, food packaging structure and temperature. Mineral oil saturated and aromatic hydrocarbons (MOSH and MOAH, respectively), and diisopropyl naphthalenes (DIPN) were monitored using online HPLC-GC/FID. Storage conditions were: free standing, shelved, and packed in transport boxes of corrugated board, to represent domestic, supermarket and warehouse storage, respectively. Migration to food whose packs were kept in transport boxes was the highest, especially after prolonged storage, followed by shelved and free-standing packs. Tested temperatures were representative of refrigeration, room temperature, storage in summer months and accelerated migration testing. Migration was strongly influenced by temperature: for egg pasta directly packed in paperboard, around 30 mg kg⁻¹ of MOSH migrated in 8 months at 20°C, but in only 1 week at 40°C. Muesli was contained into an internal polyethylene bag, which firstly adsorbed hydrocarbons and later released them partly towards the food. Differently, the external polypropylene bag, containing pasta and recycled paper tray, strongly limited the migration towards the atmosphere and gave rise to the highest level of food contamination. Tests at increased temperatures not only accelerated migration, but also widened the migration of hydrocarbons to higher molecular masses, highlighting thus a difficult interpretation of data from accelerated simulation.

  18. Evaluation of upward migration around a deep injection well

    International Nuclear Information System (INIS)

    Chia, Yeeping; Chiu, J.

    1994-01-01

    The long-term containment of injected wastes in the deep subsurface is expected to be achieved under suitable geologic and hydrologic conditions and by the use of competent engineering practices. Field experiences, however, indicate that waste containment may be affected by hydrologic conduits around the injection well. To assess the potential effects of these conduits, upward migration of injected waste is examined through the use of numerical models under various conditions. Test results indicate that without any preferential hydrologic conduits, most of the injected waste moves laterally in the injection interval, whereas only a small amount of waste migrates upward into the containment interval. When vertical fractures in the disturbed zone or defects in the cement seal around the wellbore exist, the contaminant can move rapidly upward along these conduits to an overlying aquifer, from which it migrates in the lateral direction. The contamination of the overlying aquifer that results from the upward migration of injected waste through these conduits cannot be impeded by a thick, low-permeability containment interval. However, when permeable interbeds exist within the containment interval, a significant portion of the waste migrating upward can be diverted laterally before reaching the overlying aquifer. The front of built-up pressure can reach the aquifer or permeable interbed immediately overlying the injection interval through the preferential hydrologic conduits shortly after the injection starts, but it cannot move farther upward because of pressure dissipation in the permeable formation. This study suggests that the injected waste has the potential to migrate upward into overlying formations through preferential migration conduits around the wellbore

  19. MIGRATION OF SMALL MOONS IN SATURN's RINGS

    Energy Technology Data Exchange (ETDEWEB)

    Bromley, Benjamin C. [Department of Physics and Astronomy, University of Utah, 115 S 1400 E, Rm 201, Salt Lake City, UT 84112 (United States); Kenyon, Scott J., E-mail: bromley@physics.utah.edu, E-mail: skenyon@cfa.harvard.edu [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States)

    2013-02-20

    The motions of small moons through Saturn's rings provide excellent tests of radial migration models. In theory, torque exchange between these moons and ring particles leads to radial drift. We predict that moons with Hill radii r {sub H} {approx} 2-24 km should migrate through the A ring in 1000 yr. In this size range, moons orbiting in an empty gap or in a full ring eventually migrate at the same rate. Smaller moons or moonlets-such as the propellers-are trapped by diffusion of disk material into corotating orbits, creating inertial drag. Larger moons-such as Pan or Atlas-do not migrate because of their own inertia. Fast migration of 2-24 km moons should eliminate intermediate-size bodies from the A ring and may be responsible for the observed large-radius cutoff of r {sub H} {approx} 1-2 km in the size distribution of the A ring's propeller moonlets. Although the presence of Daphnis (r {sub H} Almost-Equal-To 5 km) inside the Keeler gap challenges this scenario, numerical simulations demonstrate that orbital resonances and stirring by distant, larger moons (e.g., Mimas) may be important factors. For Daphnis, stirring by distant moons seems the most promising mechanism to halt fast migration. Alternatively, Daphnis may be a recent addition to the ring that is settling into a low inclination orbit in {approx}10{sup 3} yr prior to a phase of rapid migration. We provide predictions of observational constraints required to discriminate among possible scenarios for Daphnis.

  20. Migration into art

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    This book addresses a topic of increasing importance to artists, art historians and scholars of cultural studies, migration studies and international relations: migration as a profoundly transforming force that has remodelled artistic and art institutional practices across the world. It explores...... contemporary art's critical engagement with migration and globalisation as a key source for improving our understanding of how these processes transform identities, cultures, institutions and geopolitics. The author explores three interwoven issues of enduring interest: identity and belonging, institutional...

  1. What's driving migration?

    Science.gov (United States)

    Kane, H

    1995-01-01

    During the 1990s investment in prevention of international or internal migration declined, and crisis intervention increased. The budgets of the UN High Commissioner for Refugees and the UN Development Program remained about the same. The operating assumption is that war, persecution, famine, and environmental and social disintegration are inevitable. Future efforts should be directed to stabilizing populations through investment in sanitation, public health, preventive medicine, land tenure, environmental protection, and literacy. Forces pushing migration are likely to increase in the future. Forces include depletion of natural resources, income disparities, population pressure, and political disruption. The causes of migration are not constant. In the past, migration occurred during conquests, settlement, intermarriage, or religious conversion and was a collective movement. Current migration involves mass movement of individuals and the struggle to survive. There is new pressure to leave poor squatter settlements and the scarcities in land, water, and food. The slave trade between the 1500s and the 1800s linked continents, and only 2-3 million voluntarily crossed national borders. Involuntary migration began in the early 1800s when European feudal systems were in a decline, and people sought freedom. Official refugees, who satisfy the strict 1951 UN definition, increased from 15 million in 1980 to 23 million in 1990 but remained a small proportion of international migrants. Much of the mass movement occurs between developing countries. Migration to developed countries is accompanied by growing intolerance, which is misinformed. China practices a form of "population transfer" in Tibet in order to dilute Tibetan nationalism. Colonization of countries is a new less expensive form of control over territory. Eviction of minorities is another popular strategy in Iraq. Public works projects supported by foreign aid displace millions annually. War and civil conflicts

  2. Sparse least-squares reverse time migration using seislets

    KAUST Repository

    Dutta, Gaurav; Schuster, Gerard T.

    2015-01-01

    the iterations. These dips can be estimated from the standard migration image or from the gradient using plane-wave destruction filters or structural tensors. Numerical tests on synthetic datasets demonstrate the benefits of this method for mitigation of aliasing

  3. Migration of fresh and cryopreserved human spermatozoa in polyacrylamide gel.

    Science.gov (United States)

    Goldstein, M C; Wix, L S; Foote, R H; Feldschuh, R; Feldschuh, J

    1982-05-01

    The ability of freshly collected and frozen human spermatozoa to migrate in round capillary tubes containing specially formulated polyacrylamide gel was investigated, using 33 ejaculates from 27 donors. Each semen sample was divided; one portion was left undiluted, and the other portion was diluted to 50 x 10(6) sperm/ml. Glycerol was used as the cryoprotectant. The percentage of motile sperm cells was determined before and after freezing. Fresh semen contained a higher percentage of motile cells, which migrated farther than those of cryopreserved-thawed semen. Various correlations between the percentage of motile sperm and migration distance ranged from 0.57 to 0.62. There was a low positive correlation of migration distance with sperm cell concentration per milliliter, r = 0.25 to 0.34; and thus adjusting semen samples to a standard sperm concentration improved the accuracy of the test only slightly. The regression coefficient of migration distance on the percentage of motile sperm in fresh semen was 0.65, indicating that for each 10% increase in sperm motility, migration distance is predicted to increase 6.5 mm. Five batches of polyacrylamide gel gave uniform results, and the application of this stable gel to fertility investigations is discussed.

  4. Recovery Migration to the City of New Orleans after Hurricane Katrina: A Migration Systems Approach.

    Science.gov (United States)

    Fussell, Elizabeth; Curtis, Katherine J; Dewaard, Jack

    2014-03-01

    Hurricane Katrina's effect on the population of the City of New Orleans provides a model of how severe weather events, which are likely to increase in frequency and strength as the climate warms, might affect other large coastal cities. Our research focuses on changes in the migration system - defined as the system of ties between Orleans Parish and all other U.S. counties - between the pre-disaster (1999-2004) and recovery (2007-2009) periods. Using Internal Revenue Service county-to-county migration flow data, we find that in the recovery period Orleans Parish increased the number of migration ties with and received larger migration flows from nearby counties in the Gulf of Mexico coastal region, thereby spatially concentrating and intensifying the in-migration dimension of this predominantly urban system, while the out-migration dimension contracted and had smaller flows. We interpret these changes as the migration system relying on its strongest ties to nearby and less damaged counties to generate recovery in-migration.

  5. The Effect Of Fine Particle Migration On Void Ratio Of Gap Graded Soil

    Directory of Open Access Journals (Sweden)

    Mayssa Salem Flayh

    2017-12-01

    Full Text Available Soil is exposed to the migration of fine particles in some cases because of some conditions including excavation and the presence of a level of groundwater which is equal to the level of soil in this case and because of the existence of this water leakage which would work on the migration of fine particles in the soil. This migration of fine particles will change the structure of the soil and change its properties. In this study we will know the change in the properties of the fouling soil due to the migration of fine particles and four types of soil. The first type does not contain fine particles and the second type the third and the fourth contains 10 20 30 granules respectively and tests were carried out for these soils Atterberg limits sieve analysis specific gravity shear resistance permeability modified Procter consolidation. A model was created to simulate the reality of soil exposed to excavations. Three levels were selected in the model to compare the results of each of the four soils under study. The total number of models 24 model through laboratory work obtained the initial and final voids ratio before and after aft the initial and final voids ratio er the particles migration. After these tests it was found that the migration of granules clearly affects the increase in the voids ratio.

  6. Regional Redistribution and Migration

    DEFF Research Database (Denmark)

    Manasse, Paolo; Schultz, Christian

    We study a model with free migration between a rich and a poor region. Since there is congestion, the rich region has an incentive to give the poor region a transfer in order to reduce immigration. Faced with free migration, the rich region voluntarily chooses a transfer, which turns out...... to be equal to that a social planner would choose. Provided migration occurs in equilibrium, this conclusion holds even in the presence of moderate mobility costs. However, large migration costs will lead to suboptimal transfers in the market solution...

  7. Testing and intercomparison of model predictions of radionuclide migration from a hypothetical area source

    International Nuclear Information System (INIS)

    O'Brien, R.S.; Yu, C.; Zeevaert, T.; Olyslaegers, G.; Amado, V.; Setlow, L.W.; Waggitt, P.W.

    2008-01-01

    This work was carried out as part of the International Atomic Energy Agency's EMRAS program. One aim of the work was to develop scenarios for testing computer models designed for simulating radionuclide migration in the environment, and to use these scenarios for testing the models and comparing predictions from different models. This paper presents the results of the development and testing of a hypothetical area source of NORM waste/residue using two complex computer models and one screening model. There are significant differences in the methods used to model groundwater flow between the complex models. The hypothetical source was used because of its relative simplicity and because of difficulties encountered in finding comprehensive, well-validated data sets for real sites. The source consisted of a simple repository of uniform thickness, with 1 Bq g -1 of uranium-238 ( 238 U) (in secular equilibrium with its decay products) distributed uniformly throughout the waste. These approximate real situations, such as engineered repositories, waste rock piles, tailings piles and landfills. Specification of the site also included the physical layout, vertical stratigraphic details, soil type for each layer of material, precipitation and runoff details, groundwater flow parameters, and meteorological data. Calculations were carried out with and without a cover layer of clean soil above the waste, for people working and living at different locations relative to the waste. The predictions of the two complex models showed several differences which need more detailed examination. The scenario is available for testing by other modelers. It can also be used as a planning tool for remediation work or for repository design, by changing the scenario parameters and running the models for a range of different inputs. Further development will include applying models to real scenarios and integrating environmental impact assessment methods with the safety assessment tools currently

  8. Human migration patterns in Yemen and implications for reconstructing prehistoric population movements.

    Directory of Open Access Journals (Sweden)

    Aida T Miró-Herrans

    Full Text Available Population migration has played an important role in human evolutionary history and in the patterning of human genetic variation. A deeper and empirically-based understanding of human migration dynamics is needed in order to interpret genetic and archaeological evidence and to accurately reconstruct the prehistoric processes that comprise human evolutionary history. Current empirical estimates of migration include either short time frames (i.e. within one generation or partial knowledge about migration, such as proportion of migrants or distance of migration. An analysis of migration that includes both proportion of migrants and distance, and direction over multiple generations would better inform prehistoric reconstructions. To evaluate human migration, we use GPS coordinates from the place of residence of the Yemeni individuals sampled in our study, their birthplaces and their parents' and grandparents' birthplaces to calculate the proportion of migrants, as well as the distance and direction of migration events between each generation. We test for differences in these values between the generations and identify factors that influence the probability of migration. Our results show that the proportion and distance of migration between females and males is similar within generations. In contrast, the proportion and distance of migration is significantly lower in the grandparents' generation, most likely reflecting the decreasing effect of technology. Based on our results, we calculate the proportion of migration events (0.102 and mean and median distances of migration (96 km and 26 km for the grandparent's generation to represent early times in human evolution. These estimates can serve to set parameter values of demographic models in model-based methods of prehistoric reconstruction, such as approximate Bayesian computation. Our study provides the first empirically-based estimates of human migration over multiple generations in a developing

  9. Modeling Coupled THM Processes and Brine Migration in Salt at High Temperatures

    International Nuclear Information System (INIS)

    Rutqvist, Jonny; Blanco-Martin, Laura; Molins, Sergi; Trebotich, David; Birkholzer, Jens

    2015-01-01

    In this report, we present FY2015 progress by Lawrence Berkeley National Laboratory (LBNL) related to modeling of coupled thermal-hydrological-mechanical-chemical (THMC) processes in salt and their effect on brine migration at high temperatures. This is a combined milestone report related to milestone Salt R&D Milestone ''Modeling Coupled THM Processes and Brine Migration in Salt at High Temperatures'' (M3FT-15LB0818012) and the Salt Field Testing Milestone (M3FT-15LB0819022) to support the overall objectives of the salt field test planning.

  10. Modeling Coupled THM Processes and Brine Migration in Salt at High Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Rutqvist, Jonny [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Blanco-Martin, Laura [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Molins, Sergi [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Trebotich, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Birkholzer, Jens [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-09-01

    In this report, we present FY2015 progress by Lawrence Berkeley National Laboratory (LBNL) related to modeling of coupled thermal-hydrological-mechanical-chemical (THMC) processes in salt and their effect on brine migration at high temperatures. This is a combined milestone report related to milestone Salt R&D Milestone “Modeling Coupled THM Processes and Brine Migration in Salt at High Temperatures” (M3FT-15LB0818012) and the Salt Field Testing Milestone (M3FT-15LB0819022) to support the overall objectives of the salt field test planning.

  11. Malaysia and forced migration

    Directory of Open Access Journals (Sweden)

    Arzura Idris

    2012-06-01

    Full Text Available This paper analyzes the phenomenon of “forced migration” in Malaysia. It examines the nature of forced migration, the challenges faced by Malaysia, the policy responses and their impact on the country and upon the forced migrants. It considers forced migration as an event hosting multifaceted issues related and relevant to forced migrants and suggests that Malaysia has been preoccupied with the issue of forced migration movements. This is largely seen in various responses invoked from Malaysia due to “south-south forced migration movements.” These responses are, however, inadequate in terms of commitment to the international refugee regime. While Malaysia did respond to economic and migration challenges, the paper asserts that such efforts are futile if she ignores issues critical to forced migrants.

  12. Latitudinal migration of sunspots based on the ESAI database

    Science.gov (United States)

    Zhang, Juan; Li, Fu-Yu; Feng, Wen

    2018-01-01

    The latitudinal migration of sunspots toward the equator, which implies there is propagation of the toroidal magnetic flux wave at the base of the solar convection zone, is one of the crucial observational bases for the solar dynamo to generate a magnetic field by shearing of the pre-existing poloidal magnetic field through differential rotation. The Extended time series of Solar Activity Indices (ESAI) elongated the Greenwich observation record of sunspots by several decades in the past. In this study, ESAI’s yearly mean latitude of sunspots in the northern and southern hemispheres during the years 1854 to 1985 is utilized to statistically test whether hemispherical latitudinal migration of sunspots in a solar cycle is linear or nonlinear. It is found that a quadratic function is statistically significantly better at describing hemispherical latitudinal migration of sunspots in a solar cycle than a linear function. In addition, the latitude migration velocity of sunspots in a solar cycle decreases as the cycle progresses, providing a particular constraint for solar dynamo models. Indeed, the butterfly wing pattern with a faster latitudinal migration rate should present stronger solar activity with a shorter cycle period, and it is located at higher latitudinal position, giving evidence to support the Babcock-Leighton dynamo mechanism.

  13. Managing migration: the Brazilian case

    OpenAIRE

    Eduardo L. G. Rios-Neto

    2005-01-01

    The objective of this paper is to present the Brazilian migration experience and its relationship with migration management. The article is divided into three parts. First, it reviews some basic facts regarding Brazilian immigration and emigration processes. Second, it focuses on some policy and legal issues related to migration. Finally, it addresses five issues regarding migration management in Brazil.

  14. Migration og etnicitet

    DEFF Research Database (Denmark)

    Christiansen, Connie Carøe

    2004-01-01

    Migration og etnicitet er aktuelle og forbundne fænomener, idet migration øger berøringsfladerne mellem befolkningsgrupper. Etniciteter formes i takt med at grænser drages imellem disse grupper. Imod moderniserings-teoriernes forventning forsvandt etnicitet ikke som en traditionel eller oprindelig...... måde at skabe tilhørsforhold på; globalt set fremstår vor tid istedet som en "migrationens tidsalder", der tilsyneladende også er en tidsalder, hvor kulturelle særtræk, i form af etnicitet, udgør vigtige linjer, hvorefter grupper skilller sig ud fra hinanden. Både migration og etnicitet bringer fokus...... den finder sted i modtagerlandet, men nyere perspektiver på migration, som begreber om medborgerskab, transnationalisme og diaspora er eksponenter for, søger udover den nationalstatslige ramme og inddrager konsekvenserne af migrationen for afsenderlande....

  15. Mechanisms and models of 137Cs migration in soil

    International Nuclear Information System (INIS)

    Frid, A.S.

    1999-01-01

    The most wide-spread mechanisms and models of the 137 Cs isotope migration in soil are considered because of urgency of this problem conditioned by global fallout during nuclear weapon tests and contamination of territories due to accidents on nuclear objects (including the East Urals and ChNPP accident). It is shown that the 137 Cs migration models with an account of the sorption-desorption kinetics have from the practical adequacy certain advantage in comparison with other models, though they are mathematically more complex and require complex calculations [ru

  16. The physiological basis of the migration continuum in brown trout (Salmo trutta).

    Science.gov (United States)

    Boel, Mikkel; Aarestrup, Kim; Baktoft, Henrik; Larsen, Torben; Søndergaard Madsen, Steffen; Malte, Hans; Skov, Christian; Svendsen, Jon C; Koed, Anders

    2014-01-01

    Partial migration is common in many animal taxa; however, the physiological variation underpinning migration strategies remains poorly understood. Among salmonid fishes, brown trout (Salmo trutta) is one of the species that exhibits the most complex variation in sympatric migration strategies, expressed as a migration continuum, ranging from residency to anadromy. In looking at brown trout, our objective with this study was to test the hypothesis that variation in migration strategies is underpinned by physiological variation. Prior to migration, physiological samples were taken from fish in the stream and then released at the capture site. Using telemetry, we subsequently classified fish as resident, short-distance migrants (potamodromous), or long-distance migrants (potentially anadromous). Our results revealed that fish belonging to the resident strategy differed from those exhibiting any of the two migratory strategies. Gill Na,K-ATPase activity, condition factor, and indicators of nutritional status suggested that trout from the two migratory strategies were smoltified and energetically depleted before leaving the stream, compared to those in the resident strategy. The trout belonging to the two migratory strategies were generally similar; however, lower triacylglycerides levels in the short-distance migrants indicated that they were more lipid depleted prior to migration compared with the long-distance migrants. In the context of migration cost, we suggest that additional lipid depletion makes migrants more inclined to terminate migration at the first given feeding opportunity, whereas individuals that are less lipid depleted will migrate farther. Collectively, our data suggest that the energetic state of individual fish provides a possible mechanism underpinning the migration continuum in brown trout.

  17. Mkit: A cell migration assay based on microfluidic device and smartphone.

    Science.gov (United States)

    Yang, Ke; Wu, Jiandong; Peretz-Soroka, Hagit; Zhu, Ling; Li, Zhigang; Sang, Yaoshuo; Hipolito, Jolly; Zhang, Michael; Santos, Susy; Hillier, Craig; de Faria, Ricardo Lobato; Liu, Yong; Lin, Francis

    2018-01-15

    Mobile sensing based on the integration of microfluidic device and smartphone, so-called MS 2 technology, has enabled many applications over recent years, and continues to stimulate growing interest in both research communities and industries. In particular, it has been envisioned that MS 2 technology can be developed for various cell functional assays to enable basic research and clinical applications. Toward this direction, in this paper, we describe the development of a MS 2 -based cell functional assay for testing cell migration (the M kit ). The system is constructed as an integrated test kit, which includes microfluidic chips, a smartphone-based imaging platform, the phone apps for image capturing and data analysis, and a set of reagent and accessories for performing the cell migration assay. We demonstrated that the M kit can effectively measure purified neutrophil and cancer cell chemotaxis. Furthermore, neutrophil chemotaxis can be tested from a drop of whole blood using the M kit with red blood cell (RBC) lysis. The effects of chemoattractant dose and gradient profile on neutrophil chemotaxis were also tested using the M kit . In addition to research applications, we demonstrated the effective use of the M kit for on-site test at the hospital and for testing clinical samples from chronic obstructive pulmonary disease patient. Thus, this developed M kit provides an easy and integrated experimental platform for cell migration related research and potential medical diagnostic applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Questions of migration and belonging: understandings of migration under neoliberalism in Ecuador.

    Science.gov (United States)

    Lawson, V

    1999-01-01

    This paper explores alternative understandings and experiences of migration under neoliberalism in Ecuador. Through the case study, the study examines migrants' multiple motivations for mobility and their ambivalence toward the process. Insights from the transnational migration literature were drawn in order to think through the implications of an increasingly contradictory context of economic modernization and its impact upon the sense of possibilities and belonging of migrants. In-depth interviews with urban-destined migrants in Ecuador were drawn to argue that mobility produces ambivalent development subjects. This argument is developed in three sections. First, the paper centers on the epistemological and theoretical basis for the relevance of migrant narratives in extending theorizations of migration. Second, in-depth interviews with migrants to Quito are drawn to explore migrants' sense of belonging and regional affiliation, identity formation through migration, and experiences of alienation and disruption in their lives. Lastly, this paper concludes with a retheorization of the role of migration places in the migrant identity construction.

  19. Seasonal associations with urban light pollution for nocturnally migrating bird populations.

    Science.gov (United States)

    La Sorte, Frank A; Fink, Daniel; Buler, Jeffrey J; Farnsworth, Andrew; Cabrera-Cruz, Sergio A

    2017-11-01

    The spatial extent and intensity of artificial light at night (ALAN) has increased worldwide through the growth of urban environments. There is evidence that nocturnally migrating birds are attracted to ALAN, and there is evidence that nocturnally migrating bird populations are more likely to occur in urban areas during migration, especially in the autumn. Here, we test if urban sources of ALAN are responsible, at least in part, for these observed urban associations. We use weekly estimates of diurnal occurrence and relative abundance for 40 nocturnally migrating bird species that breed in forested environments in North America to assess how associations with distance to urban areas and ALAN are defined across the annual cycle. Migratory bird populations presented stronger than expected associations with shorter distances to urban areas during migration, and stronger than expected association with higher levels of ALAN outside and especially within urban areas during migration. These patterns were more pronounced during autumn migration, especially within urban areas. Outside of the two migration periods, migratory bird populations presented stronger than expected associations with longer distances to urban areas, especially during the nonbreeding season, and weaker than expected associations with the highest levels of ALAN outside and especially within urban areas. These findings suggest that ALAN is associated with higher levels of diurnal abundance along the boundaries and within the interior of urban areas during migration, especially in the autumn when juveniles are undertaking their first migration journey. These findings support the conclusion that urban sources of ALAN can broadly effect migratory behavior, emphasizing the need to better understand the implications of ALAN for migratory bird populations. © 2017 John Wiley & Sons Ltd.

  20. Fitness consequences of timing of migration and breeding in cormorants.

    Directory of Open Access Journals (Sweden)

    Phillip Gienapp

    Full Text Available In most bird species timing of breeding affects reproductive success whereby early breeding is favoured. In migratory species migration time, especially arrival at the breeding grounds, and breeding time are expected to be correlated. Consequently, migration time should also have fitness consequences. However, in contrast to breeding time, evidence for fitness consequences of migration time is much more limited. Climate change has been shown to negatively affect the synchrony between trophic levels thereby leading to directional selection on timing but again direct evidence in avian migration time is scarce. We here analysed fitness consequences of migration and breeding time in great cormorants and tested whether climate change has led to increased selection on timing using a long-term data set from a breeding colony on the island of Vorsø (Denmark. Reproductive success, measured as number of fledglings, correlated with breeding time and arrival time at the colony and declined during the season. This seasonal decline became steeper during the study period for both migration and breeding time and was positively correlated to winter/spring climate, i.e. selection was stronger after warmer winters/springs. However, the increasing selection pressure on timing seems to be unrelated to climate change as the climatic variables that were related to selection strength did not increase during the study period. There is indirect evidence that phenology or abundances of preferred prey species have changed which could have altered selection on timing of migration and breeding.

  1. The European Crisis and Migration to Germany: Expectations and the Diversion of Migration Flows

    OpenAIRE

    Brücker, Herbert; Bertoli, Simone; Fernández-Huertas Moraga, Jesús

    2013-01-01

    The European crisis has diverted migration flows away from countries affected by the recession towards Germany. The diversion process creates a challenge for traditional discrete-choice models that assume that only bilateral factors account for dyadic migration rates. This paper shows how taking into account the sequential nature of migration decisions leads to write the bilateral migration rate as a function of expectations about the evolution of economic conditions in alternative destinatio...

  2. Attenuation compensation in least-squares reverse time migration using the visco-acoustic wave equation

    KAUST Repository

    Dutta, Gaurav

    2013-08-20

    Attenuation leads to distortion of amplitude and phase of seismic waves propagating inside the earth. Conventional acoustic and least-squares reverse time migration do not account for this distortion which leads to defocusing of migration images in highly attenuative geological environments. To account for this distortion, we propose to use the visco-acoustic wave equation for least-squares reverse time migration. Numerical tests on synthetic data show that least-squares reverse time migration with the visco-acoustic wave equation corrects for this distortion and produces images with better balanced amplitudes compared to the conventional approach. © 2013 SEG.

  3. Migration of perfluoroalkyl acids from food packaging to food simulants.

    Science.gov (United States)

    Xu, Y; Noonan, G O; Begley, T H

    2013-01-01

    A broad range of fluorochemicals is used to impart oil and water barrier properties to paper and paperboard food packaging. Many of the fluorochemicals are applied to paper and paperboard as complex mixtures containing reaction products and by-products and unreacted starting materials. This work primarily focussed on the determination of seven perfluorocarboxylic acids (PFCAs) in two commercially available food contact papers: a di-perfluoro-alkyloxy-amino-acid and a perfluoroalkyl phosphate surfactant. In addition, the migration of the PFCAs into five food simulants from two commercial packages was evaluated. All seven PFCAs were detected in the range of 700-2220 µg kg⁻¹ of paper, while three perfluoroalkyl sulphonates were under the LOD. Results from migration tests showed that migration depends on paper characteristics, time and food simulant. The percentage of migration after 10 days at 40°C ranged from 4.8% to 100% for the two papers and different food simulants.

  4. Income Inequality and Migration in Vietnam

    OpenAIRE

    NGUYEN, Tien Dung

    2012-01-01

    In this paper, we have analyzed the recent trends in income inequality, internal and international migrations and investigated the impact of migration on income distribution in Vietnam. Our analysis shows that the effects of migration on income inequality vary with different types of migration, depending on who migrate and where they migrate. Foreign remittances tend to flow toward more affluent households, and they increase income inequality. By contrast, domestic remittances accrue more to ...

  5. Hydrologic modelling of the migration site in the Grimsel rock laboratory -the steady state

    International Nuclear Information System (INIS)

    Herzog, F.

    1989-07-01

    Tracer migration experiments are in progress at the Grimsel Test Site (GTS) in order to test radionuclide transport models and to develop appropriate experimental techniques. In order to assist design and to interpret field tracer tests the knowledge of the hydrology of the site is essential. This report describes the hydraulic modelling efforts with the following objectives: 1) to interpret experimental findings. 2) to provide input, such as flowpaths and flow velocities, for transport modelling. 3) to assist in the design of the tracer experiments. The model concept is based upon the observations, that the fracture, where the migration experiments will take place, is relatively planar, has an average aperture of a few millimeters and is filled with a clayish mateial: The migration fracture is modelled as a two-dimensional, isotropic, heterogeneous equivalent porous medium. To allow for a sufficiently detailed model a hierarchical approach was followed where the boundaries for the 'local' model, i.e. the model in the vicinity of the migration site, were taken by first solving a larger 'regional' model with coarser discretization. Transmissivity values as extracted from single borehole tests were used for definition of the heterogeneous transmissivity field in the model calculations. Model results for hydrostatic pressures and discharge rates compare favourably with experimental data, even though some problems remain to be resolved. Calculations for dipole arrangements have been performed; they turned out to be useful tools for deciding on injection- and withdrawal rates to be applied in the migration experiments as well as for qualitatively estimating tracer recovery rates. (author) 20 figs., 10 tabs., 11 refs

  6. Migration, Narration, Identity

    DEFF Research Database (Denmark)

    Leese, Peter

    (co-editor with Carly McLaughlin and Wladyslaw Witalisz) This book presents articles resulting from joint research on the representations of migration conducted in connection with the Erasmus Intensive Programme entitled «Migration and Narration» taught to groups of international students over...

  7. From migration to settlement: the pathways, migration modes and dynamics of neurons in the developing brain

    Science.gov (United States)

    HATANAKA, Yumiko; ZHU, Yan; TORIGOE, Makio; KITA, Yoshiaki; MURAKAMI, Fujio

    2016-01-01

    Neuronal migration is crucial for the construction of the nervous system. To reach their correct destination, migrating neurons choose pathways using physical substrates and chemical cues of either diffusible or non-diffusible nature. Migrating neurons extend a leading and a trailing process. The leading process, which extends in the direction of migration, determines navigation, in particular when a neuron changes its direction of migration. While most neurons simply migrate radially, certain neurons switch their mode of migration between radial and tangential, with the latter allowing migration to destinations far from the neurons’ site of generation. Consequently, neurons with distinct origins are intermingled, which results in intricate neuronal architectures and connectivities and provides an important basis for higher brain function. The trailing process, in contrast, contributes to the late stage of development by turning into the axon, thus contributing to the formation of neuronal circuits. PMID:26755396

  8. Migrations in Slovenian geography textbooks

    Directory of Open Access Journals (Sweden)

    Jurij Senegačnik

    2013-12-01

    Full Text Available In Slovenia, the migrations are treated in almost all geographical textbooks for different levels of education. In the textbooks for the elementary school from the sixth to ninth grade, students acquire knowledge of the migrations by the inductive approach. Difficulty level of treatment and quantity of information are increasing by the age level. In the grammar school program a trail of gaining knowledge on migration is deductive. Most attention is dedicated to migrations in general geography textbooks. The textbooks for vocational and technical school programs deal with migrations to a lesser extent and with different approaches.

  9. Palaearctic-African Bird Migration

    DEFF Research Database (Denmark)

    Iwajomo, Soladoye Babatola

    Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans-Saharan m......Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans...... of birds from Europe to Africa and opens up the possibility of studying intra-African migration. I have used long-term, standardized autumn ringing data from southeast Sweden to investigate patterns in biometrics, phenology and population trends as inferred from annual trapping totals. In addition, I...... in the population of the species. The papers show that adult and juvenile birds can use different migration strategies depending on time of season and prevailing conditions. Also, the fuel loads of some individuals were theoretically sufficient for a direct flight to important goal area, but whether they do so...

  10. Short-lived, transitory cell-cell interactions foster migration-dependent aggregation.

    Directory of Open Access Journals (Sweden)

    Melissa D Pope

    Full Text Available During embryonic development, motile cells aggregate into cohesive groups, which give rise to tissues and organs. The role of cell migration in regulating aggregation is unclear. The current paradigm for aggregation is based on an equilibrium model of differential cell adhesivity to neighboring cells versus the underlying substratum. In many biological contexts, however, dynamics is critical. Here, we provide evidence that multicellular aggregation dynamics involves both local adhesive interactions and transport by cell migration. Using time-lapse video microscopy, we quantified the duration of cell-cell contacts among migrating cells that collided and adhered to another cell. This lifetime of cell-cell interactions exhibited a monotonic decreasing dependence on substratum adhesivity. Parallel quantitative measurements of cell migration speed revealed that across the tested range of adhesive substrata, the mean time needed for cells to migrate and encounter another cell was greater than the mean adhesion lifetime, suggesting that aggregation dynamics may depend on cell motility instead of the local differential adhesivity of cells. Consistent with this hypothesis, aggregate size exhibited a biphasic dependence on substratum adhesivity, matching the trend we observed for cell migration speed. Our findings suggest a new role for cell motility, alongside differential adhesion, in regulating developmental aggregation events and motivate new design principles for tuning aggregation dynamics in tissue engineering applications.

  11. Migration signatures across the decades: Net migration by age in U.S. counties, 1950-2010

    Directory of Open Access Journals (Sweden)

    Richelle L. Winkler

    2015-05-01

    Full Text Available Background: Migration is the primary population redistribution process in the United States. Selective migration by age, race/ethnic group, and spatial location governs population integration, affects community and economic development, contributes to land use change, and structures service needs. Objective: Delineate historical net migration patterns by age, race/ethnic, and rural-urban dimensions for United States counties. Methods: Net migration rates by age for all US counties are aggregated from 1950−2010, summarized by rural-urban location and compared to explore differential race/ethnic patterns of age-specific net migration over time. Results: We identify distinct age-specific net migration 'signatures' that are consistent over time within county types, but different by rural-urban location and race/ethnic group. There is evidence of moderate population deconcentration and diminished racial segregation between 1990 and 2010. This includes a net outflow of Blacks from large urban core counties to suburban and smaller metropolitan counties, continued Hispanic deconcentration, and a slowdown in White counterurbanization. Conclusions: This paper contributes to a fuller understanding of the complex patterns of migration that have redistributed the U.S. population over the past six decades. It documents the variability in county age-specific net migration patterns both temporally and spatially, as well as the longitudinal consistency in migration signatures among county types and race/ethnic groups.

  12. The Great Migration.

    Science.gov (United States)

    Trotter, Joe William, Jr.

    2002-01-01

    Describes the migration of African Americans in the United States and the reasons why African Americans migrated from the south. Focuses on issues, such as the effect of World War I, the opportunities offered in the north, and the emergence of a black industrial working class. (CMK)

  13. Greater confinement disposal of high activity and special case wastes at the Nevada Test Site: A unified migration assessment approach

    International Nuclear Information System (INIS)

    Davis, P.A.; Olague, N.E.; Johnson, V.L.; Dickman, P.T.; O'Neill, L.J.

    1993-01-01

    The Department of Energy's Nevada Field Office has disposed of a small quantity of high activity and special case wastes using Greater Confinement Disposal facilities in Area 5 of the Nevada Test Site. Because some of these wastes are transuranic radioactive wastes, the Environmental Protection Agency standards for their disposal under 40 CFR Part 191 which requires a compliance assessment. In conducting the 40 CFR Part 191 compliance assessment, review of the Greater Confinement Disposal inventory revealed potentially land disposal restricted hazardous wastes. The regulatory options for disposing of land disposal restricted wastes consist of (1) treatment and monitoring, or (2) developing a no-migration petition. Given that the waste is already buried without treatment, a no-migration petition becomes the primary option. Based on a desire to minimize costs associated with site characterization and performance assessment, a single approach has been developed for assessing compliance with 40 CFR Part 191, DOE Order 5820.2A (which regulates low-level radioactive wastes contained in Greater Confinement Disposal facilities) and developing a no-migration petition. The approach consists of common points of compliance, common time frame for analysis, and common treatment of uncertainty. The procedure calls for conservative bias of modeling assumptions, including model input parameter distributions and adverse processes and events that can occur over the regulatory time frame, coupled with a quantitative treatment of data and parameter uncertainty. This approach provides a basis for a defensible regulatory decision. In addition, the process is iterative between modeling and site characterization activities, where the need for site characterization activities is based on a quantitative definition of the most important and uncertain parameters or assumptions

  14. Studies of nuclear waste migration in geologic media. Annual report, October 1978-September 1979

    International Nuclear Information System (INIS)

    Seitz, M.G.; Rickert, P.G.; Couture, R.A.; Williams, J.; Meldgin, N.; Fried, S.M.; Friedman, A.M.; Steindler, M.J.

    1980-01-01

    Experimental results obtained this year confirm the results obtained in previous years - that nuclides migrating by fluid flow in rock often exhibit complex behavior not predicted by simple chromatographic-type models. A phenomenon found previously to lead to complex behavior for leached radionuclides is that the amount of adsorbed nuclide was not proportional to the nuclide concentration in solution (nonlinear adsorption isotherm). For cesium adsorption on limestone and on basalt, nonlinear isotherms were found this year to occur in the range of cesium concentrations in the groundwater of about 10 -3 to 10 -9 M. Because cesium concentrations in this range can readily be attained by the leaching of solid waste by groundwater, the effects of nonlinear isotherms are germane to nuclide migration. This dependence of cesium migration on the leached concentration of cesium emphasizes the importance of treating the leaching and migration processes simultaneously such as is done in the leach-migration experiments performed in this work. The existence of nonlinear isotherms precludes the use of a single partition coefficient (K/sub d/) to describe cesium migration at an arbitrary cesium concentration above 10 -9 M. Nonetheless, nonlinear isotherms can be studied experimentally (e.g., to give K/sub d/ as a function of concentration) and effects of nonlinear adsorption can be predicted quantitatively. Comparison of results from column and batch tests indicate that, in addition to nonlinear adsorption, kinetic effects need to be considered in predicting nuclide migration from the partition coefficients measured in batch tests. Results of batch experiments of 2 weeks or longer duration pertained to migration expected only at the very lowest (< 50 m/y) groundwater flow rates of interest

  15. Migrating and herniating hydatid cysts

    International Nuclear Information System (INIS)

    Koc, Zafer; Ezer, Ali

    2008-01-01

    Objective: To present the prevalence and imaging findings of patients with hydatid disease (HD) showing features of migration or herniation of the hydatid cysts (HCs) and underline the clinical significance of this condition. Materials and methods: Between May 2003 and June 2006, 212 patients with HD were diagnosed by abdomen and/or thorax CT, searched for migrating or herniating HC. Imaging findings of 7 patients (5 women, 2 men with an age range of 19-63 years; mean ± S.D., 44 ± 19 years) with HD showing transdiaphragmatic migration (6 subjects) or femoral herniation (1 subject) were evaluated. Diagnosis of all the patients were established by pathologic examination and migration or herniation was confirmed by surgery in all patients. Results: Liver HD were identified in 169 (79.7%) of 212 patients with HD. Transdiaphragmatic migration of HCs were identified in 6 (3.5%) of the 169 patients with liver HD. In one patient, femoral herniation of the retroperitoneal HC into the proximal anterior thigh was identified. All of these seven patients exhibiting migration or herniation of HCs had active HCs including 'daughter cysts'. Two patients had previous surgery because of liver HD and any supradiaphragmatic lesion was not noted before operation. Findings of migration or herniation were confirmed by surgery. Conclusion: Active HCs may show migration or herniation due to pressure difference between the anatomic cavities, and in some of the patients, by contribution of gravity. Previous surgery may be a complementary factor for migration as seen in two of our patients. The possibility of migration or herniation in patients with HD should be considered before surgery

  16. Migration in Asia-Europe Relations

    DEFF Research Database (Denmark)

    Juego, Bonn

    2010-01-01

    There is a remarkable difference between viewing migration as a 'social integration' issue, on the one hand, and migration as a 'social relation'. The idea of ‘social integration’ has unrealistic assumptions that see migration as a one-way process, that societies and human relations are static......, and that migrants are mechanical. Policies that are founded on unrealistic assumptions are most likely to generate tensions, conflicts, and contradictions. For a migration process to succeed in forging social harmony and development, it is therefore of decisive and crucial importance to regard migration...... as a ‘social relation’. This is simply because successful migration has to be a harmonious synergy between the migrants (and also the sending countries where they come from) and the receiving society (and its people). As indicated, migrants enter into the receiving society not merely as a passive commodity...

  17. Migration Process Evolution in Europe

    Directory of Open Access Journals (Sweden)

    Carmen Tudorache

    2006-08-01

    Full Text Available The migration phenomenon has always existed, fluctuating by the historic context, the economic, political, social and demographic disparities between the Central and East European countries and the EU Member States, the interdependencies between the origin and receiving countries and the European integration process evolutions. In the European Union, an integrated and inclusive approach of the migration issue is necessary. But a common policy on migration rests an ambitious objective. A common approach of the economic migration management and the harmonization of the migration policies of the Member States represented a challenge for the European Union and will become urgent in the future, especially due to the demographic ageing.

  18. [International migration in the Middle East].

    Science.gov (United States)

    Beauge, G

    1985-01-01

    This special issue contains a selection of 12 papers by various authors on aspects of international migration to the Middle East. Papers are included on the impact of migration on socioeconomic development, income distribution, and rural capitalization in Egypt; migration from rural Lebanon; the effect of emigration on Pakistan; Indian workers in Oman; inter-Arab migration and development; the role of the state in migration in the Arab peninsula; the dynamics of manpower in Kuwait; the Iraqi model and Arab unity; and the impact of this migration on the concept of the New Economic Order.

  19. EMPIRICAL REFLECTIONS ON MIGRATION PHENOMENON. MAJOR EFFECTS OF MIGRATION ON THE HUMAN CAPITAL

    Directory of Open Access Journals (Sweden)

    Simona BUTA

    2013-12-01

    Full Text Available The paper Empirical reflections on migration phenomenon. Major effects of migration on the human capital analyzes the migration flows of the workforce (as part of the human capital globally/regionally, especially the highly qualified workforce migration. The qualified manpower processes of attracting on the work market have not been always well understood and, in some cases, have generated a series of difficulties. This is the reason why we will focus on the „waste of brains” phenomenon, which appears when highly qualified individuals are neither employed in the source-country nor in the target country; and, if they are, their job is below their qualifications.

  20. International migration and the gender

    OpenAIRE

    Koropecká, Markéta

    2010-01-01

    My bachelor thesis explores the connection between international migration and gender. Gender, defined as a social, not a biological term, has a huge impact on the migration process. Statistics and expert studies that have been gender sensitive since 1970s demonstrate that women form half of the amount of the international migrants depending on the world region and representing a wide range of the kinds of international migration: family formation and reunification, labour migration, illegal ...

  1. Cash seeking behaviour and migration: a place-to-place migration function for Cote d'Ivoire.

    Science.gov (United States)

    Velenchik, A D

    1993-12-01

    "This paper presents estimates of an aggregate place-to-place migration function for Cote d'Ivoire based on the premise that migration is motivated by rural residents' desire for cash income. The results indicate that migration from a region responds differently to changes in cash and food income, which supports the idea that it is the composition of rural income, and not just its level, that determines migration flows." excerpt

  2. SOFTWARE IMPLEMENTATION FOR SCORM CONTENT MIGRATION IN THE LEARNING MANAGEMENT SYSTEM

    Directory of Open Access Journals (Sweden)

    Y. B. Popova

    2017-01-01

    Full Text Available Using of learning management systems increases the possibility of teachers and students in achieving their goals in education. Such systems provide learning content, help to organize and to monitor training progress, help to collect statistics. However, the transition from one LMS to another there is a problem of content migration, because all training materials and tests should either be recreated, or somehow be migrated to the new system. Content migration by hand is a very time-consuming process, so the leading developers of the learning management systems developed a standard for the organization and storage of content, called SCORM (Eng., Sharable Content Object Reference Model. Created by this standard, the content must migrate to the learning management system provided its support for these systems. SCORM standard allows you to create training content that is not dependent on the learning management system, but the loosely embedded in it. This approach enables teachers to develop unique courses and put them free available or for sale in the Internet for all interested persons, and to use educational content created by the best specialists around the world to carry out their activities. The content on the SCORM standard imposes certain requirements on the learning management systems, as they do not distort the training content and properly interact with the tests. The aim of this article is a software implementation of a content migration by SCORM standard from other learning management systems in its own development used at the Software Department of the Faculty of Information Technology and Robotics of the Belarusian National Technical University.

  3. The radionuclide migration experiment - overview of investigations 1985 - 1990

    International Nuclear Information System (INIS)

    Frick, U.; McKinley, I.G.; Baeyens, B.; Bradbury, M.H.; Eikenberg, J.; Heer, W.; Hoehn, E.; Smith, P.A.; Alexander, W.R.; Bossart, P.; Buehler, C.; Fierz, T.

    1992-03-01

    This paper provides an overview of the investigations conducted from 1985 to 1990 as a part of the radionuclide migration experiment which is currently in progress in the Nagra underground research laboratory at the Grimsel pass in the Central Swiss Alps. The major aims of the project are (1) to test the extrapolation of laboratory sorption data to field conditions, (2) to analyse retardation processes in a fractured rock, (3) to improve and develop the necessary methodologies for site characterization and (4) to test existing geochemical, hydrodynamic, and solute transport models or their associated data bases. Field and modeling work are complemented by an extensive laboratory support programme. The Grimsel migration experiment demonstrates conclusively how the combined efforts of modeling, laboratory and field investigations can substantially widen the understanding of radionuclide transport in a geological environment. (author) figs., tabs., refs

  4. Long-term gas migration modelling in compacted bentonite using swelling/shrinkage-dependent two phase flow parameters

    International Nuclear Information System (INIS)

    Tawara, Y.; Mori, K.; Tada, K.; Shimura, T.; Sato, S.; Yamamoto, S.; Asano, H.; Namiki, K.

    2012-01-01

    Document available in extended abstract form only. After the completion of field-scaled Gas Migration Test (GMT) at the Grimsel Test Site (GTS Phase V Project, 1996-2004), an advanced gas migration modelling study has been implemented to increase the accuracy and reliability as a part of the R and D programs by the Radioactive Waste Management funding and research Center (RWMC) in Japan. The multiple gas migration modes which consist of diffusive transport of dissolved gas, conventional two phase flow, pore failure induced microscopic fissuring and macroscopic fracturing flow, were identified in GMT bentonite. However the required parameters and constitutive models governing those modes are still uncertain. To tackle this issue, an extended validation and scoping study aiming to generalize such gas migration behavior has been performed in the advanced gas migration modelling study. One of the main objectives of the validation study is to identify gas migration modes using laboratory test data and to qualify the alternative models and parameters. In the scoping study, we have extracted the specific THMC (Thermal, Hydrological, Mechanical and Chemical) coupled processes which have impacts on the performance measures such as the pressure built-up in EBS (Engineered Barrier System) and expelled water to the geosphere by gas generation and transport. The measured data of hydration tests and gas injection tests using bentonite specimens with different water contents were reproduced. Two phase flow parameters were estimated using the observed data of both types of tests, independently. The simulated results of the conventional two phase flow model were well-matched with the hydration test data. In the gas injection test, the extended two phase flow model which simulates the pressure-induced pore failure (pathway dilation), was able to reproduce observed data reasonably. However, we found that the identified parameters obtained from the hydration test data were

  5. Mixed and Complex Mixed Migration during Armed Conflict: Multidimensional Empirical Evidence from Nepal.

    Science.gov (United States)

    Williams, Nathalie E

    Historically, legal, policy, and academic communities largely ascribed to a dichotomy between forced and voluntary migration, creating a black and white vision that was convenient for legal and policy purposes. More recently, discussions have begun addressing the possibility of mixed migration, acknowledging that there is likely a wide continuum between forced and voluntary, and most migrants likely move with some amount of compulsion and some volition, even during armed conflict. While the mixed migration hypothesis is well-received, empirical evidence is disparate and somewhat blunt at this point. In this article, I contribute a direct theoretical and causal pathway discussion of mixed migration. I also propose the complex mixed migration hypothesis, which argues that not only do non-conflict related factors influence migration during conflict, but they do so differently than during periods of relative peace. I empirically test both hypotheses in the context of the recent armed conflict in Nepal. Using detailed survey data and event history models, results provide strong evidence for both mixed migration and complex mixed migration during conflict hypotheses. These hypotheses and evidence suggest that armed conflict might have substantial impacts on long-term population growth and change, with significant relevance in both academic and policy spheres.

  6. Samtidskunst og migration

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    2010-01-01

    "Samtidskunst og migration. En oversigt over faglitteraturen" er en forskningsoversigt der gør status over hvad der hidtil er skrevet inden for det kunsthistoriske område om vor tids billedkunst og migration som politisk, socialt og kulturelt fænomen, primært i forbindelse med immigration til...

  7. Detection and toxicity assessment of nitrosamines migration from latex gloves in the Chinese market.

    Science.gov (United States)

    Feng, Di; Wang, Huiping; Cheng, Xuelian; Wang, Jiedong; Ning, Lifeng; Zhou, Qingfeng; Zhou, Yue; Yang, Quanli

    2009-09-01

    Nitrosamines are potent carcinogens and have been found in latex products. In 2007, twenty-seven natural latex gloves including sterile gloves, examination gloves and household use gloves were sampled from the Chinese market. This study monitored the migration of nitrosamines and nitrosatable substance from these gloves, and evaluated their mutagenicity using a Salmonella typhimurium mutation assay (Ames assay) with the strains TA98, TA97, TA100 and TA102 and by a micronucleus test (MN test) using ICR mice. In addition, the cytotoxicity of these compounds was determined by a MTT assay. N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA) and N-nitrosodibutylamine (NDBA) were all found in samples treated with artificial sweat for 4h at 37 degrees C, and total nitrosamines varied from 18.89 to 244.51microg/Kg. The nitrosamine mixture of NDMA, NDEA and NDBA was used in both the Ames assay and the MN test. The proportion of NDMA, NDEA and NDBA (1:10:20) was selected according to the proportion of nitrosamines migration from sample E05. In the Ames assay, the lowest dose (1.98 x 10(-3)microg per plate) produced a positive result in the TA98 strain, corresponding to nitrosamines migration from sample E05 of 0.016g (the total nitrosamines migration from glove E05 was 122.55 microg/kg). The TA100 strain responded positively at a dose of 4.96 x 10(-2)microg per plate, corresponding to nitrosamines migration from glove E05 of 0.040g. The MN test showed nitrosamine migration of 3.04 mg from 2066 pairs of sample E05 and could induce micronuclei in one mouse weighing 28g (average weight of one E05 glove was 6g). Extracts from gloves were found to be cytotoxic and there was a significant correlation between cytotoxicity (IC50) and the release level of nitrosamines. In conclusion, in view of the high content of nitrosamines in latex gloves and the potential toxicity of nitrosamines migration from these gloves, it is suggested that both an effective and feasible detection

  8. RSA migration of total knee replacements.

    Science.gov (United States)

    Pijls, Bart G; Plevier, José W M; Nelissen, Rob G H H

    2018-06-01

    Purpose - We performed a systematic review and meta-analyses to evaluate the early and long-term migration patterns of tibial components of TKR of all known RSA studies. Methods - Migration pattern was defined as at least 2 postoperative RSA follow-up moments. Maximal total point motion (MTPM) at 6 weeks, 3 months, 6 months, 1 year, 2 years, 5 years, and 10 years were considered. Results - The literature search yielded 1,167 hits of which 53 studies were included, comprising 111 study groups and 2,470 knees. The majority of the early migration occurred in the first 6 months postoperatively followed by a period of stability, i.e., no or very little migration. Cemented and uncemented tibial components had different migration patterns. For cemented tibial components there was no difference in migration between all-poly and metal-backed components, between mobile bearing and fixed bearing, between cruciate retaining and posterior stabilized. Furthermore, no difference existed between TKR measured with model-based RSA or marker-based RSA methods. For uncemented TKR there was some variation in migration with the highest migration for uncoated TKR. Interpretation - The results from this meta-analysis on RSA migration of TKR are in line with both the survival analyses results from joint registries of these TKRs as well as revision rates results from meta-analyses, thus providing further proof for the association between early migration and late revision for loosening. The pooled migration patterns can be used both as benchmarks and for defining migration thresholds for future evaluation of new TKR.

  9. Current Migration Movements in Europe

    Directory of Open Access Journals (Sweden)

    Jelena Zlatković Winter

    2004-09-01

    Full Text Available After a brief historical review of migrations in Europe, the paper focuses on current migration trends and their consequences. At the end of the 1950s, Western Europe began to recruit labour from several Mediterranean countries – Italy, Spain, Portugal and former Yugoslavia, and later from Morocco, Algeria, Tunisia and Turkey. Some countries, such as France, Great Britain and the Netherlands, recruited also workers from their former colonies. In 1970 Germany had the highest absolute number of foreigners, followed by France, and then Switzerland and Belgium. The total number of immigrants in Western Europe was twelve million. During the 1970s mass recruitment of foreign workers was abandoned, and only the arrival of their family members was permitted, which led to family reunification in the countries of employment. Europe closed its borders, with the result that clandestine migration increased. The year 1989 was a turning point in the history of international migrations. The political changes in Central and Eastern Europe brought about mass migration to the West, which culminated in the so-called “mass movement of 1989–1990”. The arrival of ethnic Germans in Germany, migration inside and outside of the territory of the former Soviet Union, an increase in the number of asylum seekers and displaced persons, due to armed conflicts, are – according to the author – the main traits of current migration. The main part of the paper discusses the causes and effects of this mass wave, as well as trends in labour migration, which is still present. The second part of the paper, after presenting a typology of migrations, deals with the complex processes that brought about the formation of new communities and led to the phenomenon of new ethnic minorities and to corresponding migration policies in Western European countries that had to address these issues.

  10. The Transformative Forces of Migration: Refugees and the Re-Configuration of Migration Societies

    Directory of Open Access Journals (Sweden)

    Ulrike Hamann

    2018-03-01

    Full Text Available In this thematic issue, we attempt to show how migrations transform societies at the local and micro level by focusing on how migrants and refugees navigate within different migration regimes. We pay particular attention to the specific formation of the migration regimes that these countries adopt, which structure the conditions of the economic, racialised, gendered, and sexualized violence and exploitation during migration processes. This interactive process of social transformation shapes individual experiences while also being shaped by them. We aim to contribute to the most recent and challenging question of what kind of political and social changes can be observed and how to frame these changes theoretically if we look at local levels while focusing on struggles for recognition, rights, and urban space. We bring in a cross-country comparative perspective, ranging from Canada, Chile, Spain, Sweden, Turkey, and to Germany in order to lay out similarities and differences in each case, within which our authors analyse these transformative forces of migration.

  11. Globalization, Migration and Development

    Directory of Open Access Journals (Sweden)

    George, Susan

    2002-01-01

    Full Text Available EnglishMigration may become the most important branch of demography in the earlydecades of the new millennium in a rapidly globalizing world. This paper discusses the causes, costsand benefits of international migration to countries of the South and North, and key issues of commonconcern. International migration is as old as national boundaries, though its nature, volume,direction, causes and consequences have changed. The causes of migration are rooted in the rate ofpopulation growth and the proportion of youth in the population, their education and training,employment opportunities, income differentials in society, communication and transportationfacilities, political freedom and human rights and level of urbanization. Migration benefits the Souththrough remittances of migrants, improves the economic welfare of the population (particularly womenof South countries generally, increases investment, and leads to structural changes in the economy.However, emigration from the South has costs too, be they social or caused by factors such as braindrain. The North also benefits by migration through enhancement of economic growth, development ofnatural resources, improved employment prospects, social development and through exposure toimmigrants' new cultures and lifestyles. Migration also has costs to the North such as of immigrantintegration, a certain amount of destabilization of the economy, illegal immigration, and socialproblems of discrimination and exploitation. Issues common to both North and South include impact onprivate investment, trade, international cooperation, and sustainable development. Both North andSouth face a dilemma in seeking an appropriate balance between importing South's labour or itsproducts and exporting capital and technology from the North.FrenchLa migration est sans doute devenue la partie la plus importante de la démographie des premières décennies du nouveau millénaire dans un monde qui change rapidement. Ce

  12. Lead migration from toys by anodic stripping voltammetry using a bismuth film electrode.

    Science.gov (United States)

    Leal, M Fernanda C; Catarino, Rita I L; Pimenta, Adriana M; Souto, M Renata S; Afonso, Christelle S; Fernandes, Ana F Q

    2016-09-02

    Metals may be released from toys via saliva during mouthing, via sweat during dermal contact, or via gastric and intestinal fluids after partial or whole ingestion. In this study, we determined the lead migration from toys bought on the Portuguese market for children below 3 years of age. The lead migration was performed according to the European Committee for Standardization EN 71-3, which proposes a 2-hour migration test that simulates human gastric conditions. The voltammetric determination of migrated lead was performed by anodic stripping voltammetry (ASV) at a bismuth film electrode (BiFE). For all the analyzed toys, the values of migrated lead did not exceed the limits imposed by the European Committee for Standardization EN 71-3 (90 mg kg -1 ) and by the EU Directive 2009/48/EC (13.5 mg kg -1 ) on the safety of toys.

  13. MIGRATION IMPACT ON ECONOMICAL SITUATION

    Directory of Open Access Journals (Sweden)

    Virginia COJOCARU

    2016-01-01

    Full Text Available This paper presents recent trends and flows of labor migration and its impact on economic and social life. Main aim of this research sets up the influence of the migration on the European economics and its competitiveness. Methods of research are: method of comparison, analysis method, method of deduction, method of statistics, modeling method. The economic impact of migration has been intensively studied but is still often driven by ill-informed perceptions, which, in turn, can lead to public antagonism towards migration. These negative views risk jeopardising efforts to adapt migration policies to the new economic and demographic challenges facing many countries. Migration Policy looks at the evidence for how immigrants affect the economy in three main areas: The labour market, public purse and economic growth. In Europe, the scope of labour mobility greatly increased within the EU/EFTA zones following the EU enlargements of 2004, 2007 and 2014-2015. This added to labour markets’ adjustment capacity. Recent estimates suggest that as much as a quarter of the asymmetric labour market shock – that is occurring at different times and with different intensities across countries – may have been absorbed by migration within a year.

  14. Role of leucocytes cell population data in the early detection of sepsis.

    Science.gov (United States)

    Urrechaga, Eloísa; Bóveda, Oihane; Aguirre, Urko

    2018-03-01

    The cell population data (CPD) parameters reported by XN analyser (Sysmex, Kobe, Japan) reflect the size and internal structure of leucocytes. We aimed to assess the clinical utility of these parameters as biomarkers for the early diagnosis of sepsis. The study group (G1) included 586 controls (no quantitative or morphological alterations in the complete blood count) and 137 patients diagnosed with sepsis. The reliability of the model was evaluated using a validation group (G2) of 212 controls and 60 patients with sepsis. The optimal cut-off for the diagnosis of sepsis and the OR for CPD were established using a univariate logistic regression. A multivariate logistic regression model was then created. The OR and area under the curve were recorded. A risk stratification scale (neutrophils and monocytes (NEMO)) for diagnosing sepsis was established on the basis of the coefficients of the multivariate model. MO-X and neutrophils fluorescence intensity (NE-SFL) were found to be the most relevant of the CPD in predicting sepsis applying multivariate analysis to G1.NEMO score was composed using the above-mentioned CPD and subsequently stratified into three risk groups: mild (≤3), moderate (4≤NEMO≤5) and high (≥6). The OR for patients with a score of 4-5 was 10 and 249 for a score of ≥6. When applied to G2, the positive predictive value was 84.8 % and the negative predictive value was 96.0%. CPD are potentially useful for the early diagnosis of sepsis. Their values were used to compose in NEMO score can help in rapid and reliable decision making. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  15. /sup 111/In autologous leucocytes in the diagnosis and assessment of inflammatory bowel disease. [Tropolone

    Energy Technology Data Exchange (ETDEWEB)

    Saverymuttu, S.H.; Peters, A.M.; Chadwick, V.S.; Hodgson, H.J.; Lavender, J.P. (Hammersmith Hospital, London (UK))

    1982-01-01

    Indium-111 autologous leukocyte scanning is now established as an effective method of localising sepsis (Ascher and others, 1980). In view of the extensive leucocyte infiltration of the intestinal wall in inflammatory bowel disease, the authors have prospectively studied the use of indium-111 labelled white cells in a variety of inflammatory bowel disorders. Leukocytes were labelled in 68 patients using /sup 111/In acetylacetonate and in 18 patients /sup 111/In tropolone. Crude mixed leukocytes preparations were used in 74 patients and pure neutrophil preparation used in 12 patients. Gamma scans over the abdomen were performed from 40 min later after re-injection of the labelled cells and assessed. /sup 111/In-tropolone labelling appeared to offer the advantage over /sup 111/In-acac labelling in localising inflamed bowel earlier. The technique of /sup 111/In-leukocyte scanning offers several advantages over the alternative technique of imaging diseased bowel using gallium-67 citrate. Indium-111 leukocyte scanning provides a novel approach to the problem of diagnosis and assessment of inflammatory bowel disease. It is non-invasive, requires no bowel preparation and this is safe in the acutely sick patient where conventional radiological imaging methods may be hazardous. /sup 111/In faecal excretion provides an objective assessment of disease activity which should prove useful in evaluating treatment regimes.

  16. Modelling the Grimsel migration field experiments at PSI

    International Nuclear Information System (INIS)

    Heer, W.

    1997-01-01

    For several years tracer migration experiments have been performed at Nagra's Grimsel Test Site as a joint undertaking of Nagra, PNC and PSI. The aims of modelling the migration experiments are (1) to better understand the nuclide transport through crystalline rock; (2) to gain information on validity of methods and correlating parameters; (3) to improve models for safety assessments. The PSI modelling results, presented here, show a consistent picture for the investigated tracers (the non-sorbing uranine, the weakly sorbing sodium, the moderately sorbing strontium and the more strongly sorbing cesium). They represent an important step in building up confidence in safety assessments for radioactive waste repositories. (author) 5 figs., 1 tab., 12 refs

  17. Multisource Least-squares Reverse Time Migration

    KAUST Repository

    Dai, Wei

    2012-12-01

    Least-squares migration has been shown to be able to produce high quality migration images, but its computational cost is considered to be too high for practical imaging. In this dissertation, a multisource least-squares reverse time migration algorithm (LSRTM) is proposed to increase by up to 10 times the computational efficiency by utilizing the blended sources processing technique. There are three main chapters in this dissertation. In Chapter 2, the multisource LSRTM algorithm is implemented with random time-shift and random source polarity encoding functions. Numerical tests on the 2D HESS VTI data show that the multisource LSRTM algorithm suppresses migration artifacts, balances the amplitudes, improves image resolution, and reduces crosstalk noise associated with the blended shot gathers. For this example, multisource LSRTM is about three times faster than the conventional RTM method. For the 3D example of the SEG/EAGE salt model, with comparable computational cost, multisource LSRTM produces images with more accurate amplitudes, better spatial resolution, and fewer migration artifacts compared to conventional RTM. The empirical results suggest that the multisource LSRTM can produce more accurate reflectivity images than conventional RTM does with similar or less computational cost. The caveat is that LSRTM image is sensitive to large errors in the migration velocity model. In Chapter 3, the multisource LSRTM algorithm is implemented with frequency selection encoding strategy and applied to marine streamer data, for which traditional random encoding functions are not applicable. The frequency-selection encoding functions are delta functions in the frequency domain, so that all the encoded shots have unique non-overlapping frequency content. Therefore, the receivers can distinguish the wavefield from each shot according to the frequencies. With the frequency-selection encoding method, the computational efficiency of LSRTM is increased so that its cost is

  18. Migration processes in SCO member states

    Directory of Open Access Journals (Sweden)

    Valentina Sergeevna Antonyuk

    2012-12-01

    Full Text Available The article concerns modern state and development of migration processes in SCO member states. As a main method of research statistical analysis was applied. The article shows that migration streams between SCO member states are rather intensive, and the problem of labor migration becomes more and more urgent. The countries of consuming and supplying of labour force are clearly differentiated in the region. For some countries, labor export is the key sector of economy. At the same time, interstate relations between SCO member states sometimes are rather disputed. The most urgent factors causing the development of migration processes in the region were determined. Among them, thefactor of growing outflows from China isespecially noted. It is noted that migration processes are discussed by SCO member states nowadays in terms of illegal migration and international criminality connected with it. It means that the question of labor migration is a real problem. It is indicated that the creation of a specific joint commission on migration policy affiliated with the Council of Foreign Ministers of SCO member states is the necessary condition of effective interaction in migration questions within the framework of Shanghai Cooperation Organization.

  19. The mechanism for primordial germ-cell migration is conserved between Japanese eel and zebrafish.

    Directory of Open Access Journals (Sweden)

    Taiju Saito

    Full Text Available Primordial germ cells (PGCs are segregated and specified from somatic cells during early development. These cells arise elsewhere and have to migrate across the embryo to reach developing gonadal precursors. Several molecules associated with PGC migration (i.e. dead-end, nanos1, and cxcr4 are highly conserved across phylum boundaries. However, since cell migration is a complicated process that is regulated spatially and temporally by multiple adaptors and signal effectors, the process is unlikely to be explained by these known genes only. Indeed, it has been shown that there are variations in PGC migration pattern during development among teleost species. However, it is still unclear whether the actual mechanism of PGC migration is conserved among species. In this study, we studied the migration of PGCs in Japanese eel (Anguilla japonica embryos and tested the migration mechanism between Japanese eel and zebrafish (Danio rerio for conservation, by transplanting eel PGCs into zebrafish embryos. The experiments showed that eel PGCs can migrate toward the gonadal region of zebrafish embryos along with endogenous PGCs, even though the migration patterns, behaviors, and settlements of PGCs are somewhat different between these species. Our results demonstrate that the migration mechanism of PGCs during embryonic development is highly conserved between these two distantly related species (belonging to different teleost orders.

  20. Automated seismic waveform location using Multichannel Coherency Migration (MCM)-I. Theory

    Science.gov (United States)

    Shi, Peidong; Angus, Doug; Rost, Sebastian; Nowacki, Andy; Yuan, Sanyi

    2018-03-01

    With the proliferation of dense seismic networks sampling the full seismic wavefield, recorded seismic data volumes are getting bigger and automated analysis tools to locate seismic events are essential. Here, we propose a novel Multichannel Coherency Migration (MCM) method to locate earthquakes in continuous seismic data and reveal the location and origin time of seismic events directly from recorded waveforms. By continuously calculating the coherency between waveforms from different receiver pairs, MCM greatly expands the available information which can be used for event location. MCM does not require phase picking or phase identification, which allows fully automated waveform analysis. By migrating the coherency between waveforms, MCM leads to improved source energy focusing. We have tested and compared MCM to other migration-based methods in noise-free and noisy synthetic data. The tests and analysis show that MCM is noise resistant and can achieve more accurate results compared with other migration-based methods. MCM is able to suppress strong interference from other seismic sources occurring at a similar time and location. It can be used with arbitrary 3D velocity models and is able to obtain reasonable location results with smooth but inaccurate velocity models. MCM exhibits excellent location performance and can be easily parallelized giving it large potential to be developed as a real-time location method for very large datasets.

  1. Pre-migration persecution, post-migration stressors and resources, and post-migration mental health: A study of severely traumatized U.S. Arab immigrant women

    Science.gov (United States)

    Norris, Anne E.; Aroian, Karen J.; Nickerson, David

    2015-01-01

    Background Competing theories exist regarding the importance of pre-migration trauma as compared to post-migration stressors and resources with respect to the risk to immigrant mental health. Objective To examine how type of pre-migration trauma, post-migration stressors, and post-migration resources differentially predict PTSD and MDD symptomatology in Arab immigrant women who have been exposed to pre-migration trauma. Design Descriptive; using multinomial logistic regression to explain membership in one of four groups: (a) PTSD only (n = 14); (b) major depressive disorder (MDD) (n = 162), (c) Co-Morbid PTSD-MDD (n = 148), (d) Subclinical Symptoms (n = 209). Results Post-immigration related stressors (as measured by the Demands of Immigration (DI)) had the strongest effect: Parameter estimates indicated that a unit increase in DI scores was associated with a nearly 17 fold increase in the likelihood of being in the Co-morbid relative to the Subclinical group, and a nearly 2.5 increase in the likelihood of being in the Co-Morbid relative to the MDD only group (p Arab immigrant women for depression and PTSD is important given high levels observed in this community based sample. PMID:21835819

  2. Migrations of theory, method and practice: a reflection on themes in migration studies (Review article)

    OpenAIRE

    Palmary, Ingrid

    2009-01-01

    In this review article, I offer some reflection on three themes in migration research, namely, the categorisation and quantification of migration, the role of trauma and distress in such categorisation, and the feminisation of migration. I was prompted to explore these three themes after reading a recent publication on migration in southern Africa (edited by Kok, Gelderblom, Oucho and Van Zyl, 2006). In this paper I raise these as three areas that appear to be determining the boundaries of th...

  3. The Meta-Pragmatic Discourses of Australian High School Students on Language, Migration and Belonging

    Science.gov (United States)

    Starks, Donna; Willoughby, Louisa

    2015-01-01

    Recent years have seen a backlash against multiculturalism in many Western countries and increasing calls to restrict migration and citizenship rights to those who can pass language tests. This paper explores the sentiment of high school students who were born and raised in Australia towards issues of language and migration, including the need for…

  4. College Student Migration.

    Science.gov (United States)

    Fenske, Robert H.; And Others

    This study examines the background characteristics of two large national samples of first-time enrolled freshmen who (a) attended college within their state of residence but away from their home community, (b) migrated to a college in an adjacent state, (c) migrated to a college in a distant state, and (d) attended college in their home community.…

  5. Role of particulates in subsurface migration of wastes

    International Nuclear Information System (INIS)

    Eichholz, G.G.; Craft, T.F.

    1982-01-01

    In contrast to the usual assumption that migration of radioactive wastes from deep repositories will occur primarily in the form of dissolved ions, subject to control by ion-exchange phenomena on exposed surfaces, an alternative mode of migration has been investigated by way of submicron-size suspended particles that act as carriers for leached waste atoms and travel relatively freely through water-bearing strata. Measurements have been conducted on adsorption on kaolin of Pu, Tc, Cs, Np and other tracer ions, with results strongly dependent on the nature of the water and its pH. Independently, column tests have been performed to study the movement of labelled kaolin suspensions through beds of sand, basalt, limestone and shale. For each medium, filter coefficients and sorption coefficients have been determined. For some bed materials the effluent suspensions displayed a prompt and a delayed component; the nature of the delay mechanism is not clearly understood at present. The investigations have shown that under certain conditions particulate migration may constitute a competitive pathway for waste motion. (author)

  6. Attenuation compensation for least-squares reverse time migration using the viscoacoustic-wave equation

    KAUST Repository

    Dutta, Gaurav

    2014-10-01

    Strong subsurface attenuation leads to distortion of amplitudes and phases of seismic waves propagating inside the earth. Conventional acoustic reverse time migration (RTM) and least-squares reverse time migration (LSRTM) do not account for this distortion, which can lead to defocusing of migration images in highly attenuative geologic environments. To correct for this distortion, we used a linearized inversion method, denoted as Qp-LSRTM. During the leastsquares iterations, we used a linearized viscoacoustic modeling operator for forward modeling. The adjoint equations were derived using the adjoint-state method for back propagating the residual wavefields. The merit of this approach compared with conventional RTM and LSRTM was that Qp-LSRTM compensated for the amplitude loss due to attenuation and could produce images with better balanced amplitudes and more resolution below highly attenuative layers. Numerical tests on synthetic and field data illustrated the advantages of Qp-LSRTM over RTM and LSRTM when the recorded data had strong attenuation effects. Similar to standard LSRTM, the sensitivity tests for background velocity and Qp errors revealed that the liability of this method is the requirement for smooth and accurate migration velocity and attenuation models.

  7. Attenuation compensation for least-squares reverse time migration using the viscoacoustic-wave equation

    KAUST Repository

    Dutta, Gaurav; Schuster, Gerard T.

    2014-01-01

    Strong subsurface attenuation leads to distortion of amplitudes and phases of seismic waves propagating inside the earth. Conventional acoustic reverse time migration (RTM) and least-squares reverse time migration (LSRTM) do not account for this distortion, which can lead to defocusing of migration images in highly attenuative geologic environments. To correct for this distortion, we used a linearized inversion method, denoted as Qp-LSRTM. During the leastsquares iterations, we used a linearized viscoacoustic modeling operator for forward modeling. The adjoint equations were derived using the adjoint-state method for back propagating the residual wavefields. The merit of this approach compared with conventional RTM and LSRTM was that Qp-LSRTM compensated for the amplitude loss due to attenuation and could produce images with better balanced amplitudes and more resolution below highly attenuative layers. Numerical tests on synthetic and field data illustrated the advantages of Qp-LSRTM over RTM and LSRTM when the recorded data had strong attenuation effects. Similar to standard LSRTM, the sensitivity tests for background velocity and Qp errors revealed that the liability of this method is the requirement for smooth and accurate migration velocity and attenuation models.

  8. Brine migration test performed in the older Halite Na2β formation at the Asse salt mine. Temperature-test field No4(TTF4)

    International Nuclear Information System (INIS)

    Rothfuchs, T.; Schwarzianek, P.; Feddersen, H.

    1984-01-01

    A so-called brine migration test was performed in the Older Halite Na2β formation at the Asse salt mine. The test was designed to investigate the rate of thermally induced brine or crystalline water release into a heated borehole. The heat source simulates heat-producing high level radioactive waste. As a heat source a heater of 5,4 m length and 200 mm diameter was used in a 15 m deep vertical borehole. The initial heater power was 9000 Watt. Due to corrosion the heater power decreased during the experiment. The following measuring results were obtained: maximum salt temperature on heating day 137 = 280 0 C; average temperature gradient at the borehole wall on heating day 137 = 49 0 C/7,5 cm; accumulated water release on heating day 688 = 3386 g; pH-value of the condensate in the cool trap = 3; analysis of the borehole atmosphere: - no Cl 2 , SO 2 , HCl, H 2 S; - O 2 max 4%, CO max 0,3%, CO 2 max 12% and CH 4 max 1,3%. In addition to the investigation of the borehole atmosphere measurements of the local principle stresses and of the rock deformations were performed

  9. National and international graduate migration flows.

    Science.gov (United States)

    Mosca, Irene; Wright, Robert E

    2010-01-01

    This article examines the nature of national and international graduate migration flows in the UK. Migration equations are estimated with microdata from a matched dataset of Students and Destinations of Leavers from Higher Education, information collected by the Higher Education Statistical Agency. The probability of migrating is related to a set of observable characteristics using multinomial logit regression. The analysis suggests that migration is a selective process with graduates with certain characteristics having considerably higher probabilities of migrating, both to other regions of the UK and abroad.

  10. Nuss bar migrations: occurrence and classification

    International Nuclear Information System (INIS)

    Binkovitz, Lauren E.; Binkovitz, Larry A.; Zendejas, Benjamin; Moir, Christopher R.

    2016-01-01

    Pectus excavatum results from dorsal deviation of the sternum causing narrowing of the anterior-posterior diameter of the chest. It can result in significant cosmetic deformities and cardiopulmonary compromise if severe. The Nuss procedure is a minimally invasive technique that involves placing a thin horizontally oriented metal bar below the dorsal sternal apex for correction of the pectus deformity. To identify the frequency and types of Nuss bar migrations, to present a new categorization of bar migrations, and to present examples of true migrations and pseudomigrations. We retrospectively reviewed the electronic medical records and all pertinent radiologic studies of 311 pediatric patients who underwent a Nuss procedure. We evaluated the frequency and type of bar migrations. Bar migration was demonstrated in 23 of 311 patients (7%) and occurred within a mean period of 26 days after surgery. Bar migrations were subjectively defined as deviation of the bar from the position demonstrated on the immediate postoperative radiographs and categorized as superior, inferior, rotation, lateral or flipped using a new classification system. Sixteen of the 23 migrations required re-operation. Nuss bar migration can be diagnosed with careful evaluation of serial radiographs. Nuss bar migration has a wide variety of appearances and requires exclusion of pseudomigration resulting from changes in patient positioning between radiologic examinations. (orig.)

  11. Nuss bar migrations: occurrence and classification

    Energy Technology Data Exchange (ETDEWEB)

    Binkovitz, Lauren E.; Binkovitz, Larry A. [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Zendejas, Benjamin; Moir, Christopher R. [Mayo Clinic, Department of Surgery, Rochester, MN (United States)

    2016-12-15

    Pectus excavatum results from dorsal deviation of the sternum causing narrowing of the anterior-posterior diameter of the chest. It can result in significant cosmetic deformities and cardiopulmonary compromise if severe. The Nuss procedure is a minimally invasive technique that involves placing a thin horizontally oriented metal bar below the dorsal sternal apex for correction of the pectus deformity. To identify the frequency and types of Nuss bar migrations, to present a new categorization of bar migrations, and to present examples of true migrations and pseudomigrations. We retrospectively reviewed the electronic medical records and all pertinent radiologic studies of 311 pediatric patients who underwent a Nuss procedure. We evaluated the frequency and type of bar migrations. Bar migration was demonstrated in 23 of 311 patients (7%) and occurred within a mean period of 26 days after surgery. Bar migrations were subjectively defined as deviation of the bar from the position demonstrated on the immediate postoperative radiographs and categorized as superior, inferior, rotation, lateral or flipped using a new classification system. Sixteen of the 23 migrations required re-operation. Nuss bar migration can be diagnosed with careful evaluation of serial radiographs. Nuss bar migration has a wide variety of appearances and requires exclusion of pseudomigration resulting from changes in patient positioning between radiologic examinations. (orig.)

  12. Magnetic Field Fluctuations Due to Diel Vertical Migrations of Zooplankton

    Science.gov (United States)

    Dean, C.; Soloviev, A.

    2016-12-01

    Dean et al. (2016) have indicated that at high zooplankton concentrations, diel vertical migrations (DVM) cause velocity fluctuations and a respective increase of the dissipation rate of turbulent kinetic energy (TKE). In this work, we used a 3D non-hydrostatic computational fluid dynamics model with Lagrangian particle injections (a proxy for migrating organisms) via a discrete phase model to simulate the effect of turbulence generation by DVM. We tested a range of organism concentrations from 1000 to 10,000 organisms/m3. The simulation at an extreme concentration of zooplankton showed an increase in dissipation rate of TKE by two to three orders of magnitude during DVM over background turbulence, 10-8 W kg-1. At lower concentrations (Frank, J. Wood, 2016: Biomixing due to diel vertical migrations of zooplankton. Ocean Modelling 98, 51-64.

  13. Hydrology and Radionuclide Migration Program, 1985--1986 progress report

    International Nuclear Information System (INIS)

    Buddemeier, R.W.

    1988-09-01

    This report presents results from the Lawrence Livermore National Laboratory's participation in the Hydrology and Radionuclide Migration Program (formerly the Radionuclide Migration Project) at the Nevada Test Site (NTS) during fiscal years 1985 and 1986. The report discusses studies of the partitioning and movement of dissolved and colloidal radionuclides at the Cheshire (U20n) site; tracer studies of shallow recharge and of plant-water uptake at the Cambric-site ditch carrying the effluent water pumped from well RNM-2; development of a rapid and sensitive assay for 99 Tc in groundwater and its application to a survey of technetium activities at a variety of test wells; and a series of methodological studies directed toward calibration, understanding, and improving our low-level radionuclide determinations. Groundwater sampled from the Cheshire cavity and from adjacent aquifers contains substantial concentrations (mg/L) of colloids that appear to consist primarily of natural minerals. These colloids were found to contain detectable amounts of strongly sorbed radionuclides, leading to the hypothesis that radionuclides are being transported by the groundwater in colloidal form. The RNM ditch at the Cambric site has provided a unique tritium-labeled, irrigated test plot in the desert. One study at this site continued earlier investigations of water and tritium migration in the shallow vadose (unsaturated-soil) zone adjacent to the ditch and extended that study to include using a tracer to determine the velocity of vertical water flow in the recharge zone directly below the ditch. 57 refs., 15 figs., 23 tabs

  14. Climate change-related migration and infectious disease.

    Science.gov (United States)

    McMichael, Celia

    2015-01-01

    Anthropogenic climate change will have significant impacts on both human migration and population health, including infectious disease. It will amplify and alter migration pathways, and will contribute to the changing ecology and transmission dynamics of infectious disease. However there has been limited consideration of the intersections between migration and health in the context of a changing climate. This article argues that climate-change related migration - in conjunction with other drivers of migration - will contribute to changing profiles of infectious disease. It considers infectious disease risks for different climate-related migration pathways, including: forced displacement, slow-onset migration particularly to urban-poor areas, planned resettlement, and labor migration associated with climate change adaptation initiatives. Migration can reduce vulnerability to climate change, but it is critical to better understand and respond to health impacts - including infectious diseases - for migrant populations and host communities.

  15. [Role of connective tissue growth factor (CTGF) in proliferation and migration of pancreatic cancer cells].

    Science.gov (United States)

    Bai, Yu-chun; Kang, Quan; Luo, Qing; Wu, Dao-qi; Ye, Wei-xia; Lin, Xue-mei; Zhao, Yong

    2011-10-01

    To explore the expression of connective tissue growth factor (CTGF) in pancreatic cancer and its influence on the proliferation and migration of cancer cells. The expression of CTGF in pancreatic cell line PANC-1 cells was analyzed by real-time PCR and in pancreatic carcinoma (50 cases) tissues by immunohistochemistry. The ability of proliferation and migration in vitro of PANC-1 cells was tested by MTT assay, scratch test and Boyden chamber test after the CTGF gene was overexpressed by Ad5-CTGF or silenced with Ad5-siCTGF transfection. CTGF was overexpressed in both pancreatic cancer cells and tissues. Overxpression of CTGF leads to increased proliferation and migration of PANC-1 cells. The CTGF-transfected PANC-1 cells showed apparent stronger proliferation ability and scratch-repair ability than that of empty vector controls. The results of Boyden chamber test showed that there were 34 cells/field (200× magnificantion) of the CTGF-transfected overexpressing cells, much more than the 11 cells/field of the empty vector control cells; and 6 cells/microscopic field of the Ad5-siCTGF-transfected silenced cells, much less than the 15 cells/field of the control cells. CTGF is overexpressed in both pancreatic cancer cells in vitro and in vivo, indicating that it may play an important role in the cell proliferation and migration in pancreatic cancer.

  16. Migrating Art History

    DEFF Research Database (Denmark)

    Ørum, Tania

    2012-01-01

    Review of Hiroko Ikegami, The Great Migrator. Robert Rauschenberg and the Global Rise of American Art. Cambridge Mass., The MIT Press, 2010. 277 pages. ISBN 978-0-262-01425-0.......Review of Hiroko Ikegami, The Great Migrator. Robert Rauschenberg and the Global Rise of American Art. Cambridge Mass., The MIT Press, 2010. 277 pages. ISBN 978-0-262-01425-0....

  17. Pre-migration Trauma Exposure and Psychological Distress for Asian American Immigrants: Linking the Pre- and Post-migration Contexts.

    Science.gov (United States)

    Li, Miao; Anderson, James G

    2016-08-01

    Drawing on the life course perspective and the assumptive world theory, this paper examines whether pre-migration trauma exposure is associated with psychological distress through post-migration perceived discrimination for Asian American immigrants. The study is based on cross-sectional data from the National Latino and Asian American Study (N = 1639). Structural equation model is used to estimate the relationship between pre-migration trauma, post-migration perceived discrimination, and psychological distress. Additional models are estimated to explore possible variations across ethnic groups as well as across different types of pre-migration trauma experience. Pre-migration trauma exposure is associated with higher levels of psychological distress, both directly and indirectly through higher level of perceived discrimination, even after controlling for demographic/acculturative factors and post-migration trauma exposure. This pattern holds for the following sub-types of pre-migration trauma: political trauma, crime victimization, physical violence, accidental trauma, and relational trauma. Multi-group analyses show that this pattern holds for all Asian immigrant subgroups except the Vietnamese. Studies of immigrant mental health primarily focus on post-migration stressors. Few studies have considered the link between pre- and post-migration contexts in assessing mental health outcomes. The study illustrates the usefulness of bridging the pre- and post-migration context in identifying the mental health risks along the immigrant life course.

  18. Male out-migration: a factor for the spread of HIV infection among married men and women in rural India.

    Directory of Open Access Journals (Sweden)

    Niranjan Saggurti

    Full Text Available INTRODUCTION: Thus far, the reasons for increasing HIV prevalence in northern and eastern Indian states are unknown. We investigated the role of male out-migration in the spread of human immunodeficiency virus (HIV infection through a case-control study in rural India. METHODS: Currently married men and women were recruited from HIV testing and treatment centers across seven selected districts with high rates of male out-migration in eastern and northern India in 2010 using a case-control study design. Case subjects (men: 595, women: 609 were people who tested HIV seropositive and control subjects (men: 611, women: 600 were those tested HIV seronegative. For each gender, we obtained adjusted odds ratios (AORs and population attributable risks (PARs for migration, and behavioral factors. RESULTS: For men, the prevalence of HIV was significantly higher among those with a migration history (AOR, 4.4; for women, the prevalence of HIV was higher among those with migrant husbands (AOR, 2·3. For both genders, the returned male migration (men: AOR, 3·7; women: AOR, 28 was significantly associated with higher prevalence of HIV infection. The PAR associated with male migration was higher for men (54.5%-68.6% than for women (32·7%-56·9% across the study areas. DISCUSSION: Male out-migration is the most important risk factor influencing the spread of HIV infection in rural areas with high out-migration rates, thereby emphasizing the need for interventions, particularly, for returned migrants and spouses of those migrants.

  19. Globalisation and international migration in Asia.

    Science.gov (United States)

    Hugo, G

    1998-03-01

    "The present paper attempts to summarise the major contemporary trends in international migration in Asia and how this is related to the rapid demographic transition occurring across most of the region. The diversity of types of mobility is one of the striking features of Asian international migration and developments in each major type [are] discussed in the paper. It is then argued that there are elements within the Asian migration system that give it a momentum which to some extent operates outside of the influence of economic and political trends. Finally some emerging issues in Asian international migration are briefly addressed. These include the scale and effects of remittances, the feminisation of migration, undocumented migration, increasing government involvement and brain drain issues." (EXCERPT)

  20. Youth Labor Migration in Nepal

    OpenAIRE

    Bossavie, Laurent; Denisova, Anastasiya

    2018-01-01

    This descriptive study investigates internal and external labor migration by Nepalese youth. External labor migration is separated into the flow to India, which is unregulated, and the flow to other countries, which typically takes the form of temporary contract migration to countries with bilateral labor agreements with Nepal (referred to in Nepal as foreign employment). The study finds t...

  1. Green Light for Nocturnally Migrating Birds

    Directory of Open Access Journals (Sweden)

    Hanneke Poot

    2008-12-01

    Laboratory experiments have shown the magnetic compass to be wavelength dependent: migratory birds require light from the blue-green part of the spectrum for magnetic compass orientation, whereas red light (visible long-wavelength disrupts magnetic orientation. We designed a field study to test if and how changing light color influenced migrating birds under field conditions. We found that nocturnally migrating birds were disoriented and attracted by red and white light (containing visible long-wavelength radiation, whereas they were clearly less disoriented by blue and green light (containing less or no visible long-wavelength radiation. This was especially the case on overcast nights. Our results clearly open perspective for the development of bird-friendly artificial lighting by manipulating wavelength characteristics. Preliminary results with an experimentally developed bird-friendly light source on an offshore platform are promising. What needs to be investigated is the impact of bird-friendly light on other organisms than birds.

  2. Repeat migration and disappointment.

    Science.gov (United States)

    Grant, E K; Vanderkamp, J

    1986-01-01

    This article investigates the determinants of repeat migration among the 44 regions of Canada, using information from a large micro-database which spans the period 1968 to 1971. The explanation of repeat migration probabilities is a difficult task, and this attempt is only partly successful. May of the explanatory variables are not significant, and the overall explanatory power of the equations is not high. In the area of personal characteristics, the variables related to age, sex, and marital status are generally significant and with expected signs. The distance variable has a strongly positive effect on onward move probabilities. Variables related to prior migration experience have an important impact that differs between return and onward probabilities. In particular, the occurrence of prior moves has a striking effect on the probability of onward migration. The variable representing disappointment, or relative success of the initial move, plays a significant role in explaining repeat migration probabilities. The disappointment variable represents the ratio of actural versus expected wage income in the year after the initial move, and its effect on both repeat migration probabilities is always negative and almost always highly significant. The repeat probabilities diminish after a year's stay in the destination region, but disappointment in the most recent year still has a bearing on the delayed repeat probabilities. While the quantitative impact of the disappointment variable is not large, it is difficult to draw comparisons since similar estimates are not available elsewhere.

  3. Impact of tumor cell cytoskeleton organization on invasiveness and migration: a microchannel-based approach.

    Directory of Open Access Journals (Sweden)

    Claudio G Rolli

    2010-01-01

    Full Text Available Cell migration is a fundamental feature of the interaction of cells with their surrounding. The cell's stiffness and ability to deform itself are two major characteristics that rule migration behavior especially in three-dimensional tissue. We simulate this situation making use of a micro-fabricated migration chip to test the active invasive behavior of pancreatic cancer cells (Panc-1 into narrow channels. At a channel width of 7 microm cell migration through the channels was significantly impeded due to size exclusion. A striking increase in cell invasiveness was observed once the cells were treated with the bioactive lipid sphingosylphosphorylcholine (SPC that leads to a reorganization of the cell's keratin network, an enhancement of the cell's deformability, and also an increase in the cell's migration speed on flat surfaces. The migration speed of the highly deformed cells inside the channels was three times higher than of cells on flat substrates but was not affected upon SPC treatment. Cells inside the channels migrated predominantly by smooth sliding while maintaining constant cell length. In contrast, cells on adhesion mediating narrow lines moved in a stepwise way, characterized by fluctuations in cell length. Taken together, with our migration chip we demonstrate that the dimensionality of the environment strongly affects the migration phenotype and we suggest that the spatial cytoskeletal keratin organization correlates with the tumor cell's invasive potential.

  4. Socio-Economic Determinants of International Migration

    Directory of Open Access Journals (Sweden)

    Yaroslav PRYTULA

    2012-05-01

    Full Text Available Since economic factors cannot fully explain the determinants of bilateral migration, this study explores the social and cultural determinants that influence an individual’s decision to migrate. Values, norms and interests in a given culture, may determine whether an individual’s intention to move translates into actual migration. Work values inherent in different cultures could explain why people move or do not move under the condition of perceived economic advantages of migration. A gravity type migration model is used to incorporate variables related both to economic indicators and work values. It is perhaps the first migration study to use the World Value Survey (WVS and the European Value Survey (EVS. We use 2000 stock bilateral migration dataset collected by the World Bank. Our findings indicate that if more aspects of work are valued in a country, this country sends more migrants. Also we show that countries with higher extrinsic work value orientation tend to send more migrants, while countries with higher intrinsic work value orientation tend to send fewer migrants. Our finding shows that the value of work and the level of job security in a country may significantly change migration decision.

  5. Effect of several variables in the polymer toys additive migration to saliva.

    Science.gov (United States)

    Noguerol-Cal, R; López-Vilariño, J M; González-Rodríguez, M V; Barral-Losada, L

    2011-09-30

    Capacity to migrate of a representative group of polymeric additives, dyes, antioxidants, hindered amine light stabilizers (HALS) or antistatics, from plastic toys to saliva was analyzed to protect children in their habits of sucking and biting. Most of target additives appear no-regulated in toys normative but adverse effects on human health of some of them have been demonstrated and their presence in others commercial articles normative has been included. In order to offer an effective and easy tool to perform these controls, migration tests by dynamic and static contact, followed by a preconcentration step by liquid-liquid extraction (LLE) and ultra performance liquid chromatographic analysis with ultraviolet-visible and evaporative light scattering detections (UPLC-UV/Vis-ELSD) have been optimized to evaluate the migrated amounts of the additives in saliva simulant. The detection limits of the migration methodologies were ranged from 8.68 × 10(-2) to 1.30 × 10(-3)mg migrated (L simulant)(-1). Influence of several variables on this mass transport, as time, temperature and friction, was also analyzed to achieve the most aggressive methodology to protect consumers. Migration of several studied additives, whose presence has been demonstrated in several purchased commercial toys, has been observed. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Asymptomatic bacteriuria in pregnant women attending Boo-Ali Hospital Tehran Iran: Urine analysis vs. urine culture.

    Science.gov (United States)

    Etminan-Bakhsh, Mina; Tadi, Sima; Darabi, Roksana

    2017-11-01

    Asymptomatic bacteriuria is one of the common problems in pregnancy. Asymptomatic bacteriuria is associated with pyelonephritis, preterm labor and low birth weight infants. The physiological and anatomical changes in pregnancy facilitate urinary tract infection (UTI) during pregnancy. Several tests are available for diagnosis of asymptomatic bacteriuria. The urine culture is a gold standard diagnostic test for asymptomatic bacteriuria but it is expensive and time-consuming. Screening methods may be useful in detecting high-risk pregnant women for asymptomatic bacteriuria. The aim of the present study was to compare urine analysis as a rapid screening test to urine culture in diagnosis of asymptomatic bacteriuria. A total of 123 pregnant women attending the obstetrics clinic of Boo-Ali hospital in Tehran, Iran from March 2013 to September 2014 were included in the present diagnostic cross-sectional study. One hundred twenty three mid-stream urine samples were inoculated into cultures and were processed by dipstick (nitrite test and leucocyte esterase test) and microscopic pus cell count. The sensitivity, specificity, positive predictive value and negative predictive value of nitrite test, leucocyte esterase test and microscopic pus cell count were compared with urine culture in diagnosis of asymptomatic bacteriuria by using SPSS version 19. Of 123 urine samples, significant asymptomatic bacteriuria (≥10 4 cfu/Ml) was detected in 8 (6.5%) subjects. The sensitivity and specificity of nitrite test were 37% and 100% respectively. The sensitivity of pus cell count alone and leucocyte esterase test alone were 100% but the specificity of them were 64% and 65% respectively. We found high negative predictive value by Pus cell count and the leucocyte esterase test (100%) and low positive predictive value by them (16% and 17% respectively). Urine culture is the most useful test for diagnosis of asymptomatic bacteriuria. None of our screening tests had a sensitivity and

  7. Wages, Welfare Benefits and Migration.

    Science.gov (United States)

    Kennan, John; Walker, James R

    2010-05-01

    Differences in economic opportunities give rise to strong migration incentives, across regions within countries, and across countries. In this paper we focus on responses to differences in welfare benefits across States. We apply the model developed in Kennan and Walker (2008), which emphasizes that migration decisions are often reversed, and that many alternative locations must be considered. We model individual decisions to migrate as a job search problem. A worker starts the life-cycle in some home location and must determine the optimal sequence of moves before settling down. The model is sparsely parameterized. We estimate the model using data from the National Longitudinal Survey of Youth (1979). Our main finding is that income differences do help explain the migration decisions of young welfare-eligible women, but large differences in benefit levels provide surprisingly weak migration incentives.

  8. Measuring International Migration in Azerbaijan

    Directory of Open Access Journals (Sweden)

    Serhat Yüksel

    2018-01-01

    Full Text Available International migration significantly affects economic, social, cultural, and political factors of the country. Owing to this situation, it can be said that the reasons of international migration should be analyzed in order to control this problem. The purpose of this study is to determine the influencing factors of international migration in Azerbaijan. In this scope, annual data of 11 explanatory variables for the period of 1995–2015 was analyzed via Multivariate Adaptive Regression Splines (MARS method. According to the results of this analysis, it was identified that people prefer to move other countries in case of high unemployment rates. In addition, the results of the study show that population growth and high mortality rate increases the migration level. While considering these results, it was recommended that Azerbaijan should focus on these aspects to control international migration problem.

  9. Labor migration in Asia.

    Science.gov (United States)

    Martin, P L

    1991-01-01

    "A recent conference sponsored by the United Nations Center for Regional Development (UNCRD) in Nagoya, Japan examined the growing importance of labor migration for four major Asian labor importers (Japan, Hong Kong, Malaysia, and Singapore) and five major labor exporters (Bangladesh, Korea, Pakistan, Philippines, and Thailand).... The conference concluded that international labor migration would increase within Asia because the tight labor markets and rising wages which have stimulated Japanese investment in other Asian nations, for example, have not been sufficient to eliminate migration push and pull forces...." excerpt

  10. Optimum Pathways of Fish Spawning Migrations in Rivers

    Science.gov (United States)

    McElroy, B. J.; Jacobson, R. B.; Delonay, A.

    2010-12-01

    Many fish species migrate large distances upstream in rivers to spawn. These migrations require energetic expenditures that are inversely related to fecundity of spawners. Here we present the theory necessary to quantify relative energetic requirements of upstream migration pathways and then test the hypothesis that least-cost paths are taken by the federally endangered pallid sturgeon (Scaphyrhyncus Albus), a benthic rheophile, in the lower Missouri River, USA. Total work done by a fish through a migratory path is proportional to the size of the fish, the total drag on the fish, and the distance traversed. Normalizing by the work required to remain stationary at the beginning of a path, relative work expenditure at each point of the path is found to be the cube of the ratio of the velocity along the path to the velocity at the start of the path. This is the velocity of the fish relative to the river flow. A least-cost migratory pathway can be determined from the velocity field in a reach as the path that minimizes a fish's relative work expenditure. We combine location data from pallid sturgeon implanted with telemetric tags and pressure-sensitive data storage tags with depth and velocity data collected with an acoustic Doppler profiler. During spring 2010 individual sturgeon were closely followed as they migrated up the Missouri River to spawn. These show that, within a small margin, pallid sturgeon in the lower Missouri River select least-cost paths as they swim upstream (typical velocities near 1.0 - 1.2 m/s). Within the range of collected data, it is also seen that many alternative paths not selected for migration are two orders of magnitude more energetically expensive (typical velocities near 2.0 - 2.5 m/s). In general these sturgeon migrated along the inner banks of bends avoiding high velocities in the thalweg, crossing the channel where the thalweg crosses in the opposite direction in order to proceed up the inner bank of subsequent bends. Overall, these

  11. Optimum swimming pathways of fish spawning migrations in rivers

    Science.gov (United States)

    McElroy, Brandon; DeLonay, Aaron; Jacobson, Robert

    2012-01-01

    Fishes that swim upstream in rivers to spawn must navigate complex fluvial velocity fields to arrive at their ultimate locations. One hypothesis with substantial implications is that fish traverse pathways that minimize their energy expenditure during migration. Here we present the methodological and theoretical developments necessary to test this and similar hypotheses. First, a cost function is derived for upstream migration that relates work done by a fish to swimming drag. The energetic cost scales with the cube of a fish's relative velocity integrated along its path. By normalizing to the energy requirements of holding a position in the slowest waters at the path's origin, a cost function is derived that depends only on the physical environment and not on specifics of individual fish. Then, as an example, we demonstrate the analysis of a migration pathway of a telemetrically tracked pallid sturgeon (Scaphirhynchus albus) in the Missouri River (USA). The actual pathway cost is lower than 105 random paths through the surveyed reach and is consistent with the optimization hypothesis. The implication—subject to more extensive validation—is that reproductive success in managed rivers could be increased through manipulation of reservoir releases or channel morphology to increase abundance of lower-cost migration pathways.

  12. IUSSP Committee on International Migration, Workshop on International Migration Systems and Networks.

    Science.gov (United States)

    Lim, Lin Lean

    1987-01-01

    This mini-workshop sought a framework for examining the dynamics of migration processes, especially the interlinkages between sending and receiving countries. These two focuses emerged as directions for further research: (1) a topology reflecting the concepts underlying international migration; and (2) empirical studies which attempt to apply the…

  13. Determinants of the Egyptian labour migration.

    Science.gov (United States)

    Kandil, M; Metwally, M

    1992-03-01

    The objective is to summarize the pattern of Egyptian migration to Arab oil-producing countries (AOPC), to review some factors that are important determinants of labor movement based on theory, and to empirically model the migration rate to AOPC and to Saudi Arabia. Factors are differentiated as to their relative importance. Push factors are the low wages, high inflation rate, and high population density in Egypt; pull factors are higher wages. It is predicted that an increase in income from destination countries has a significant positive impact on the migration rate. An increase in population density stimulates migration. An increase in inflation acts to increase out-migration with a 2-year lag, which accommodates departure preparation. Egypt's experience with labor migration is described for the pre-oil boom, and the post-oil boom. Several estimates of labor migration are given. Government policy toward migration is positive. Theory postulates migration to be determined by differences in the availability of labor, labor rewards between destination and origin, and the cost of migration. In the empirical model, push factors are population density, the current inflation rate, and the ratio of income/capita in AOPC to Egypt. The results indicate that the ratio of income/capita had a strong pull impact and population density had a strong push impact. The inflation rate has a positive impact with a lag estimated at 2 years. Prior to the Camp David Accord, there was a significant decrease in the number of Egyptian migrants due to political tension. The findings support the classical theory of factor mobility. The consequences of migration on the Egyptian economy have been adverse. Future models should disaggregate data because chronic shortages exist in some parts of the labor market. Manpower needs assessment would be helpful for policy makers.

  14. Transnational Solidarity—Not Aid: The Perspective of Migration on the Hype about Migration&Development

    Directory of Open Access Journals (Sweden)

    Maria Schwertl

    2017-09-01

    Full Text Available Migrants have organized transnational support for non-migrants, stay-at-homes, citizens and noncitizens, as well as for developmental or integrationist nation state projects for decades. These solidarities have been framed as “cultural programs,” “autochthone support of hometowns,” “development aid” or “diaspora politics.” Since the turn of the century especially those projects that could be framed as “development aid” have gained a lot of interest from official development aid and its agencies. More and more programs have been launched to coordinate and professionalize the transnational support labor of migrants under the aegis of development. This is what I call the hype about migration&development. In this article, I want to show why the notion of “migrant development aid” used in the hype falls short of what is at stake when it comes to transnational migrant solidarities. Thereby, I want to argue that looking at migration through its governance and through migration or development politics is short-sighted and insensitive towards the desires, ethics and politics of migration. This is the reason that a perspective of migration—such as that propagated by the autonomy of migration approach—needs to be brought into debates on migration&development.

  15. Quantifying Migration Behaviour Using Net Squared Displacement Approach: Clarifications and Caveats.

    Directory of Open Access Journals (Sweden)

    Navinder J Singh

    Full Text Available Estimating migration parameters of individuals and populations is vital for their conservation and management. Studies on animal movements and migration often depend upon location data from tracked animals and it is important that such data are appropriately analyzed for reliable estimates of migration and effective management of moving animals. The Net Squared Displacement (NSD approach for modelling animal movement is being increasingly used as it can objectively quantify migration characteristics and separate different types of movements from migration. However, the ability of NSD to properly classify the movement patterns of individuals has been criticized and issues related to study design arise with respect to starting locations of the data/animals, data sampling regime and extent of movement of species. We address the issues raised over NSD using tracking data from 319 moose (Alces alces in Sweden. Moose is an ideal species to test this approach, as it can be sedentary, nomadic, dispersing or migratory and individuals vary in their extent, timing and duration of migration. We propose a two-step process of using the NSD approach by first classifying movement modes using mean squared displacement (MSD instead of NSD and then estimating the extent, duration and timing of migration using NSD. We show that the NSD approach is robust to the choice of starting dates except when the start date occurs during the migratory phase. We also show that the starting location of the animal has a marginal influence on the correct quantification of migration characteristics. The number of locations per day (1-48 did not significantly affect the performance of non-linear mixed effects models, which correctly distinguished migration from other movement types, however, high-resolution data had a significant negative influence on estimates for the timing of migrations. The extent of movement, however, had an effect on the classification of movements, and

  16. Migration assay on primary culture isolated from patient's primary breast cancer tissue

    Directory of Open Access Journals (Sweden)

    ED Yuliana

    2014-12-01

    Full Text Available Background: Migration is an essential component of breast cancer metastasis, which studyhas been concentrated on culture of established breast cancer cell lines that do not accuratelyrepresent the sophistication and heterogeneity of patient's breast cancer. An attempt toperform migration assay using Boyden Chamber Assay (BCA on primary culture originatingfrom patient's breast cancer tissue was developed to accommodate upcoming study of breastcancer migration in lndonesian patients.Methods: Pathologically proven primary breast cancer tissue samples were obtained fromCiptomangunkusumo Hospital during core (n=4 and incisional (n=3 biopsies of stage llAup to stage lllA breast cancer patients. Following biopsy, the breast cancer tissue samplesunderwent processings to isolate the cancer cells. These cancer cells were -then resuspendedwithin Dulbecco's modified Eagle's medium (DMEM ahd cultured in 12-well plate. The growthof primary culture were observed and compared between the core biopsy and the incisionalbiopsy specimens. Optimization of BCA method was later performed to investigate themigration of the breast cancer primary culture towards different experirnental conditions, whichwere control, Fetal Bovine Serum (FBS, and Stromal Derived Factor-l (SDF-1. Two differentnumber of breast cancer cells were tested for the optimization of the BCA, which were 1 x 105and3x105cells.Results: None of the culture performed on core biopsy specimens grew, while one out ofthree incisional biopsy specimens grew until confluence. The one primary culture that grewwas later assesed using BCA to assess its migration index towards different experimentalconditions. Using 1 x 10s breast cancer cells in the BCA , the result of the absorbance level ofmigrated cells showed that the migration towards SDF-1 (0.529 nearly doubled the migrationtowards controlmedium (0.239 and FBS (0.209. Meanwhile, the absorbance levelwas simiiarbetween the control medium (1.050, FBS (1 .103

  17. Dynamic Migration Intentions and the Impact of Socio-Institutional Environments: A Transit Migration Hub in Turkey

    NARCIS (Netherlands)

    Wissink, M.J.; Düvell, F.; van Eerdewijk, A.

    2013-01-01

    Transit migration is generally defined by migrants having the intention to move onwards to a third country. Based on an empirical investigation in Izmir, a transit migration hub in Turkey, this paper critically discusses intentionality as a valid dimension in conceptualisations of transit migration.

  18. Suture fixation of migrated septal occluder device to prevent further migration: a simple surgical technique

    Directory of Open Access Journals (Sweden)

    Mohite Prashant N

    2013-01-01

    Full Text Available Abstract As the use of percutaneous intervention is increasing for the closure of the atrial septal defect, the procedure related complications are also on rise, migration of the device being most common. The migrated devices with failed percutaneous retrieval must be removed surgically under cardiopulmonary bypass. During establishment of cardiopulmonary bypass, the handling of heart may cause further migration of the device into other chambers of heart which leads to difficulty in finding and retrieval of the device. The authors propose a simple and unique technique to prevent further migration of the septal occluder device.

  19. Subarachnoid administration of iohexol in cynomolgus monkeys

    International Nuclear Information System (INIS)

    Drobeck, H.P.; Mayes, B.A.; Barbolt, T.A.; Fabian, R.J.; Kimball, J.P.; Slighter, R.R. Jr.

    1986-01-01

    A non-ionic diagnostic medium, iohexol, was administered by subarachnoid injection to groups of six cynomolgus monkeys and compared with the vehicle, physiologically normal saline, and/or saline of equal osmolality to determine its potential for increasing total protein and leucocyte levels in cerebrospinal fluid. Also investigated was the effect of repeated spinal taps not subsequently followed by the intrathecal injection of test or control articles. In the monkey, unlike man, low-level leucocyte counts were consistently observed following initial withdrawal of spinal fluid. Elevated leucocyte and total protein levels were observed in the present investigations one day to a week after intrathecal injection of radiopaque, vehicle or saline solution. Total protein returned to normal levels earlier than did leucocyte counts. However, repeated needle puncture alone was found to be sufficient to cause an elevation of leucocytes 3 to 4 times the baseline level, while inflammatory effects were observed histologically only when autopsy was performed soon after the final spinal tap. (orig.)

  20. Laboratory and field studies related to the Hydrology/Radionuclide Migration Project

    International Nuclear Information System (INIS)

    Thompson, J.L.

    1991-05-01

    This annual report describes research conducted in FY 1990 by Los Alamos National Laboratory for the Hydrology/Radionuclide Migration Project. This multi-agency project measures the underground movement of radionuclides related to nuclear testing at the Nevada Test Site. This project continues the long-term experiment at the site of the Cambric nuclear test. Water pumped from a well adjacent to the explosion cavity continues to show decreasing amounts of tritium and Krypton 85 but no Cesium 139. Analyses of drillback debris shows a distinction between refractory and volatile materials in respect to both their location in the test cavity and their leachability with groundwater. We surveyed materials used during nuclear testing to evaluate any post-test hazard; we concluded that most such materials pose a minimal hazard. The Los Alamos drilling program provided an opportunity for us to sample a collapsed zone above the cavity of a test, which was fired 2 years ago. We continue our research in colloid characterization and in detection of low levels of Technetium 99 in Nevada Test Site water. During FY 1990, we drilled a new hole in the Yucca Flat area to study radionuclide migration. This report also describes Los Alamos management and planning activities in support of this project. 20 refs., 2 figs., 14 tabs

  1. Mental health of newly arrived Burmese refugees in Australia: contributions of pre-migration and post-migration experience.

    Science.gov (United States)

    Schweitzer, Robert D; Brough, Mark; Vromans, Lyn; Asic-Kobe, Mary

    2011-04-01

    This study documents the mental health status of people from Burmese refugee backgrounds recently arrived in Australia, then examines the contributions of gender, pre-migration and post-migration factors in predicting mental health. Structured interviews, including a demographic questionnaire, the Harvard Trauma Questionnaire, the Post-migration Living Difficulties Checklist and Hopkins Symptom Checklist assessed pre-migration trauma, post-migration living difficulties, depression, anxiety, somatization and traumatization symptoms in a sample of 70 adults across five Burmese ethnic groups. Substantial proportions of participants reported psychological distress in symptomatic ranges including: post-traumatic stress disorder (9%), anxiety (20%) and depression (36%), as well as significant symptoms of somatization (37%). Participants reported multiple and severe pre-migration traumas. Post-migration living difficulties of greatest concern included communication problems and worry about family not in Australia. Gender did not predict mental health. Level of exposure to traumatic events and post-migration living difficulties each made unique and relatively equal contributions to traumatization symptoms. Post-migration living difficulties made unique contributions to depression, anxiety and somatization symptoms. While exposure to traumatic events impacted on participants' mental well-being, post-migration living difficulties had greater salience in predicting mental health outcomes of people from Burmese refugee backgrounds. Reported rates of post-traumatic stress disorder symptoms were consistent with a large review of adults across seven western countries. High levels of somatization point to a nuanced expression of distress. Findings have implications for service provision in terms of implementing appropriate interventions to effectively meet the needs of this newly arrived group in Australia.

  2. The health impacts of climate-related migration.

    Science.gov (United States)

    Schwerdtle, Patricia; Bowen, Kathryn; McMichael, Celia

    2017-12-11

    Changes in climate, in conjunction with other drivers of mobility, shape human migration. While there is an increasing focus on the adaptive potential of migration, the health impacts of climate-related migration, including planned relocation and forced displacement, have not been thoroughly examined. The Intergovernmental Panel on Climate Change stated that migration is currently, and will increasingly be, influenced by environmental degradation and climate change, and that it needs to be addressed in a focused and coordinated manner. This paper examines the links between climate change, migration, and health, considering diverse migration responses, including immobility, forced displacement and planned migration, as well as the associated health risks and opportunities in different contexts. Using case studies, the paper illustrates strategies to reduce the health risks associated with climate change-related migration. While there is an increasing body of research examining the climate change-migration nexus, a dual approach is now required. This approach must include debate and further research regarding the health consequences and responses associated with climate migration as well as immediate strengthening of health systems to make them both climate resilient and migrant inclusive.

  3. Migration in Burkina Faso

    NARCIS (Netherlands)

    Wouterse, F.S.

    2007-01-01

    Migration plays an important role in development and as a strategy for poverty reduction. A recent World Bank investigation finds a significant positive relationship between international migration and poverty reduction at the country level (Adams and Page 2003). Burkina Faso, whose conditions for

  4. Transmission Model of Hepatitis B Virus with the Migration Effect

    Directory of Open Access Journals (Sweden)

    Muhammad Altaf Khan

    2013-01-01

    Full Text Available Hepatitis B is a globally infectious disease. Mathematical modeling of HBV transmission is an interesting research area. In this paper, we present characteristics of HBV virus transmission in the form of a mathematical model. We analyzed the effect of immigrants in the model to study the effect of immigrants for the host population. We added the following flow parameters: “the transmission between migrated and exposed class” and “the transmission between migrated and acute class.” With these new features, we obtained a compartment model of six differential equations. First, we find the basic threshold quantity Ro and then find the local asymptotic stability of disease-free equilibrium and endemic equilibrium. Furthermore, we find the global stability of the disease-free and endemic equilibria. Previous similar publications have not added the kind of information about the numerical results of the model. In our case, from numerical simulation, a detailed discussion of the parameters and their numerical results is presented. We claim that with these assumptions and by adding the migrated class, the model informs policy for governments, to be aware of the immigrants and subject them to tests about the disease status. Immigrants for short visits and students should be subjected to tests to reduce the number of immigrants with disease.

  5. The Utility of the Extended Images in Ambient Seismic Wavefield Migration

    Science.gov (United States)

    Girard, A. J.; Shragge, J. C.

    2015-12-01

    Active-source 3D seismic migration and migration velocity analysis (MVA) are robust and highly used methods for imaging Earth structure. One class of migration methods uses extended images constructed by incorporating spatial and/or temporal wavefield correlation lags to the imaging conditions. These extended images allow users to directly assess whether images focus better with different parameters, which leads to MVA techniques that are based on the tenets of adjoint-state theory. Under certain conditions (e.g., geographical, cultural or financial), however, active-source methods can prove impractical. Utilizing ambient seismic energy that naturally propagates through the Earth is an alternate method currently used in the scientific community. Thus, an open question is whether extended images are similarly useful for ambient seismic migration processing and verifying subsurface velocity models, and whether one can similarly apply adjoint-state methods to perform ambient migration velocity analysis (AMVA). Herein, we conduct a number of numerical experiments that construct extended images from ambient seismic recordings. We demonstrate that, similar to active-source methods, there is a sensitivity to velocity in ambient seismic recordings in the migrated extended image domain. In synthetic ambient imaging tests with varying degrees of error introduced to the velocity model, the extended images are sensitive to velocity model errors. To determine the extent of this sensitivity, we utilize acoustic wave-equation propagation and cross-correlation-based migration methods to image weak body-wave signals present in the recordings. Importantly, we have also observed scenarios where non-zero correlation lags show signal while zero-lags show none. This may be a valuable missing piece for ambient migration techniques that have yielded largely inconclusive results, and might be an important piece of information for performing AMVA from ambient seismic recordings.

  6. Investigation on nuclide migration behaviors

    International Nuclear Information System (INIS)

    Baik, Minhoon; Park, Chungkyun; Kim, Seungsoo

    2012-04-01

    In this study, we investigated the properties of geochemical reactions and sorption of high-level radionuclides and highly-mobile radionuclides in deep geological disposal environments. We also analyzed the dissolution properties of pyro wastes and constructed databases for the geochemical reactions and sorption for the safety assessment of HLW disposal. Technologies for measuring diffusion depths of radionuclides through fracture surfaces and rock matrix were developed in KURT conditions and their diffusion properties were analyzed and evaluated. The combined reactions of radionuclide/mineral/microbe in deep disposal environments were investigated and the effects of microbe on the radionuclide migration and disposal system behaviors were evaluated. In-situ solute migration system and on-line monitoring system were installed in KURT and the migration and retardation behaviors of various solutes and their interaction with fracture-filling materials were investigated. Basic properties of KURT groundwater colloids were analyzed using various methods. In addition, in-situ colloid migration experiments through a rock fracture were carried out and the developed migration model was verified. We have participated in Colloid Formation and Migration (CFM) international joint project in GTS and obtained reliability for our research results by comparing research results each other

  7. A Cost-Effective Approach for Migrating Enterprise Electronic Mail Systems

    Directory of Open Access Journals (Sweden)

    Emmanuel Omojokun

    2008-02-01

    Full Text Available Electronic mail (E-mail is one of the most utilized application software systems in modern-day organizations. The major messaging application programs used in the enterprise are IBM Lotus Notes also known as Domino, Microsoft Exchange Servers, and Novel GroupWise. For various reasons – such as high cost of maintenance, undeliverable e-mail issue and loss of attachments, companies find it necessary to either migrate to newer versions of their messaging software or to an entirely different software. In either case, the process must be carefully planned, well designed and properly implemented to avoid disaster. In this paper, we present a cost-effective approach for migrating a particular messaging software. The approach was implemented and tested for the migration of GroupWise 5.5 to Exchange Server 2003. We present our success story and lessons learned from the case. A six-week and one-year post migration system-audits indicated that the organization derived several benefits including significant cost savings as a result of this particular approach. Chief information/technology officers and e-mail administrators will benefit immensely from the "best practice" strategy hereby presented.

  8. Temporal genetic population structure and interannual variation in migration behavior of Pacific Lamprey Entosphenus tridentatus

    Science.gov (United States)

    Clemens, Benjamin J.; Wyss, Lance A.; McCoun, Rebecca; Courter, Ian; Schwabe, Lawrence; Peery, Christopher; Schreck, Carl B.; Spice, Erin K.; Docker, Margaret F.

    2017-01-01

    Studies using neutral loci suggest that Pacific lamprey, Entosphenus tridentatus, lack strong spatial genetic population structure. However, it is unknown whether temporal genetic population structure exists. We tested whether adult Pacific lamprey: (1) show temporal genetic population structure; and (2) migrate different distances between years. We non-lethally sampled lamprey for DNA in 2009 and 2010 and used eight microsatellite loci to test for genetic population structure. We used telemetry to record the migration behaviors of these fish. Lamprey were assignable to three moderately differentiated genetic clusters (FST = 0.16–0.24 for all pairwise comparisons): one cluster was composed of individuals from 2009, and the other two contained individuals from 2010. The FST value between years was 0.13 and between genetic clusters within 2010 was 0.20. A total of 372 (72.5%) fish were detected multiple times during their migrations. Most fish (69.9%) remained in the mainstem Willamette River; the remaining 30.1% migrated into tributaries. Eighty-two lamprey exhibited multiple back-and-forth movements among tributaries and the mainstem, which may indicate searching behaviors. All migration distances were significantly greater in 2010, when the amplitude of river discharge was greater. Our data suggest genetic structuring between and within years that may reflect different cohorts.

  9. Energetics of DNA repair: effects of temperature on DNA repair in UV-irradiated peripheral blood leucocytes from chronic myeloid leukemic patients

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, A.; Sharma, R.; Jain, V.K.

    1988-05-01

    The effects of different temperatures (34-43/sup 0/C) were studied on the repair of UV-induced (254-nm) DNA damage and its energetics in peripheral blood leucocytes of chronic myeloid leukaemic patients. DNA repair was measured by the unscheduled DNA synthesis (UDS) technique. Cellular energy supply was modulated by inhibitors of oxidative phosphorylation (antimycin-A) and glycolysis (2-deoxy-D-glucose). It was observed that there is an increase in the amount of DNA repair with increasing temperatures up to 40/sup 0/C and a fall thereafter. Longer periods of heat treatment (4 h) beyond 40/sup 0/C were observed to further decrease the DNA repair. Increasing temperatures were observed to have no significant effect on the parameters of energy metabolism. Further, the activation energy of DNA repair was calculated as 92 +- 46 kJ/mol (22 +- 11 kcal/mol), which did not alter significantly even in the presence of inhibitors of energy metabolism.

  10. Multiscale Cues Drive Collective Cell Migration

    Science.gov (United States)

    Nam, Ki-Hwan; Kim, Peter; Wood, David K.; Kwon, Sunghoon; Provenzano, Paolo P.; Kim, Deok-Ho

    2016-07-01

    To investigate complex biophysical relationships driving directed cell migration, we developed a biomimetic platform that allows perturbation of microscale geometric constraints with concomitant nanoscale contact guidance architectures. This permits us to elucidate the influence, and parse out the relative contribution, of multiscale features, and define how these physical inputs are jointly processed with oncogenic signaling. We demonstrate that collective cell migration is profoundly enhanced by the addition of contract guidance cues when not otherwise constrained. However, while nanoscale cues promoted migration in all cases, microscale directed migration cues are dominant as the geometric constraint narrows, a behavior that is well explained by stochastic diffusion anisotropy modeling. Further, oncogene activation (i.e. mutant PIK3CA) resulted in profoundly increased migration where extracellular multiscale directed migration cues and intrinsic signaling synergistically conspire to greatly outperform normal cells or any extracellular guidance cues in isolation.

  11. Selective Modulation of Integrin-mediated Cell Migration by Distinct ADAM Family MembersV⃞

    Science.gov (United States)

    Huang, Jing; Bridges, Lance C.; White, Judith M.

    2005-01-01

    A disintegrin and a metalloprotease (ADAM) family members have been implicated in many biological processes. Although it is recognized that recombinant ADAM disintegrin domains can interact with integrins, little is known about ADAM-integrin interactions in cellular context. Here, we tested whether ADAMs can selectively regulate integrin-mediated cell migration. ADAMs were expressed in Chinese hamster ovary cells that express defined integrins (α4β1, α5β1, or both), and cell migration on full-length fibronectin or on its α4β1 or α5β1 binding fragments was studied. We found that ADAMs inhibit integrin-mediated cell migration in patterns dictated by the integrin binding profiles of their isolated disintegrin domains. ADAM12 inhibited cell migration mediated by the α4β1 but not the α5β1 integrin. ADAM17 had the reciprocal effect; it inhibited α5β1- but not α4β1-mediated cell migration. ADAM19 and ADAM33 inhibited migration mediated by both α4β1 and α5β1 integrins. A point mutation in the ADAM12 disintegrin loop partially reduced the inhibitory effect of ADAM12 on cell migration on the α4β1 binding fragment of fibronectin, whereas mutations that block metalloprotease activity had no effect. Our results indicate that distinct ADAMs can modulate cell migration mediated by specific integrins in a pattern dictated, at least in part, by their disintegrin domains. PMID:16079176

  12. Water and contaminant movement: migration barriers

    International Nuclear Information System (INIS)

    Lane, L.J.; Nyhan, J.W.

    1984-11-01

    Migration barriers are used in shallow land burial facilities to slow or stop the movement of water and contaminants and are discussed here as a single component embedded in a complex environmental system. Analytical solutions to solute transport equations are used to approximate the behavior of migration barriers and to derive design criteria for control of subsurface water and contaminant migration. Various types of migration barriers are compared and design recommendations are made for shallow land burial trench caps and liners. Needed improvements and suggested field experiments for future designs of migration barriers are then discussed relative to the management of low-level radioactive wastes

  13. Migration, klima og sundhed

    DEFF Research Database (Denmark)

    Tellier, Siri; Carballo, Manuel

    2009-01-01

    Many tentative connections have been postulated between migration and climate. This article points to rural-urban migration, particularly into low elevation urban slums prone to flooding as an issue needing urgent attention by health professionals. It also notes the no-man's land in which environ...

  14. Climate Variability and Human Migration in the Netherlands, 1865–1937

    Science.gov (United States)

    Jennings, Julia A.; Gray, Clark L.

    2014-01-01

    Human migration is frequently cited as a potential social outcome of climate change and variability, and these effects are often assumed to be stronger in the past when economies were less developed and markets more localized. Yet, few studies have used historical data to test the relationship between climate and migration directly. In addition, the results of recent studies that link demographic and climate data are not consistent with conventional narratives of displacement responses. Using longitudinal individual-level demographic data from the Historical Sample of the Netherlands (HSN) and climate data that cover the same period, we examine the effects of climate variability on migration using event history models. Only internal moves in the later period and for certain social groups are associated with negative climate conditions, and the strength and direction of the observed effects change over time. International moves decrease with extreme rainfall, suggesting that the complex relationships between climate and migration that have been observed for contemporary populations extend into the nineteenth century. PMID:25937689

  15. Heterogeneous migration flows from the Central Plateau of Burkina Faso: the role of natural and social capital

    NARCIS (Netherlands)

    Wouterse, F.S.; Berg, van den M.M.

    2011-01-01

    This paper uses a system of labour supply equations and data from Burkina Faso collected in 2003 to test the conditions underlying two different migratory movements: continental and intercontinental migration. We provide theoretical reasoning and empirical evidence that heterogeneity in migration is

  16. Vulnerable to HIV / AIDS. Migration.

    Science.gov (United States)

    Fernandez, I

    1998-01-01

    This special report discusses the impact of globalization, patterns of migration in Southeast Asia, gender issues in migration, the links between migration and HIV/AIDS, and spatial mobility and social networks. Migrants are particularly marginalized in countries that blame migrants for transmission of infectious and communicable diseases and other social ills. Effective control of HIV/AIDS among migrant and native populations requires a multisectoral approach. Programs should critically review the privatization of health care services and challenge economic models that polarize the rich and the poor, men and women, North and South, and migrant and native. Programs should recognize the equality between locals and migrants in receipt of health services. Countermeasures should have input from migrants in order to reduce the conditions that increase vulnerability to HIV/AIDS. Gender-oriented research is needed to understand women's role in migration. Rapid assessment has obscured the human dimension of migrants' vulnerability to HIV. Condom promotion is not enough. Migration is a major consequence of globalization, which holds the promise, real or imagined, of prosperity for all. Mass migration can be fueled by explosive regional developments. In Southeast Asia, migration has been part of the process of economic development. The potential to emigrate increases with greater per capita income. "Tiger" economies have been labor importers. Safe sex is not practiced in many Asian countries because risk is not taken seriously. Migrants tend to be used as economic tools, without consideration of social adjustment and sex behavior among singles.

  17. Migration Flows: Measurement, Analysis and Modeling

    NARCIS (Netherlands)

    Willekens, F.J.; White, Michael J.

    2016-01-01

    This chapter is an introduction to the study of migration flows. It starts with a review of major definition and measurement issues. Comparative studies of migration are particularly difficult because different countries define migration differently and measurement methods are not harmonized.

  18. Gender-specific out-migration, deforestation and urbanization in the Ecuadorian Amazon

    Science.gov (United States)

    Barbieri, Alisson F.; Carr, David L.

    2005-07-01

    The Ecuadorian Amazon, one of the richest reserves of biodiversity in the world, has faced one of the highest rates of deforestation of any Amazonian nation. Most of this forest elimination has been caused by agricultural colonization that followed the discovery of oil fields in 1967. Since the 1990s, an increasing process of urbanization has also engendered new patterns of population mobility within the Amazon, along with traditional ways by which rural settlers make their living. However, while very significant in its effects on deforestation, urbanization and regional development, population mobility within the Amazon has hardly been studied at all, as well as the distinct migration patterns between men and women. This paper uses a longitudinal dataset of 250 farm households in the Northern Ecuadorian Amazon to understand differentials between men and women migrants to urban and rural destinations and between men and women non-migrants. First, we use hazard analysis based on the Kaplan-Meier (KM) estimator to obtain the cumulative probability that an individual living in the study area in 1990 or at time t, will out-migrated at some time, t+ n, before 1999. Results indicate that out-migration to other rural areas in the Amazon, especially pristine areas is considerably greater than out-migration to the growing, but still incipient, Amazonian urban areas. Furthermore, men are more likely to out-migrate to rural areas than women, while the reverse occurs for urban areas. Difference-of-means tests were employed to examine potential factors accounting for differentials between male and female out-migration to urban and rural areas. Among the key results, relative to men younger women are more likely to out-migrate to urban areas; more difficult access from farms to towns and roads constrains women's migration; and access to new lands in the Amazon-an important cause of further deforestation-is more associated with male out-migration. Economic factors such as

  19. Migration of plutonium and americium in the lithosphere

    International Nuclear Information System (INIS)

    Fried, S.; Friedman, A.M.; Hines, J.J.; Atcher, R.W.; Quarterman, L.A.; Volesky, A.

    1976-01-01

    When radionuclides are stored as wastes either in permanent repositories or in waste storage areas, the possibility of escape into the environment must be considered. Surface contamination and the transport and migration of radionuclides into the lithosphere through the agency of water are discussed. Water in the form of rain will inevitably wash contaminants into soils and thence into conducting rocks. The migration of radionuclides must follow widely varying paths. In porous rocks, water percolates easily under a slight pressure gradient and rapid movement of large volumes of water can result with concommitant transport of large amounts of contaminating materials. In relatively non-porous rocks such as Niagara limestones the transport meets much more resistance and the volumes of water conducted are correspondingly reduced. In such situations much of the migration of water and its solutes may be through cracks and fissures in the rock. Certain strata of rock or rock products may be almost impervious to flow of water and by this token may be considered to be an especially suitable container for long term safe storage of nuclear wastes, particularly if these strata are quiescent. A series of investigations was undertaken to examine the properties of rocks in acting as a retarding agent in the migration of radionuclides. The rocks that are discussed are Niagara limestone (chosen for its density and fine porosity), basalt from the National Reactor Test site, and Los Alamos tuff

  20. Cell migration is another player of the minute virus of mice infection

    Energy Technology Data Exchange (ETDEWEB)

    Garcin, Pierre O.; Panté, Nelly, E-mail: pante@zoology.ubc.ca

    2014-11-15

    The parvovirus minute virus of mice, prototype strain (MVMp), preferentially infects and kills cancer cells. This intrinsic MVMp oncotropism may depend in part on the early stages of MVMp infection. To test this hypothesis, we investigated the early events of MVMp infection in mouse LA9 fibroblasts and a highly invasive mouse mammary tumor cell line derived from polyomavirus middle T antigen-mediated transformation. Using a combination of fluorescence and electron microscopy, we found that various parameters of the cell migration process affect MVMp infection. We show that, after binding to the plasma membrane, MVMp particles rapidly cluster at the leading edge of migrating cells, which exhibit higher levels of MVMp uptake than non-motile cells. Moreover, promoting cell migration on a fibronectin matrix increased MVMp infection, and induction of epithelial–mesenchymal transition allowed MVMp replication in non-permissive epithelial cells. Hence, we propose that cell migration influences the early stages of MVMp infection. - Highlights: • We document early steps of MVMp infection. • We report that a fibronectin matrix promotes MVMp infection. • We show that cellular migration plays a role in MVMp uptake. • We show that epithelial–mesenchymal transition allows MVMp replication.