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Sample records for modified gianturco expandable

  1. Palliation of patients with esophagogastric neoplasms by insertion of a covered expandable modified Gianturco-Z endoprosthesis: experiences in 153 patients

    NARCIS (Netherlands)

    Bartelsman, J. F.; Bruno, M. J.; Jensema, A. J.; Haringsma, J.; Reeders, J. W.; Tytgat, G. N.

    2000-01-01

    We aimed to evaluate the short- and long-term outcomes of treatment by insertion of a covered expandable modified Gianturco-Z endoprosthesis (Song stent) in patients with esophagogastric malignancies. Consecutive patients with esophagogastric malignancies in whom a Song stent was inserted were

  2. Experimental study with modified Gianturco expandable stunt in the dog urethra

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Ryong; Han, Young Min; Leu, Chun Soo; Chung, Gyung Ho; Kim, Chong Soo; Choi, Ki Chul [Chonbuk National University College of Medicine, Chunju (Korea, Republic of); Song, Ho Young [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    1993-07-15

    Benign prostatic hyperplasia and urethral stricture are common causes of urethral obstruction over 50 years of age. To evaluate the usefulness of the Gianturo expandable stent for dilatation of the urethra, 14 single stents were placed in the posterior urethra (2 in prostatic urethra, 12 in membranous urethra), 20 in the anterior urethra. And 4 six - eight connected stents were positioned in the posterior urethra to straddle at the internal sphincter or external sphincter and followed up for 2 weeks (one dog), 1 month (two dog), 2 months (one dog), 3 months (one dog), 5 months (one dog), 9 months (three dog), and 14 months (two dogs). Seven of 18 stents in the posterior urethra and 5 of 20 in the anterior urethra wee migrated during the follow-up. By 2 weeks after placements, 100% expansion was achieved in the posterior urethra, but by 1 month in the anterior urethra. Partial or complete epithelial covering of the stents was observed 1 month after stent placement in the anterior urethra, but mucosal folds were observed in the anterior and posterior urethra. Urinary incontinence was not observed in all cases. Our experience suggest that Gianturco expandable stent can be used in dilating and maintaining the lumen of the prostatic urethra and urethral stricture.

  3. Experimental study with modified Gianturco expandable stunt in the dog urethra

    International Nuclear Information System (INIS)

    Lee, Sang Ryong; Han, Young Min; Leu, Chun Soo; Chung, Gyung Ho; Kim, Chong Soo; Choi, Ki Chul; Song, Ho Young

    1993-01-01

    Benign prostatic hyperplasia and urethral stricture are common causes of urethral obstruction over 50 years of age. To evaluate the usefulness of the Gianturo expandable stent for dilatation of the urethra, 14 single stents were placed in the posterior urethra (2 in prostatic urethra, 12 in membranous urethra), 20 in the anterior urethra. And 4 six - eight connected stents were positioned in the posterior urethra to straddle at the internal sphincter or external sphincter and followed up for 2 weeks (one dog), 1 month (two dog), 2 months (one dog), 3 months (one dog), 5 months (one dog), 9 months (three dog), and 14 months (two dogs). Seven of 18 stents in the posterior urethra and 5 of 20 in the anterior urethra wee migrated during the follow-up. By 2 weeks after placements, 100% expansion was achieved in the posterior urethra, but by 1 month in the anterior urethra. Partial or complete epithelial covering of the stents was observed 1 month after stent placement in the anterior urethra, but mucosal folds were observed in the anterior and posterior urethra. Urinary incontinence was not observed in all cases. Our experience suggest that Gianturco expandable stent can be used in dilating and maintaining the lumen of the prostatic urethra and urethral stricture

  4. Gianturco expandable wire stents for treatment of superior vena cava syndrome secondary to lung carcinoma

    International Nuclear Information System (INIS)

    Rosch, J.; Bedell, J.; Putnam, J.; Antonovic, R.; Uchida, B.

    1986-01-01

    Two patients with superior vena cava syndrome (SVCS) secondary to lung carcinoma which recurred after maximum-dose radiation therapy were treated with placement of modified Gianturco expandable wire stents constructed in the authors' research laboratory. Symptoms of SVCS disappeared in 24 hours after stent placement, and the patients remained asymptomatic to their last follow-up, 2 1/2 months after the procedure (to the submission of this abstract). Both stents were widely patent at that time on superior vena cavograms and draining well the head, neck, and upper extremity circulation to the right atrium

  5. Treatment of tracheobronchial stenosis with a self-expandable metallic stents

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    Kim, Yong Soo; Jeon, Seok Chol; Choi, Chul Seung; Choi, Yo Won; Hahm, Chang Kok [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    1994-07-15

    We analysed the role of modified Gianturco self-expandable stents in the treatment of tracheobronchial stenosis in 13 patients. We inserted modified Gianturco self-expandable stents under the fluoroscopic and bronchoscopic guidance. There were stenosis in the trachea(n=2), the right main bronchus(n=2), and the left main bronchus(n=9). The causes of the stenosis were endobronchial tuberculosis(n=10), intubation granuloma(n=1), restenosis after surgical reconstruction(n=2). Dyspnea or wheezing was improved within 1 or 2 days following the procedure. There were 32% and 22% respective increase in average FEV1 and FVC. Lung perfusion scan showed 9.6% increase of perfusion in the involved lung. No complications related to the procedure were encountered. During follow-up period of up to 31 months, 2 patients showed tracheal or bronchial restenosis, at 3 and 6 months, retrospectively. There was a distal migration of the stents in one case. During the follow up period after stent insertion, improvement of the obstructive changes and dyspnea persisted in 10 out of 13 patients. The modified Gianturco self-expandable metallic stents may be a good choice for the treatment of tracheobronchial stenosis, either as a primary treatment, or when the reconstruction failed.

  6. Modified gianturco biliary stent in benign and malignant obstruction: Results of long-term follow up

    International Nuclear Information System (INIS)

    Chung, Jin Young; Song, Ho Young; Han, Hyun Young; Han, Young Min; Chung, Gyung Ho; Kim, Chong Soo; Choi, Ki Chul; Roh, Byung Suk; Kim, Jae Kyu

    1993-01-01

    Modified biliary gianturco stents were placed in 27 patients with obstructive jaundice. From July 1990 to October 1992, 46 two-seven connected stents of 8-12 mm in diameter (Myungsung Meditech, Seoul, Korea) were placed in 5 patients with benign biliary stricture and 22 patients with malignant biliary stricture in three university hospitals; 12 in Chonbuk National University Hospital, 12 in Wonkwang University Hospital, and 3 in Chonnam National University Hospital. Nineteen were men and eight were women, ranged in age from 34 to 76 years (average, 55 years). The stents were placed percutaneously through a transhepatic approach using a 8.5 Fr. introducing sheath. All stents were placed successfully without any technical failures or procedural morbidity or mortality. All patients complained dull abdominal pain for 1 to 3 days after the stent placement. In a follow-up period of 7-46 weeks, reocclusions were observed in one of the patients with benign stricture (20%) and three of the patients with malignant stricture (16%). Two patients with recurrent jaundice due to the obstruction of the stent were treated with placement of additional stent, one patient was treated with external catheter drainage. Migration of stent occurred in one patient. The application of the expandable biliary metallic stent is suggested as an effective treatment for benign and malignant biliary obstructive jaundice

  7. Modified gianturco biliary stent in benign and malignant obstruction: Results of long-term follow up

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Jin Young; Song, Ho Young; Han, Hyun Young; Han, Young Min; Chung, Gyung Ho; Kim, Chong Soo; Choi, Ki Chul; Roh, Byung Suk; Kim, Jae Kyu [College of Medicine, Chonbuk National University, Chonju (Korea, Republic of)

    1993-05-15

    Modified biliary gianturco stents were placed in 27 patients with obstructive jaundice. From July 1990 to October 1992, 46 two-seven connected stents of 8-12 mm in diameter (Myungsung Meditech, Seoul, Korea) were placed in 5 patients with benign biliary stricture and 22 patients with malignant biliary stricture in three university hospitals; 12 in Chonbuk National University Hospital, 12 in Wonkwang University Hospital, and 3 in Chonnam National University Hospital. Nineteen were men and eight were women, ranged in age from 34 to 76 years (average, 55 years). The stents were placed percutaneously through a transhepatic approach using a 8.5 Fr. introducing sheath. All stents were placed successfully without any technical failures or procedural morbidity or mortality. All patients complained dull abdominal pain for 1 to 3 days after the stent placement. In a follow-up period of 7-46 weeks, reocclusions were observed in one of the patients with benign stricture (20%) and three of the patients with malignant stricture (16%). Two patients with recurrent jaundice due to the obstruction of the stent were treated with placement of additional stent, one patient was treated with external catheter drainage. Migration of stent occurred in one patient. The application of the expandable biliary metallic stent is suggested as an effective treatment for benign and malignant biliary obstructive jaundice.

  8. New expandable metallic stents: An experimental study in vessels of dogs

    International Nuclear Information System (INIS)

    Song, Ho Young; Lee, Jung Min; Chung, Jin Young; Chung, Gyung Ho; Kim, Bog Yi; Kuh, Ja Houng

    1992-01-01

    Three-types of expandable metallic stents were constructed to evaluate the differences between the stents: one, formed in a cylindrical zigzag pattern wth stainless steel wire (Gianturco stent), another, made by coating the Gianturco stent with silicone rubber (Silicone stent), the third, made by coating the Gianturco stent with 24 carat gold (Gold stent) for tissue acceptance. A total of 69 stents (each 23 stents of Gianturco, Silicone, and Gold stents) of 8-12 mm in diameter and 20 mm long were placed into normal abdominal aorta, inferior vena cava and lilac artery of nine adults dogs for 2 weeks to 11 months. It was more difficult to introduce Silicone stent into an introducing sheath than Gianturco or Gold stent due to the thickness of silicone rubber. Four Gianturco stents and three Silicone stents showed migration but Gold stent did not. Luminal narrowing or occlusion was noted in 3 Silicone stents. In 2 Gianturco stents, and in 1 Gold stent. Neointimal proliferation over the stent wires was more rapid and even in Gold stent than Silicone or Gianturco stent. Although further study is needed, Gold stent seems to be better than Gianturco or Silicone stent as an endovascular graft material

  9. New expandable metallic stents: An experimental study in vessels of dogs

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Lee, Jung Min; Chung, Jin Young; Chung, Gyung Ho; Kim, Bog Yi; Kuh, Ja Houng [Chunbuk National University Medical School, Chunju (Korea, Republic of)

    1992-07-15

    Three-types of expandable metallic stents were constructed to evaluate the differences between the stents: one, formed in a cylindrical zigzag pattern wth stainless steel wire (Gianturco stent), another, made by coating the Gianturco stent with silicone rubber (Silicone stent), the third, made by coating the Gianturco stent with 24 carat gold (Gold stent) for tissue acceptance. A total of 69 stents (each 23 stents of Gianturco, Silicone, and Gold stents) of 8-12 mm in diameter and 20 mm long were placed into normal abdominal aorta, inferior vena cava and lilac artery of nine adults dogs for 2 weeks to 11 months. It was more difficult to introduce Silicone stent into an introducing sheath than Gianturco or Gold stent due to the thickness of silicone rubber. Four Gianturco stents and three Silicone stents showed migration but Gold stent did not. Luminal narrowing or occlusion was noted in 3 Silicone stents. In 2 Gianturco stents, and in 1 Gold stent. Neointimal proliferation over the stent wires was more rapid and even in Gold stent than Silicone or Gianturco stent. Although further study is needed, Gold stent seems to be better than Gianturco or Silicone stent as an endovascular graft material.

  10. Gianturco-Rösch Z stents in tracheobronchial stenoses.

    Science.gov (United States)

    Petersen, B D; Uchida, B T; Barton, R E; Keller, F S; Rösch, J

    1995-01-01

    To evaluate expandable metallic Gianturco-Rösch Z (GRZ) stents for treatment of benign and malignant tracheobronchial stenoses. Six patients, ages 45-73 years, were treated for severe dyspnea with placement of GRZ stents. Three patients had benign tracheal lesions (one tracheomalacia, two postoperative) and received uncovered GRZ stents. Three patients had malignant stenoses at the level of the carina; one received an uncovered stent and the other two received silicone-covered GRZ stents. Two patients with benign lesions responded well to stent placement. One was asymptomatic for a year and then was lost to follow-up; the other improved substantially but died of end-stage lung disease 5 months after stent placement. A third patient with a benign high tracheal lesion did poorly; symptoms recurred secondary to inferior migration of a stent, which was removed surgically at 4 months. All patients with malignant lesions improved symptomatically after stent placement and remained without significant dyspnea until death (from 1 to 6 months). Expandable GRZ stents are promising devices for treatment of benign lesions and offer effective palliation of malignant tracheobronchial stenoses.

  11. Expandable metallic stents: An experimental study in the nasolacrimal systems of dogs

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Lee, Jeong Min; Han, Young Min; Hwang, Eui Il; Chung, Gyung Ho; Shon, Myung Hee; Kim, Chong Soo; Choi, Ki Chul [Chonbuk National University Medical School, Chonju(Korea, Republic of)

    1993-11-15

    Balloon dacryocystoplasty has been reported to be a safe, easy and effective nonoperative treatment for nasolacrimal stenosis. The results were not encouraging, however, because of its high failure and recurrence rates. To evaluate the feasibility of using modified Gianturco expandable metallic stents for maintenance of the dilated nasolacrimal system(NLS), 20 stents of 3 mm in diameter and 10 mm long were placed in 20 nasolacrimal ducts of 10 dogs for 1 month to 10 months. It was more difficult to introduce the stents into the proximal portion(A) of the NLS than into the distal portion(B) due to the narrow and bony canal of the A portion. Twenty stents showed no migration in follow-up studies of up to 10 months. One complete occlusion occurred in a stent placed in A portion. Autopsy studies showed stents were covered with epithelium within 2 months after placement. Our experience suggest that the placement of Gianturco self-expandable stents may be a useful method of dilating and maintaining the luminal diameter of the NLS, although care must be taken to select the proper stent size.

  12. Expandable metallic stents: An experimental study in the nasolacrimal systems of dogs

    International Nuclear Information System (INIS)

    Song, Ho Young; Lee, Jeong Min; Han, Young Min; Hwang, Eui Il; Chung, Gyung Ho; Shon, Myung Hee; Kim, Chong Soo; Choi, Ki Chul

    1993-01-01

    Balloon dacryocystoplasty has been reported to be a safe, easy and effective nonoperative treatment for nasolacrimal stenosis. The results were not encouraging, however, because of its high failure and recurrence rates. To evaluate the feasibility of using modified Gianturco expandable metallic stents for maintenance of the dilated nasolacrimal system(NLS), 20 stents of 3 mm in diameter and 10 mm long were placed in 20 nasolacrimal ducts of 10 dogs for 1 month to 10 months. It was more difficult to introduce the stents into the proximal portion(A) of the NLS than into the distal portion(B) due to the narrow and bony canal of the A portion. Twenty stents showed no migration in follow-up studies of up to 10 months. One complete occlusion occurred in a stent placed in A portion. Autopsy studies showed stents were covered with epithelium within 2 months after placement. Our experience suggest that the placement of Gianturco self-expandable stents may be a useful method of dilating and maintaining the luminal diameter of the NLS, although care must be taken to select the proper stent size

  13. Gianturco metallic biliary stent in malignant biliary obstruction: results of follow-up in dead patients

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Byung Suk; Kim, Chan Soo; Lee, Kyung Soo; Choi, See Sung; Won, Jong Jin; Kim, Haak Cheul; Chae, Kwon Mook [Wonkwang University School of Medicine, Iri (Korea, Republic of)

    1994-04-15

    In order to study the patency, restenosis, efficacy, and complication of the metallic stent in the course of treatment of malignant biliary obstruction, the results of follow up of the dead patients after stent insertion were reviewed. Self-expandable Gianturco metallic stent with 10-mm diameter was successfully inserted in 33 patients: 10 with Klatskin tumor, 7 with common bile duct cancer, 7 with gallbladder cancer, 5 with pancreatic cancer, 2 with recurred stomach cancer, one with periampullary cancer, one with hepatocellular carcinoma. The overall duration of survival and patency of the stents in 33 patients were 5.2 months(1-12 months) and 4.9 months(1-14 months), respectively. Restenosis of metallic stents was found in 9 cases(27%), after 6.1 months in average. Causes of stent occlusion were overgrowing of tumor in 5, overgrowing and ingrowing of tumor in 3, extraductal dislodgement in one case. Two cases of symptomatic cholangitis after stent placement were successfully treated with percutaneous cholecystostomy. Three cases of destruction and migration of metallic stents were found after 6 months. On the basis of our experience, insertion of Gianturco metallic biliary stent is an acceptable treatment method in the malignant biliary obstruction, especially for whom short term survival is expected.

  14. Physical property and MR imaging of self-expandable metallic stents

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    Roh, Hong Gee; Kang, Sung Gwon; Cho, Young Kook; Kim, Hyung Jin; Lim, Myung Kwan; Cho, Soon Gu; Yoh, Kyu Tong; Suh, Chang Hae [Inha Univ., College of Medicine, Seoul (Korea, Republic of)

    1998-09-01

    In order to furnish basic information prior to their use, the physical properties of various self-expandable metallic stents and their MR characteristics were evaluated. Four commercially available self-expandable metallic stents-Gianturco-the Rosch, Hanaro, Memotherm, and Wallstent-were used in this study. For evaluation of the physical properties of each, hoop strengths and changes in radii according to the degrees of longitudinal flexion were compared. Stent characteristics seen on MR images were evaluated by measuring magnetic torque and by comparing images obtained in the vascular phantom using SE T1TI, FSE T2WI, and FMPSPGR sequences. These images were analyzed with special emphasis on artifact size and the apparant shepe of the stent. Hoop strength was greatest in the Gianturco-Rosch stent, followed by the Memotherm, Hanaro, and Wallstent. When flexed in the longitudinal axis, the radius of the Hanaro and Memotherm stent decreased slightly as a larger flexion angle was applied. When this was 90 deg, however, the connection of the Gianturco-Rosch stent collapsed. In contrast, the radius of the Wallstent became larger as a larger flexion angle was applied. At the portal of the MR imaging unit, neither the Memotherm nor Wallstent showed deflection; except for a thin hyperintense rim at both ends, their images were excellent, and the lumina of these stents were also clearly seen. In contrast, the Gianturco-Rosch and Hanaro stent demonstrated large deflexion and showed a severe black-hole artifact. As a result, visualization of the stents themselves and their lumina was impossible. The Gianturco-Rosch stent showed greatrer hoop strength than the others. The Wallstent showed good longitudinal flexibility and was thought to be effective in tortuous vessels. For follow-up after placement, especially when the nonferromagnetic Memotherm and Wallstent are used, MR imaging appears to be safe and useful.=20.

  15. Expandable stents.

    Science.gov (United States)

    Nesbitt, J C; Carrasco, H

    1996-05-01

    tissue is less likely to occur in areas of established scar than in areas of acute inflammation. In circumstances in which it is essential that a stent remain only temporarily, an expandable stent should not be inserted in favor of a silicone stent, which can be removed. In the future, expandable stents may have silicone coverings or may be constructed of materials that facilitate removal. Until that time, expandable stents should be considered permanent and nonremovable. Subtle differences exist among the available stents. Standard is low-profile expandable construction from wire mesh. A relatively minor difference is the slightly wider expansibility of the Gianturco stent, a quality that makes it the best suited of the three stents for lesions that involve tracheomalacia. Perhaps the only major difference between the Wallstent and the Gianturco and Palmaz stents is its better ability to conform to tortuous lesions. In an acutely angled stricture, a Wallstent offers a better opportunity for successful placement than other stents. The filamentous meshwork of the Wallstent allows it to bend and conform better to distorted airways. The Gianturco and Palmaz stents have little longitudinal elasticity, which makes them less effective in a tortuous or highly angulated airway stenosis. Expandable stents have demonstrated their efficacy and exposed their limitations in the treatment of airway stenoses. Refinements in design should help to lessen specific disadvantages and problems. Covered expandable stents, a realistic prospect, have specific advantages over standard expandable stents; they will be removable and prevent tumor ingrowth. Current investigative work with such prostheses for the vascular system may provide the foundation for their investigative use in the airway. In essence, two categories of expandable stents are evolving, covered and uncovered, each having unique features adaptable to the specific clinical needs.

  16. In Vivo Study of Polyurethane-Coated Gianturco-Rosch Biliary Z-Stents

    International Nuclear Information System (INIS)

    Severini, Aldo; Mantero, Sara; Tanzi, Maria Cristina; Cigada, Alberto; Addis, Flaminio; Cozzi, Guido; Salvetti, Monica; Andreola, Salvatore; Motta, Antonella; Regalia, Enrico; Pulvirenti, Andrea; De Pedri, Enrico; Doci, Roberto

    1999-01-01

    Purpose: Prototypes of Gianturco-Rosch Z-stents coated with polycarbonate urethane (PCU) were placed in the biliary tree of pigs, in order to test their biomechanical behavior, stability, and biocompatibility. Methods: The stents were surgically implanted in the common bile duct of three pairs of pigs, which were killed after 1, 3, and 6 months respectively. Explanted livers from pigs of the same race, age, and size were used to provide comparative data. The bile ducts were radiologically and histopathologically examined; the stents were processed and examined by scanning electron microscopy. Results: No complications occurred and the animals showed a normal weight gain. The main bile duct appeared radiologically and macroscopically dilated, but the stents proved to be in place. Histologically, the bile duct epithelium was destroyed, but neither hyperplastic nor inflammatory fibrotic reactions of the wall were evident. Both the metallic structure and the polymeric coating of the stents were intact. A layer of organic material with a maximum thickness of approximately 3 μm was evident on the inner surface of the stents. Conclusion: The present in vivo study demonstrates the biocompatibility, efficacy, and stability of PCU-coated Gianturco-Rosch stents in the biliary environment

  17. Endotracheal expandable metallic stent placement in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Sawada, S; Tanabe, Y; Fujiwara, Y; Koyama, T; Tanigawa, N; Kobayashi, M; Katsube, Y; Nakamura, H [Tottori Univ. School of Medicine, Yonago (Japan). Dept. of Radiology Research Inst. for Microbial Diseases, Osaka (Japan). Dept. of Radiology

    1991-01-01

    Various types of Gianturco zig-zag wire stent were implanted into the tracheas of 4 dogs to define the suitable characteristics of the endotracheal wire stent in these animals. These stents were constructed of 0.45, and 0.33 mm stainless steel wire. The diameter of the fully expanded stents was 3 cm and their lengths were 2, 3, and 4 cm. The 2 cm stent constructed of 0.33 mm wire showed minimum pathologic changes of the trachea of the dog compared to the other stents, and at the same time had a complete covering of ciliated columnar epithelium over the stent surface. (orig.).

  18. Mechanical characteristics of self-expandable metallic stents: in vitro study with three types of stress

    International Nuclear Information System (INIS)

    Lee, Byung Hee; Kim, Kie Hwan; Chin, Soo Yil

    1998-01-01

    To obtain objective and comparable data for mechanical characteristics of self-expandable metallic stents widely used in the treatment of biliary obstruction. The stents tested were the 6 and 8 mm-band Hanaro spiral stent, Gianturco-Rosch Z stent, Wallstent, Ultraflex stent, and Memotherm stent. Each was subjected to three types of load:point, area, and circular. We analyzed their mechanical characteristics (resistance force, expansile force, and elasticity) according to these three types of stress. With regard to point loads, the Memotherm stent showed the highest resistance force and expansile force. The 8 mm-band Hanaro stent showed the lowest resistance force and the Gianturco-Rosch Z stent and Ultraflex stent showed lower expansile force. With regard to area loads, the Ultraflex stent showed the highest resistance force. The 6 mm-band Hanaro stent, Gianturco-Rosch Z stent, and Ultraflex stent showed higher expansile force. The 8 mm-band Hanaro stent showed the lowest value in both resistance force and expansile force. For circular loads, the Memotherm stent showed the highest resistance force and the Ultraflex stent and Wallstent showed lower value. Under all types of stress, the Hanaro stent and Memotherm stent were completely elastic, and the Ultraflex stent and Wallstent showed a wide gap between resistance force and expansile force. In clinical practice, awareness of the mechanical characteristics of each stent might help in choosing the one which is most suitable, according to type of biliary obstruction. =20

  19. Mechanical characteristics of self-expandable metallic stents: in vitro study with three types of stress

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Hee; Kim, Kie Hwan; Chin, Soo Yil [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1998-09-01

    To obtain objective and comparable data for mechanical characteristics of self-expandable metallic stents widely used in the treatment of biliary obstruction. The stents tested were the 6 and 8 mm-band Hanaro spiral stent, Gianturco-Rosch Z stent, Wallstent, Ultraflex stent, and Memotherm stent. Each was subjected to three types of load:point, area, and circular. We analyzed their mechanical characteristics (resistance force, expansile force, and elasticity) according to these three types of stress. With regard to point loads, the Memotherm stent showed the highest resistance force and expansile force. The 8 mm-band Hanaro stent showed the lowest resistance force and the Gianturco-Rosch Z stent and Ultraflex stent showed lower expansile force. With regard to area loads, the Ultraflex stent showed the highest resistance force. The 6 mm-band Hanaro stent, Gianturco-Rosch Z stent, and Ultraflex stent showed higher expansile force. The 8 mm-band Hanaro stent showed the lowest value in both resistance force and expansile force. For circular loads, the Memotherm stent showed the highest resistance force and the Ultraflex stent and Wallstent showed lower value. Under all types of stress, the Hanaro stent and Memotherm stent were completely elastic, and the Ultraflex stent and Wallstent showed a wide gap between resistance force and expansile force. In clinical practice, awareness of the mechanical characteristics of each stent might help in choosing the one which is most suitable, according to type of biliary obstruction. =20.

  20. An experimental study on the influence of the intravascular gianturco type stents on the vascular structures

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Yeon Hyeon [Sejong General Hospital, Bucheon (Korea, Republic of); Park, Jae Hyung; Han, Joon Koo; Han, Man Chung; Kim, Chu Wan [College of Medicine, Seoul National University, Seoul (Korea, Republic of)

    1991-07-15

    Twenty-seven Gianturco-type self-expandable stainless steel intravascular stents were placed into the infrarenal abdominal aortas (n=17) and inferior venae cavae (n=10) in 14 mongrel dogs. In 8 aortas, stents were delivered after balloon catheter-induced denudation of the intima, and in 4 out of the 8 aortas, the stents were also placed into the normal sites to compare the neointimal thickness of the normal and denuded sites. Angiography, light microscopic, and scanning electron microscopic examinations were performed after 1 week (n=1), 2 weeks (n=6), 3 weeks (n=5), and 6 weeks (n=2). The patency rate and thrombosis rate were 100% and 35% in the aortas and 100% and 60% in the inferior venae cavae. The aortic stent wires were covered with thin fibrinous membrane after 1 week. Nearly complete transparent neointimal covering was found in the aortas and caval veins after 2 weeks. There was no significant difference in intimal thickness between the denuded and normal aortas after 2 weeks ({rho} =0.51) and 3 weeks ({rho} =0.56). In 4 dogs with caval vein stents, there was evidence of hemorrhage infarction in the lungs. The thrombosis rate of 12 stents with a stent-artery ratio (SAR) of 1.5 or higher was 41%, while there was no thrombus on the 4 stents with SAR 1.2 or lower, except for 1 specimen after 1 week. It is suggested that stents with SAR 1.2 or lower are more suitable. The high thrombosis rate of the inferior venae cavae may be related with slow blood flow.

  1. The quantification of hemodynamic parameters downstream of a Gianturco Zenith stent wire using newtonian and non-newtonian analog fluids in a pulsatile flow environment.

    Science.gov (United States)

    Walker, Andrew M; Johnston, Clifton R; Rival, David E

    2012-11-01

    Although deployed in the vasculature to expand vessel diameter and improve blood flow, protruding stent struts can create complex flow environments associated with flow separation and oscillating shear gradients. Given the association between magnitude and direction of wall shear stress (WSS) and endothelial phenotype expression, accurate representation of stent-induced flow patterns is critical if we are to predict sites susceptible to intimal hyperplasia. Despite the number of stents approved for clinical use, quantification on the alteration of hemodynamic flow parameters associated with the Gianturco Z-stent is limited in the literature. In using experimental and computational models to quantify strut-induced flow, the majority of past work has assumed blood or representative analogs to behave as Newtonian fluids. However, recent studies have challenged the validity of this assumption. We present here the experimental quantification of flow through a Gianturco Z-stent wire in representative Newtonian and non-Newtonian blood analog environments using particle image velocimetry (PIV). Fluid analogs were circulated through a closed flow loop at physiologically appropriate flow rates whereupon PIV snapshots were acquired downstream of the wire housed in an acrylic tube with a diameter characteristic of the carotid artery. Hemodynamic parameters including WSS, oscillatory shear index (OSI), and Reynolds shear stresses (RSS) were measured. Our findings show that the introduction of the stent wire altered downstream hemodynamic parameters through a reduction in WSS and increases in OSI and RSS from nonstented flow. The Newtonian analog solution of glycerol and water underestimated WSS while increasing the spatial coverage of flow reversal and oscillatory shear compared to a non-Newtonian fluid of glycerol, water, and xanthan gum. Peak RSS were increased with the Newtonian fluid, although peak values were similar upon a doubling of flow rate. The introduction of the

  2. Expandable metallic stent: experimental and clinical experience in tracheobronchial tree

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Lee, Sang Young; Chung, Jin Young; Han, Young Min; Kim, Jong Soo; Choi, Ki Chul; Hong, Ki Whan; Rhee, Yang Kun [Chonbuk National University Medical School, Jeonju (Korea, Republic of)

    1991-05-15

    To maintain or reestablish an adequate airway in a patient with tracheobronchial narrowing coming from various causes, we constructed self-expanding metallic stents the same way Gianturco did, using them in 2 patients after an experimental study with rabbits. Twenty stents (10mm in diameter fully expanded and 20mm in length) were introduced into the trachea or bronchi of 10 Newzealand rabbits (weight, 2.5-3.0kg) through a 8.5 French Teflon sheath. No difficulties were encountered in the placement of the stents. At follow-up (4-12 weeks), no stent showed migration. Three rabbits died of pneumonia or bronchial perforation. Histologically, mucosal inflammation was noted at the sites of stent placement, and stent wires were covered by proliferated epithelium with intact cilia. During the last 4 months, 2 stents were used in 2 patients, one in a patient with endobronchial tuberculosis (3.0cm in length and 1.0cm in diameter fully expanded) and the other (3.0cm in length and 1.5cm in diameter) in a patient with a subglottic mass. In both patients the stents were successfully placed. Just after the placement of the stents dyspnea subsided in both patients, and there was no mortality or morbidity. These stents seem to be effective in the treatment of tracheobronchial stenosis, tracheomalacia, and airway collapse following tracheal reconstruction.

  3. Expandable metallic stent: experimental and clinical experience in tracheobronchial tree

    International Nuclear Information System (INIS)

    Song, Ho Young; Lee, Sang Young; Chung, Jin Young; Han, Young Min; Kim, Jong Soo; Choi, Ki Chul; Hong, Ki Whan; Rhee, Yang Kun

    1991-01-01

    To maintain or reestablish an adequate airway in a patient with tracheobronchial narrowing coming from various causes, we constructed self-expanding metallic stents the same way Gianturco did, using them in 2 patients after an experimental study with rabbits. Twenty stents (10mm in diameter fully expanded and 20mm in length) were introduced into the trachea or bronchi of 10 Newzealand rabbits (weight, 2.5-3.0kg) through a 8.5 French Teflon sheath. No difficulties were encountered in the placement of the stents. At follow-up (4-12 weeks), no stent showed migration. Three rabbits died of pneumonia or bronchial perforation. Histologically, mucosal inflammation was noted at the sites of stent placement, and stent wires were covered by proliferated epithelium with intact cilia. During the last 4 months, 2 stents were used in 2 patients, one in a patient with endobronchial tuberculosis (3.0cm in length and 1.0cm in diameter fully expanded) and the other (3.0cm in length and 1.5cm in diameter) in a patient with a subglottic mass. In both patients the stents were successfully placed. Just after the placement of the stents dyspnea subsided in both patients, and there was no mortality or morbidity. These stents seem to be effective in the treatment of tracheobronchial stenosis, tracheomalacia, and airway collapse following tracheal reconstruction

  4. The new method of modifying the hydrophobic properties of expanded perlite

    Directory of Open Access Journals (Sweden)

    Vogt Elżbieta

    2017-01-01

    Full Text Available The progressive industrialization and development of the automotive industry is the cause of the increasing demand for chemical products, especially oil products. Unfortunately, during processing, transportation or storage of these products, they get very often into the environment causing pollution. The removal of the results of accidents is still a current problem. The techniques which employ various types of sorbents deserve special attention among the several methods of eliminating the effects of pollutions. Moreover, expanded hydrophobic perlite is an interesting material among sorbents which are used on a large scale. The new method of modifying the hydrophobic properties of expanded perlite, with the use of solutions of stearic acid in organic solvents, was presented. The perlite that was used in research was produced by the PerliPol registered partnership in Bełchatów. Hydrophobic properties of the obtained materials were determined on the basis of the results achieved due to the modified film flotation method, “floating on water” test and on the basis of the value of water retention for individual samples. All grain fractions of perlite obtained hydrophobic properties which were better than or comparable to the hydrophobic properties of the HydroPerl (PerlPol commercial material used to remove petroleum product pollution. The hydrophobization process significantly improved the adsorption capacity of modified perlite to petroleum product pollution.

  5. Implantation of modified Y-shaped self-expandable stent for the treatment of stenosis of gastroenteric stoma: preliminary results in five cases

    International Nuclear Information System (INIS)

    Wu Gang; Si Jiangtao; Han Xinwei; Jiao Dechao; Ding Pengxu; Fu Mingti; Li Zhen; Ma Ji

    2010-01-01

    Objective To investigate the feasibility and therapeutic effect of stenting therapy by using modified Y-shaped self-expandable metal stent for the stenosis of gastroenteric stoma. Methods: According to the particular anatomic structures and the pathological features of the narrowed gastroenteric stoma,the authors designed a modified Y-shaped self-expandable metal stent. Under the fluoroscopic guidance, implantation of modified Y-shaped self-expandable metal stent was performed in 5 patients with narrowed gastroenteric stoma. The technical safety and the clinical results were evaluated. Results: The modified Y-shaped self-expandable metal stent was successfully implanted with one procedure in all five patients. After the implantation the symptoms such as nausea, vomiting, abdominal distension were promptly relieved, and the patients' living quality was markedly improved. Conclusion: The stenting therapy with modified Y-shaped self-expandable metal stent can rapidly relieve the stenosis of gastroenteric stoma once for all. The technique is feasible and the short-term effect is reliable, therefore, it is worth popularizing this therapy in clinical practice. (authors)

  6. Membranous obstruction of inferior vena cava(MOIVC): treatment with percutaneous transluminal angioplasty(PTA) and self expandable metallic stent

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ki Yeol; Kim, Baek Hyun; Cha, In Ho; Lee, Nam Joon; Kim, Yun Hwan; Kim, Jung Hyuk [College of Medicine, Korea University, Seoul (Korea, Republic of)

    1994-03-15

    Percutaneous transluminal angioplasty(PTA) with a balloon catheter is a standard method of treatment for membranous obstruction of inferior vena cava(MOIVC). But, correct therapeutic approach has not been established for MOIVC patients whose lesion is associated with extensive thrombotic IVC occlusion. We tried to treat MOIVC associated with or without thrombus. We treated 13 cases of MOIVC(associated with thrombus in 7 cases, no thrombus in 6 cases) with PTA, thrombolysis and self-expandable metallic stents. PTA was successful in 8 cases, but failed in 5 cases. The recurred cases were retreated with PTA, but follow-up study revealed recoiling restenosis in 4 cases and intimal hyperplasia in 1 case at previous PTA site which could be overcome with a self-expandable metallic stent. The complication were occurred in 3 cases which were hemothorax, hemopericardium, and hemoperitoneum respectively. However, those were resolved by conservative treatment only. Recanalization and dilatation could be done in MOIVC patients with or without thrombosis for improvement of patient's symptom. Gianturco self-expandable metallic stent is useful in treatment of recurred MOIVC after balloon dilatation and preventing reocclusion of the IVC after PTA.

  7. Evaluation of an expanded case definition for vaccine-modified measles in a school outbreak in South Korea in 2010.

    Science.gov (United States)

    Choe, Young June; Hu, Jae Kyung; Song, Kyung Min; Cho, Heeyeon; Yoon, Hee Sook; Kim, Seung Tae; Lee, Han Jung; Kim, Kisoon; Bae, Geun-Ryang; Lee, Jong-Koo

    2012-01-01

    In this study, we have described the clinical characteristics of vaccine-modified measles to assess the performance of an expanded case definition in a school outbreak that occurred in 2010. The sensitivity, specificity, and the positive and negative predictive values were evaluated. Among 74 cases of vaccine-modified measles, 47 (64%) met the original case definition. Fever and rash were observed in 73% (54/74); fever was the most common (96%, 71/74) presenting symptom, and rash was noted in 77% (57/74) of the cases. The original case definition showed an overall sensitivity of 63.5% and a specificity of 100.0%. The expanded case definition combining fever and rash showed a higher sensitivity (72.9%) but a lower specificity (88.2%) than the original. The presence of fever and one or more of cough, coryza, or conjunctivitis scored the highest sensitivity among the combinations of signs and symptoms (77.0%), but scored the lowest specificity (52.9%). The expanded case definition was sensitive in identifying suspected cases of vaccine-modified measles. We suggest using this expanded definition for outbreak investigation in a closed community, and consider further discussions on expanding the case definition of measles for routine surveillance in South Korea.

  8. The use of self expandable metallic stent in the management of malignant biliary obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Han, Joon Koo; Choi, Byung Ihn; Chung, Jin Wook; Park, Jae Hyung; Han, Gi Seok; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1993-05-15

    Self expandable metallic stent is a good alternative of percutaneous transhepatic biliary drainage because it can eliminate numerous problems caused by external drainage catheter, such as tube dislodgement, bile leakage and psychotic problems. Authors analyzed initial results of self expandable metallic stents used in the patient with malignant biliary obstruction to evaluate the efficacy of the procedure and to find the technical problems in the procedure. Self expandable metallic stents were inserted in 14 patients: three with recurrent stomach cancer: three with gallbladder cancer: seven with Klaskin tumor: one with common duct cancer. Gianturco type stent was used in 9 cases ans Wallstent was used in 2 cases. In remaining three case, both Z-stent and Wallstent were used in the same patient. The average period of follow up was 104 days (4-409 days). In 13 cases, the patency of the bile duct was restored by the stent (technical success: 92.9%). Occlusions of the stent were found in two cases, after two and 13 months, respectively. Causes of failure and stent occlusion were associated duodenal obstruction, tumor overgrowth and shortening of Wallstent. In remaining 11 patients, one patient was lost to follow up an 10 patients did not show recurrent jaundice until death or last follow up. There was no major complication related to the procedure. The insertion of self expandable metallic stent is a safe procedure and can eliminate major disadvantages of PTBD. Overstenting, overlapping and evaluation of associated GI tract obstruction is crucial for obtaining technical success and long-term patency.

  9. The use of self expandable metallic stent in the management of malignant biliary obstruction

    International Nuclear Information System (INIS)

    Han, Joon Koo; Choi, Byung Ihn; Chung, Jin Wook; Park, Jae Hyung; Han, Gi Seok; Han, Man Chung

    1993-01-01

    Self expandable metallic stent is a good alternative of percutaneous transhepatic biliary drainage because it can eliminate numerous problems caused by external drainage catheter, such as tube dislodgement, bile leakage and psychotic problems. Authors analyzed initial results of self expandable metallic stents used in the patient with malignant biliary obstruction to evaluate the efficacy of the procedure and to find the technical problems in the procedure. Self expandable metallic stents were inserted in 14 patients: three with recurrent stomach cancer: three with gallbladder cancer: seven with Klaskin tumor: one with common duct cancer. Gianturco type stent was used in 9 cases ans Wallstent was used in 2 cases. In remaining three case, both Z-stent and Wallstent were used in the same patient. The average period of follow up was 104 days (4-409 days). In 13 cases, the patency of the bile duct was restored by the stent (technical success: 92.9%). Occlusions of the stent were found in two cases, after two and 13 months, respectively. Causes of failure and stent occlusion were associated duodenal obstruction, tumor overgrowth and shortening of Wallstent. In remaining 11 patients, one patient was lost to follow up an 10 patients did not show recurrent jaundice until death or last follow up. There was no major complication related to the procedure. The insertion of self expandable metallic stent is a safe procedure and can eliminate major disadvantages of PTBD. Overstenting, overlapping and evaluation of associated GI tract obstruction is crucial for obtaining technical success and long-term patency

  10. A Novel Method to Generate and Expand Clinical-Grade, Genetically Modified, Tumor-Infiltrating Lymphocytes

    Directory of Open Access Journals (Sweden)

    Marie-Andrée Forget

    2017-08-01

    Full Text Available Following the clinical success achieved with the first generation of adoptive cell therapy (ACT utilizing in vitro expanded tumor-infiltrating lymphocytes (TILs, the second and third generations of TIL ACT are evolving toward the use of genetically modified TIL. TIL therapy generally involves the transfer of a high number of TIL, ranging from 109 to 1011 cells. One of the technical difficulties in genetically modifying TIL, using a retroviral vector, is the ability to achieve large expansion of transduced TIL, while keeping the technique suitable to a Good Manufacturing Practices (GMP environment. Consequently, we developed and optimized a novel method for the efficient production of large numbers of GMP-grade, gene-modified TIL for the treatment of patients with ACT. The chemokine receptor CXCR2 was used as the gene of interest for methodology development. The optimized procedure is currently used in the production of gene-modified TIL for two clinical trials for the treatment of metastatic melanoma at MD Anderson Cancer Center.

  11. Exergy analysis of helium liquefaction systems based on modified Claude cycle with two-expanders

    Science.gov (United States)

    Thomas, Rijo Jacob; Ghosh, Parthasarathi; Chowdhury, Kanchan

    2011-06-01

    Large-scale helium liquefaction systems, being energy-intensive, demand judicious selection of process parameters. An effective tool for design and analysis of thermodynamic cycles for these systems is exergy analysis, which is used to study the behavior of a helium liquefaction system based on modified Claude cycle. Parametric evaluation using process simulator Aspen HYSYS® helps to identify the effects of cycle pressure ratio and expander flow fraction on the exergetic efficiency of the liquefaction cycle. The study computes the distribution of losses at different refrigeration stages of the cycle and helps in selecting optimum cycle pressures, operating temperature levels of expanders and mass flow rates through them. Results from the analysis may help evolving guidelines for designing appropriate thermodynamic cycles for practical helium liquefaction systems.

  12. Characterization and application of expanded graphite modified with phosphoric acid and glucose for the removal of Ni(II) from aqueous solution

    International Nuclear Information System (INIS)

    Jiang, Li; Zhang, Jian; Xu, Xiaoli; Zhang, Jie; Liu, Hai; Guo, Zizhang; Kang, Yan; Li, Yiran; Xu, Jingtao

    2015-01-01

    Highlights: • Glucose and H 3 PO 4 , single or together, were used to modify expanded graphite. • The modified condition was at a low temperature (150 °C). • The properties of EG and the highest adsorption ability modified EG were compared. • G-P-EG has the highest adsorption ability, which is much higher than that of EG. - Abstract: Three kinds of modified expanded graphite (EG), impregnated with phosphoric acid (H 3 PO 4 ) (P-EG), impregnated with glucose (G-EG), and impregnated with H 3 PO 4 and glucose (G-P-EG), were prepared under a low temperature (150 °C). The adsorption capacity of G-P-EG (Q m = 7.016 mg/g) is much higher than original expanded graphite (EG Q m = 0.423 mg/g) and other two kinds of modified expanded graphite (P-EG Q m = 0.770 mg/g; G-EG Q m = 0.507 mg/g). The physicochemical properties of EG and G-P-EG were characterized by N 2 adsorption/desorption, Boehm's titration and X-ray photoelectron spectroscopy (XPS). EG exhibited higher values of BET surface area (11.357 m 2 /g) and total pore volume (0.0303 cm 3 /g) than that of G-P-EG (4.808 m 3 /g and 0.0109 cm 3 /g). However, the results of Bohm's titration and XPS showed that G-P-EG contained more surface oxygen-containing functional groups. The Ni(II) adsorption equilibrium data agreed well with the Langmuir model. And the experimental data of EG and G-P-EG fitted better by pseudo-second order model. Based on the results of batch adsorption experiments and XPS analysis, there were several possible mechanisms for Ni(II) adsorption on the G-P-EG, including chemical adsorption, cation exchange, electrostatic attraction and surface complication.

  13. Silicone covered vs. Non- covered endotracheal self expandable metallic stent: An experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Do, Young Soo; Lee, Byung Hee; Kim, Soo Ah; Kim, Kie Hwan; Chin, Soo Yil; Cho, Kyung Ja; Cho, Dae Soon [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1994-10-15

    To evaluate pathologic changes of the trachea and the lung after insertion of silicone covered and non covered Gianturco stent in the trachea of dog. Silicone covered(covered) and non covered(bare) Gianturco stent, six in each, were inserted into the tracheal lumen of six consecutive dogs. After 1-10 weeks observation, the dogs were sacrificed and their tracheas and lungs were examined grossly and histopathologically. Serial chest radiographs were performed to evaluate pneumonia and stent migration every 3-5 days. Pneumonia was observed in one of bare stent group and five of covered stent group. Stent migration was noted in three of covered stent group. In bare stent group, the epithelium of the trachea was markedly thickened by hyperplasia and stent was covered by granulation tissue from 6 weeks after stent insertion. Inflammation was focal at contact site between the stent and the trachea. In covered stent group, the epithelium was denuded at multiple areas and there were multifocal squamous metaplasia of the mucosa. Inflammatory reaction of the trachea was diffuse. Inflammatory reaction was more severe and stent migration was more frequent in covered stent group. The use of covered stent in the trachea should be studied further.

  14. Endovascular treatment of intrahepatic inferior vena cava obstruction from malignant hepatocellular tumor thrombus utilizing Luminexx self-expanding nitinol stents

    International Nuclear Information System (INIS)

    Stambo, Glenn W.; Leto, John; George, Christopher; Van Epps, Kelly; Woeste, Troy; Berlet, Mathew

    2008-01-01

    Inferior vena cava (IVC) obstruction is a well-described clinical entity. Most IVC obstructions from malignant neoplasms are a direct result of tumor compression [Oviedo J, Cerda S. Vascular invasion by hepatocellular carcinoma. Arch Pathol Lab Med 2001;125: 454-5; Furui S, Sawada S, et al. Gianturco stent placement in malignant caval obstruction: analysis of factors for predicting the outcome. Radiology 1995;195:147-52; Fletcher WS, Lakin PC, et al. Results of treatment of inferior vena cava syndrome with expandable metallic stents. Arch Surg 1998;133:935-8]. The symptoms of IVC obstruction include progressive ascites, scrotal edema and lower body edema. These constellations of symptoms are described as IVC syndrome and are devastating to a patient with end-stage cancer. We describe a palliative therapy utilizing Luminexx nitinol self-expanding stents to treat intracaval hepatoma thrombus obstructing the IVC. The procedure is rapidly performed, technically reliable, and has essentially no morbidity or mortality. This procedure can be performed in the interventional radiology suite with excellent results resolving the IVC syndrome soon after placement of the stents. We believe endovascular stenting as an excellent palliative therapy for patients with IVC syndrome and should be the treatment of choice for caval obstructions due to intraluminal tumor thrombus

  15. Endovascular treatment of intrahepatic inferior vena cava obstruction from malignant hepatocellular tumor thrombus utilizing Luminexx self-expanding nitinol stents

    Energy Technology Data Exchange (ETDEWEB)

    Stambo, Glenn W. [Division of Vascular and Interventional Radiology, Department of Radiology, St. Joseph' s Hospital and Medical Center, 4516 North Armenia Avenue, Tampa, FL 33603 (United States)], E-mail: xraydoc2@yahoo.com; Leto, John [Division of Vascular and Interventional Radiology, Department of Radiology, St. Joseph' s Hospital and Medical Center, 3001 W. Dr. Martin Luther King Jr. Blvd., Tampa, FL 33607 (United States); George, Christopher [Department of Hematology and Oncology, St. Joseph' s Hospital and Medical Center, 4301 W. Habana Avenue, Suite 1, Tampa, FL 33607 (United States); Van Epps, Kelly; Woeste, Troy; Berlet, Mathew [Division of Vascular and Interventional Radiology, Department of Radiology, St. Joseph' s Hospital and Medical Center, 4516 North Armenia Avenue, Tampa, FL 33603 (United States)

    2008-05-15

    Inferior vena cava (IVC) obstruction is a well-described clinical entity. Most IVC obstructions from malignant neoplasms are a direct result of tumor compression [Oviedo J, Cerda S. Vascular invasion by hepatocellular carcinoma. Arch Pathol Lab Med 2001;125: 454-5; Furui S, Sawada S, et al. Gianturco stent placement in malignant caval obstruction: analysis of factors for predicting the outcome. Radiology 1995;195:147-52; Fletcher WS, Lakin PC, et al. Results of treatment of inferior vena cava syndrome with expandable metallic stents. Arch Surg 1998;133:935-8]. The symptoms of IVC obstruction include progressive ascites, scrotal edema and lower body edema. These constellations of symptoms are described as IVC syndrome and are devastating to a patient with end-stage cancer. We describe a palliative therapy utilizing Luminexx nitinol self-expanding stents to treat intracaval hepatoma thrombus obstructing the IVC. The procedure is rapidly performed, technically reliable, and has essentially no morbidity or mortality. This procedure can be performed in the interventional radiology suite with excellent results resolving the IVC syndrome soon after placement of the stents. We believe endovascular stenting as an excellent palliative therapy for patients with IVC syndrome and should be the treatment of choice for caval obstructions due to intraluminal tumor thrombus.

  16. Characterization and application of expanded graphite modified with phosphoric acid and glucose for the removal of Ni(II) from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Li [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Zhang, Jian, E-mail: zhangjian00@sdu.edu.cn [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Xu, Xiaoli [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Zhang, Jie [Shandong Experimental High School, Jinan 250100 (China); Liu, Hai; Guo, Zizhang; Kang, Yan; Li, Yiran [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Xu, Jingtao [School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan 250100 (China)

    2015-12-01

    Highlights: • Glucose and H{sub 3}PO{sub 4}, single or together, were used to modify expanded graphite. • The modified condition was at a low temperature (150 °C). • The properties of EG and the highest adsorption ability modified EG were compared. • G-P-EG has the highest adsorption ability, which is much higher than that of EG. - Abstract: Three kinds of modified expanded graphite (EG), impregnated with phosphoric acid (H{sub 3}PO{sub 4}) (P-EG), impregnated with glucose (G-EG), and impregnated with H{sub 3}PO{sub 4} and glucose (G-P-EG), were prepared under a low temperature (150 °C). The adsorption capacity of G-P-EG (Q{sub m} = 7.016 mg/g) is much higher than original expanded graphite (EG Q{sub m} = 0.423 mg/g) and other two kinds of modified expanded graphite (P-EG Q{sub m} = 0.770 mg/g; G-EG Q{sub m} = 0.507 mg/g). The physicochemical properties of EG and G-P-EG were characterized by N{sub 2} adsorption/desorption, Boehm's titration and X-ray photoelectron spectroscopy (XPS). EG exhibited higher values of BET surface area (11.357 m{sup 2}/g) and total pore volume (0.0303 cm{sup 3}/g) than that of G-P-EG (4.808 m{sup 3}/g and 0.0109 cm{sup 3}/g). However, the results of Bohm's titration and XPS showed that G-P-EG contained more surface oxygen-containing functional groups. The Ni(II) adsorption equilibrium data agreed well with the Langmuir model. And the experimental data of EG and G-P-EG fitted better by pseudo-second order model. Based on the results of batch adsorption experiments and XPS analysis, there were several possible mechanisms for Ni(II) adsorption on the G-P-EG, including chemical adsorption, cation exchange, electrostatic attraction and surface complication.

  17. R[iological interventions in central venous obstructions. Dilatation, stent-implantation and thrombolysis

    International Nuclear Information System (INIS)

    Mathias, K.; Jaeger, H.; Willaschek, J.; Theophil, B.

    1998-01-01

    Purpose: Venous congestion of the superior or inferior caval system has to be considered as a medical emergency. The results of various recanalization procedures and their utility are analyzed. Patients and methods: 176 patients with superior and 28 with inferior caval obstruction were treated with Gianturco-Z (n=39) and Wall Stents (n=207) respectively. Balloon venoplasty was performed prior to stent implanation. In 27 cases, local thrombolysis with urokinase was employed. Results: Interventional procedures were succesful in 198 and without success in 6 patients. In most patients, symptoms were relieved during or early after recanalization. No major complications were found. Discussion: Balloon angioplasty with stent placement and local thrombolysis are successful in the treatment of superior and inferior caval obstruction. Self-expanding Wallstents are superior to Gianturco-Z-stents. Oncologists should be m[e familiar with this type of treatment. (orig.) [de

  18. Characterization and application of expanded graphite modified with phosphoric acid and glucose for the removal of Ni(II) from aqueous solution

    Science.gov (United States)

    Jiang, Li; Zhang, Jian; Xu, Xiaoli; Zhang, Jie; Liu, Hai; Guo, Zizhang; Kang, Yan; Li, Yiran; Xu, Jingtao

    2015-12-01

    Three kinds of modified expanded graphite (EG), impregnated with phosphoric acid (H3PO4) (P-EG), impregnated with glucose (G-EG), and impregnated with H3PO4 and glucose (G-P-EG), were prepared under a low temperature (150 °C). The adsorption capacity of G-P-EG (Qm = 7.016 mg/g) is much higher than original expanded graphite (EG Qm = 0.423 mg/g) and other two kinds of modified expanded graphite (P-EG Qm = 0.770 mg/g; G-EG Qm = 0.507 mg/g). The physicochemical properties of EG and G-P-EG were characterized by N2 adsorption/desorption, Boehm's titration and X-ray photoelectron spectroscopy (XPS). EG exhibited higher values of BET surface area (11.357 m2/g) and total pore volume (0.0303 cm3/g) than that of G-P-EG (4.808 m3/g and 0.0109 cm3/g). However, the results of Bohm's titration and XPS showed that G-P-EG contained more surface oxygen-containing functional groups. The Ni(II) adsorption equilibrium data agreed well with the Langmuir model. And the experimental data of EG and G-P-EG fitted better by pseudo-second order model. Based on the results of batch adsorption experiments and XPS analysis, there were several possible mechanisms for Ni(II) adsorption on the G-P-EG, including chemical adsorption, cation exchange, electrostatic attraction and surface complication.

  19. Synthesis and CO2 adsorption study of modified MOF-5 with multi-wall carbon nanotubes and expandable graphite

    International Nuclear Information System (INIS)

    Ullah, Sami; Bustam, M. A.; Shariff, A. M.; Elkhalifah, Ali E. I.; Murshid, G.; Riaz, Nadia

    2014-01-01

    MOF-5 was synthesized by solvothermal method and its reactivation under anhydrous conditions. This research is conducted to investigate the effect of MOF-5 and MOF-5 modified with multi-wall carbon nanotubes (MWCNTs) and expandable graphite (EG) on the performance of CO 2 adsorption. The synthesized MOFs were characterized using Field emission scanning electron microscopy (FESEM) for surface morphology, Thermogravimetric analysis (TGA) for thermal stability, X-ray diffraction (XRD) for crystals plane, Brunauer-Emmet-Teller (BET) for surface area and CO 2 adsorption. The result had showed that the modified MOF-5 enhanced the CO 2 adsorption compared to the pure MOF-5. The increment in the CO 2 uptake capacities of MOF materials was attributed to the decrease in the pore size and enhancement of micropore volume of MOF-5 by multi-walled carbon nanotube and EG incorporation. The BET surface area of the synthesized MOF-5@MWCNTs is more than MOF-5. The CO 2 sorption capacities of MOF-5 and MOF-5@MWCNTs were observed to increase from 0.00008 to 0.00048 mol g-1 at 298 K and 1 bar. The modified MOF-5@MWCNTs resulted in the highest CO 2 adsorption followed by the modified MOF-5@ EG and lastly, MOF-5

  20. Geothermal ORC Systems Using Large Screw Expanders

    OpenAIRE

    Biederman, Tim R.; Brasz, Joost J.

    2014-01-01

    Geothermal ORC Systems using Large Screw Expanders Tim Biederman Cyrq Energy Abstract This paper describes a low-temperature Organic Rankine Cycle Power Recovery system with a screw expander a derivative of developed of Kaishan's line of screw compressors, as its power unit. The screw expander design is a modified version of its existing refrigeration compressor used on water-cooled chillers. Starting the ORC development program with existing refrigeration screw compre...

  1. Electrochemical Determination of Brilliant Blue and Tartrazine Based on an Ionic Liquid-Modified Expanded Graphite Paste Electrode.

    Science.gov (United States)

    Wang, Wenchang; Chen, Ye; Zhang, Jing; Wang, Xue; Chen, Zhidong

    2015-01-01

    A sensitive electrochemical method was developed for the simultaneous determination of Brilliant Blue (BB) and tartrazine (Tz) using an ionic liquid-modified expanded graphite paste electrode (IL-EGPE). The IL-EGPE was prepared by mixing ionic liquid-expanded graphite composite (IL-EG) with solid paraffin. Compared with the EGPE, the IL-EGPE remarkably enhanced the electrocatalytic oxidation signals of BB and Tz. Under optimal experimental conditions, the designed IL-EGPE exhibited wide linear responses to BB and Tz ranging from 5.0×10(-9) to 4.0×10(-6) M and 1.0×10(-8) to 1.0×10(-6) M, respectively. The detection limits for BB and Tz were 2.0×10(-9) M (1.6 ng/mL) and 3.3×10(-9) M (1.8 ng/mL) at an S/N of 3, respectively. This electrode showed good reproducibility, stability, and reusability. The proposed method was successfully applied in the simultaneous determination of BB and Tz in a soft drink with satisfactory results.

  2. Synthesis and CO{sub 2} adsorption study of modified MOF-5 with multi-wall carbon nanotubes and expandable graphite

    Energy Technology Data Exchange (ETDEWEB)

    Ullah, Sami, E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Bustam, M. A., E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Shariff, A. M., E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Elkhalifah, Ali E. I., E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Murshid, G., E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Riaz, Nadia, E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com [Research Center for Carbon Dioxide Capture, Dept. of Chemical Engineering, Universiti Teknologi PETRONAS, Bandar Sri Iskandar, Tronoh 31750 Perak (Malaysia)

    2014-10-24

    MOF-5 was synthesized by solvothermal method and its reactivation under anhydrous conditions. This research is conducted to investigate the effect of MOF-5 and MOF-5 modified with multi-wall carbon nanotubes (MWCNTs) and expandable graphite (EG) on the performance of CO{sub 2} adsorption. The synthesized MOFs were characterized using Field emission scanning electron microscopy (FESEM) for surface morphology, Thermogravimetric analysis (TGA) for thermal stability, X-ray diffraction (XRD) for crystals plane, Brunauer-Emmet-Teller (BET) for surface area and CO{sub 2} adsorption. The result had showed that the modified MOF-5 enhanced the CO{sub 2} adsorption compared to the pure MOF-5. The increment in the CO{sub 2} uptake capacities of MOF materials was attributed to the decrease in the pore size and enhancement of micropore volume of MOF-5 by multi-walled carbon nanotube and EG incorporation. The BET surface area of the synthesized MOF-5@MWCNTs is more than MOF-5. The CO{sub 2} sorption capacities of MOF-5 and MOF-5@MWCNTs were observed to increase from 0.00008 to 0.00048 mol g-1 at 298 K and 1 bar. The modified MOF-5@MWCNTs resulted in the highest CO{sub 2} adsorption followed by the modified MOF-5@ EG and lastly, MOF-5.

  3. Adsorption and regeneration of expanded graphite modified by CTAB-KBr/H3PO4 for marine oil pollution.

    Science.gov (United States)

    Xu, Congbin; Jiao, Chunlei; Yao, Ruihua; Lin, Aijun; Jiao, Wentao

    2018-02-01

    The cleaning-up of viscous oil spilled in ocean is a global challenge, especially in Bohai, due to its slow current movement and poor self-purification capacity. Frequent oil-spill accidents not only cause severe and long-term damages to marine ecosystems, but also lead to a great loss of valuable resources. To eliminate the environmental pollution of oil spills, an efficient and environment-friendly oil-recovery approach is necessary. In this study, 1 expanded graphite (EG) modified by CTAB-KBr/H 3 PO 4 was synthesized via composite intercalation agents of CTAB-KBr and natural flake graphite, followed by the activation of phosphoric acid at low temperature. The resultant modified expanded graphite (M-EG) obtained an interconnected and continuous open microstructure with lower polarity surface, more and larger pores, and increased surface hydrophobicity. Due to these characteristics, M-EG exhibited a superior adsorption capacity towards marine oil. The saturated adsorption capacities of M-EG were as large as 7.44  g/g for engine oil, 6.12 g/g for crude oil, 5.34 g/g for diesel oil and 4.10 g/g for gasoline oil in 120min, exceeding the capacity of pristine EG. Furthermore, M-EG maintained good removal efficiency under different adsorption conditions, such as temperature, oil types, and sodium salt concentration. In addition, oils sorbed into M-EG could be recovered either by a simple compression or filtration-drying treatment with a recovery ratio of 58-83%. However, filtration-drying treatment shows better performance in preserving microstructures of M-EG, which ensures the adsorbents can be recycled several times. High removal capability, fast adsorption efficiency, excellent stability and good recycling performance make M-EG an ideal candidate for treating marine oil pollution in practical application. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Staged abdominal closure with intramuscular tissue expanders and modified components separation technique of a giant incisional hernia after repair of a ruptured omphalocele

    Directory of Open Access Journals (Sweden)

    Yukihiro Tatekawa

    2016-07-01

    Full Text Available In patients with omphalocele, several different techniques are performed for repair of the abdominal wall defect. We present the case of a staged abdominal closure of a giant incisional hernia after repair of a ruptured omphalocele. At birth, skin flap coverage associated with silo formation occurred, but the abdominal wall defect remained, resulting in a giant abdominal hernia. To expand the layers of the abdominal wall, tissue expanders were placed between the bilateral internal oblique and transverses abdominis muscles. Postoperatively, a modified components separation technique was performed. The abdominal wall was closed in the midline. Upon closure of the skin in the midline, bilateral relaxing incisions were performed, covering the remaining defect with artificial dermis. At the age of one year and 7 months, the patient had no recurrent incisional hernia nor any wound complications.

  5. Nitrogen expander cycles for large capacity liquefaction of natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Ho-Myung; Park, Jae Hoon; Gwak, Kyung Hyun [Hong Ik University, Department of Mechanical Engineering, Seoul, 121-791 (Korea, Republic of); Choe, Kun Hyung [Korea Gas Corporation, Incheon, 406-130 (Korea, Republic of)

    2014-01-29

    Thermodynamic study is performed on nitrogen expander cycles for large capacity liquefaction of natural gas. In order to substantially increase the capacity, a Brayton refrigeration cycle with nitrogen expander was recently added to the cold end of the reputable propane pre-cooled mixed-refrigerant (C3-MR) process. Similar modifications with a nitrogen expander cycle are extensively investigated on a variety of cycle configurations. The existing and modified cycles are simulated with commercial process software (Aspen HYSYS) based on selected specifications. The results are compared in terms of thermodynamic efficiency, liquefaction capacity, and estimated size of heat exchangers. The combination of C3-MR with partial regeneration and pre-cooling of nitrogen expander cycle is recommended to have a great potential for high efficiency and large capacity.

  6. Nitrogen expander cycles for large capacity liquefaction of natural gas

    Science.gov (United States)

    Chang, Ho-Myung; Park, Jae Hoon; Gwak, Kyung Hyun; Choe, Kun Hyung

    2014-01-01

    Thermodynamic study is performed on nitrogen expander cycles for large capacity liquefaction of natural gas. In order to substantially increase the capacity, a Brayton refrigeration cycle with nitrogen expander was recently added to the cold end of the reputable propane pre-cooled mixed-refrigerant (C3-MR) process. Similar modifications with a nitrogen expander cycle are extensively investigated on a variety of cycle configurations. The existing and modified cycles are simulated with commercial process software (Aspen HYSYS) based on selected specifications. The results are compared in terms of thermodynamic efficiency, liquefaction capacity, and estimated size of heat exchangers. The combination of C3-MR with partial regeneration and pre-cooling of nitrogen expander cycle is recommended to have a great potential for high efficiency and large capacity.

  7. Nitrogen expander cycles for large capacity liquefaction of natural gas

    International Nuclear Information System (INIS)

    Chang, Ho-Myung; Park, Jae Hoon; Gwak, Kyung Hyun; Choe, Kun Hyung

    2014-01-01

    Thermodynamic study is performed on nitrogen expander cycles for large capacity liquefaction of natural gas. In order to substantially increase the capacity, a Brayton refrigeration cycle with nitrogen expander was recently added to the cold end of the reputable propane pre-cooled mixed-refrigerant (C3-MR) process. Similar modifications with a nitrogen expander cycle are extensively investigated on a variety of cycle configurations. The existing and modified cycles are simulated with commercial process software (Aspen HYSYS) based on selected specifications. The results are compared in terms of thermodynamic efficiency, liquefaction capacity, and estimated size of heat exchangers. The combination of C3-MR with partial regeneration and pre-cooling of nitrogen expander cycle is recommended to have a great potential for high efficiency and large capacity

  8. Performance research on modified KCS (Kalina cycle system) 11 without throttle valve

    International Nuclear Information System (INIS)

    He, Jiacheng; Liu, Chao; Xu, Xiaoxiao; Li, Yourong; Wu, Shuangying; Xu, Jinliang

    2014-01-01

    Two modified systems based on a KCS (Kalina cycle system) 11 with a two-phase expander to substitute a throttle valve are proposed. The two-phase expander is located between the regenerator and the absorber in the B-modified cycle and between the separator and the regenerator in the C-modified cycle. A thermodynamic performance analysis of both the original KCS 11 and the modified systems is carried out. The optimization of two key parameters (the concentration of working fluid and the temperature of cooling water) is also conducted. It is shown that the two modified cycles have different performance under the investigated conditions. Results also indicate that the C-modified cycle can obtain better thermodynamic effect than the B-modified cycle. The temperature of cooling water plays an important role in improving the system performance. When the cooling water temperature drops from 303 K to 278 K, the C-modified cycle thermal efficiency can be improved by 27%. - Highlights: • Throttling valve is replaced by a two-phase expander to recover the expansion work. • Thermodynamic performance of two modified cycle systems is very different. • The maximum increase of work output by C-modified cycle compared with KCS (Kalina cycle system) 11 is 9.4%. • The ranges of ammonia content of B-modified cycle are rather larger

  9. A modified technique for application of tissue expanders for extremities in burn scars patients

    International Nuclear Information System (INIS)

    Ghalambor, A.

    2007-01-01

    Tissue expansion is considered a major advancement in reconstructive surgery. However, there are limitations to their application in the extremities and carries relatively higher rates of complications. The aim of this study was to propose a modification to this technique and assess the rate of complications with slower rate of expansion. Thirty females (age range 14 to 40) with burn scars in the upper or lower extremity (15 cases in each) were the subjects of this investigation. Various sized rectangular expanders were used and expanded at a rate of 5% of the maximum inflatable size over 20 weeks. All of the cases of expansion completed the procedure uneventfully. In one case that developed necrosis at the edge of the flap, one week after removal of the expander, which was debrided and repaired successfully completed the treatment. Slow expansion method is a useful method which can safely be applied for burn scars in the extremities. (author)

  10. Browsing Your Virtual Library: The Case of Expanding Universe.

    Science.gov (United States)

    Daniels, Wayne; Enright, Jeanne; Mackenzie, Scott

    1997-01-01

    Describes "Expanding Universe: a classified search tool for amateur astronomy," a Web site maintained by the Metropolitan Toronto Reference Library which uses a modified form of the Dewey Decimal Classification to organize a large file of astronomy hotlinks. Highlights include structure, HTML coding, design requirements, and future…

  11. Tunneling in expanding Universe: Euclidean and Hamiltonian approaches

    International Nuclear Information System (INIS)

    Goncharov, A.S.; Linde, A.D.

    1986-01-01

    The theory of the false vacuum decay in de Sitter space and in the inflationary Universe, and also the theory of the Universe creation ''from nothing'' are discussed. This explained why tunneling in the inflationary Universe differs from that in de Sitter space and cannot be exactly homogeneous. It is shown that in several important cases the Euclidean approach should be considerably modified or is absolutely inapplicable for the description of tunneling in the expanding Universe and of the process of the quantum creation of the Universe. The Hamiltonian approach to the theory of tunneling in expanding Universe is developed. The results obtained by this method are compared with the results obtained by the Euclidean approach

  12. ExpandED Options: Learning beyond High School Walls

    Science.gov (United States)

    ExpandED Schools, 2014

    2014-01-01

    Through ExpandED Options by TASC, New York City high school students get academic credit for learning career-related skills that lead to paid summer jobs. Too many high school students--including those most likely to drop out--are bored or see classroom learning as irrelevant. ExpandED Options students live the connection between mastering new…

  13. Transluminal endovascular stent-graft for the treatment of aortic aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Do Yun; Chang, Byung Chul; Shim, Won Heum; Cho, Seung Yun; Chung, Nam Sik; Kwon, Hyuk Moon; Lee, Young Joon; Lee, Jong Tae [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1995-09-15

    The standard treatment for aortic aneurysms is surgical replacement with a prosthetic graft. Currently there is great interest in endoluminal intervention for treatment of aortic aneurysm. The purpose of this study was to evaluate the safety and effectiveness of endoluminally placed Stent-graft for the treatment of aortic aneurysms. Transluminal endovascular Stent-graft placements were attempted in 9 patients with infra-renal aortic aneurysms(n 6), thoracic aortic aneurysm(n = 1), and aortic dissection(n = 2). The endovascular Stent-grafts were custom-designed for each patient and were constructed of self-expandable modified Gianturco Stents covered with polytetrafluroethylene. The Stent-grafts were introduced through a 16-18 French sheath and expanded to 17-30 mm in diameter. The endovascular therapy was performed using a common femoral artery cutdown with local anesthesia. The endovascular Stent-graft deployment was achieved in 7 of 9 patients. Two cases failed deployment of the Stent-graft due to iliac artery stenosis and tortousity. There were complete thrombosis of the thoracic and infra-renal aortic aneurysm surround the Stent-graft in 3 patients, and persistent leak with partial thrombosis in 2. Two patients with aortic dissection were successfully treated by obliteration of entry tears. There were no major complication associated with Stent-graft placement. These preliminary results show that transluminal endovascular Stent-grafts offer great promise and good results. Further investigation is needed to establish its long-term safety and efficacy.

  14. Transluminal endovascular stent-graft for the treatment of aortic aneurysms

    International Nuclear Information System (INIS)

    Lee, Do Yun; Chang, Byung Chul; Shim, Won Heum; Cho, Seung Yun; Chung, Nam Sik; Kwon, Hyuk Moon; Lee, Young Joon; Lee, Jong Tae

    1995-01-01

    The standard treatment for aortic aneurysms is surgical replacement with a prosthetic graft. Currently there is great interest in endoluminal intervention for treatment of aortic aneurysm. The purpose of this study was to evaluate the safety and effectiveness of endoluminally placed Stent-graft for the treatment of aortic aneurysms. Transluminal endovascular Stent-graft placements were attempted in 9 patients with infra-renal aortic aneurysms(n 6), thoracic aortic aneurysm(n = 1), and aortic dissection(n = 2). The endovascular Stent-grafts were custom-designed for each patient and were constructed of self-expandable modified Gianturco Stents covered with polytetrafluroethylene. The Stent-grafts were introduced through a 16-18 French sheath and expanded to 17-30 mm in diameter. The endovascular therapy was performed using a common femoral artery cutdown with local anesthesia. The endovascular Stent-graft deployment was achieved in 7 of 9 patients. Two cases failed deployment of the Stent-graft due to iliac artery stenosis and tortousity. There were complete thrombosis of the thoracic and infra-renal aortic aneurysm surround the Stent-graft in 3 patients, and persistent leak with partial thrombosis in 2. Two patients with aortic dissection were successfully treated by obliteration of entry tears. There were no major complication associated with Stent-graft placement. These preliminary results show that transluminal endovascular Stent-grafts offer great promise and good results. Further investigation is needed to establish its long-term safety and efficacy

  15. Cosmology with modified Newtonian dynamics (MOND)

    NARCIS (Netherlands)

    Sanders, R. H.

    1998-01-01

    It is well known that the application of Newtonian dynamics to an expanding spherical region leads to the correct relativistic expression (the Friedmann equation) for the evolution of the cosmic scalefactor. Here, the cosmological implications of Milgrom's modified Newtonian dynamics (MOND) are

  16. Quark and gluon production from a boost-invariantly expanding color electric field

    Science.gov (United States)

    Taya, Hidetoshi

    2017-07-01

    Particle production from an expanding classical color electromagnetic field is extensively studied, motivated by the early stage dynamics of ultrarelativistic heavy ion collisions. We develop a formalism at one-loop order to compute the particle spectra by canonically quantizing quark, gluon, and ghost fluctuations under the presence of such an expanding classical color background field; the canonical quantization is done in the τ -η coordinates in order to take into account manifestly the expanding geometry. As a demonstration, we model the expanding classical color background field by a boost-invariantly expanding homogeneous color electric field with lifetime T , for which we obtain analytically the quark and gluon production spectra by solving the equations of motion of QCD nonperturbatively with respect to the color electric field. In this paper we study (i) the finite lifetime effect, which is found to modify significantly the particle spectra from those expected from the Schwinger formula; (ii) the difference between the quark and gluon production; and (iii) the quark mass dependence of the production spectra. Implications of these results to ultrarelativistic heavy ion collisions are also discussed.

  17. Second Generation Self-Inflating Tissue Expanders: A Two-Year Experience

    Directory of Open Access Journals (Sweden)

    Jamal Omran Al Madani

    2014-01-01

    Full Text Available Background. Tissue expansion is a well-established surgical technique that produces an additional amount of normal skin to cover a defect. This technique is appealing because the skin quality and color are from the patient’s own. The widely used injectable expanders are of great reliability but carry the disadvantage of being painful during injection and most of the time require multiple clinic visits. So the idea of self-inflation became attractive and hydrogel expanders were developed and became widely known for being painless during clinic visit and decrease number of visits. The first generation expanders were modified by adding an enclosing plastic shell to decrease the unopposed expansion that occurred in the first generation expanders, which lead to pressure necrosis of the skin flaps. This made it an attractive option for tissue expansion in children and some adult patients. Patients, Materials, and Methods. Charts of 17 patients were retrospectively reviewed, all of them had second generation self-inflating expanders implanted over a 2-year period for one of two purposes, the treatment of giant nevi or burn scars. Results. Fifteen patients were females and 2 were males. The indication was large burn scar in 14 cases (14/17, in which 47/55 expanders were implanted, and giant nevus in 3/17 cases in which 8/55 expanders were implanted. Extrusion of the expander occurred in 8/55 expanders (14.5%, which occurred in 6/14 patients. The highest percentage of extrusion occurred in the neck in which two out of three expanders extruded; otherwise this complication does not seem to be related to the indication, gender, nor age of the patients. It seems to be that it is technical in nature. The patients did not have to get any injections to fill the tissue expanders, which made the expansion process less painful and more convenient. Conclusion. This seems to be currently the largest published review in which second generation expanders were used

  18. Tissue expander infections in children: look beyond the expander pocket.

    Science.gov (United States)

    Mason, A C; Davison, S P; Manders, E K

    1999-11-01

    Infection of the expander pocket is the most common complication encountered with soft-tissue expansion. It is usually due to direct inoculation with skin flora either at the time of expander insertion or from extrusion of the device. The authors report two cases of infection of tissue expanders in which the children had concomitant infected sites distant from the prosthesis. Etiological bacteria of common pediatric infections like otitis media and pharyngitis were cultured from the infected expander pocket, raising suspicion that translocation of the organism to the expander had occurred. Aggressive antibiotic treatment, removal of the prosthesis, and flap advancement is advocated.

  19. Low-order models of a single-screw expander for organic Rankine cycle applications

    Science.gov (United States)

    Ziviani, D.; Desideri, A.; Lemort, V.; De Paepe, M.; van den Broek, M.

    2015-08-01

    Screw-type volumetric expanders have been demonstrated to be a suitable technology for organic Rankine cycle (ORC) systems because of higher overall effectiveness and good part-load behaviour over other positive displacement machines. An 11 kWe single-screw expander (SSE) adapted from an air compressor has been tested in an ORC test-rig operating with R245fa as working fluid. A total of 60 steady-steady points have been obtained at four different rotational speeds of the expander in the range between 2000 rpm and 3300 rpm. The maximum electrical power output and overall isentropic effectiveness measured were 7.3 kW and 51.9%, respectively. In this paper, a comparison between two low-order models is proposed in terms of accuracy of the predictions, the robustness of the model and the computational time. The first model is the Pacejka equation-based model and the second is a semi-empirical model derived from a well-known scroll expander model and modified to include the geometric aspects of a single screw expander. The models have been calibrated with the available steady-state measurement points by identifying the proper parameters.

  20. Covered Balloon-Expanding Stents in Airway Stenosis.

    Science.gov (United States)

    Majid, Adnan; Kheir, Fayez; Chung, Jey; Alape, Daniel; Husta, Bryan; Oh, Scott; Folch, Erik

    2017-04-01

    The balloon-expanding stents are widely available but rarely described for use within the tracheobronchial tree. This report describes our experience with these stents in airway stenosis particularly as a lobar salvage therapy. This was a retrospective review of all records in which the balloon-expanding stents were used at a tertiary medical center. Ages, sex, location of stenosis, etiology of stenosis, stent size, duration of stent placement and associated interventions for airway stenosis were recorded. Patient's self-reported respiratory symptoms, dyspnea scale, and radiographic imaging at baseline and after stent placement were also reported. Twenty-one Atrium iCAST stents were inserted in 18 patients with malignant and benign airway disease. The median age was 69.5 years (interquartile range, 53.5 to 74). Most stents (n=20, 95%) were deployed in the lobar airways. There was a significant improvement in the modified Medical Research Council dyspnea scale from median of 3 to 2 (Pstent placement was achieved in 15 patients (83%). No deaths were related to airway stenting complications. Adverse events related to stents included migration (n=2, 9.5%), granulation tissue formation (n=2, 9.5%) and mucus plugging (n=1, 4.8%). Lobar stenting with balloon-expanding metallic stents appears feasible, safe and improves symptoms as well as radiographic atelectasis in patients with lobar airway stenosis in this small case series. Larger studies are needed to confirm this observation and to address long-term safety.

  1. Rib cage deformity during two-stage tissue expander breast reconstruction in patient with previous radiotherapy: a case report

    Directory of Open Access Journals (Sweden)

    Aleš Porčnik

    2016-02-01

    Full Text Available Patients undergoing two-stage breast reconstruction with tissue expander and a history of previous irradiation are predisposed to a various chest-wall deformations more than non-irradiated patients. If chest-wall depression with/without rib fracture is found intra-operatively, bigger implant should be used, with a subsequent radiologic evaluation. In the future, the development of a new, modified expander with a harder base could minimise such complications.

  2. The resistance to PWSCC of explosively expanded Alloy 600 tube-to-tubesheet joints

    International Nuclear Information System (INIS)

    Gold, R.E.; Pement, F.W.; Tarabek, S.A.; Economy, G.

    1992-01-01

    Experimental evaluations were performed to determine the approximate magnitude of the residual stresses associated with explosively expanded steam generator tubing, and to assess the resistance to primary water stress corrosion cracking (PWSCC) of these expansions. Indexing of residual stresses was performed by means of magnesium chloride exposures of surrogate stainless steel mockups. The PWSCC resistance was evaluated by the testing of pressurized mockups of explosively expanded mill annealed Alloy 600 tubing in a highly accelerated Alloy 600 tubing in a highly accelerated steam test environment. Shot peening of the inside tube surfaces was demonstrated to be effective in modifying the residual stresses, providing additional resistance to PWSCC

  3. Generalizing the bms3 and 2D-conformal algebras by expanding the Virasoro algebra

    Science.gov (United States)

    Caroca, Ricardo; Concha, Patrick; Rodríguez, Evelyn; Salgado-Rebolledo, Patricio

    2018-03-01

    By means of the Lie algebra expansion method, the centrally extended conformal algebra in two dimensions and the bms3 algebra are obtained from the Virasoro algebra. We extend this result to construct new families of expanded Virasoro algebras that turn out to be infinite-dimensional lifts of the so-called Bk, Ck and Dk algebras recently introduced in the literature in the context of (super)gravity. We also show how some of these new infinite-dimensional symmetries can be obtained from expanded Kač-Moody algebras using modified Sugawara constructions. Applications in the context of three-dimensional gravity are briefly discussed.

  4. Deployment and testing of a second prototype expandable surgical chamber in microgravity

    Science.gov (United States)

    Markham, Sanford M.; Rock, John A.

    1991-01-01

    During microgravity exposure, two separate expandable surgical chambers were tested. Both chambers had been modified to fit the microgravity work station without extending over the sides of the table. Both chambers were attached to a portable laminar flow generator which served two purposes: to keep the chambers expanded during use; and to provide an operative area environment free of contamination. During the tests, the chambers were placed on various parts of a total body moulage to simulate management of several types of trauma. The tests consisted of cleansing contusions, debridement of burns, and suturing of lacerations. Also, indigo carmine dye was deliberately injected into the chamber during the tests to determine the ease of cleansing the chamber walls after contamination by escaping fluids. Upon completion of the tests, the expandable surgical chambers were deflated, folded, and placed in a flattened state back into their original containers for storage and later disposal. Results are briefly discussed.

  5. Evaluated Rayleigh integrals for pulsed planar expanding ring sources

    International Nuclear Information System (INIS)

    Warshaw, S.I.

    1985-01-01

    Time-domain analytic and semianalytic pressure fields acoustically radiated from expanding pulsed ring sources imbedded in a planar rigid baffle have been calculated. The source functions are radially symmetric delta-function distributions whose amplitude and argument have simple functional dependencies on radius and time. Certain cases yield closed analytic results, while others result in elliptic integrals, which are evaluated to high accuracy by Gauss-Chebyshev and modified Gauss-Legendre quadrature. These results are of value for calibrating computer simulations and convolution procedures, and estimating fields from more complex planar radiators. 3 refs., 4 figs

  6. What Expands in an Expanding Universe?

    Science.gov (United States)

    Pacheco, José A De Freitas

    2015-01-01

    In the present investigation, the possible effects of the expansion of the Universe on systems bonded either by gravitational or electromagnetic forces, are reconsidered. It will be shown that the acceleration (positive or negative) of the expanding background, is the determinant factor affecting planetary orbits and atomic sizes. In the presently accepted cosmology (ΛCDM) all bonded systems are expanding at a decreasing rate that tends to be zero as the universe enters in a de Sitter phase. It is worth mentioning that the estimated expansion rates are rather small and they can be neglected for all practical purposes.

  7. What Expands in an Expanding Universe?

    Directory of Open Access Journals (Sweden)

    JOSÉ A. DE FREITAS PACHECO

    2015-12-01

    Full Text Available ABSTRACT In the present investigation, the possible effects of the expansion of the Universe on systems bonded either by gravitational or electromagnetic forces, are reconsidered. It will be shown that the acceleration (positive or negative of the expanding background, is the determinant factor affecting planetary orbits and atomic sizes. In the presently accepted cosmology (ΛCDM all bonded systems are expanding at a decreasing rate that tends to be zero as the universe enters in a de Sitter phase. It is worth mentioning that the estimated expansion rates are rather small and they can be neglected for all practical purposes.

  8. A modifier of Huntington's disease onset at the MLH1 locus.

    Science.gov (United States)

    Lee, Jong-Min; Chao, Michael J; Harold, Denise; Abu Elneel, Kawther; Gillis, Tammy; Holmans, Peter; Jones, Lesley; Orth, Michael; Myers, Richard H; Kwak, Seung; Wheeler, Vanessa C; MacDonald, Marcy E; Gusella, James F

    2017-10-01

    Huntington's disease (HD) is a dominantly inherited neurodegenerative disease caused by an expanded CAG repeat in HTT. Many clinical characteristics of HD such as age at motor onset are determined largely by the size of HTT CAG repeat. However, emerging evidence strongly supports a role for other genetic factors in modifying the disease pathogenesis driven by mutant huntingtin. A recent genome-wide association analysis to discover genetic modifiers of HD onset age provided initial evidence for modifier loci on chromosomes 8 and 15 and suggestive evidence for a locus on chromosome 3. Here, genotyping of candidate single nucleotide polymorphisms in a cohort of 3,314 additional HD subjects yields independent confirmation of the former two loci and moves the third to genome-wide significance at MLH1, a locus whose mouse orthologue modifies CAG length-dependent phenotypes in a Htt-knock-in mouse model of HD. Both quantitative and dichotomous association analyses implicate a functional variant on ∼32% of chromosomes with the beneficial modifier effect that delays HD motor onset by 0.7 years/allele. Genomic DNA capture and sequencing of a modifier haplotype localize the functional variation to a 78 kb region spanning the 3'end of MLH1 and the 5'end of the neighboring LRRFIP2, and marked by an isoleucine-valine missense variant in MLH1. Analysis of expression Quantitative Trait Loci (eQTLs) provides modest support for altered regulation of MLH1 and LRRFIP2, raising the possibility that the modifier affects regulation of both genes. Finally, polygenic modification score and heritability analyses suggest the existence of additional genetic modifiers, supporting expanded, comprehensive genetic analysis of larger HD datasets. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Experimental study with gianturco stent in the trachea of rabbit

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeong Kook; Kim, Yun Hwan; Suh, Won Hyuck [College of Medicine, Korea University, Seoul (Korea, Republic of)

    1991-09-15

    An expendable stainless steel stent was formulated for use in treatment of tracheobronchial stenosis, tracheomalacia and air way collapse following tracheal reconstruction. The stents were placed throughout an endobronchial tube into the trachea of 20 healthy rabbits. Two different of sizes (10mm, A type and 20mm, B type in diameter and length) and two kinds of shapes (standard, A and B and modified, A' and B' with barbs) were used. Group I were used with A and A' type stents and group II were used with B and B' types. The animals were observed under fluoroscopy and findings were later confirmed at autopsy. With the exception of 2 cases where the stents migrated. 1 case in A subgroup and A' and an inflammatory reaction was noted in each animal. Group II rabbits were almost died within 2-4 weeks after stent placement. In the comparison of the pathohistologic findings between group I and II, the tissue necrosis at the sites of stent placement in trachea is more severe and extensive in group II than that of group I, and also reactive fibroblastic reaction is more severe in group II. So the thickness of the tracheal wall in group II is two or three times thicker than that of group I which seems to be a result of reactive fibrosis. So, A and A' type stent is safer than B and B' type stent in normal rabbit trachea. It is advisable to use stents in diameter under 2 times to tracheal width and the complication of stent placement in trachea may be reduced for appropriate reconstruction of stenotic lesion.

  10. Experimental study with gianturco stent in the trachea of rabbit

    International Nuclear Information System (INIS)

    Park, Jeong Kook; Kim, Yun Hwan; Suh, Won Hyuck

    1991-01-01

    An expendable stainless steel stent was formulated for use in treatment of tracheobronchial stenosis, tracheomalacia and air way collapse following tracheal reconstruction. The stents were placed throughout an endobronchial tube into the trachea of 20 healthy rabbits. Two different of sizes (10mm, A type and 20mm, B type in diameter and length) and two kinds of shapes (standard, A and B and modified, A' and B' with barbs) were used. Group I were used with A and A' type stents and group II were used with B and B' types. The animals were observed under fluoroscopy and findings were later confirmed at autopsy. With the exception of 2 cases where the stents migrated. 1 case in A subgroup and A' and an inflammatory reaction was noted in each animal. Group II rabbits were almost died within 2-4 weeks after stent placement. In the comparison of the pathohistologic findings between group I and II, the tissue necrosis at the sites of stent placement in trachea is more severe and extensive in group II than that of group I, and also reactive fibroblastic reaction is more severe in group II. So the thickness of the tracheal wall in group II is two or three times thicker than that of group I which seems to be a result of reactive fibrosis. So, A and A' type stent is safer than B and B' type stent in normal rabbit trachea. It is advisable to use stents in diameter under 2 times to tracheal width and the complication of stent placement in trachea may be reduced for appropriate reconstruction of stenotic lesion

  11. Experimental study with gianturco stent in the trachea of rabbit

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeong Kook; Kim, Yun Hwan; Suh, Won Hyuck [College of Medicine, Korea University, Seoul (Korea, Republic of)

    1991-09-15

    An expendable stainless steel stent was formulated for use in treatment of tracheobronchial stenosis, tracheomalacia and air way collapse following tracheal reconstruction. The stents were placed throughout an endobronchial tube into the trachea of 20 healthy rabbits. Two different of sizes (10mm, A type and 20mm, B type in diameter and length) and two kinds of shapes (standard, A and B and modified, A' and B' with barbs) were used. Group I were used with A and A' type stents and group II were used with B and B' types. The animals were observed under fluoroscopy and findings were later confirmed at autopsy. With the exception of 2 cases where the stents migrated. 1 case in A subgroup and A' and an inflammatory reaction was noted in each animal. Group II rabbits were almost died within 2-4 weeks after stent placement. In the comparison of the pathohistologic findings between group I and II, the tissue necrosis at the sites of stent placement in trachea is more severe and extensive in group II than that of group I, and also reactive fibroblastic reaction is more severe in group II. So the thickness of the tracheal wall in group II is two or three times thicker than that of group I which seems to be a result of reactive fibrosis. So, A and A' type stent is safer than B and B' type stent in normal rabbit trachea. It is advisable to use stents in diameter under 2 times to tracheal width and the complication of stent placement in trachea may be reduced for appropriate reconstruction of stenotic lesion.

  12. Expanding subjectivities

    DEFF Research Database (Denmark)

    Lundgaard Andersen, Linda; Soldz, Stephen

    2012-01-01

    A major theme in recent psychoanalytic thinking concerns the use of therapist subjectivity, especially “countertransference,” in understanding patients. This thinking converges with and expands developments in qualitative research regarding the use of researcher subjectivity as a tool......-Saxon and continental traditions, this special issue provides examples of the use of researcher subjectivity, informed by psychoanalytic thinking, in expanding research understanding....

  13. The expanding universe of p53 targets.

    Science.gov (United States)

    Menendez, Daniel; Inga, Alberto; Resnick, Michael A

    2009-10-01

    The p53 tumour suppressor is modified through mutation or changes in expression in most cancers, leading to the altered regulation of hundreds of genes that are directly influenced by this sequence-specific transcription factor. Central to the p53 master regulatory network are the target response element (RE) sequences. The extent of p53 transactivation and transcriptional repression is influenced by many factors, including p53 levels, cofactors and the specific RE sequences, all of which contribute to the role that p53 has in the aetiology of cancer. This Review describes the identification and functionality of REs and highlights the inclusion of non-canonical REs that expand the universe of genes and regulation mechanisms in the p53 tumour suppressor network.

  14. Consumers’ acceptance and preferences for nutrition-modified and functional dairy products

    NARCIS (Netherlands)

    Bimbo, Francesco; Bonanno, Alessandro; Nocella, Giuseppe; Viscecchia, Rosaria; Nardone, Gianluca; Devitiis, De Biagia; Carlucci, Domenico

    2017-01-01

    This systematic literature review collects and summarizes research on consumer acceptance and preferences for nutrition-modified and functional dairy products, to reconcile, and expand upon, the findings of previous studies. We find that female consumers show high acceptance for some functional

  15. Steric restrictions of RISC in RNA interference identified with size-expanded RNA nucleobases.

    Science.gov (United States)

    Hernández, Armando R; Peterson, Larryn W; Kool, Eric T

    2012-08-17

    Understanding the interactions between small interfering RNAs (siRNAs) and the RNA-induced silencing complex (RISC), the key protein complex of RNA interference (RNAi), is of great importance to the development of siRNAs with improved biological and potentially therapeutic function. Although various chemically modified siRNAs have been reported, relatively few studies with modified nucleobases exist. Here we describe the synthesis and hybridization properties of siRNAs bearing size-expanded RNA (xRNA) nucleobases and their use as a novel and systematic set of steric probes in RNAi. xRNA nucleobases are expanded by 2.4 Å using benzo-homologation and retain canonical Watson-Crick base-pairing groups. Our data show that the modified siRNA duplexes display small changes in melting temperature (+1.4 to -5.0 °C); substitutions near the center are somewhat destabilizing to the RNA duplex, while substitutions near the ends are stabilizing. RNAi studies in a dual-reporter luciferase assay in HeLa cells revealed that xRNA nucleobases in the antisense strand reduce activity at some central positions near the seed region but are generally well tolerated near the ends. Most importantly, we observed that xRNA substitutions near the 3'-end increased activity over that of wild-type siRNAs. The data are analyzed in terms of site-dependent steric effects in RISC. Circular dichroism experiments show that single xRNA substitutions do not significantly distort the native A-form helical structure of the siRNA duplex, and serum stability studies demonstrated that xRNA substitutions protect siRNAs against nuclease degradation.

  16. Dental extrusion with orthodontic miniscrew anchorage: a case report describing a modified method.

    Science.gov (United States)

    Horliana, Ricardo Fidos; Horliana, Anna Carolina Ratto Tempestini; Wuo, Alexandre do Vale; Perez, Flávio Eduardo Guillin; Abrão, Jorge

    2015-01-01

    In recent years, the skeletal anchorage through miniscrews has expanded the treatment options in orthodontics (Yamaguchi et al., 2012). We hereby present a modified method for tooth extrusion for cases where crown-lengthening surgery is contraindicated for aesthetic reasons. This modified method uses three orthodontic appliances: a mini-implant, an orthodontic wire, and a bracket. The aim of this case report was to increase the length of the clinical crown of a fractured tooth (tooth 23) by means of an orthodontic extrusion with the modified method of Roth and Diedrich.

  17. Expanding Thurston maps

    CERN Document Server

    Bonk, Mario

    2017-01-01

    This monograph is devoted to the study of the dynamics of expanding Thurston maps under iteration. A Thurston map is a branched covering map on a two-dimensional topological sphere such that each critical point of the map has a finite orbit under iteration. It is called expanding if, roughly speaking, preimages of a fine open cover of the underlying sphere under iterates of the map become finer and finer as the order of the iterate increases. Every expanding Thurston map gives rise to a fractal space, called its visual sphere. Many dynamical properties of the map are encoded in the geometry of this visual sphere. For example, an expanding Thurston map is topologically conjugate to a rational map if and only if its visual sphere is quasisymmetrically equivalent to the Riemann sphere. This relation between dynamics and fractal geometry is the main focus for the investigations in this work.

  18. SRS K-area material storage. Expanding capabilities

    International Nuclear Information System (INIS)

    Koenig, R.

    2013-01-01

    In support of the Department of Energy’s continued plans to de-inventory and reduce the footprint of Cold War era weapons’ material production sites, the K-Area Material Storage (KAMS) facility, located in the K-Area Complex (KAC) at the Savannah River Site reservation, has expanded since its startup authorization in 2000 to accommodate DOE’s material consolidation mission. During the facility’s growth and expansion, KAMS will have expanded its authorization capability of material types and storage containers to allow up to 8200 total shipping containers once the current expansion effort completes in 2014. Recognizing the need to safely and cost effectively manage other surplus material across the DOE Complex, KAC is constantly evaluating the storage of different material types within K area. When modifying storage areas in KAC, the Documented Safety Analysis (DSA) must undergo extensive calculations and reviews; however, without an extensive and proven security posture the possibility for expansion would not be possible. The KAC maintains the strictest adherence to safety and security requirements for all the SNM it handles. Disciplined Conduct of Operations and Conduct of Projects are demonstrated throughout this historical overview highlighting various improvements in capability, capacity, demonstrated cost effectiveness and utilization of the KAC as the DOE Center of Excellence for safe and secure storage of surplus SNM.

  19. Genetically Modified Organisms

    Directory of Open Access Journals (Sweden)

    Claro Llaguno

    2001-06-01

    Full Text Available Recent reports have brought to public attention concerns about Bt corn and genetically modified organisms (GMO in general. The timing, it seems, is most appropriate considering two related developments early this year: the final approval of the Cartagena Protocol on Biosafety in Montreal on January 29, 2001, and the OECD Edinburgh Conference on GM food safety last February 28- March 1, 2001. The protocol makes clear that GMOs include all living modified organisms (LMO defined as "any living organism that possesses a novel combination of genetic material obtained through the use of modern biotechnology". This includes seeds, live fish, and other organisms intentionally obtained for release to the environment. It would seem that the common understanding about GMOs as referring to farm-to-table products is perforce expanded to embrace genetically modified farm animals and aquatic resources. Being a trade agreement, the Montreal accord primarily deals with the safety issues related to the transboundary movement of LMOs around the globe. The OECD conference on the other hand, called for an international body "to address all sides of the GM debate" in response to the public outcry, particularly in Western Europe, regarding the risks the new products pose to human health and the environment. Some points of contention, which remain unresolved, include issues such as whether countries should be allowed to develop their own GM food based on their needs, and whether a global moratorium on GMOs and mandatory labeling should be enforced worldwide.

  20. Deleterious mutations can surf to high densities on the wave front of an expanding population.

    Science.gov (United States)

    Travis, Justin M J; Münkemüller, Tamara; Burton, Olivia J; Best, Alex; Dytham, Calvin; Johst, Karin

    2007-10-01

    There is an increasing recognition that evolutionary processes play a key role in determining the dynamics of range expansion. Recent work demonstrates that neutral mutations arising near the edge of a range expansion sometimes surf on the expanding front leading them rather than that leads to reach much greater spatial distribution and frequency than expected in stationary populations. Here, we extend this work and examine the surfing behavior of nonneutral mutations. Using an individual-based coupled-map lattice model, we confirm that, regardless of its fitness effects, the probability of survival of a new mutation depends strongly upon where it arises in relation to the expanding wave front. We demonstrate that the surfing effect can lead to deleterious mutations reaching high densities at an expanding front, even when they have substantial negative effects on fitness. Additionally, we highlight that this surfing phenomenon can occur for mutations that impact reproductive rate (i.e., number of offspring produced) as well as mutations that modify juvenile competitive ability. We suggest that these effects are likely to have important consequences for rates of spread and the evolution of spatially expanding populations.

  1. A comparative investigation on absorption performances of three expanded graphite-based complex materials for toluene

    International Nuclear Information System (INIS)

    Li Shande; Tian Shuanghong; Feng Yunfeng; Lei Jiajia; Wang, Piaopiao; Xiong Ya

    2010-01-01

    Three kinds of expanded graphite-based complex materials were prepared to absorb toluene by dispersing plant oil, animal oil and mineral oil on the surface of expanded graphite, respectively. These complex materials were characterized by scanning electronic micrograph, contact angle meter and Brunauer-Emmett-Teller surface area. And their absorption capacities for toluene were comparatively investigated. The results showed that the surfaces of the three types of sorbents were very hydrophobic and nonporous, but they all had excellent absorption capacities for toluene. And their absorption capacities were proportional to the toluene concentration in streams and decreased differently with increasing the absorption temperature. It was noteworthy that the absorption capacities varied with the unsaturated degree of the complex materials and kept unchanged under different relative humidities of streams. Moreover, the regeneration experiments showed that after 15-run regeneration the absorption capacities of expanded graphite modified by mineral oil almost kept unchanged, while that of expanded graphite loaded plant oil and animal oil dropped by 157 and 93.6 mg g -1 , respectively. The losses of their absorption capacities were ascribed to the destruction of their unsaturated carbon bounds.

  2. Comparison of self-expandable and balloon-expanding stents for hybrid ductal stenting in hypoplastic left heart complex.

    Science.gov (United States)

    Goreczny, Sebastian; Qureshi, Shakeel A; Rosenthal, Eric; Krasemann, Thomas; Nassar, Mohamed S; Anderson, David R; Morgan, Gareth J

    2017-07-01

    We aimed to compare the procedural and mid-term performance of a specifically designed self-expanding stent with balloon-expandable stents in patients undergoing hybrid palliation for hypoplastic left heart syndrome and its variants. The lack of specifically designed stents has led to off-label use of coronary, biliary, or peripheral stents in the neonatal ductus arteriosus. Recently, a self-expanding stent, specifically designed for use in hypoplastic left heart syndrome, has become available. We carried out a retrospective cohort comparison of 69 neonates who underwent hybrid ductal stenting with balloon-expandable and self-expanding stents from December, 2005 to July, 2014. In total, 43 balloon-expandable stents were implanted in 41 neonates and more recently 47 self-expanding stents in 28 neonates. In the balloon-expandable stents group, stent-related complications occurred in nine patients (22%), compared with one patient in the self-expanding stent group (4%). During follow-up, percutaneous re-intervention related to the ductal stent was performed in five patients (17%) in the balloon-expandable stent group and seven patients (28%) in self-expanding stents group. Hybrid ductal stenting with self-expanding stents produced favourable results when compared with the results obtained with balloon-expandable stents. Immediate additional interventions and follow-up re-interventions were similar in both groups with complications more common in those with balloon-expandable stents.

  3. Beam aperture modifier design with acoustic metasurfaces

    Science.gov (United States)

    Tang, Weipeng; Ren, Chunyu

    2017-10-01

    In this paper, we present a design concept of acoustic beam aperture modifier using two metasurface-based planar lenses. By appropriately designing the phase gradient profile along the metasurface, we obtain a class of acoustic convex lenses and concave lenses, which can focus the incoming plane waves and collimate the converging waves, respectively. On the basis of the high converging and diverging capability of these lenses, two kinds of lens combination scheme, including the convex-concave type and convex-convex type, are proposed to tune up the incoming beam aperture as needed. To be specific, the aperture of the acoustic beam can be shrunk or expanded through adjusting the phase gradient of the pair of lenses and the spacing between them. These lenses and the corresponding aperture modifiers are constructed by the stacking ultrathin labyrinthine structures, which are obtained by the geometry optimization procedure and exhibit high transmission coefficient and a full range of phase shift. The simulation results demonstrate the effectiveness of our proposed beam aperture modifiers. Due to the flexibility in aperture controlling and the simplicity in fabrication, the proposed modifiers have promising potential in applications, such as acoustic imaging, nondestructive evaluation, and communication.

  4. Two Types of Expanding Lie Algebra and New Expanding Integrable Systems

    International Nuclear Information System (INIS)

    Dong Huanhe; Yang Jiming; Wang Hui

    2010-01-01

    From a new Lie algebra proposed by Zhang, two expanding Lie algebras and its corresponding loop algebras are obtained. Two expanding integrable systems are produced with the help of the generalized zero curvature equation. One of them has complex Hamiltion structure with the help of generalized Tu formula (GTM). (general)

  5. Dental Extrusion with Orthodontic Miniscrew Anchorage: A Case Report Describing a Modified Method

    OpenAIRE

    Horliana, Ricardo Fidos; Horliana, Anna Carolina Ratto Tempestini; Wuo, Alexandre do Vale; Perez, Fl?vio Eduardo Guillin; Abr?o, Jorge

    2015-01-01

    In recent years, the skeletal anchorage through miniscrews has expanded the treatment options in orthodontics (Yamaguchi et al., 2012). We hereby present a modified method for tooth extrusion for cases where crown-lengthening surgery is contraindicated for aesthetic reasons. This modified method uses three orthodontic appliances: a mini-implant, an orthodontic wire, and a bracket. The aim of this case report was to increase the length of the clinical crown of a fractured tooth (tooth 23) by m...

  6. Expanding plasma jet in a vacuum vessel

    International Nuclear Information System (INIS)

    Chutov, Yu.I.; Kravchenko, A.Yu.; Yakovetskij, V.S.

    1998-01-01

    The paper deals with numerical calculations of parameters of a supersonic quasi-neutral argon plasma jet expanding into a cylindrical vacuum vessel and interacting with its inner surface. A modified method of large particles was used, the complex set of hydrodynamic equations being broken into simpler components, each of which describes a separate physical process. Spatial distributions of the main parameters of the argon plasma jet were simulated at various times after the jet entering the vacuum vessel, the parameters being the jet velocity field, the full plasma pressure, the electron temperature, the temperature of heavy particles, and the degree of ionization. The results show a significant effect of plasma jet interaction on the plasma parameters. The jet interaction with the vessel walls may result e.g. in excitation of shock waves and rotational plasma motions. (J.U.)

  7. Expander for Thin-Wall Tubing

    Science.gov (United States)

    Pessin, R.

    1983-01-01

    Tool locally expands small-diameter tubes. Tube expander locally expands and deforms tube: Compressive lateral stress induced in elastomeric sleeve by squeezing axially between two metal tool parts. Adaptable to situations in which tube must have small bulge for mechanical support or flow control.

  8. In Vitro Comparison of Self-Expanding Versus Balloon-Expandable Stents in a Human Ex Vivo Model

    International Nuclear Information System (INIS)

    Grenacher, Lars; Rohde, Stefan; Gaenger, Ellen; Deutsch, Jochen; Kauffmann, Guenter W.; Richter, Goetz M.

    2006-01-01

    The objective was to compare the radial strength and expansile precision of self-expanding stents and balloon-expandable stents in a human cadaver bifurcation model. Seven different self-expanding (LUMINEXX, JOSTENT SelfX, JOSTENT SelfX hrf, Sinus-Repo, Sinus SuperFlex, Easy Wallstent, SMART) and four different balloon-expandable stent models (Palmaz, Sinus Stent, SAXX Medium, JOSTENT peripheral), each type 10 stents (total n = 110 stents) were implanted into the common iliac arteries of human cadaver corpses. The maximum stent diameter was 10 mm for all models. After stent implantation, the specimens were filled with silicone caoutchouc. After 24 h, the vascular walls including the stents were removed from the hardened casts. Diameters were taken and the weight of the cast cylinders was measured in air and in purified water to calculate the volume of the bodies (according to Archimedes Law) as a relative but precise degree for the radial strength of the implanted stents. The cylindrical casts of the self-expanding stents showed lower mean diameters (8.2 ± 1.0 mm) and mean volumes (0.60 ± 0.14 ml/cm) than in the balloon-expandable stent group (10.1 ± 0.3 mm and 0.71 ± 0.04 ml/cm, respectively; p < 0.01). The nominal maximum diameter of 10 mm was not achieved in any of the self-expanding stents, but this was achieved in more than 70% (29/40) of the balloon-expandable stent specimens (p < 0.05). The variation between achieved volumes was significantly larger in self-expanding (range: 0.23-0.78 ml/cm) than in balloon-expandable stents (range: 0.66-0.81 ml/cm; p < 0.05). Self-expanding stents presented considerably lower radial expansion force and lower degree of precision than balloon-expandable stents

  9. Reduction of residual stresses in internal skin of transient zones of PWR steam generator expanded tubes: tests with a ''rotating brush''

    International Nuclear Information System (INIS)

    Vidal, P.

    1984-04-01

    A process aiming at preventing or suppressing cracks under stress corrosion on the primary side in the expanded zones of PWR steam generator tubes has been studied; it consists in hammering the internal skin of tubes in these zones what reduces the level of residual expanding stresses to lower values around 100-150 MPa without modifying the stress level in external skin. Tests in magnesium chloride to estimate the residual stresses of tubes in low carbon stainless austenitic steel 18% Cr-12% Ni with molybdene [fr

  10. Spatiotemporal patterns of non-genetically modified crops in the era of expansion of genetically modified food.

    Science.gov (United States)

    Sun, Jing; Wu, Wenbin; Tang, Huajun; Liu, Jianguo

    2015-09-18

    Despite heated debates over the safety of genetically modified (GM) food, GM crops have been expanding rapidly. Much research has focused on the expansion of GM crops. However, the spatiotemporal dynamics of non-genetically modified (non-GM) crops are not clear, although they may have significant environmental and agronomic impacts and important policy implications. To understand the dynamics of non-GM crops and to inform the debates among relevant stakeholders, we conducted spatiotemporal analyses of China's major non-GM soybean production region, the Heilongjiang Province. Even though the total soybean planting area decreased from 2005 to 2010, surprisingly, there were hotspots of increase. The results also showed hotspots of loss as well as a large decline in the number and continuity of soybean plots. Since China is the largest non-GM soybean producer in the world, the decline of its major production region may signal the continual decline of global non-GM soybeans.

  11. Microbial Biofilms and Breast Tissue Expanders

    Directory of Open Access Journals (Sweden)

    Melissa J. Karau

    2013-01-01

    Full Text Available We previously developed and validated a vortexing-sonication technique for detection of biofilm bacteria on the surface of explanted prosthetic joints. Herein, we evaluated this technique for diagnosis of infected breast tissue expanders and used it to assess colonization of breast tissue expanders. From April 2008 to December 2011, we studied 328 breast tissue expanders at Mayo Clinic, Rochester, MN, USA. Of seven clinically infected breast tissue expanders, six (85.7% had positive cultures, one of which grew Propionibacterium species. Fifty-two of 321 breast tissue expanders (16.2%, 95% CI, 12.3–20.7% without clinical evidence of infection also had positive cultures, 45 growing Propionibacterium species and ten coagulase-negative staphylococci. While vortexing-sonication can detect clinically infected breast tissue expanders, 16 percent of breast tissue expanders appear to be asymptomatically colonized with normal skin flora, most commonly, Propionibacterium species.

  12. Silicon microfabricated beam expander

    Science.gov (United States)

    Othman, A.; Ibrahim, M. N.; Hamzah, I. H.; Sulaiman, A. A.; Ain, M. F.

    2015-03-01

    The feasibility design and development methods of silicon microfabricated beam expander are described. Silicon bulk micromachining fabrication technology is used in producing features of the structure. A high-precision complex 3-D shape of the expander can be formed by exploiting the predictable anisotropic wet etching characteristics of single-crystal silicon in aqueous Potassium-Hydroxide (KOH) solution. The beam-expander consist of two elements, a micromachined silicon reflector chamber and micro-Fresnel zone plate. The micro-Fresnel element is patterned using lithographic methods. The reflector chamber element has a depth of 40 µm, a diameter of 15 mm and gold-coated surfaces. The impact on the depth, diameter of the chamber and absorption for improved performance are discussed.

  13. Bigelow Expandable Activity Module Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Bigelow Expandable Activity Module (BEAM) project is a NASA-industry partnership with Bigelow Aerospace (BA) that has developing the first human-rated expandable...

  14. Helium turbo-expander with an alternator

    International Nuclear Information System (INIS)

    Akiyama, Yoshitane

    1980-01-01

    Study was made on a helium turbo-expander, the heart of helium refrigerator systems, in order to develop a system which satisfies the required conditions. A helium turbo-expander with externally pressurized helium gas bearings at the temperature of liquid nitrogen and an alternator as a brake have been employed. The essential difference between a helium turbo-expander and a nitrogen turbo-expander was clarified. The gas bearing lubricated with nitrogen at room temperature and the gas bearing lubricated with helium at low temperature were tested. The flow rate of helium in a helium refrigerator for a large superconducting magnet is comparatively small, therefore a helium turbine must be small, but the standard for large turbine design can be applied to such small turbine. Using the alternator as a brake, the turbo-expander was easily controllable electrically. The prototype turbo-expander was made, and the liquefaction test with it and MHD power generation test were carried out. (Kako, I.)

  15. Silicon microfabricated beam expander

    International Nuclear Information System (INIS)

    Othman, A.; Ibrahim, M. N.; Hamzah, I. H.; Sulaiman, A. A.; Ain, M. F.

    2015-01-01

    The feasibility design and development methods of silicon microfabricated beam expander are described. Silicon bulk micromachining fabrication technology is used in producing features of the structure. A high-precision complex 3-D shape of the expander can be formed by exploiting the predictable anisotropic wet etching characteristics of single-crystal silicon in aqueous Potassium-Hydroxide (KOH) solution. The beam-expander consist of two elements, a micromachined silicon reflector chamber and micro-Fresnel zone plate. The micro-Fresnel element is patterned using lithographic methods. The reflector chamber element has a depth of 40 µm, a diameter of 15 mm and gold-coated surfaces. The impact on the depth, diameter of the chamber and absorption for improved performance are discussed

  16. Silicon microfabricated beam expander

    Energy Technology Data Exchange (ETDEWEB)

    Othman, A., E-mail: aliman@ppinang.uitm.edu.my; Ibrahim, M. N.; Hamzah, I. H.; Sulaiman, A. A. [Faculty of Electrical Engineering, Universiti Teknologi MARA Malaysia, 40450, Shah Alam, Selangor (Malaysia); Ain, M. F. [School of Electrical and Electronic Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, 14300,Nibong Tebal, Pulau Pinang (Malaysia)

    2015-03-30

    The feasibility design and development methods of silicon microfabricated beam expander are described. Silicon bulk micromachining fabrication technology is used in producing features of the structure. A high-precision complex 3-D shape of the expander can be formed by exploiting the predictable anisotropic wet etching characteristics of single-crystal silicon in aqueous Potassium-Hydroxide (KOH) solution. The beam-expander consist of two elements, a micromachined silicon reflector chamber and micro-Fresnel zone plate. The micro-Fresnel element is patterned using lithographic methods. The reflector chamber element has a depth of 40 µm, a diameter of 15 mm and gold-coated surfaces. The impact on the depth, diameter of the chamber and absorption for improved performance are discussed.

  17. Modified Block Newton method for the lambda modes problem

    Energy Technology Data Exchange (ETDEWEB)

    González-Pintor, S., E-mail: segonpin@isirym.upv.es [Departamento de Ingeniería Química y Nuclear, Universidad Politécnica de Valencia, Camino de Vera 14, 46022 Valencia (Spain); Ginestar, D., E-mail: dginestar@mat.upv.es [Instituto de Matemática Multidisciplinar, Universidad Politécnica de Valencia, Camino de Vera 14, 46022 Valencia (Spain); Verdú, G., E-mail: gverdu@iqn.upv.es [Departamento de Ingeniería Química y Nuclear, Universidad Politécnica de Valencia, Camino de Vera 14, 46022 Valencia (Spain)

    2013-06-15

    Highlights: ► The Modal Method is based on expanding the solution in a set of dominant modes. ► Updating the set of dominant modes improve its performance. ► A Modified Block Newton Method, which use previous calculated modes, is proposed. ► The method exhibits a very good local convergence with few iterations. ► Good performance results are also obtained for heavy perturbations. -- Abstract: To study the behaviour of nuclear power reactors it is necessary to solve the time dependent neutron diffusion equation using either a rectangular mesh for PWR and BWR reactors or a hexagonal mesh for VVER reactors. This problem can be solved by means of a modal method, which uses a set of dominant modes to expand the neutron flux. For the transient calculations using the modal method with a moderate number of modes, these modes must be updated each time step to maintain the accuracy of the solution. The updating modes process is also interesting to study perturbed configurations of a reactor. A Modified Block Newton method is studied to update the modes. The performance of the Newton method has been tested for a steady state perturbation analysis of two 2D hexagonal reactors, a perturbed configuration of the IAEA PWR 3D reactor and two configurations associated with a boron dilution transient in a BWR reactor.

  18. Expander Codes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 1. Expander Codes - The Sipser–Spielman Construction. Priti Shankar. General Article Volume 10 ... Author Affiliations. Priti Shankar1. Department of Computer Science and Automation, Indian Institute of Science Bangalore 560 012, India.

  19. The expanding universe: an introduction

    OpenAIRE

    Pössel, Markus

    2017-01-01

    An introduction to the physics and mathematics of the expanding universe, using no more than high-school level / undergraduate mathematics. Covered are the basics of scale factor expansion, the dynamics of the expanding universe, various distance concepts and the generalized redshift-luminosity relation, among other topics.

  20. Characterization of surfactant/hydrotalcite-like clay/glassy carbon modified electrodes: Oxidation of phenol

    International Nuclear Information System (INIS)

    Hernandez, Maria; Fernandez, Lenys; Borras, Carlos; Mostany, Jorge; Carrero, Hermes

    2007-01-01

    The characteristics of hydrotalcite (HT)-like clay films containing ionic and nonionic surfactants and their ability to oxidize phenol have been examined. The HT clay (Co/Al-NO 3 ) was synthesized by coprecipitation techniques and then modified with surfactants such as sodium dodecylbenzenesulfonate (SDBS), octylphenoxypolyethoxyethanol (TX100) or cetylpyridinium bromide (CPB). X-ray diffraction analysis revealed that the interlayer basal spacing varied depending on the type of surfactant retained by the HT. The presence of SDBS and CPB expanded the HT interlayer, which in the presence of TX100 did not show an appreciable change. Phenol oxidation is favored at surfactant-HT-GC modified electrodes, after a preconcentration time, compared to phenol oxidation at HT-GC or GC electrodes. Surfactant-HT-GC modified electrodes display good stability in continuous electrochemical phenol oxidation. At pH values between 6 and 10.8, both SDBS-HT-GC and TX100-HT-GC modified electrodes seem to be promising electrodes for the detection of phenol in water; while the CPB-HT-GC modified electrode should be affected by the inorganic anions

  1. Modified echo peak correction for radial acquisition regime (RADAR).

    Science.gov (United States)

    Takizawa, Masahiro; Ito, Taeko; Itagaki, Hiroyuki; Takahashi, Tetsuhiko; Shimizu, Kanichirou; Harada, Junta

    2009-01-01

    Because radial sampling imposes many limitations on magnetic resonance (MR) imaging hardware, such as on the accuracy of the gradient magnetic field or the homogeneity of B(0), some correction of the echo signal is usually needed before image reconstruction. In our previous study, we developed an echo-peak-shift correction (EPSC) algorithm not easily affected by hardware performance. However, some artifacts remained in lung imaging, where tissue is almost absent, or in cardiac imaging, which is affected by blood flow. In this study, we modified the EPSC algorithm to improve the image quality of the radial aquisition regime (RADAR) and expand its application sequences. We assumed the artifacts were mainly caused by errors in the phase map for EPSC and used a phantom on a 1.5-tesla (T) MR scanner to investigate whether to modify the EPSC algorithm. To evaluate the effectiveness of EPSC, we compared results from T(1)- and T(2)-weighted images of a volunteer's lung region using the current and modified EPSC. We then applied the modified EPSC to RADAR spin echo (SE) and RADAR balanced steady-state acquisition with rewound gradient echo (BASG) sequence. The modified EPSC reduced phase discontinuity in the reference data used for EPSC and improved visualization of blood vessels in the lungs. Motion and blood flow caused no visible artifacts in the resulting images in either RADAR SE or RADAR BASG sequence. Use of the modified EPSC eliminated artifacts caused by signal loss in the reference data for EPSC. In addition, the modified EPSC was applied to RADAR SE and RADAR BASG sequences.

  2. Modified echo peak correction for radial acquisition regime (RADAR)

    International Nuclear Information System (INIS)

    Takizawa, Masahiro; Ito, Taeko; Itagaki, Hiroyuki; Takahashi, Tetsuhiko; Shimizu, Kanichirou; Harada, Junta

    2009-01-01

    Because radial sampling imposes many limitations on magnetic resonance (MR) imaging hardware, such as on the accuracy of the gradient magnetic field or the homogeneity of B 0 , some correction of the echo signal is usually needed before image reconstruction. In our previous study, we developed an echo-peak-shift correction (EPSC) algorithm not easily affected by hardware performance. However, some artifacts remained in lung imaging, where tissue is almost absent, or in cardiac imaging, which is affected by blood flow. In this study, we modified the EPSC algorithm to improve the image quality of the radial acquisition regime (RADAR) and expand its application sequences. We assumed the artifacts were mainly caused by errors in the phase map for EPSC and used a phantom on a 1.5-tesla (T) MR scanner to investigate whether to modify the EPSC algorithm. To evaluate the effectiveness of EPSC, we compared results from T 1 -and T 2 -weighted images of a volunteer's lung region using the current and modified EPSC. We then applied the modified EPSC to RADAR spin echo (SE) and RADAR balanced steady-state acquisition with rewound gradient echo (BASG) sequence. The modified EPSC reduced phase discontinuity in the reference data used for EPSC and improved visualization of blood vessels in the lungs. Motion and blood flow caused no visible artifacts in the resulting images in either RADAR SE or RADAR BASG sequence. Use of the modified EPSC eliminated artifacts caused by signal loss in the reference data for EPSC. In addition, the modified EPSC was applied to RADAR SE and RADAR BASG sequences. (author)

  3. A Rapidly Expanding Bose-Einstein Condensate: An Expanding Universe in the Lab

    Science.gov (United States)

    Eckel, S.; Kumar, A.; Jacobson, T.; Spielman, I. B.; Campbell, G. K.

    2018-04-01

    We study the dynamics of a supersonically expanding, ring-shaped Bose-Einstein condensate both experimentally and theoretically. The expansion redshifts long-wavelength excitations, as in an expanding universe. After expansion, energy in the radial mode leads to the production of bulk topological excitations—solitons and vortices—driving the production of a large number of azimuthal phonons and, at late times, causing stochastic persistent currents. These complex nonlinear dynamics, fueled by the energy stored coherently in one mode, are reminiscent of a type of "preheating" that may have taken place at the end of inflation.

  4. Modified Differential Transform Method for Two Singular Boundary Values Problems

    Directory of Open Access Journals (Sweden)

    Yinwei Lin

    2014-01-01

    Full Text Available This paper deals with the two singular boundary values problems of second order. Two singular points are both boundary values points of the differential equation. The numerical solutions are developed by modified differential transform method (DTM for expanded point. Linear and nonlinear models are solved by this method to get more reliable and efficient numerical results. It can also solve ordinary differential equations where the traditional one fails. Besides, we give the convergence of this new method.

  5. Roots Air Management System with Integrated Expander

    Energy Technology Data Exchange (ETDEWEB)

    Stretch, Dale [Eaton Corporation, Menomonee Falls, WI (United States); Wright, Brad [Eaton Corporation, Menomonee Falls, WI (United States); Fortini, Matt [Eaton Corporation, Menomonee Falls, WI (United States); Fink, Neal [Ballard Power Systems, Burnaby, BC (Canada); Ramadan, Bassem [Kettering Univ., Flint, MI (United States); Eybergen, William [Eaton Corporation, Menomonee Falls, WI (United States)

    2016-07-06

    PEM fuel cells remain an emerging technology in the vehicle market with several cost and reliability challenges that must be overcome in order to increase market penetration and acceptance. The DOE has identified the lack of a cost effective, reliable, and efficient air supply system that meets the operational requirements of a pressurized PEM 80kW fuel cell as one of the major technological barriers that must be overcome. This project leveraged Roots positive displacement development advancements and demonstrated an efficient and low cost fuel cell air management system. Eaton built upon its P-Series Roots positive displacement design and shifted the peak efficiency making it ideal for use on an 80kW PEM stack. Advantages to this solution include: • Lower speed of the Roots device eliminates complex air bearings present on other systems. • Broad efficiency map of Roots based systems provides an overall higher drive cycle fuel economy. • Core Roots technology has been developed and validated for other transportation applications. Eaton modified their novel R340 Twin Vortices Series (TVS) Roots-type supercharger for this application. The TVS delivers more power and better fuel economy in a smaller package as compared to other supercharger technologies. By properly matching the helix angle with the rotor’s physical aspect ratio, the supercharger’s peak efficiency can be moved to the operating range where it is most beneficial for the application. The compressor was designed to meet the 90 g/s flow at a pressure ratio of 2.5, similar in design to the P-Series 340. A net shape plastic expander housing with integrated motor and compressor was developed to significantly reduce the cost of the system. This integrated design reduced part count by incorporating an overhung expander and motor rotors into the design such that only four bearings and two shafts were utilized.

  6. A Rapidly Expanding Bose-Einstein Condensate: An Expanding Universe in the Lab

    Directory of Open Access Journals (Sweden)

    S. Eckel

    2018-04-01

    Full Text Available We study the dynamics of a supersonically expanding, ring-shaped Bose-Einstein condensate both experimentally and theoretically. The expansion redshifts long-wavelength excitations, as in an expanding universe. After expansion, energy in the radial mode leads to the production of bulk topological excitations—solitons and vortices—driving the production of a large number of azimuthal phonons and, at late times, causing stochastic persistent currents. These complex nonlinear dynamics, fueled by the energy stored coherently in one mode, are reminiscent of a type of “preheating” that may have taken place at the end of inflation.

  7. Proliferation of Genetically Modified Human Cells on Electrospun Nanofiber Scaffolds

    Directory of Open Access Journals (Sweden)

    Mandula Borjigin

    2012-01-01

    Full Text Available Gene editing is a process by which single base mutations can be corrected, in the context of the chromosome, using single-stranded oligodeoxynucleotides (ssODNs. The survival and proliferation of the corrected cells bearing modified genes, however, are impeded by a phenomenon known as reduced proliferation phenotype (RPP; this is a barrier to practical implementation. To overcome the RPP problem, we utilized nanofiber scaffolds as templates on which modified cells were allowed to recover, grow, and expand after gene editing. Here, we present evidence that some HCT116-19, bearing an integrated, mutated enhanced green fluorescent protein (eGFP gene and corrected by gene editing, proliferate on polylysine or fibronectin-coated polycaprolactone (PCL nanofiber scaffolds. In contrast, no cells from the same reaction protocol plated on both regular dish surfaces and polylysine (or fibronectin-coated dish surfaces proliferate. Therefore, growing genetically modified (edited cells on electrospun nanofiber scaffolds promotes the reversal of the RPP and increases the potential of gene editing as an ex vivo gene therapy application.

  8. The Expanding Universe: Dark Energy

    Energy Technology Data Exchange (ETDEWEB)

    Lincoln, Don [Fermilab; Nord, Brian [Fermilab

    2014-09-01

    In 1998, observations of distant supernovae led physicists that not only was the universe expanding, but the expansion was speeding up. In this article, we describe the evidence for an expanding universe and describe what physicists and cosmologists have learned in the intervening years. The target audience for this article is high school physics teachers and college physics professors at teaching institutions.

  9. Screw expander for light duty diesel engines

    Science.gov (United States)

    1983-01-01

    Preliminary selection and sizing of a positive displacement screw compressor-expander subsystem for a light-duty adiabatic diesel engine; development of a mathematical model to describe overall efficiencies for the screw compressor and expander; simulation of operation to establish overall efficiency for a range of design parameters and at given engine operating points; simulation to establish potential net power output at light-duty diesel operating points; analytical determination of mass moments of inertia for the rotors and inertia of the compressor-expander subsystem; and preparation of engineering layout drawings of the compressor and expander are discussed. As a result of this work, it was concluded that the screw compressor and expander designed for light-duty diesel engine applications are viable alternatives to turbo-compound systems, with acceptable efficiencies for both units, and only a moderate effect on the transient response.

  10. Miniature PT Cryocooler Activated by Resonant Piezoelectric Compressor and Passive Warm Expander

    Science.gov (United States)

    Sobol, S.; Grossman, G.

    2017-12-01

    A novel type of PZT-based compressor operating at mechanical resonance, suitable for pneumatically-driven Stirling-type cryocoolers, was presented at CEC-ICMC 2015. The detailed concept, analytical model and the test results on the preliminary prototype were reported earlier and presented at ICC17. Despite some mismatch between the impedances and insufficient structural stiffness, this compressor demonstrated the feasibility to drive our miniature Pulse Tube cryocooler MTSa, operating at 103 Hz and requiring an average PV power of 11 W, filling pressure of 40 Bar and a pressure ratio of 1.3. At ICC19 the prototype of a miniature passive warm expander (WE) was presented. The WE mechanism included a phase shifting piston suspended on a silicone diaphragm, a mass element, and a viscous damping system. Several technical drawbacks prevented perfect matching between the WE and MTSa; however, the presented prototype proved the ability to create any flow-to-pressure phase appropriate for a PT cryocooler. This paper concentrates on integration of the MTSa cryocooler with the recently modified PZT compressor operating at corrected mechanical resonance and the modified WE, which was also updated recently to match the MTSa requirements.

  11. Laser welding to expand the allowable gap in bore welding for ITER blanket hydraulic connection

    Energy Technology Data Exchange (ETDEWEB)

    Tanigawa, Hisashi, E-mail: tanigawa.hisashi@jaea.go.jp; Maruyama, Takahito; Noguchi, Yuto; Takeda, Nobukazu; Kakudate, Satoshi

    2015-10-15

    For application to bore welding of hydraulic connection in the ITER blanket module, laser welding presents the following benefits: low weld heat input is preferred for re-welding of the irradiated material. Its contactless process can intrinsically avoid a failure mode of the tool sticking on the weld. The exact requirements for pipe alignment were assessed in comparison with the assembly tolerance. The groove geometry was modified to expand the allowable initial gap. The groove was machined to be partially thick to obviate the filler wire. First, plates with partially thick grooves were welded to elucidate the preferred groove geometry and welding conditions. With the modified groove, the plates were welded for the initial gap of 1.0 mm. Then the groove geometry and welding conditions were adjusted based on results of pipe welding tests. By application of the additional 0.5-mm-thick and 2.5-mm-wide metal in the groove, pipes with an initial gap of 0.7 mm were welded successfully.

  12. A-coupled-expanding and distributional chaos

    International Nuclear Information System (INIS)

    Kim, Cholsan; Ju, Hyonhui; Chen, Minghao; Raith, Peter

    2015-01-01

    The concept of A-coupled-expanding maps is one of the more natural and useful ideas generalized from the horseshoe map which is commonly known as a criterion of chaos. It is well known that distributional chaos is one of the concepts which reflect strong chaotic behavior. In this paper, we focus on the relationship between A-coupled-expanding and distributional chaos. We prove two theorems which give sufficient conditions for a strictly A-coupled-expanding map to be distributionally chaotic in the senses of two kinds, where A is an m × m irreducible transition matrix

  13. Stability of expanded plasma focus

    International Nuclear Information System (INIS)

    Soliman, H.M.

    1994-01-01

    In this study, the stabilization of the expanded plasma focus formed by 4.5 kJ plasma focus device of Mather type by magnetic field is presented. The experimental results of the induced axial magnetic field and electric probe measurements of the expanded plasma focus show that, the plasma consists of three plasmoids, electron temperature measurements off the plasmoids at a point close to the muzzle are 26 eV, 30 eV and 27 eV respectively and the electron densities are 6.6 x 10 14 , 6.1 x 10 14 / cm 3 respectively. The presence of external axial magnetic field (B 2 = 1.6 kg) at the mid distance between the breech and the muzzle has a less effect on the stability of expanded focus and it causes a restriction for the plasma motion. the electron temperature of the three plasmoids are found to increase in that case by 23%, 18.5% respectively. When this axial magnetic field is applied at the muzzle end, it leads to a more stable expanded plasma focus which consists mainly of one plasmoid with electron temperature of 39 eV and density of 3.4 x 10 14 / cm 3 . 5 figs

  14. Expanding/Extending English: Interdisciplinarity and Internationalism.

    Science.gov (United States)

    Fleishman, Avrom

    1994-01-01

    Discusses the recent efforts to expand literary studies into numerous allied fields and the possible effects that such attempts toward interdisciplinarity and internationalism might have. Warns against possible negative consequences of interdisciplinary approaches. Calls for an expanded view of English as a field of study. (HB)

  15. Factors leading to tracheobronchial self-expandable metallic stent fracture.

    Science.gov (United States)

    Chung, Fu-Tsai; Lin, Shu-Min; Chen, Hao-Cheng; Chou, Chun-Liang; Yu, Chih-Teng; Liu, Chien-Ying; Wang, Chun-Hua; Lin, Horng-Chyuan; Huang, Chien-Da; Kuo, Han-Pin

    2008-11-01

    This retrospective study was to determine factors that contribute to self-expandable metallic stent fracture in patients with tracheobronchial disease. From 2001 to 2006, 139 patients (age, 62.1 +/- 15.4 years; range, 23-87 years) with benign (n = 62) and malignant (n = 77) tracheobronchial disease received 192 Ultraflex (Boston Scientific, Natick, Mass) self-expandable metallic stents (98 in patients with benign disease and 94 in patients with malignant disease). Seventeen fractured self-expandable metallic stents were found; the incidence was 12.2% (17/139 patients) among patients with tracheobronchial disease. Tortuous airway (odds ratio, 4.06; 95% confidence interval, 1.04-18.34; P = .04) independently predicted self-expandable metallic stent fracture. Most self-expandable metallic stent fractures (64.7%, 11/17) were detected 500 to 1000 days after self-expandable metallic stent implantation. Clinical presentations for patients with fractured self-expandable metallic stents included dyspnea exacerbation (70.6%, 12/17) and cough (23.5%, 4/17). Self-expandable metallic stent fracture is not uncommon in patients with tracheobronchial disease. Tortuous airway is an independent predictor for it. Although management of the fractured self-expandable metallic stent in our study was feasible and safe, self-expandable metallic stents should be restricted to a more select population.

  16. Neutrinos in an expanding Universe

    International Nuclear Information System (INIS)

    Wigmans, Richard

    2015-01-01

    The Universe contains several billion neutrinos for each nucleon. In this paper, we follow the history of these relic neutrinos as the Universe expanded. At present, their typical velocity is a few hundred km/s and, therefore, their spectra are affected by gravitational forces. This may have led to a phenomenon that could explain two of todays great mysteries: The large-scale structure of the Universe and the increasing rate at which it expands. (paper)

  17. Free-piston reciprocating cryogenic expander utilizing phase controller

    Science.gov (United States)

    Cha, Jeongmin; Park, Jiho; Kim, Kyungjoong; Jeong, Sangkwon

    2017-02-01

    In a free-piston expander which eliminates mechanical linkages, a prescribed behaviour of the free-piston movement is the key to an expander performance. In this paper, we have proposed an idea of reducing complexity of the free-piston expander. It is to replace both multiple solenoid valves and reservoirs that are indispensable in a previous machine with a combination of a single orifice-reservoir assembly. It functions as a phase controller like that of a pulse tube refrigerator so that it generates time-delay of pressure variation between the warm-end and the reservoir resulting in the intended expansion of the cold-end volume down to the pre-set reservoir pressure. The modeling of this unique free-piston reciprocating expander utilizing phase controller is developed to understand and predict the performance of the new-type expander. Additionally, the operating parameters are analysed at the specified conditions to enable one to develop a more efficient free-piston type cryogenic expander.

  18. New generation expandable sand screens

    OpenAIRE

    Syltøy, Christer

    2014-01-01

    Master's thesis in Petroleum engineering This thesis aims to give a general insight into sand control and various sorts of sand control measures and applications of sand control tools. Special focus will be given to expandable sand screens – a technology which came about in the late 1990’s through the use of flexible, expandable tubulars as base pipe in sand screens. More specifically Darcy’s Hydraulic Endurance Screens, a compliant sand screen system using hydraulic activation, and the fu...

  19. Propagation of truncated modified Laguerre-Gaussian beams

    Science.gov (United States)

    Deng, D.; Li, J.; Guo, Q.

    2010-01-01

    By expanding the circ function into a finite sum of complex Gaussian functions and applying the Collins formula, the propagation of hard-edge diffracted modified Laguerre-Gaussian beams (MLGBs) through a paraxial ABCD system is studied, and the approximate closed-form propagation expression of hard-edge diffracted MLGBs is obtained. The transverse intensity distribution of the MLGB carrying finite power can be characterized by a single bright and symmetric ring during propagation when the aperture radius is very large. Starting from the definition of the generalized truncated second-order moments, the beam quality factor of MLGBs through a hard-edged circular aperture is investigated in a cylindrical coordinate system, which turns out to be dependent on the truncated radius and the beam orders.

  20. Numerical investigation of two- and three-dimensional heat transfer in expander cycle engines

    Science.gov (United States)

    Burch, Robert L.; Cheung, Fan-Bill

    1993-01-01

    The concept of using tube canting for enhancing the hot-side convective heat transfer in a cross-stream tubular rocket combustion chamber is evaluated using a CFD technique in this study. The heat transfer at the combustor wall is determined from the flow field generated by a modified version of the PARC Navier-Stokes Code, using the actual dimensions, fluid properties, and design parameters of a split-expander demonstrator cycle engine. The effects of artificial dissipation on convergence and solution accuracy are investigated. Heat transfer results predicted by the code are presented. The use of CFD in heat transfer calculations is critically examined to demonstrate the care needed in the use of artificial dissipation for good convergence and accurate solutions.

  1. Effects of rapid maxillary expansion in cleft patients resulting from the use of two different expanders

    Directory of Open Access Journals (Sweden)

    Daniel Santos Fonseca Figueiredo

    Full Text Available ABSTRACT Introduction: The aim of this study was to evaluate the skeletal and dental effects of rapid maxillary expansion (RME in cleft patients using two types of expanders. Methods: Twenty unilateral cleft lip and palate patients were randomly divided into two groups, according to the type of expander used: (I modified Hyrax and (II inverted Mini-Hyrax. A pretreatment cone-beam computed tomographic image (T0 was taken as part of the initial orthodontic records and three months after RME as need for bone graft planning (T1. Results: In general, there was no significant difference among groups (p > 0.05. Both showed significant transverse maxillary expansion (p 0.05. There was greater crown than apical expansion. Maxillary posterior expansion tended to be larger than anterior opening (p 0.05. Conclusions: The appliances tested are effective for transverse expansion of the maxilla. However, these appliances should be better indicated to cleft cases also presenting posterior transverse discrepancy, since there was greater expansion in the posterior maxillary region than in the anterior one.

  2. Partition expanders

    Czech Academy of Sciences Publication Activity Database

    Gavinsky, Dmitry; Pudlák, Pavel

    2017-01-01

    Roč. 60, č. 3 (2017), s. 378-395 ISSN 1432-4350 R&D Projects: GA ČR GBP202/12/G061 Institutional support: RVO:67985840 Keywords : expanders * pseudorandomness * communication complexity Subject RIV: BA - General Mathematics OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 0.645, year: 2016 http://link.springer.com/article/10.1007%2Fs00224-016-9738-5

  3. A Modified Tactile Brush Algorithm for Complex Touch Gestures

    Energy Technology Data Exchange (ETDEWEB)

    Ragan, Eric [Texas A& M University

    2015-01-01

    Several researchers have investigated phantom tactile sensation (i.e., the perception of a nonexistent actuator between two real actuators) and apparent tactile motion (i.e., the perception of a moving actuator due to time delays between onsets of multiple actuations). Prior work has focused primarily on determining appropriate Durations of Stimulation (DOS) and Stimulus Onset Asynchronies (SOA) for simple touch gestures, such as a single finger stroke. To expand upon this knowledge, we investigated complex touch gestures involving multiple, simultaneous points of contact, such as a whole hand touching the arm. To implement complex touch gestures, we modified the Tactile Brush algorithm to support rectangular areas of tactile stimulation.

  4. Flow boiling in expanding microchannels

    CERN Document Server

    Alam, Tamanna

    2017-01-01

    This Brief presents an up to date summary of details of the flow boiling heat transfer, pressure drop and instability characteristics; two phase flow patterns of expanding microchannels. Results obtained from the different expanding microscale geometries are presented for comparison and addition to that, comparison with literatures is also performed. Finally, parametric studies are performed and presented in the brief. The findings from this study could help in understanding the complex microscale flow boiling behavior and aid in the design and implementation of reliable compact heat sinks for practical applications.

  5. Aortic annulus eccentricity before and after transcatheter aortic valve implantation: Comparison of balloon-expandable and self-expanding prostheses

    International Nuclear Information System (INIS)

    Schuhbaeck, Annika; Weingartner, Christina; Arnold, Martin; Schmid, Jasmin; Pflederer, Tobias; Marwan, Mohamed; Rixe, Johannes; Nef, Holger; Schneider, Christian; Lell, Michael; Uder, Michael; Ensminger, Stephan; Feyrer, Richard; Weyand, Michael; Achenbach, Stephan

    2015-01-01

    Highlights: • Post-implant geometry of catheter-based aortic valve prostheses is influenced by aortic valve calcification. • Balloon-expandable prostheses are more circular as compared to self-expanding prostheses. • The impact of post-implant geometry on valve function needs to be investigated. - Abstract: Introduction: The geometry of the aortic annulus and implanted transcatheter aortic valve prosthesis might influence valve function. We investigated the influence of valve type and aortic valve calcification on post-implant geometry of catheter-based aortic valve prostheses. Methods: Eighty consecutive patients with severe aortic valve stenosis (mean age 82 ± 6 years) underwent computed tomography before and after TAVI. Aortic annulus diameters were determined. Influence of prosthesis type and degree of aortic valve calcification on post-implant eccentricity were analysed. Results: Aortic annulus eccentricity was reduced in patients after TAVI (0.21 ± 0.06 vs. 0.08 ± 0.06, p < 0.0001). Post-TAVI eccentricity was significantly lower in 65 patients following implantation of a balloon-expandable prosthesis as compared to 15 patients who received a self-expanding prosthesis (0.06 ± 0.05 vs. 0.15 ± 0.07, p < 0.0001), even though the extent of aortic valve calcification was not different. After TAVI, patients with a higher calcium amount retained a significantly higher eccentricity compared to patients with lower amounts of calcium. Conclusions: Patients undergoing TAVI with a balloon-expandable prosthesis show a more circular shape of the implanted prosthesis as compared to patients with a self-expanding prosthesis. Eccentricity of the deployed prosthesis is affected by the extent of aortic valve calcification

  6. Entropy in an expanding universe

    International Nuclear Information System (INIS)

    Frautschi, S.

    1982-01-01

    The question of how the observed evolution of organized structures from initial chaos in the expanding universe can be reconciled with the laws of statistical mechanics is studied, with emphasis on effects of the expansion and gravity. Some major sources of entropy increase are listed. An expanding causal region is defined in which the entropy, though increasing, tends to fall further and further behind its maximum possible value, thus allowing for the development of order. The related questions of whether entropy will continue increasing without limit in the future, and whether such increase in the form of Hawking radiation or radiation from positronium might enable life to maintain itself permanently, are considered. Attempts to find a scheme for preserving life based on solid structures fail because events such as quantum tunneling recurrently disorganize matter on a very long but fixed time scale, whereas all energy sources slow down progressively in an expanding universe. However, there remains hope that other modes of life capable of maintaining themselves permanently can be found

  7. Note: Expanding the bandwidth of the ultra-low current amplifier using an artificial negative capacitor

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Kai, E-mail: kaixie@mail.xidian.edu.cn; Liu, Yan; Li, XiaoPing [School of Aerospace Science and Technology, Xidian University, Xi’an 710071 (China); Guo, Lixin [School of Physics and Optoelectronic Engineering, Xidian University, Xi’an 710071 (China); Zhang, Hanlu [School of Communication & Information Engineering, Xi’an University of Posts & Telecommunication, Xi’an 710121 (China)

    2016-04-15

    The bandwidth and low noise characteristics are often contradictory in ultra-low current amplifier, because an inevitable parasitic capacitance is paralleled with the high value feedback resistor. In order to expand the amplifier’s bandwidth, a novel approach was proposed by introducing an artificial negative capacitor to cancel the parasitic capacitance. The theory of the negative capacitance and the performance of the improved amplifier circuit with the negative capacitor are presented in this manuscript. The test was conducted by modifying an ultra-low current amplifier with a trans-impedance gain of 50 GΩ. The results show that the maximum bandwidth was expanded from 18.7 Hz to 3.3 kHz with more than 150 times of increase when the parasitic capacitance (∼0.17 pF) was cancelled. Meanwhile, the rise time decreased from 18.7 ms to 0.26 ms with no overshot. Any desired bandwidth or rise time within these ranges can be obtained by adjusting the ratio of cancellation of the parasitic and negative capacitance. This approach is especially suitable for the demand of rapid response to weak current, such as transient ion-beam detector, mass spectrometry analysis, and fast scanning microscope.

  8. Note: Expanding the bandwidth of the ultra-low current amplifier using an artificial negative capacitor.

    Science.gov (United States)

    Xie, Kai; Liu, Yan; Li, XiaoPing; Guo, Lixin; Zhang, Hanlu

    2016-04-01

    The bandwidth and low noise characteristics are often contradictory in ultra-low current amplifier, because an inevitable parasitic capacitance is paralleled with the high value feedback resistor. In order to expand the amplifier's bandwidth, a novel approach was proposed by introducing an artificial negative capacitor to cancel the parasitic capacitance. The theory of the negative capacitance and the performance of the improved amplifier circuit with the negative capacitor are presented in this manuscript. The test was conducted by modifying an ultra-low current amplifier with a trans-impedance gain of 50 GΩ. The results show that the maximum bandwidth was expanded from 18.7 Hz to 3.3 kHz with more than 150 times of increase when the parasitic capacitance (∼0.17 pF) was cancelled. Meanwhile, the rise time decreased from 18.7 ms to 0.26 ms with no overshot. Any desired bandwidth or rise time within these ranges can be obtained by adjusting the ratio of cancellation of the parasitic and negative capacitance. This approach is especially suitable for the demand of rapid response to weak current, such as transient ion-beam detector, mass spectrometry analysis, and fast scanning microscope.

  9. Solid expandable systems put deepwater targets within reach

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Roca, Eduardo [Enventure Global Technology L.L.C., Houston, TX (United States). Latin America; Fristch, Jerry [Enventure Global Technology L.L.C., Houston, TX (United States)

    2008-07-01

    Enabling technologies that take drilling operations to deeper objectives have made a significant impact on the practicality of many projects, especially deep water offshore targets. Increasing vertical depth and lateral reach requires adequate hole size to attain the desired objectives of the well bore. Solid expandable technology can maintain and retain hole size to address both the physical limitations and the economic feasibility of deep water operations. With each and every casing point, the potential for adequate hole size at total depth (TD) decreases. Solid expandable open hole liners and single-diameter systems reduce and eliminate, respectively, the well bore tapering that dictates hole size at TD and subsequent completion size. Successful mitigation of this tapering, whether through the entire well bore or through select zones, enables operators to gain access to previously unreachable reserves. Solid expandable systems have proven to be reliable and effective with over 1,000 installations in a myriad of conditions and environments worldwide. To date, over 115 of those applications have been in deep water environments. The current operating envelope for solid expandable systems include the deepest installation at {approx}28,750 ft (8,763 m) and the longest at 6,867 ft (2,083 m) in water depth over 3,150 ft (960 m). This record-length application consisted of an open hole liner installed and expanded in a single run. This paper will discuss the effectiveness of solid expandable systems in deep water operations and how the technology brings value to offshore projects especially when planned into the initial design. Case histories will be used to further illustrate the features, advantages, and benefits of expandable technology. In addition, this paper will examine the state of the solid expandable technology and its continuing evolution to provide even more drilling solutions. (author)

  10. A free-surface lattice Boltzmann method for modelling the filling of expanding cavities by Bingham fluids.

    Science.gov (United States)

    Ginzburg, Irina; Steiner, Konrad

    2002-03-15

    The filling process of viscoplastic metal alloys and plastics in expanding cavities is modelled using the lattice Boltzmann method in two and three dimensions. These models combine the regularized Bingham model for viscoplastic fluids with a free-interface algorithm. The latter is based on a modified immiscible lattice Boltzmann model in which one species is the fluid and the other one is considered to be a vacuum. The boundary conditions at the curved liquid-vacuum interface are met without any geometrical front reconstruction from a first-order Chapman-Enskog expansion. The numerical results obtained with these models are found in good agreement with available theoretical and numerical analysis.

  11. Novel power MOSFET-based expander for high frequency ultrasound systems.

    Science.gov (United States)

    Choi, Hojong; Shung, K Kirk

    2014-01-01

    The function of an expander is to obstruct the noise signal transmitted by the pulser so that it does not pass into the transducer or receive electronics, where it can produce undesirable ring-down in an ultrasound imaging application. The most common type is a diode-based expander, which is essentially a simple diode-pair, is widely used in pulse-echo measurements and imaging applications because of its simple architecture. However, diode-based expanders may degrade the performance of ultrasonic transducers and electronic components on the receiving and transmitting sides of the ultrasound systems, respectively. Since they are non-linear devices, they cause excessive signal attenuation and noise at higher frequencies and voltages. In this paper, a new type of expander that utilizes power MOSFET components, which we call a power MOSFET-based expander, is introduced and evaluated for use in high frequency ultrasound imaging systems. The performance of a power MOSFET-based expander was evaluated relative to a diode-based expander by comparing the noise figure (NF), insertion loss (IL), total harmonic distortion (THD), response time (RT), electrical impedance (EI) and dynamic power consumption (DPC). The results showed that the power MOSFET-based expander provided better NF (0.76 dB), IL (-0.3 dB) and THD (-62.9 dB), and faster RT (82 ns) than did the diode-based expander (NF (2.6 dB), IL (-1.4 dB), THD (-56.0 dB) and RT (119 ns)) at 70 MHz. The -6 dB bandwidth and the peak-to-peak voltage of the echo signal received by the transducer using the power MOSFET-based expander improved by 17.4% and 240% compared to the diode-based expander, respectively. The new power MOSFET-based expander was shown to yield lower NF, IL and THD, faster RT and lower ring down than the diode-based expander at the expense of higher dynamic power consumption. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Heat shrinkage of electron beam modified EVA

    International Nuclear Information System (INIS)

    Datta, S.K.; Chaki, T.K.; Bhowmick, A.K.

    1997-01-01

    Heat shrinkage of electron beam modified ethylene vinyl acetate copolymer (EVA) has been investigated over a range of times, temperatures, stretching, irradiation doses and trimethylolpropane trimethacrylate (TMPTMA) levels. The irradiated (radiation dose 50 kGy and TMPTMA level 1%) and stretched (100% elongation) sample shrinks to a maximum level when kept at 453K temperature for 60 s. The heat shrinkage of samples irradiated with radiation doses of 20, 50, 100 and 150 kGy increases sharply with increasing stretching in the initial stage. Amnesia rating decreases with increasing radiation dose and TMPTMA level as well as gel content. The high radiation dose and TMPTMA level lower the heat shrinkage due to the chain scission. The effect of temperature at which extension is carried out on heat shrinkage is marginal. The irradiated (radiation dose 50 kGy and TMPTMA level 1%) EVA tubes of different dimensions expanded in a laboratory grade tube expander show similar behaviour at 453K and 60 s. The X-ray and DSC studies reveal that the crystallinity increases on stretching due to orientation of chains and it decreases to a considerable extent on heat shrinking. The theoretical and experimental values of heat shrinkage for tubes and rectangular strips are in good accord, when the radiation dose is 50 kGy and TMPTMA level 1%. (author)

  13. Heat shrinkage of electron beam modified EVA

    Energy Technology Data Exchange (ETDEWEB)

    Datta, S.K.; Chaki, T.K.; Bhowmick, A.K. [Indian Institute of Technology, Kharagpur (India). Rubber Technology Center; Tikku, V.K.; Pradhan, N.K. [NICCO Corporation Ltd., (Cable Div.), Calcutta (India)

    1997-10-01

    Heat shrinkage of electron beam modified ethylene vinyl acetate copolymer (EVA) has been investigated over a range of times, temperatures, stretching, irradiation doses and trimethylolpropane trimethacrylate (TMPTMA) levels. The irradiated (radiation dose 50 kGy and TMPTMA level 1%) and stretched (100% elongation) sample shrinks to a maximum level when kept at 453K temperature for 60 s. The heat shrinkage of samples irradiated with radiation doses of 20, 50, 100 and 150 kGy increases sharply with increasing stretching in the initial stage. Amnesia rating decreases with increasing radiation dose and TMPTMA level as well as gel content. The high radiation dose and TMPTMA level lower the heat shrinkage due to the chain scission. The effect of temperature at which extension is carried out on heat shrinkage is marginal. The irradiated (radiation dose 50 kGy and TMPTMA level 1%) EVA tubes of different dimensions expanded in a laboratory grade tube expander show similar behaviour at 453K and 60 s. The X-ray and DSC studies reveal that the crystallinity increases on stretching due to orientation of chains and it decreases to a considerable extent on heat shrinking. The theoretical and experimental values of heat shrinkage for tubes and rectangular strips are in good accord, when the radiation dose is 50 kGy and TMPTMA level 1%. (author).

  14. Enhanced Stormwater Contaminant Removal Using Tree Filters And Modified Sorbents

    Science.gov (United States)

    Schifman, L. A.; Kasaraneni, V. K.; Boving, T. B.; Oyanedel-Craver, V.

    2012-12-01

    Stormwater runoff, particularly in urban areas, contains several groups of contaminants that negatively impact surface- and groundwater quality if left untreated. Contaminants in runoff are often addressed by structural best management practices (BMP) that capture and treat runoff before discharging it. Many BMPs, such as tree filters, act as primary filtration devices that attenuate total suspended solids, nutrients, and heavy metals from runoff; but typically these BMPs are not designed to treat bacteria and have only minor petroleum hydrocarbon (PH) treatment capabilities. To address this shortcoming, three materials (red cedar wood chips, expanded shale, and crushed concrete) were modified with either Quaternary Ammonium Silane (QAS) or Silver Nanoparticles (AgNPs) to provide antimicrobial properties to the matrix and/or exploit their affinity to sorb PH, particularly polycyclic aromatic hydrocarbons (PAH). Results show that of the three materials investigated, wood chips exhibit the highest sorption capacity for QAS, making this material favorable for treating bacteria, while at the same time attenuating PAHs by sorption processes. In case of AgNP amendments to wood, less uptake and more desorption from the wood matrix was observed. Relative to wood, expanded shale and crushed concrete exhibited less affinity for QAS (results for AgNPs are pending). Currently, batch isotherm and unsaturated flow column studies are under way to determine the performance of the amended materials with regard to removal of bacteria, nutrients, heavy metals, and PAH from artificially contaminated runoff. In this presentation, the contaminant removal efficiency of all modified and unmodified materials will be discussed on the background of how these materials may find use in enhanced treatment of stormwater in tree filter BMPs.

  15. Origin and dynamics of expanding neutral hydrogen supershells

    International Nuclear Information System (INIS)

    Kolesnik, I.G.; Silich, S.A.

    1987-01-01

    The evolutionary model of expanding supershells regulated by induced star formation is proposed. It is suggested that giant expanding shells are formed n superclouds at late evolutionary stage of star complexes. To understand the dynamics of the most huge supershells it is necessary to take into account that expanding shells can trigger star formation in cold dense pre-exosting cloudlets. Efficiency of induced star formation must be less than one percent to fit observational properties of supershells

  16. Seal-less cryogenic expander

    International Nuclear Information System (INIS)

    Faria, L.E.; Christopher, E.H.

    1987-01-01

    In an expander for use in a split Stirling cycle refrigeration system of the type wherein a displacer moves with reciprocating motion inside an expander housing, and wherein a plunger force and a regenerator force are formed on the displacer, the plunger force cyclically varying and having a time of minimum and maximum plunger force amplitude, and the regenerator force cyclically varying and having a time of minimum and maximum regenerator force amplitude, the improvement is described comprising: (a) means for maintaining displacer forces, such that the maximum plunger force amplitude is substantially equal to the maximum regenerator force amplitude; and (b) means for adjusting a time difference, the time difference being the time between the time of maximum plunger force and the time of maximum regenerator force such that a measure of the cooling power of the refrigeration system is maximized

  17. Semiclassical expanding discrete space-times

    International Nuclear Information System (INIS)

    Cobb, W.K.; Smalley, L.L.

    1981-01-01

    Given the close ties between general relativity and geometry one might reasonably expect that quantum effects associated with gravitation might also be tied to the geometry of space-time, namely, to some sort of discreteness in space-time itself. In particular it is supposed that space-time consists of a discrete lattice of points rather than the usual continuum. Since astronomical evidence seems to suggest that the universe is expanding, the lattice must also expand. Some of the implications of such a model are that the proton should presently be stable, and the universe should be closed although the mechanism for closure is quantum mechanical. (author)

  18. Refrigeration generation using expander-generator units

    Science.gov (United States)

    Klimenko, A. V.; Agababov, V. S.; Koryagin, A. V.; Baidakova, Yu. O.

    2016-05-01

    The problems of using the expander-generator unit (EGU) to generate refrigeration, along with electricity were considered. It is shown that, on the level of the temperatures of refrigeration flows using the EGU, one can provide the refrigeration supply of the different consumers: ventilation and air conditioning plants and industrial refrigerators and freezers. The analysis of influence of process parameters on the cooling power of the EGU, which depends on the parameters of the gas expansion process in the expander and temperatures of cooled environment, was carried out. The schematic diagram of refrigeration generation plant based on EGU is presented. The features and advantages of EGU to generate refrigeration compared with thermotransformer of steam compressive and absorption types were shown, namely: there is no need to use the energy generated by burning fuel to operate the EGU; beneficial use of the heat delivered to gas from the flow being cooled in equipment operating on gas; energy production along with refrigeration generation, which makes it possible to create, using EGU, the trigeneration plants without using the energy power equipment. It is shown that the level of the temperatures of refrigeration flows, which can be obtained by using the EGU on existing technological decompression stations of the transported gas, allows providing the refrigeration supply of various consumers. The information that the refrigeration capacity of an expander-generator unit not only depends on the parameters of the process of expansion of gas flowing in the expander (flow rate, temperatures and pressures at the inlet and outlet) but it is also determined by the temperature needed for a consumer and the initial temperature of the flow of the refrigeration-carrier being cooled. The conclusion was made that the expander-generator units can be used to create trigeneration plants both at major power plants and at small energy.

  19. Strength analysis of expandable tubulars for well applications

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, A.C.C. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Fonseca, C.E. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Netto, T.A. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE)

    2008-07-01

    Solid expandable tube technology has many advantages when compared to conventional wells. The expansion of tubes in situ allows developing reserves in many of the challenging scenarios found in oil industry, as pre-salt layer, HPHT wells, deep reservoirs, or ultra-deep water. Besides, this procedure has good compatibility with directional and horizontal wells and facilitates side-tracks operations. Although the expansion of tubes is very attractive, a better understanding of its influence on the tube mechanical strength is necessary. In this work, experimental tests and numerical analyses were performed in order to determine the effect of parameters such as diameter-to-thickness ratio and expansion rate on the collapse resistance of expandable tubes. An experimental apparatus was designed and built to reproduce full-scale tube expansion. Three 2 meter long specimens were expanded 10% their original diameters and subjected to hydrostatic pressure inside a vessel until collapse. Three non-expanded tubes were also tested for comparison. At the same time, non-linear numerical models were developed using the finite element method. After calibration, they were used to further analyze the mechanical behavior of solid expandable tubes and the influence of expansion on its resistance against collapse. (author)

  20. An Isothermal Steam Expander for an Industrial Steam Supplying System

    Directory of Open Access Journals (Sweden)

    Chen-Kuang Lin

    2015-01-01

    Full Text Available Steam is an essential medium used in the industrial process. To ensure steam quality, small and middle scale boilers are often adopted. However, because a higher steam pressure (compared to the necessary steam pressure is generated, the boiler’s steam pressure will be reduced via a pressure regulator before the steam is directed through the process. Unfortunately, pressure is somewhat wasted during the reducing process. Therefore, in order to promote energy efficiency, a pressure regulator is replaced by a steam expander. With this steam expander, the pressure will be transformed into mechanical energy and extracted during the expansion process. A new type of isothermal steam expander for an industrial steam supplying system will be presented in the paper. The isothermal steam expander will improve the energy efficiency of a traditional steam expander by replacing the isentropic process with an isothermal expansion process. With this, steam condensation will decrease, energy will increase, and steam quality will be improved. Moreover, the mathematical model of the isothermal steam expander will be established by using the Schmidt theory, the same principle used to analyze Stirling engines. Consequently, by verifying the correctness of the theoretical model for the isothermal steam expander using experimental data, a prototype of 100 c.c. isothermal steam expander is constructed.

  1. Numerical modelling of multi-vane expander operating conditions in ORC system

    Science.gov (United States)

    Rak, Józef; Błasiak, Przemysław; Kolasiński, Piotr

    2017-11-01

    Multi-vane expanders are positive displacement volumetric machines which are nowadays considered for application in micro-power domestic ORC systems as promising alternative to micro turbines and other volumetric expanders. The multi-vane expander features very simple design, low gas flow capacity, low expansion ratios, an advantageous ratio of the power output to the external dimensions and are insensitive to the negative influence of the gas-liquid mixture expansion. Moreover, the multi-vane expander can be easily hermetically sealed, which is one of the key issues in the ORC system design. A literature review indicates that issues concerning the application of multi-vane expanders in such systems, especially related to operating of multi-vane expander with different low-boiling working fluids, are innovative, not fully scientifically described and have the potential for practical implementation. In this paper the results of numerical investigations on multi-vane expander operating conditions are presented. The analyses were performed on three-dimensional numerical model of the expander in ANSYS CFX software. The numerical model of the expander was validated using the data obtained from the experiment carried out on a lab test-stand. Then a series of computational analysis were performed using expanders' numerical model in order to determine its operating conditions under various flow conditions of different working fluids.

  2. MODIFIED GYPSUM BINDER

    Directory of Open Access Journals (Sweden)

    KONDRATEVA N. V.

    2017-02-01

    Full Text Available Summary. Statement of the problem. A disadvantage of the gypsum binder is the limited water resistance of products that historically led to the use of gypsum products mostly for internal construction and finishing works. To regulate the process of hydration and structure formation of the use of chemical additives that are introduced with the mixing water or in the production of the binder. As a rule, substances that increase the solubility of the gypsum binder referred to as the hardening accelerator, and substances which retard the solubility of the inhibitors of hardening of the mixture. Most accelerators and retarders hardening affect adversely on the final strength of the mixture. More effective impact on gypsum binder additives have plasticizers. The purpose of the article. Getting gypsum binder modified with the aim of improving its water resistance and improvement of some technological factors (the time of hardening, water gypsum ratio, etc. would reduce its shortcomings and expand the scope of application of the binder. Conclusion. The result of the research reviewed changes in the basic properties of the gypsum binder with the introduction of additives, plasticizers, and selected the most effective supplements to significantly reduce water gypsum ratio, to improve strength properties and to obtain gypsum binder more dense structure.

  3. Expanded-bed chromatography in primary protein purification.

    Science.gov (United States)

    Anspach, F B; Curbelo, D; Hartmann, R; Garke, G; Deckwer, W D

    1999-12-31

    Chromatography in stable expanded beds enables proteins to be recovered directly from cultivations of microorganisms or cells and preparations of disrupted cells, without the need for prior removal of suspended solids. The general performance of an expanded bed is comparable to a packed bed owing to reduced mixing of the adsorbent particles in the column. However, optimal operating conditions are more restricted than in a packed bed due to the dependence of bed expansion on the size and density of the adsorbent particles as well as the viscosity and density of the feedstock. The feedstock composition may become the most limiting restriction owing to interactions of adsorbent particles with cell surfaces, DNA and other substances, leading to their aggregation and consequently to bed instabilities and channeling. Despite these difficulties, expanded-bed chromatography has found widespread applications in the large scale purification of proteins from mammalian cell and microbial feedstocks in industrial bioprocessing. The basics and implementation of expanded-bed chromatography, its advantages as well as problems encountered in the use of this technique for the direct extraction of proteins from unclarified feedstocks are addressed.

  4. First order phase transition of expanding matter and its fragmentation

    International Nuclear Information System (INIS)

    Chikazumi, Shinpei; Iwamoto, Akira

    2002-01-01

    Using an expanding matter model with a Lennard-Jones potential, the instability of the expanding system is investigated. The pressure, the temperature, and the density fluctuations are calculated as functions of density during the time evolution of the expanding matter, which are compared to the coexistence curve calculated by the Gibbs ensemble. The expanding matter undergoes the first order phase transition in the limit of the quasistatic expansion. The resultant fragment mass distributions are also investigated. (author)

  5. Discontinuing disease-modifying therapy in progressive multiple sclerosis: can we stop what we have started?

    LENUS (Irish Health Repository)

    Lonergan, Roisin

    2012-02-01

    Disease-modifying therapy is ineffective in disabled patients (Expanded Disability Status Scale [EDSS] > 6.5) with secondary progressive multiple sclerosis (MS) without relapses, or in primary progressive MS. Many patients with secondary progressive MS who initially had relapsing MS continue to use disease-modifying therapies. The enormous associated costs are a burden to health services. Regular assessment is recommended to guide discontinuation of disease-modifying therapies when no longer beneficial, but this is unavailable to many patients, particularly in rural areas. The objectives of this study are as follows: 1. To observe use of disease-modifying therapies in patients with progressive multiple sclerosis and EDSS > 6.5. 2. To examine approaches used by a group of international MS experts to stopping-disease modifying therapies in patients with secondary progressive MS without relapses. During an epidemiological study in three regions of Ireland (southeast Dublin city, and Wexford and Donegal Counties), we recorded details of disease-modifying therapies in patients with progressive MS and EDSS > 6.5. An e-questionnaire was sent to 26 neurologists with expert knowledge of MS, asking them to share their approach to stopping disease-modifying therapies in patients with secondary progressive MS. Three hundred and thirty-six patients were studied: 88 from southeast Dublin, 99 from Wexford and 149 from Donegal. Forty-four had EDSS > 6.5: 12 were still using disease-modifying therapies. Of the surveyed neurologists, 15 made efforts to stop disease-modifying therapies in progressive multiple sclerosis, but most did not insist. A significant proportion (12 of 44 patients with progressive MS and EDSS > 6.5) was considered to be receiving therapy without benefit. Eleven of the 12 were from rural counties, reflecting poorer access to neurology services. The costs of disease-modifying therapies in this group (>170,000 euro yearly) could be re-directed towards development

  6. Grazing incidence beam expander

    Energy Technology Data Exchange (ETDEWEB)

    Akkapeddi, P.R.; Glenn, P.; Fuschetto, A.; Appert, Q.; Viswanathan, V.K.

    1985-01-01

    A Grazing Incidence Beam Expander (GIBE) telescope is being designed and fabricated to be used as an equivalent end mirror in a long laser resonator cavity. The design requirements for this GIBE flow down from a generic Free Electron Laser (FEL) resonator. The nature of the FEL gain volume (a thin, pencil-like, on-axis region) dictates that the output beam be very small. Such a thin beam with the high power levels characteristic of FELs would have to travel perhaps hundreds of meters or more before expanding enough to allow reflection from cooled mirrors. A GIBE, on the other hand, would allow placing these optics closer to the gain region and thus reduces the cavity lengths substantially. Results are presented relating to optical and mechanical design, alignment sensitivity analysis, radius of curvature analysis, laser cavity stability analysis of a linear stable concentric laser cavity with a GIBE. Fabrication details of the GIBE are also given.

  7. The Expanded Large Scale Gap Test

    Science.gov (United States)

    1987-03-01

    NSWC TR 86-32 DTIC THE EXPANDED LARGE SCALE GAP TEST BY T. P. LIDDIARD D. PRICE RESEARCH AND TECHNOLOGY DEPARTMENT ’ ~MARCH 1987 Ap~proved for public...arises, to reduce the spread in the LSGT 50% gap value.) The worst charges, such as those with the highest or lowest densities, the largest re-pressed...Arlington, VA 22217 PE 62314N INS3A 1 RJ14E31 7R4TBK 11 TITLE (Include Security CIlmsilficatiorn The Expanded Large Scale Gap Test . 12. PEIRSONAL AUTHOR() T

  8. Synthesis and Evaluation of Zeolite Surface-Modified Perlite

    Directory of Open Access Journals (Sweden)

    Kasai Makoto

    2017-01-01

    Full Text Available Perlite is volcanic glass mainly composed of amorphous aluminum silicate, mainly composed SiO2 and Al2O3 with less impurities such as heavy metals. Amorphous (glassy perlite is used in lightweight aggregate and insulation. In addition, it has also been used as a filter aid by grinding the expanded perlite. However, it has not been used as environmental cleanup materials, because the ion exchange capacity of the perlite is very low. In this study, we tried to synthesize the hybrid filter aid with chemical adsorption capacity by synthesizing the zeolite on the surface of the perlite. As a result, by using the hydrothermal synthesis method, zeolite surface modified perlite was synthesized in which the LTA type zeolites were generated on the surface of the perlite.

  9. Numerical modelling of multi-vane expander operating conditions in ORC system

    Directory of Open Access Journals (Sweden)

    Rak Józef

    2017-01-01

    Full Text Available Multi-vane expanders are positive displacement volumetric machines which are nowadays considered for application in micro-power domestic ORC systems as promising alternative to micro turbines and other volumetric expanders. The multi-vane expander features very simple design, low gas flow capacity, low expansion ratios, an advantageous ratio of the power output to the external dimensions and are insensitive to the negative influence of the gas-liquid mixture expansion. Moreover, the multi-vane expander can be easily hermetically sealed, which is one of the key issues in the ORC system design. A literature review indicates that issues concerning the application of multi-vane expanders in such systems, especially related to operating of multi-vane expander with different low-boiling working fluids, are innovative, not fully scientifically described and have the potential for practical implementation. In this paper the results of numerical investigations on multi-vane expander operating conditions are presented. The analyses were performed on three-dimensional numerical model of the expander in ANSYS CFX software. The numerical model of the expander was validated using the data obtained from the experiment carried out on a lab test-stand. Then a series of computational analysis were performed using expanders' numerical model in order to determine its operating conditions under various flow conditions of different working fluids.

  10. Intercalation of diclofenac in modified Zn/Al hydrotalcite-like preparation

    Science.gov (United States)

    Heraldy, E.; Suprihatin, R. W.; Pranoto

    2016-02-01

    The intercalation of a pharmaceutically active material diclofenac into modified Zn/Al Hydrotalcite-like (Zn/Al HTlc) preparation has been investigated by the coprecipitation and ion exchange method, respectively. The synthetic materials were characterized using X- Ray Diffraction (XRD); Fourier transforms infrared spectroscopy (FTIR); Scanning Electron Microscope (SEM); X-Ray Fluorescence (XRF) and surface area analyzer. The results show that the basal spacing of the product was expanded to 11.03 A for direct synthesis and 10.68 A for indirect synthesis, suggesting that diclofenac anion was intercalated into Zn/Al HTlc and arranged in a tilted bilayer fashion and the specific surface area of material increased after the intercalation of diclofenac.

  11. Comprehensive Approach for Identifying the T Cell Subset Origin of CD3 and CD28 Antibody-Activated Chimeric Antigen Receptor-Modified T Cells.

    Science.gov (United States)

    Schmueck-Henneresse, Michael; Omer, Bilal; Shum, Thomas; Tashiro, Haruko; Mamonkin, Maksim; Lapteva, Natalia; Sharma, Sandhya; Rollins, Lisa; Dotti, Gianpietro; Reinke, Petra; Volk, Hans-Dieter; Rooney, Cliona M

    2017-07-01

    The outcome of therapy with chimeric Ag receptor (CAR)-modified T cells is strongly influenced by the subset origin of the infused T cells. However, because polyclonally activated T cells acquire a largely CD45RO + CCR7 - effector memory phenotype after expansion, regardless of subset origin, it is impossible to know which subsets contribute to the final T cell product. To determine the contribution of naive T cell, memory stem T cell, central memory T cell, effector memory T cell, and terminally differentiated effector T cell populations to the CD3 and CD28-activated CAR-modified T cells that we use for therapy, we followed the fate and function of individually sorted CAR-modified T cell subsets after activation with CD3 and CD28 Abs (CD3/28), transduction and culture alone, or after reconstitution into the relevant subset-depleted population. We show that all subsets are sensitive to CAR transduction, and each developed a distinct T cell functional profile during culture. Naive-derived T cells showed the greatest rate of proliferation but had more limited effector functions and reduced killing compared with memory-derived populations. When cultured in the presence of memory T cells, naive-derived T cells show increased differentiation, reduced effector cytokine production, and a reduced reproliferative response to CAR stimulation. CD3/28-activated T cells expanded in IL-7 and IL-15 produced greater expansion of memory stem T cells and central memory T cell-derived T cells compared with IL-2. Our strategy provides a powerful tool to elucidate the characteristics of CAR-modified T cells, regardless of the protocol used for expansion, reveals the functional properties of each expanded T cell subset, and paves the way for a more detailed evaluation of the effects of manufacturing changes on the subset contribution to in vitro-expanded T cells. Copyright © 2017 by The American Association of Immunologists, Inc.

  12. Radiotherapy and breast reconstruction: complications and cosmesis with TRAM versus tissue expander/implant

    International Nuclear Information System (INIS)

    Chawla, Ashish K.; Kachnic, Lisa A.; Taghian, Alphonse G.; Niemierko, Andrzej; Zapton, Daniel T.; Powell, Simon N.

    2002-01-01

    Purpose: Radiotherapy (RT) has an important role in breast cancer treatment after modified radical mastectomy. Many of these patients also undergo breast reconstruction. We reviewed our institutions' experience to determine the outcome of patients treated with breast reconstruction and RT. Methods and Materials: Between 1981 and 1999, 48 breast cancer patients underwent modified radical mastectomy, breast reconstruction, and ipsilateral breast RT during their treatment course. Reconstruction either preceded or followed RT. Autologous reconstruction with a transverse rectus abdominus myocutaneous (TRAM) flap was performed in 30 patients, and 18 underwent expander and implant (E/I) reconstruction. The primary endpoint was the quality of the reconstructed, irradiated breast, as measured by analyzing the actuarial incidence of complications. The cosmetic outcome was also assessed by multidisciplinary review of the follow-up visits. Results: The median follow-up from reconstruction was 32 months. The actuarial 2-year complication rate was 53% for patients receiving E/I vs. 12% for those receiving TRAM reconstruction (p<0.01). No other patient or treatment-related factors had a significant impact on complications. The cosmetic outcome was also significantly better in the TRAM subgroup than in the E/I subgroup. Conclusion: The tolerance and cosmetic outcome of breast reconstruction for breast cancer patients in irradiated sites depends significantly on the type of reconstruction used

  13. Conference Offers Girls Opportunity to Expand Career Horizons

    Science.gov (United States)

    Offers Girls Opportunity to Expand Career Horizons For more information contact: e:mail: Public Affairs Golden, Colo., Feb. 11, 1997 -- Expanding Your Horizons, a conference for girls grades 6 - 9 and Employed Women, Girls Incorporated of Metro Denver, King Soopers, McDonalds, the TCI Adult Program and the

  14. Development of cryogenic free-piston reciprocating expander utilizing phase controller

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Jeong Min; Park, Ji Ho; Kim, Kyung Joong; Jeong, Sang Kwon [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2016-06-15

    A free-piston reciprocating expander is a device which operates without any mechanical linkage to a stationary part. Since the motion of the floating piston is only controlled by the pressure difference at two ends of the piston, this kind of expander may indispensably require a sophisticated active control system equipped with multiple valves and reservoirs. In this paper, we have suggested a novel design that can further reduce complexity of the previously developed cryogenic free-piston expander configuration. It is a simple replacement of both multiple valves and reservoirs by a combination of an orifice valve and a reservoir. The functional characteristic of the integrated orifice-reservoir configuration is similar to that of a phase controller applied in a pulse tube refrigerator so that we designate the one as a phase controller. Depending on the orifice valve size in the phase controller, the different PV work which affects the expander performance is generated. The numerical model of this unique free-piston reciprocating expander utilizing a phase controller is established to understand and analyze quantitatively the performance variation of the expander under different valve timing and orifice valve size. The room temperature experiments are carried out to examine the performance of this newly developed cryogenic expander.

  15. Development of cryogenic free-piston reciprocating expander utilizing phase controller

    International Nuclear Information System (INIS)

    Cha, Jeong Min; Park, Ji Ho; Kim, Kyung Joong; Jeong, Sang Kwon

    2016-01-01

    A free-piston reciprocating expander is a device which operates without any mechanical linkage to a stationary part. Since the motion of the floating piston is only controlled by the pressure difference at two ends of the piston, this kind of expander may indispensably require a sophisticated active control system equipped with multiple valves and reservoirs. In this paper, we have suggested a novel design that can further reduce complexity of the previously developed cryogenic free-piston expander configuration. It is a simple replacement of both multiple valves and reservoirs by a combination of an orifice valve and a reservoir. The functional characteristic of the integrated orifice-reservoir configuration is similar to that of a phase controller applied in a pulse tube refrigerator so that we designate the one as a phase controller. Depending on the orifice valve size in the phase controller, the different PV work which affects the expander performance is generated. The numerical model of this unique free-piston reciprocating expander utilizing a phase controller is established to understand and analyze quantitatively the performance variation of the expander under different valve timing and orifice valve size. The room temperature experiments are carried out to examine the performance of this newly developed cryogenic expander

  16. Crystallization degree change of expanded graphite by milling and annealing

    International Nuclear Information System (INIS)

    Tang Qunwei; Wu Jihuai; Sun Hui; Fang Shijun

    2009-01-01

    Expanded graphite was ball milled with a planetary mill in air atmosphere, and subsequently thermal annealed. The samples were characterized by using X-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM) and thermal gravimetric analysis (TGA). It was found that in the milling initial stage (less than 12 h), the crystallization degree of the expanded graphite declined gradually, but after milling more than 16 h, a recrystallization of the expanded graphite toke place, and ordered nanoscale expanded graphite was formed gradually. In the annealing initial stage, the non-crystallization of the graphite occurred, but, beyond an annealing time, recrystallizations of the graphite arise. Higher annealing temperature supported the recrystallization. The milled and annealed expanded graphite still preserved the crystalline structure as raw material and hold high thermal stability.

  17. Metallic stent for the treatment of iliac arterial stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hyung; Chung, Jin Wook; Han, Joon Koo; Suh, Chul Soo; Yoo, Jae Wook; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of); Song, Chi Sung [Seoul City Boramae Hospital, Seoul (Korea, Republic of)

    1993-07-15

    In order to study the clinical efficacy of the metallic stent of the treatment of iliac arterial stenosis, the clinical and arteriographic findings of the 8 patients were retrospectively reviewed. All 8 patients were males with an age of 51 to 79. The Fontaine class for the functional status of lower extremities was II in 4 patients, III in 3 patents and IV in 1 patient. Self expandable Gianturco stent was inserted of in 7 iliac arteries and balloon expandable Palmaz stent was inserted in 2 iliac arteries in the 8 patients. The indications for the metallic stent application were localized dissection with significant residual stenosis in 6 sites, recoiling due to calcification in one case and eccentricity of the stenosislesionin 2 sites. The deployment of the metallic stent was successful in all the cases to maintain the patency of iliac arteries with residual stenosis less than 30%. The Fontaine class was improved to 1 in 6 patients, IIa in 1 patient and IIb in another one. During the follow up period of 3 to 14 month, none except one developed recurrence of the symptom. On the basis of our experience, we believe that metallic stent is safe and effective for the treatment of iliac arterial stenosis. However, we think that it is a complementary measure to the percutaneous transluminal angioplasty. The comparative study between different types of metallic stent and the long term effect should be investigated further.

  18. Synthesis and characterization of Fullerene modified ZnAlTi-LDO in photo-degradation of Bisphenol A under simulated visible light irradiation

    International Nuclear Information System (INIS)

    Ju, Liting; Wu, Pingxiao; Lai, Xiaolin; Yang, Shanshan; Gong, Beini; Chen, Meiqing

    2017-01-01

    In this study, ZnAlTi layered double hydroxide (ZnAlTi-LDH) combined with fullerene (C 60 ) was fabricated by the urea method, and calcined under vacuum atmosphere to obtain nanocomposites of C 60 -modified ZnAlTi layered double oxide (ZnAlTi-LDO). The morphology, structure and composition of the nanocomposites were analyzed by Scanning Electron Microscopy, High-resolution transmission electron microscopy, X-ray diffraction patterns, Fourier transform infrared and specific surface area. The UV-vis diffuse reflectance spectra indicated that the incorporation of C 60 expanded the absorption of ZnAlTi-LDO to visible-light region. The photo-degradation experiment was conducted by using a series of C 60 modified ZnAlTi-LDO with different C 60 weight percentage to degrade Bisphenol A (BPA) under simulated visible light irradiation. In this experiment, the degradation rate of C 60 modified ZnAlTi-LDO in photo-degradation of BPA under simulated visible light irradiation was over 80%. The intermediates formed in the degradation of BPA process by using LDO/C 60 -5% were 4-hydroxyphenyl-2-propanol, 4-isopropenylphenol and Phenol. Photogenerated holes, superoxide radical species, ·OH and singlet oxygen were considered to be responsible for the photodegradation process, among which superoxide radical species and ·OH played a predominant role in the photocatalytic reaction system. C 60 modified ZnAlTi-LDO catalysts for photocatalytic reduction shows great potential in degradation of organic pollutants and environmental remediation. - Highlights: • C 60 modified ZnAlTi-LDO enhance the photocatalytic reduction of BPA. • C 60 modified ZnAlTi-LDO was an efficient photocatalytic in the degradation of BPA under visible light. • Superoxide radical species played a predominant role in the photocatalytic reaction system. • C 60 expanded the absorption of ZnAlTi-LDO to visible-light region with the increasing content of C 60 .

  19. New York: Expanding Time, Increasing Opportunities for Achievement

    Science.gov (United States)

    Miller, Tiffany D.

    2014-01-01

    New York is poised to take an important step to improve student achievement by expanding learning time for students attending high-poverty, low-performing schools. Recent district- and state-level investments in expanded learning time--a promising strategy to close achievement and opportunity gaps--will give students more time to learn core…

  20. Innovative isothermal oil-free co-rotating scroll compressor–expander for energy storage with first expander tests

    International Nuclear Information System (INIS)

    Iglesias, A.; Favrat, D.

    2014-01-01

    Highlights: • Doing a new concept of small scale compressed air energy storage. • Presenting a new working process of scroll machinery. • Updating a thermodynamic model of scroll compressor that take into account water injection. • Updating a mathematical model of volumetric loses that take into account sealing effect of liquid water. • Encouraging results to investigate more deeply this new concept. - Abstract: The development of an efficient isothermal turbine and compressor is essential for the realization of a small-scale compressed air energy storage (CAES). This article presents the theoretical development of an oil-free co-rotating scroll air compressor and turbine working with water injection to make the operations of expansion and compression as isothermal as possible. First experimental results in expander mode are shown. The theoretical performance is predicted with the help of a mathematical model using the equations of energy and mass conservation and the equation of state. This model takes into account the effects of water injection and volumetric losses. The experimental prototype is an oil-free scroll air compressor with the distinctive feature of having two mobile involutes working in synchronized co-rotation one relative to another. The prime-mover is an electric motor driving the two scrolls with two synchronizing belts. Water injection in the housing intends to provide a quasi-isothermal compression. The same device is used as an isothermal expander by supplying high-pressure air with water when it rotates backwards in expander mode, the electric motor acting then as a generator. Expected improvements to a standard scroll compressor and expander are a better volumetric efficiency and a greater power density due to a higher rotational speed of the scrolls, thanks to their symmetrical masses. The isothermal processes increase also the overall performance

  1. Energy efficiency analysis of Organic Rankine Cycles with scroll expanders for cogenerative applications

    International Nuclear Information System (INIS)

    Clemente, Stefano; Micheli, Diego; Reini, Mauro; Taccani, Rodolfo

    2012-01-01

    Highlights: ► We present an ORC model composed of a scroll 1D model and a cycle thermodynamic one. ► High-series production components from HVAC field are considered to reduce costs. ► Couplings of the micro-CHP with low-temperature heat sources are analyzed. ► Small and low-cost CHP systems with acceptable electrical efficiency are realizable. ► Higher electrical efficiency are possible modifying the scroll geometry. -- Abstract: Small scale Organic Rankine Cycle (ORC) systems has been the object of a large number of studies in the last decade, because of their suitability for energy recovery and cogenerative applications. The paper presents an ORC numerical model and its applications to two different case studies; the code has been obtained by combining a one-dimensional model of a scroll machine and a thermodynamic model of a whole ORC system. Series production components, such as scroll compressors, from HVAC field, have been first considered in order to reduce costs, because this is a critical issue for small scale energy recovery and cogeneration systems. The detailed model of the scroll machine is capable to calculate the performances of both a compressor and an expander, as function of the geometry of the device and of the working fluid. The model has been first tested and validated by comparing its outputs with experimental tests on a commercial scroll compressor, then used to calculate the working curves of commercial scroll machines originally designed as compressors in the HVAC field, but operating as expanders. The model of the expander has been then integrated in the thermodynamic model of the ORC system. A series of comparisons have been carried out in order to evaluate how the performances are influenced by cycle parameters, scroll geometry and working fluid for different applications. The results confirm the feasibility of small scale CHP systems with acceptable electrical efficiency, taking into account the low-temperature thermal source

  2. ANT: Software for Generating and Evaluating Degenerate Codons for Natural and Expanded Genetic Codes.

    Science.gov (United States)

    Engqvist, Martin K M; Nielsen, Jens

    2015-08-21

    The Ambiguous Nucleotide Tool (ANT) is a desktop application that generates and evaluates degenerate codons. Degenerate codons are used to represent DNA positions that have multiple possible nucleotide alternatives. This is useful for protein engineering and directed evolution, where primers specified with degenerate codons are used as a basis for generating libraries of protein sequences. ANT is intuitive and can be used in a graphical user interface or by interacting with the code through a defined application programming interface. ANT comes with full support for nonstandard, user-defined, or expanded genetic codes (translation tables), which is important because synthetic biology is being applied to an ever widening range of natural and engineered organisms. The Python source code for ANT is freely distributed so that it may be used without restriction, modified, and incorporated in other software or custom data pipelines.

  3. Application of graphene oxide/lanthanum-modified carbon paste electrode for the selective determination of dopamine

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Fengying; Feng, Chenqi; Fu, Ning; Wu, Huihui; Jiang, Jibo, E-mail: jibojiang0506@163.com; Han, Sheng, E-mail: hansheng654321@sina.com

    2015-12-01

    Highlights: • The effective surface area of the modified CPE has been expanded after self-assembly. • The GO–La composite exhibited excellent electrocatalytic activity toward DA. • The GO–La/CPE presented high selectivity, sensitivity, excellent stability and repeatability. - Abstract: A home-made carbon paste electrode (CPE) was reformed by graphene oxide (GO)/lanthanum (La) complexes, and a modified electrode, called GO–La/CPE, was fabricated for the selective determination of dopamine (DA) by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Several factors affecting the electrocatalytic performance of the modified sensor were investigated. Owning to the combination of GO and La ions, the GO–La/CPE sensor exhibited large surface area, well selectivity, good repeatability and stability in the oxidation reaction of DA. At optimal conditions, the response of the GO–La/CPE electrode for determining DA was linear in the region of 0.01–0.1 μM and 0.1–400.0 μM. The limit of detection was down to 0.32 nM (S/N = 3). In addition, this modified electrode was successfully applied to the detection of DA in real urine and serum samples by using standard adding method, showing its promising application in the electroanalysis of real samples.

  4. Expanding the Game Design Space

    DEFF Research Database (Denmark)

    Larsen, Lasse Juel; Majgaard, Gunver

    2016-01-01

    This article considers game design research in educational settings. Its focus is on how undergraduate students – particularly engineering students – learn computer game design. From observations conducted during our game design courses we have developed a model of expanded game design space...... layer establishes correspondence between formal elements of computer games and the structure of problem-based creativity. It addresses how game design challenges should be formulated and how creative solutions can be measured. The fourth and final layer demonstrates how clear framing can act....... It encapsulates the entire development process from the first ideas to the final game with emphasis on game design thinking. Our model of expanded game design space consists of four separate – yet interconnected – layers in the process of game development. The first layer addresses the importance of framing...

  5. Self-expanding/shrinking structures by 4D printing

    Science.gov (United States)

    Bodaghi, M.; Damanpack, A. R.; Liao, W. H.

    2016-10-01

    The aim of this paper is to create adaptive structures capable of self-expanding and self-shrinking by means of four-dimensional printing technology. An actuator unit is designed and fabricated directly by printing fibers of shape memory polymers (SMPs) in flexible beams with different arrangements. Experiments are conducted to determine thermo-mechanical material properties of the fabricated part revealing that the printing process introduced a strong anisotropy into the printed parts. The feasibility of the actuator unit with self-expanding and self-shrinking features is demonstrated experimentally. A phenomenological constitutive model together with analytical closed-form solutions are developed to replicate thermo-mechanical behaviors of SMPs. Governing equations of equilibrium are developed for printed structures based on the non-linear Green-Lagrange strain tensor and solved implementing a finite element method along with an iterative incremental Newton-Raphson scheme. The material-structural model is then applied to digitally design and print SMP adaptive lattices in planar and tubular shapes comprising a periodic arrangement of SMP actuator units that expand and then recover their original shape automatically. Numerical and experimental results reveal that the proposed planar lattice as meta-materials can be employed for plane actuators with self-expanding/shrinking features or as structural switches providing two different dynamic characteristics. It is also shown that the proposed tubular lattice with a self-expanding/shrinking mechanism can serve as tubular stents and grippers for bio-medical or piping applications.

  6. Analysis of a rotating spool expander for Organic Rankine Cycle applications

    Science.gov (United States)

    Krishna, Abhinav

    Increasing interest in recovering or utilizing low-grade heat for power generation has prompted a search for ways in which the power conversion process may be enhanced. Amongst the conversion systems, the Organic Rankine Cycle (ORC) has generated an enormous amount of interest amongst researchers and system designers. Nevertheless, component level technologies need to be developed and match the range of potential applications. In particular, technical challenges associated with scaling expansion machines (turbines) from utility scale to commercial scale have prevented widespread adoption of the technology. In this regard, this work focuses on a novel rotating spool expansion machine at the heart of an Organic Rankine Cycle. A comprehensive, deterministic simulation model of the rotating spool expander is developed. The comprehensive model includes a detailed geometry model of the spool expander and the suction valve mechanism. Sub-models for mass flow, leakage, heat transfer and friction within the expander are also developed. Apart from providing the ability to characterize the expander in a particular system, the model provides a valuable tool to study the impact of various design variables on the performance of the machine. The investigative approach also involved an experimental program to assess the performance of a working prototype. In general, the experimental data showed that the expander performance was sub-par, largely due to the mismatch of prevailing operating conditions and the expander design criteria. Operating challenges during the shakedown tests and subsequent sub-optimal design changes also detracted from performance. Nevertheless, the results of the experimental program were sufficient for a proof-of-concept assessment of the expander and for model validation over a wide range of operating conditions. The results of the validated model reveal several interesting details concerning the expander design and performance. For example, the match

  7. Genetically Modified Food: Knowledge and Attitude of Teachers and Students

    Science.gov (United States)

    Mohapatra, Animesh K.; Priyadarshini, Deepika; Biswas, Antara

    2010-10-01

    The concepts behind the technology of genetic modification of organisms and its applications are complex. A diverse range of opinions, public concern and considerable media interest accompanies the subject. This study explores the knowledge and attitudes of science teachers and senior secondary biology students about the application of a rapidly expanding technology, genetic engineering, to food production. The results indicated significant difference in understanding of concepts related with genetically engineered food stuffs between teachers and students. The most common ideas about genetically modified food were that cross bred plants and genetically modified plants are not same, GM organisms are produced by inserting a foreign gene into a plant or animal and are high yielding. More teachers thought that genetically engineered food stuffs were unsafe for the environment. Both teachers and students showed number of misconceptions, for example, the pesticidal proteins produced by GM organisms have indirect effects through bioaccumulation, induces production of allergic proteins, genetic engineering is production of new genes, GM plants are leaky sieves and that transgenes are more likely to introgress into wild species than mutated species. In general, more students saw benefits while teachers were cautious about the advantages of genetically engineered food stuffs.

  8. Rupture of an expander prosthesis mimics axillary cancer recurrence.

    LENUS (Irish Health Repository)

    Ismael, T

    2005-10-01

    Regional silicone gel migration from a ruptured breast implant has been reported at different locations including the upper extremity, chest wall muscles, axilla and back. We report a patient who presented with an axillary mass that mimicked a regional recurrence 5 years after breast cancer reconstruction with a latissimus dorsi musculocutaneous flap and silicon gel expander-prosthesis. Surgical exploration revealed that the mass contained silicone gel around the port of the breast expander that had ruptured. The mass was confluent with an intracapsular silicone leak through a tract along the tube of the expander port.

  9. Hubble Diagram Test of Expanding and Static Cosmological Models: The Case for a Slowly Expanding Flat Universe

    Directory of Open Access Journals (Sweden)

    Laszlo A. Marosi

    2013-01-01

    Full Text Available We present a new redshift (RS versus photon travel time ( test including 171 supernovae RS data points. We extended the Hubble diagram to a range of z = 0,0141–8.1 in the hope that at high RSs, the fitting of the calculated RS/ diagrams to the observed RS data would, as predicted by different cosmological models, set constraints on alternative cosmological models. The Lambda cold dark matter (ΛCDM, the static universe model, and the case for a slowly expanding flat universe (SEU are considered. We show that on the basis of the Hubble diagram test, the static and the slowly expanding models are favored.

  10. Intermittency Statistics in the Expanding Solar Wind

    Science.gov (United States)

    Cuesta, M. E.; Parashar, T. N.; Matthaeus, W. H.

    2017-12-01

    The solar wind is observed to be turbulent. One of the open questions in solar wind research is how the turbulence evolves as the solar wind expands to great distances. Some studies have focused on evolution of the outer scale but not much has been done to understand how intermittency evolves in the expanding wind beyond 1 AU (see [1,2]). We use magnetic field data from Voyager I spacecraft from 1 to 10AU to study the evolution of statistics of magnetic discontinuities. We perform various statistical tests on these discontinuities and make connections to the physical processes occurring in the expanding wind.[1] Tsurutani, Bruce T., and Edward J. Smith. "Interplanetary discontinuities: Temporal variations and the radial gradient from 1 to 8.5 AU." Journal of Geophysical Research: Space Physics 84.A6 (1979): 2773-2787.[2] Greco, A., et al. "Evidence for nonlinear development of magnetohydrodynamic scale intermittency in the inner heliosphere." The Astrophysical Journal 749.2 (2012): 105.

  11. A novel vortex tube-based N2-expander liquefaction process for enhancing the energy efficiency of natural gas liquefaction

    Directory of Open Access Journals (Sweden)

    Qyyum Muhammad Abdul

    2017-01-01

    Full Text Available This research work unfolds a simple, safe, and environment-friendly energy efficient novel vortex tube-based natural gas liquefaction process (LNG. A vortex tube was introduced to the popular N2-expander liquefaction process to enhance the liquefaction efficiency. The process structure and condition were modified and optimized to take a potential advantage of the vortex tube on the natural gas liquefaction cycle. Two commercial simulators ANSYS® and Aspen HYSYS® were used to investigate the application of vortex tube in the refrigeration cycle of LNG process. The Computational fluid dynamics (CFD model was used to simulate the vortex tube with nitrogen (N2 as a working fluid. Subsequently, the results of the CFD model were embedded in the Aspen HYSYS® to validate the proposed LNG liquefaction process. The proposed natural gas liquefaction process was optimized using the knowledge-based optimization (KBO approach. The overall energy consumption was chosen as an objective function for optimization. The performance of the proposed liquefaction process was compared with the conventional N2-expander liquefaction process. The vortex tube-based LNG process showed a significant improvement of energy efficiency by 20% in comparison with the conventional N2-expander liquefaction process. This high energy efficiency was mainly due to the isentropic expansion of the vortex tube. It turned out that the high energy efficiency of vortex tube-based process is totally dependent on the refrigerant cold fraction, operating conditions as well as refrigerant cycle configurations.

  12. A novel vortex tube-based N2-expander liquefaction process for enhancing the energy efficiency of natural gas liquefaction

    Science.gov (United States)

    Qyyum, Muhammad Abdul; Wei, Feng; Hussain, Arif; Ali, Wahid; Sehee, Oh; Lee, Moonyong

    2017-11-01

    This research work unfolds a simple, safe, and environment-friendly energy efficient novel vortex tube-based natural gas liquefaction process (LNG). A vortex tube was introduced to the popular N2-expander liquefaction process to enhance the liquefaction efficiency. The process structure and condition were modified and optimized to take a potential advantage of the vortex tube on the natural gas liquefaction cycle. Two commercial simulators ANSYS® and Aspen HYSYS® were used to investigate the application of vortex tube in the refrigeration cycle of LNG process. The Computational fluid dynamics (CFD) model was used to simulate the vortex tube with nitrogen (N2) as a working fluid. Subsequently, the results of the CFD model were embedded in the Aspen HYSYS® to validate the proposed LNG liquefaction process. The proposed natural gas liquefaction process was optimized using the knowledge-based optimization (KBO) approach. The overall energy consumption was chosen as an objective function for optimization. The performance of the proposed liquefaction process was compared with the conventional N2-expander liquefaction process. The vortex tube-based LNG process showed a significant improvement of energy efficiency by 20% in comparison with the conventional N2-expander liquefaction process. This high energy efficiency was mainly due to the isentropic expansion of the vortex tube. It turned out that the high energy efficiency of vortex tube-based process is totally dependent on the refrigerant cold fraction, operating conditions as well as refrigerant cycle configurations.

  13. Evaluation of the stiffness characteristics of rapid palatal expander screws

    Directory of Open Access Journals (Sweden)

    Luca Lombardo

    2016-11-01

    Full Text Available Abstract Background The aim of this study is to evaluate the mechanical properties of the screws used for rapid expansion of the upper jaw. Methods Ten types of expansion screw were assessed, seven with four arms: Lancer Philosophy 1, Dentaurum Hyrax Click Medium, Forestadent Anatomic Expander type “S”, Forestadent Anatomic Expander type “S” for narrow palates, Forestadent Memory, Leone A 2620-10 with telescopic guide, and Leone A 0630-10 with orthogonal arms; and three with two arms: Dentaurum Variety S.P., Target Baby REP Veltri, and Leone A 362113. A test expander with the mean dimensions taken from measurements on a sample of 100 expanders was constructed for each screw. The test expanders were connected to the supports of an Instron 4467 (Instron Corp., USA mechanical testing machine equipped with a 500 N load cell, and the compression force exerted after each activation was measured. The mean forces expressed by the two- and four-arm expanders were then compared. Results After five activations, the forces expressed by the two-arm devices were double than those expressed by the four-arm devices on average (224 ± 59.9 N vs. 103 ± 32.9 N, and such values remained high after subsequent activations. Conclusions The expanders tested demonstrated stiffness characteristics compatible with opening of the palatine sutures in pre-adolescent patients. The stiffness of such devices can be further increased during the construction phase.

  14. Esophagorespiratory fistula: treatment with self-expanding covered stent

    International Nuclear Information System (INIS)

    Zang Jian; Dou Yongchong; Wang Zheng; Kong Jian

    2002-01-01

    Objective: To evaluate self-expanding covered stent in the management of esophagorespiratory fistula. Methods: A self-expanding esophageal covered stent was implanted under fluoroscopic guidance in 13 patients with esophagorespiratory fistula. In this series patients aged 31-73 years (60.2 years in average). All patients had a pre-procedure fast of 6-41 days (17.3 days in average), in which 12 patients had pulmonary infection. Results: All fistulas were excluded and swallowing function was restored. No stend-related complication was observed. Pulmonary infection was managed in 10 patients out of 13. The mean survived time was 33.3 wks (1-178 wks) in follow-up. Conclusion: Covered self-expanding stent implantation is a safe and effective treatment of ERF

  15. Uranium enrichment conference on modified contract option, Oak Ridge, Tennessee, July 22, 1975

    International Nuclear Information System (INIS)

    1975-01-01

    The questions and answers presented in this document originated at an industry-wide meeting sponsored by the Energy Research and Development Administration held in Oak Ridge, Tennessee, on July 22, 1975, to discuss features and provisions of an ERDA plan to adjust contracts held by firms receiving uranium enriching services from ERDA. On June 19, 1975, ERDA announced terms of an expanded contract modification plan. The modified contract option broadened a previous plan proposed on January 15, 1975, by the former Atomic Energy Commission. The meeting in Oak Ridge on July 22, 1975, was designed to provide additional information on the expanded contract option and to offer ample opportunity for questions and answers prior to August 18, 1975, by which time enriching services customers who chose the one-time option had to so notify ERDA. The meeting included presentations by officials of ERDA Headquarters and ERDA's Oak Ridge Operations on the features of the contract adjustment offer, including provisions for contract termination in whole, separative work schedule adjustments, and uranium feed delivery schedule relaxation. (auth)

  16. Expanded tenses in the old English orosius a syntactic strengthening*

    Directory of Open Access Journals (Sweden)

    Frančiška Trobevšek Drobnak

    1990-12-01

    Full Text Available The present chapter reports the investigation into certain aspects of the periphrastic construction to be +present participle (e.g. NE: "he is teaching"; OE. "he is laerende" viewed as an example of a syntactic strengthening. The construc­ tion is usually referred to as "continuous tenses/form" or "progressive tenses/form", whereas Nickel (1966 uses "expanded form". Coming closest to this latter term, the "expanded tenses" employed here seems a convenient label for two reasons: a  the use of expanded tenses is not restricted to the expression of verbal aspect (Aspekt or mode of verbal action (Aktionsart, which is implied by the use of either the term "continuous  tenses/form" or the term "progressive tenses/form"; b  the expanded tenses are integrated into the English tense system, in the sense that they can be substituted  with the respective non-expanded tenses without any change in the syntax of the clause, e.g.

  17. Some design features of CO2 swing piston expander

    International Nuclear Information System (INIS)

    Guan Haiqing; Ma Yitai; Li Minxia

    2006-01-01

    CO 2 is a potential substitute for synthesized refrigerants with favorable environmental properties. To improve the coefficient of performance (COP) of CO 2 heat pump systems, a swing piston expander prototype has been developed for replacing the throttling valve based on the thermodynamic analysis of the operating conditions of a CO 2 transcritical cycle. The measures on reducing the loss of friction and leakage are paramount important to improve the efficiency of the expander. The performance of the CO 2 swing expander prototype was actually tested in a CO 2 transcritical cycle water-to-water heat pump test rig, and the test results illustrate that the isentropic efficiency of the prototype can be more than 28% when running steadily and up to a maximum of about 44%. Some operating characteristics of the swing piston expander are presented according to the analysis of the test results

  18. Endovascular therapy of carotid stenosis with self-expandable stent

    International Nuclear Information System (INIS)

    Liu Jianmin; Huang Qinghai; Hong Bo; Xu Yi; Zhao Wenyuan; Zhang Yongwei; Zhang Long; Zhou Xiaoping

    2002-01-01

    Objective: To summarize the experience of endovascular treatment of carotid stenosis with expandable stents. Methods: Fifty-two patients with carotid stenosis who experienced repeated transient ischemic attacks or cerebral infarction were admitted to our hospital. The stenosis was pre-expanded with undetachable balloon, and self-expandable stents were implanted across the stenosis. A balloon catheter was used to further expand stents in 29 patients. Results: The stent was accurately implanted, and total disappearance of stenosis was obtained in 34 patients, the degree of stenosis reduced more than 90% in 16 patients, and more than 70% in 2 patients. The patients recovered well and no complications related to the procedure occurred. None experienced TIA or infarction postoperatively in 52 cases and follow-up imaging in 19 patients (6 - 12 months) demonstrated no restenosis. Conclusion: Endovascular stenting may be a safe and valid choice for the treatment of extracranial carotid stenosis

  19. 49 CFR 173.221 - Polymeric beads, expandable and Plastic molding compound.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Polymeric beads, expandable and Plastic molding... Than Class 1 and Class 7 § 173.221 Polymeric beads, expandable and Plastic molding compound. (a) Non-bulk shipments of Polymeric beads (or granules), expandable, evolving flammable vapor and Plastic...

  20. Operation of an organic Rankine cycle dependent on pumping flow rates and expander torques

    International Nuclear Information System (INIS)

    Yang, Xufei; Xu, Jinliang; Miao, Zheng; Zou, Jinghuang; Yu, Chao

    2015-01-01

    An ORC (organic Rankine cycle) was developed with R123 as the working fluid. The heat capacity is in ∼100 kW. The match between pump and expander is investigated. Lower pump frequencies (f 10 Hz) adapt low expander torques only, and cause unstable flow and pump cavitation for larger expander torques. Ultra-low expander torques generate sufficiently high vapor superheatings to decrease expander efficiencies. Ultra-high expander torques achieve saturation vapor at the expander inlet, causing liquid droplets induced shock wave to worsen expander performance. An optimal range of expander torques exists to have better expander performance. A liquid subcooling of 20 °C is necessary to avoid pump cavitation. Expander powers and efficiencies show parabola shapes versus expander torques, or vapor superheatings at the expander inlet. The optimal vapor superheating is 13 °C. The cavitation mechanisms and measures to avoid cavitation are analyzed. This paper notes the overestimation of ORC performance by equilibrium thermodynamic analysis. Assumptions should be dependent on experiments. Future studies are suggested on organic fluid flow, heat transfer and energy conversion in various components. - Highlights: • The match between pump and expander is investigated. • A liquid subcooling of 20 °C is needed at pump inlet. • A vapor superheating of 13 °C is necessary at expander inlet. • Cavitation in pumps and expanders are analyzed. • The equilibrium thermodynamics overestimate ORC performances.

  1. Development of a novel anisotropic self-inflating tissue expander: in vivo submucoperiosteal performance in the porcine hard palate.

    Science.gov (United States)

    Swan, Marc C; Bucknall, David G; Czernuszka, Jan T; Pigott, David W; Goodacre, Timothy E E

    2012-01-01

    The advent of self-inflating hydrogel tissue expanders heralded a significant advance in the reconstructive potential of this technique. Their use, however, is limited by their uncontrolled isotropic (i.e., uniform in all directions) expansion. Anisotropy (i.e., directional dependence) was achieved by annealing a hydrogel copolymer of poly(methyl methacrylate-co-vinyl pyrrolidone) under a compressive load for a specified time period. The expansion ratio is dictated by the percentage of vinyl pyrrolidone content and the degree of compression. The expansion rate is modified by incorporating the polymer within a silicone membrane. The in vivo efficacy of differing prototype devices was investigated in juvenile pigs under United Kingdom Home Office Licence. The devices were implanted within a submucoperiosteal pocket in a total of six porcine palates; all were euthanized by 6 weeks after implantation. A longitudinal volumetric assessment of the expanded tissue was conducted, in addition to postmortem analysis of the bony and mucoperiosteal palatal elements. Uncoated devices caused excessive soft-tissue expansion that resulted in mucoperiosteal ulceration, thus necessitating animal euthanasia. The silicone-coated devices produced controlled soft-tissue expansion over the 6-week study period. There was a statistically significant increase in the volume of expanded soft tissue with no evidence of a significant acute inflammatory response to the implant, although peri-implant capsule formation was observed. Attenuation of the bony palatal shelf was noted. A unique anisotropic hydrogel device capable of controlled expansion has been developed that addresses a number of the shortcomings of the technology hitherto available.

  2. Cryo-electron Microscopy Structures of Expanded Poliovirus with VHHs Sample the Conformational Repertoire of the Expanded State.

    Science.gov (United States)

    Strauss, Mike; Schotte, Lise; Karunatilaka, Krishanthi S; Filman, David J; Hogle, James M

    2017-02-01

    By using cryo-electron microscopy, expanded 80S-like poliovirus virions (poliovirions) were visualized in complexes with four 80S-specific camelid VHHs (Nanobodies). In all four complexes, the VHHs bind to a site on the top surface of the capsid protein VP3, which is hidden in the native virus. Interestingly, although the four VHHs bind to the same site, the structures of the expanded virus differ in detail in each complex, suggesting that each of the Nanobodies has sampled a range of low-energy structures available to the expanded virion. By stabilizing unique structures of expanded virions, VHH binding permitted a more detailed view of the virus structure than was previously possible, leading to a better understanding of the expansion process that is a critical step in infection. It is now clear which polypeptide chains become disordered and which become rearranged. The higher resolution of these structures also revealed well-ordered conformations for the EF loop of VP2, the GH loop of VP3, and the N-terminal extensions of VP1 and VP2, which, in retrospect, were present in lower-resolution structures but not recognized. These structural observations help to explain preexisting mutational data and provide insights into several other stages of the poliovirus life cycle, including the mechanism of receptor-triggered virus expansion. When poliovirus infects a cell, it undergoes a change in its structure in order to pass RNA through its protein coat, but this altered state is short-lived and thus poorly understood. The structures of poliovirus bound to single-domain antibodies presented here capture the altered virus in what appear to be intermediate states. A careful analysis of these structures lets us better understand the molecular mechanism of infection and how these changes in the virus lead to productive-infection events. Copyright © 2017 American Society for Microbiology.

  3. Tissue Expander Overfilling: Achieving New Dimensions of Customization in Breast Reconstruction.

    Science.gov (United States)

    Treiser, Matthew D; Lahair, Tracy; Carty, Matthew J

    2016-02-01

    Overfill of tissue expanders is a commonly used modality to achieve customized dimensions in breast reconstruction. Little formal study of the dynamics of hyperexpansion of these devices has been performed to date, however. Overfill trials were performed using both Natrelle 133 MV and Mentor 8200 tissue expanders of indicated capacities ranging from 250 to 800 mL. Each expander was initially filled to its indicated capacity with normal water and then injected in regular increments to 400% overfill. Measurements of each expander's width, height, and projection were made at indicated capacity and with each successive incremental overfill injection, and these results were then recorded, collated, and analyzed. Over the first 50% overfill, all expanders demonstrated a logarithmic increase in projection (mean increase, 143 ± 9%) while maintaining essentially stable base dimensions. Overfill levels in excess of 50% were accompanied by linear increases in height, width, and projection, during which projection approached, but never equaled, base dimensions. Stress versus strain analyses demonstrated nonlinear biomechanical dynamics during the first 50% overfill, followed by standard elastic dynamics up to 400% overfill. At no point during the study, did expander tensions outstrip elastic properties, thereby explaining the lack of device rupture. Through overfilling, tunable geometries of tissue expanders can be accessed that may provide for increasing customization of reconstructions, particularly at overfill volumes up to 50% over indicated capacity. This study should serve to guide tissue expander selection and fill volumes that surgeons may implement in obtaining ideal reconstructed breast shapes.

  4. Flexural Behaviour Of Reinforced Concrete Beams Containing Expanded Glass As Lightweight Aggregates

    Directory of Open Access Journals (Sweden)

    Khatib Jamal

    2015-12-01

    Full Text Available The flexural properties of reinforced concrete beams containing expanded glass as a partial fine aggregate (sand replacement are investigated. Four concrete mixes were employed to conduct this study. The fine aggregate was replaced with 0%, 25%, 50% and 100% (by volume expanded glass. The results suggest that the incorporation of 50% expanded glass increased the workability of the concrete. The compressive strength was decreasing linearly with the increasing amount of expanded glass. The ductility of the concrete beam significantly improved with the incorporation of the expanded glass. However, the load-carrying capacity of the beam and load at which the first crack occurs was reduced. It was concluded that the inclusion of expanded glass in structural concrete applications is feasible.

  5. Theoretical models for recombination in expanding gas

    International Nuclear Information System (INIS)

    Avron, Y.; Kahane, S.

    1978-09-01

    In laser isotope separation of atomic uranium, one is confronted with the theoretical problem of estimating the concentration of thermally ionized uranium atoms. To investigate this problem theoretical models for recombination in an expanding gas and in the absence of local thermal equilibrium have been constructed. The expansion of the gas is described by soluble models of the hydrodynamic equation, and the recombination by rate equations. General results for the freezing effect for the suitable ranges of the gas parameters are obtained. The impossibility of thermal equilibrium in expanding two-component systems is proven

  6. Growth promotion of genetically modified hematopoietic progenitors using an antibody/c-Mpl chimera.

    Science.gov (United States)

    Kawahara, Masahiro; Chen, Jianhong; Sogo, Takahiro; Teng, Jinying; Otsu, Makoto; Onodera, Masafumi; Nakauchi, Hiromitsu; Ueda, Hiroshi; Nagamune, Teruyuki

    2011-09-01

    Thrombopoietin is a potent cytokine that exerts proliferation of hematopoietic stem cells (HSCs) through its cognate receptor, c-Mpl. Therefore, mimicry of c-Mpl signaling by a receptor recognizing an artificial ligand would be attractive to attain specific expansion of genetically modified HSCs. Here we propose a system enabling selective expansion of genetically modified cells using an antibody/receptor chimera that can be activated by a specific antigen. We constructed an antibody/c-Mpl chimera, in which single-chain Fv (ScFv) of an anti-fluorescein antibody was tethered to the extracellular D2 domain of the erythropoietin receptor and transmembrane/cytoplasmic domains of c-Mpl. When the chimera was expressed in interleukin (IL)-3-dependent pro-B cell line Ba/F3, genetically modified cells were selectively expanded in the presence of fluorescein-conjugated BSA (BSA-FL) as a specific antigen. Furthermore, highly purified mouse HSCs transduced with the retrovirus carrying antibody/c-Mpl chimera gene proliferated in vitro in response to BSA-FL, and the cells retained in vivo long-term repopulating abilities. These results demonstrate that the antibody/c-Mpl chimera is capable of signal transduction that mimics wild-type c-Mpl signaling. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Equilibrium thermodynamics in modified gravitational theories

    International Nuclear Information System (INIS)

    Bamba, Kazuharu; Geng, C.-Q.; Tsujikawa, Shinji

    2010-01-01

    We show that it is possible to obtain a picture of equilibrium thermodynamics on the apparent horizon in the expanding cosmological background for a wide class of modified gravity theories with the Lagrangian density f(R,φ,X), where R is the Ricci scalar and X is the kinetic energy of a scalar field φ. This comes from a suitable definition of an energy-momentum tensor of the 'dark' component that respects to a local energy conservation in the Jordan frame. In this framework the horizon entropy S corresponding to equilibrium thermodynamics is equal to a quarter of the horizon area A in units of gravitational constant G, as in Einstein gravity. For a flat cosmological background with a decreasing Hubble parameter, S globally increases with time, as it happens for viable f(R) inflation and dark energy models. We also show that the equilibrium description in terms of the horizon entropy S is convenient because it takes into account the contribution of both the horizon entropy S in non-equilibrium thermodynamics and an entropy production term.

  8. Differences in Endothelial Injury After Balloon Angioplasty, Insertion of Balloon-Expanded Stents or Release of Self-Expanding Stents: An Electron Microscopic Experimental Study

    International Nuclear Information System (INIS)

    Harnek, Jan; Zoucas, Evita; Carlemalm, Erik; Cwikiel, Wojciech

    1999-01-01

    Purpose: To evaluate which of six different commonly available stents inserted into an artery without percutaneous transluminal angioplasty (PTA) causes the least endothelial damage. To compare the degree of endothelial injury after insertion of such a stent with injury caused by PTA. Methods: Twelve healthy pigs were used in the experiments. In the first part of the study six different types of stents were inserted into the common iliac arteries. In the second part of the study self-expanding stents with large spaces between the wires were used. PTA was performed in the contralateral iliac artery. The pigs were killed immediately after the procedure and resected specimens examined after fixation, using scanning electron microscopy. Results: All procedures but two were accomplished successfully. More endothelium was preserved after insertion of self-expanding stents with large spaces between the wires, compared with stents with small spaces and balloon-expanded stents. After insertion of self-expanding stents with large spaces, 50.1% ± 16.4% of the endothelium remained intact, compared with only 5.6% ± 7.7% after PTA. The difference was statistically significant (p < 0.001). Conclusion: Self-expanding stents with large spaces between the wires, inserted without PTA, cause less damage to the endothelium than other stents and significantly less damage than PTA

  9. Study on paraffin/expanded graphite composite phase change thermal energy storage material

    International Nuclear Information System (INIS)

    Zhang Zhengguo; Fang Xiaoming

    2006-01-01

    A paraffin/expanded graphite composite phase change thermal energy storage material was prepared by absorbing the paraffin into an expanded graphite that has an excellent absorbability. In such a composite, the paraffin serves as a latent heat storage material and the expanded graphite acts as the supporting material, which prevents leakage of the melted paraffin from its porous structure due to the capillary and surface tension forces. The inherent structure of the expanded graphite did not change in the composite material. The solid-liquid phase change temperature of the composite PCM was the same as that of the paraffin, and the latent heat of the paraffin/expanded graphite composite material was equivalent to the calculated value based on the mass ratio of the paraffin in the composite. The heat transfer rate of the paraffin/expanded graphite composite was obviously higher than that of the paraffin due to the combination with the expanded graphite that had a high thermal conductivity. The prepared paraffin/expanded graphite composite phase change material had a large thermal storage capacity and improved thermal conductivity and did not experience liquid leakage during its solid-liquid phase change

  10. Expanded function allied dental personnel and dental practice productivity and efficiency.

    Science.gov (United States)

    Beazoglou, Tryfon J; Chen, Lei; Lazar, Vickie F; Brown, L Jackson; Ray, Subhash C; Heffley, Dennis R; Berg, Rob; Bailit, Howard L

    2012-08-01

    This study examined the impact of expanded function allied dental personnel on the productivity and efficiency of general dental practices. Detailed practice financial and clinical data were obtained from a convenience sample of 154 general dental practices in Colorado. In this state, expanded function dental assistants can provide a wide range of reversible dental services/procedures, and dental hygienists can give local anesthesia. The survey identified practices that currently use expanded function allied dental personnel and the specific services/procedures delegated. Practice productivity was measured using patient visits, gross billings, and net income. Practice efficiency was assessed using a multivariate linear program, Data Envelopment Analysis. Sixty-four percent of the practices were found to use expanded function allied dental personnel, and on average they delegated 31.4 percent of delegatable services/procedures. Practices that used expanded function allied dental personnel treated more patients and had higher gross billings and net incomes than those practices that did not; the more services they delegated, the higher was the practice's productivity and efficiency. The effective use of expanded function allied dental personnel has the potential to substantially expand the capacity of general dental practices to treat more patients and to generate higher incomes for dental practices.

  11. The use of thermally expandable microcapsules for increasing the toughness and heal structural adhesives

    Directory of Open Access Journals (Sweden)

    Chiaki Sato

    2011-04-01

    Full Text Available In this research, the effect of thermally expandable microcapsules (TEMs on mode I fracture toughness of structural adhesives were investigated. The single-edge-notch bending (SENB test was used. Firstly, a standard toughness test was performed on adhesives with microcapsules. Secondly, since TEMs start their expansion at approximately 60ºC, the next specimens were fatigue tested expecting a local heating in the notch leading to the desired expansion before being statically loaded for fracture toughness determination. Thirdly, a manual local heating at 90ºC was applied in the notch before the fracture static test. The experimental results were successfully cross-checked through a numerical analysis using the virtual crack closure technique (VCCT based on linear elastic fracture mechanics (LEFM. The major conclusion is that fracture toughness of the modified adhesives increased as the mass fraction of the TEMs increased.

  12. Correct integration of compressors and expanders in above ambient heat exchanger networks

    International Nuclear Information System (INIS)

    Fu, Chao; Gundersen, Truls

    2016-01-01

    The Appropriate Placement concept (also referred to as Correct Integration) is fundamental in Pinch Analysis. The placement of reactors, distillation columns, evaporators, heat pumps and heat engines in heat exchanger networks is well established. The placement of pressure changing equipment such as compressors and expanders is complex and less discussed in literature. A major difficulty is that both heat and work (not only heat) are involved. The integration of compressors and expanders separately into heat exchanger networks was recently investigated. A set of theorems were proposed for assisting the design. The problem is even more complex when both compressors and expanders are to be integrated. An important concern is about the sequence of integration with compressors and expanders, i.e. should compressors or expanders be implemented first. This problem is studied and a new theorem is formulated related to the Correct Integration of both compressors and expanders in above ambient heat exchanger networks. The objective is to minimize exergy consumption for the integrated processes. A graphical design methodology is developed for the integration of compressors and expanders into heat exchanger networks above ambient temperature. - Highlights: • The correct integration of compressors and expanders in heat exchanger networks is studied. • A theorem is proposed for heat integration between compressors and expanders. • The total exergy consumption is minimized.

  13. Environmental assessment, expanded Ponnequin wind energy project, Weld County, Colorado

    International Nuclear Information System (INIS)

    1999-02-01

    The US Department of Energy (DOE) has considered a proposal from the State of Colorado, Office of Energy Conservation (OEC), for funding construction of the Expanded Ponnequin Wind Project in Weld County, Colorado. OEC plans to enter into a contracting arrangement with Public Service Company of Colorado (PSCo) for the completion of these activities. PSCo, along with its subcontractors and business partners, are jointly developing the Expanded Ponnequin Wind Project. The purpose of this Final Environmental Assessment (EA) is to provide DOE and the public with information on potential environmental impacts associated with the Expanded Ponnequin Wind Energy Project. This EA, and public comments received on it, were used in DOE's deliberations on whether to release funding for the expanded project under the Commercialization Ventures Program

  14. Environmental assessment, expanded Ponnequin wind energy project, Weld County, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-02-01

    The US Department of Energy (DOE) has considered a proposal from the State of Colorado, Office of Energy Conservation (OEC), for funding construction of the Expanded Ponnequin Wind Project in Weld County, Colorado. OEC plans to enter into a contracting arrangement with Public Service Company of Colorado (PSCo) for the completion of these activities. PSCo, along with its subcontractors and business partners, are jointly developing the Expanded Ponnequin Wind Project. The purpose of this Final Environmental Assessment (EA) is to provide DOE and the public with information on potential environmental impacts associated with the Expanded Ponnequin Wind Energy Project. This EA, and public comments received on it, were used in DOE`s deliberations on whether to release funding for the expanded project under the Commercialization Ventures Program.

  15. Self-Expanding, Tough Biodegradable Elastomers for Wound Stasis

    Science.gov (United States)

    2015-08-06

    the civilian setting, with no effective therapies available at point of injury. We previously reported that a self- expanding polyurethane foam...setting, with no effective therapies available at point of injury. We previously reported that a self-expanding polyurethane foam significantly...care in accor- dance with the Guide of the Care and Use of Laboratory Ani- mals (Health, 2011 #17). 2.2. Instrumentation and monitoring All swine (n

  16. EFFECT OF INCORPORATING EXPANDED POLYSTYRENE ...

    African Journals Online (AJOL)

    2012-11-03

    Nov 3, 2012 ... Incorporating expanded polystyrene granules in concrete matrix can produce lightweight polystyrene aggregate concrete of ... structure. [1] reported that the standard workability tests are not suitable for the polystyrene aggregate concrete since they are sensitive to the unit weight of concrete. [2] made ...

  17. Expanding Greenland’s Glacial Record

    DEFF Research Database (Denmark)

    Bjørk, Anders Anker

    . On order to expand the glacial history of Greenland, this thesis explores physical and geological archives for evidence of the glaciers’ past response to climatic variations. Using aerial photographs, the dynamic history of the Greenland Ice Sheet is extended back to 1900 C.E. Glacier changes covering...

  18. Expandable Total Humeral Replacement in a Child with Osteosarcoma

    Directory of Open Access Journals (Sweden)

    Eric R. Henderson

    2015-01-01

    Full Text Available Case. A right-handed 8-year-old female patient presented with a conventional, high-grade osteosarcoma involving her right humerus; through-shoulder amputation was recommended. After consultation, total humerus resection with expandable, total humeral endoprosthesis reconstruction was performed with a sleeve to encourage soft-tissue ingrowth. At three-year follow-up she has received one lengthening procedure and her functional scores are excellent. Conclusion. Total humeral resection and replacement in the pediatric population are rare and although early reports of expandable total humeral endoprosthesis outcomes demonstrate high failure rates, this patient’s success indicates that expandable total humeral replacement is a viable option.

  19. Principles of the fifth order tuning of beam expanders

    International Nuclear Information System (INIS)

    Meot, F.; Aniel, T.

    1995-01-01

    An analytical treatment of the third and fifth order optics of beam expanders is described, which allows precise tuning of the optical elements of the beam line, and efficient optimization of the beam uniformizing at the extended target. An application to a two-dimensional expander is given as an illustration. (authors)

  20. Modifiable risk factors for prescription medicine sharing behaviours.

    Science.gov (United States)

    Beyene, Kebede; Aspden, Trudi; McNeill, Rob; Sheridan, Janie

    2018-04-06

    Prescription medicine sharing has been defined as giving one's own medicine to someone else (lending) or taking someone else's medicine (borrowing). Medicines can be shared for non-medical purposes (recreational sharing or drug abuse) or for their intended therapeutic benefits (non-recreational sharing, e.g. sharing antibiotics to self-treat); the latter is the focus of this research. Limited research evidence is available about modifiable risk factors for non-recreational medicine sharing and addressing this issue was the main aim of this research. An online, cross-sectional survey design was used. The study population comprised a convenience sample of 233 adults, who were primarily recruited through patient support groups across New Zealand. Principal component analysis was used to develop scales assessing attitudes toward medicine lending and borrowing. Logistic regression was used to examine the relationship between explanatory (demographics, medical conditions, and attitudes towards medicine sharing) and outcome (medicine sharing behaviours) variables. Half of the study participants reported ever borrowing/lending medicines, and approximately a third of participants reported borrowing/lending in the past year. Modifiable risk factors associated with an increased risk of medicine borrowing behaviour were having more difficulty with accessing medicine ('access-related issue'), stronger 'emotional beliefs about borrowing', and greater 'concern about missing doses.' Greater 'concern for the wellbeing of others' and stronger 'beliefs about the benefits and safety of lending' were associated with an increased risk of medicine lending behaviour. Those with a higher 'perceived risk of harm' were less likely to borrow or lend medicines. This research expands the current knowledge of medicine sharing by examining underlying behavioural factors which predict sharing behaviours and that can be modified by interventions. This research suggests using multifaceted

  1. Theoretical investigation of flash vaporisation in a screw expander

    Science.gov (United States)

    Vasuthevan, Hanushan; Brümmer, Andreas

    2017-08-01

    In the present study flash vaporisation of liquid injection in a twin screw expander for a Trilateral Flash Cycle (TFC) is examined theoretically. The TFC process comprises a pressure increase in the working fluid, followed by heating the liquid close to boiling point. The hot liquid is injected into the working chamber of a screw expander. During this process the pressure of the liquid drops below the saturation pressure, while the temperature of the liquid remains virtually constant. Hence the liquid is superheated and in a metastable state. The liquid jet seeks to achieve a stable state in thermodynamic equilibrium and is therefore partially vaporised. This effect is referred to as flash vaporisation. Accordingly, a two-phase mixture, consisting of vapour and liquid, exists in the working chamber. Thermodynamic simulations were carried out using water as the working fluid for representative screw expander geometry. The simulations presented are performed from two different aspects during the filling process of a screw expander. The first case is the vaporisation of the injected liquid in a state of thermodynamic equilibrium, whereby the two-phase mixture is treated entirely as a compressible and homogeneous gas. The second case considers flashing efficiency. It describes the quantity of flashed vapour and consists of a liquid and vapour domain. Both models are compared and analysed with respect to the operational behaviour of a screw expander.

  2. Expanding the HAWC Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Johanna [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-17

    The High Altitude Water Cherenkov Gamma-Ray Observatory is expanding its current array of 300 water tanks to include 350 outrigger tanks to increase sensitivity to gamma rays above 10 TeV. This involves creating and testing hardware with which to build the new tanks, including photomultiplier tubes, high voltage supply units, and flash analog to digital converters. My responsibilities this summer included preparing, testing and calibrating that equipment.

  3. Expanding the Universe of Education.

    Science.gov (United States)

    Parsons, Elizabeth

    1996-01-01

    Definitions of "education" and "rural" are debunked and expanded. The three major tasks of rural education are educating people to understand their own needs, the unavoidable changes that will transform rural Australia within their lifetimes, and the range of technologies that can enhance their well-being. Presents a strategy…

  4. Can microcarrier-expanded chondrocytes synthesize cartilaginous tissue in vitro?

    Science.gov (United States)

    Surrao, Denver C; Khan, Aasma A; McGregor, Aaron J; Amsden, Brian G; Waldman, Stephen D

    2011-08-01

    Tissue engineering is a promising approach for articular cartilage repair; however, it is challenging to produce adequate amounts of tissue in vitro from the limited number of cells that can be extracted from an individual. Relatively few cell expansion methods exist without the problems of de-differentiation and/or loss of potency. Recently, however, several studies have noted the benefits of three-dimensional (3D) over monolayer expansion, but the ability of 3D expanded chondrocytes to synthesize cartilaginous tissue constructs has not been demonstrated. Thus, the purpose of this study was to compare the properties of engineered cartilage constructs from expanded cells (monolayer and 3D microcarriers) to those developed from primary chondrocytes. Isolated bovine chondrocytes were grown for 3 weeks in either monolayer (T-Flasks) or 3D microcarrier (Cytodex 3) expansion culture. Expanded and isolated primary cells were then seeded in high density culture on Millicell™ filters for 4 weeks to evaluate the ability to synthesize cartilaginous tissue. While microcarrier expansion was twice as effective as monolayer expansion (microcarrier: 110-fold increase, monolayer: 52-fold increase), the expanded cells (monolayer and 3D microcarrier) were not effectively able to synthesize cartilaginous tissue in vitro. Tissues developed from primary cells were substantially thicker and accumulated significantly more extracellular matrix (proteoglycan content: 156%-292% increase; collagen content: 70%-191% increase). These results were attributed to phenotypic changes experienced during the expansion phase. Monolayer expanded chondrocytes lost their native morphology within 1 week, whereas microcarrier-expanded cells were spreading by 3 weeks of expansion. While the use of 3D microcarriers can lead to large cellular yields, preservation of chondrogenic phenotype during expansion is required in order to synthesize cartilaginous tissue.

  5. Tissue engineering of bladder using vascular endothelial growth factor gene-modified endothelial progenitor cells.

    Science.gov (United States)

    Chen, Bai-Song; Xie, Hua; Zhang, Sheng-Li; Geng, Hong-Quan; Zhou, Jun-Mei; Pan, Jun; Chen, Fang

    2011-12-01

    This study assessed the use of vascular endothelial growth factor (VEGF) gene-modified endothelial progenitor cells (EPCs) seeded onto bladder acellular matrix grafts (BAMGs), to enhance the blood supply in tissue-engineered bladders in a porcine model. Autologous porcine peripheral EPCs were isolated, cultured, expanded, characterized, and modified with the VEGF gene using an adenovirus vector. The expression of VEGF was examined using reverse transcriptase polymerase chain reaction (RT-PCR) and an enzyme-linked immunosorbent assay (ELISA). VEGF gene modified EPCs were seeded onto BAMG and cultured for 3 days before implantation into pigs for bladder tissue engineering. A partial bladder cystectomy was performed in 12 pigs. The experimental group (6 pigs) received VEGF gene-modified EPC-seeded BAMG. The control group (6 pigs) received BAMG without seeded EPCs. The resulting tissue-engineered bladders were subject to a general and histological analysis. Microvessel density (MVD) was assessed using immunohistochemistry. The ex vivo transfection efficiency of EPCs was greater than 60%-70% when concentrated adenovirus was used. The genetically modified cells expressed both VEGF and green fluorescent protein (GFP). Scanning electron microscopy (SEM) and Masson's trichrome staining of cross sections of the cultured cells seeded to BAMG showed cell attachment and proliferation on the surface of the BAMG. Histological examination revealed bladder regeneration in a time-dependent fashion. Significant increases in MVD were observed in the experimental group, in comparison with the control group. VEGF-modified EPCs significantly enhanced neovascularization, compared with BAMG alone. These results indicate that EPCs, combined with VEGF gene therapy, may be a suitable approach for increasing blood supply in the tissue engineering of bladders. Thus, a useful strategy to achieve a tissue-engineered bladder is indicated.

  6. Optimization of Extrusion Process of Directly Expanded Snacks Based on Potato Starch in a Single Step for the Formation of Type IV Resistant Starch.

    Science.gov (United States)

    Calvo-López, Amira Daniela; Martínez-Bustos, Fernando

    2017-09-01

    Resistant starch type IV (RSIV) can be produced by chemical modifications (etherized or esterified) such as conversion, substitution, or cross-linking, which can prevent its digestion by blocking enzyme access and forming atypical linkages. In this research, the effects of barrel temperature (145.86-174.14 °C), the screw speed (42.93-57.07 Hz) and derivatization (esterification) in the formation of RSIV content of directly expanded snacks (second generation snacks) were studied. Potato starch was chemically modified by phosphorylation and succinylation, and expanded by using the extrusion cooking process. Snacks with phosphorylated starch showed expansion index from 2.57 to 3.23, bulk density from 306.19 to 479.00 kg/m 3 and RSIV from 43.27 to 55.81%. Snacks with succinylated starch had expansion index from 3.52 to 3.82, bulk density from 99.85 to 134.51 kg/m 3 and RSIV from 23.17 to 35.01%. The results found in this work showed that it is possible to manufacture extruded directly expanded snacks (second-generation snacks) such as a ready-to-eat (RTE) with good physicochemical properties and without substantial loss of extrusion functionality, which could bring a healthy benefit due to the presence of RSIV.

  7. The expanding universe

    CERN Document Server

    Lew, Kristi

    2011-01-01

    People have always been fascinated with the stars above and the universe that contains them. Over the years, astronomers have developed numerous theories to explain how the universe began, how it works, and what its ultimate fate will be. But all of the scientists' questions are far from answered. The Expanding Universe goes beyond the creation of the universe to explain how scientists think the universe works, grows, and changes, including what great thinkers Isaac Newton and Albert Einstein had to say about its fate. Readers will also learn about how researchers are slowly shedding light on

  8. Modified cyanobacteria

    Science.gov (United States)

    Vermaas, Willem F J.

    2014-06-17

    Disclosed is a modified photoautotrophic bacterium comprising genes of interest that are modified in terms of their expression and/or coding region sequence, wherein modification of the genes of interest increases production of a desired product in the bacterium relative to the amount of the desired product production in a photoautotrophic bacterium that is not modified with respect to the genes of interest.

  9. Ecological and evolutionary processes at expanding range margins

    OpenAIRE

    Thomas, C.D.; Bodsworth, E.J.; Wilson, R.J.; Simmons, A.D.; Davies, Z.G.; Musche, M.; Conradt, L.

    2001-01-01

    Many animals are regarded as relatively sedentary and specialized in marginal parts of their geographical distributions. They are expected to be slow at colonizing new habitats. Despite this, the cool margins of many species' distributions have expanded\\ud rapidly in association with recent climate warming3±10. We examined four insect species that have expanded their geographical\\ud ranges in Britain over the past 20 years. Here we report that two butterfly species have increased the variety ...

  10. Black holes in an expanding universe.

    Science.gov (United States)

    Gibbons, Gary W; Maeda, Kei-ichi

    2010-04-02

    An exact solution representing black holes in an expanding universe is found. The black holes are maximally charged and the universe is expanding with arbitrary equation of state (P = w rho with -1 < or = for all w < or = 1). It is an exact solution of the Einstein-scalar-Maxwell system, in which we have two Maxwell-type U(1) fields coupled to the scalar field. The potential of the scalar field is an exponential. We find a regular horizon, which depends on one parameter [the ratio of the energy density of U(1) fields to that of the scalar field]. The horizon is static because of the balance on the horizon between gravitational attractive force and U(1) repulsive force acting on the scalar field. We also calculate the black hole temperature.

  11. Parameter estimation for an expanding universe

    Directory of Open Access Journals (Sweden)

    Jieci Wang

    2015-03-01

    Full Text Available We study the parameter estimation for excitations of Dirac fields in the expanding Robertson–Walker universe. We employ quantum metrology techniques to demonstrate the possibility for high precision estimation for the volume rate of the expanding universe. We show that the optimal precision of the estimation depends sensitively on the dimensionless mass m˜ and dimensionless momentum k˜ of the Dirac particles. The optimal precision for the ratio estimation peaks at some finite dimensionless mass m˜ and momentum k˜. We find that the precision of the estimation can be improved by choosing the probe state as an eigenvector of the hamiltonian. This occurs because the largest quantum Fisher information is obtained by performing projective measurements implemented by the projectors onto the eigenvectors of specific probe states.

  12. Therapeutic embolization in pulmonary hemorrhage

    International Nuclear Information System (INIS)

    Gasparini, D.

    1989-01-01

    The author's purpose was to evaluate the efficacy of therapeutic embolization in pulmonary hemorrage performed with fibrin foam (Spongostan) suspended in sclerosing agents (hidroxy-poliethoxy-dodecano 3%, or natrium morruate 5%), and electrocoagulation (Bitrol, spa) as an alternative to surgery. Twenty patients were embolized: 17 with fibrin foam and sclerosing agents only, 2 with the addition of electrocoagulation and a Gianturco coil respectively, and 1 with electrocoagulation alone. The follow-up ranges from 3 to 42 months (average 22). A patient affected by aspergilloma died a few days after hemoptysis. The patient treated by electrocoagulation alone suffers from periodical hematic expectoration (spitting). The remaining 18 patients have not shown any pathological findings. In 2 cases the arterial occlusion was confirmed by angiography, while in 1 case partial arterial recanalization was observed. Such a finding was due to the vessel dimensions and to hyperflux values. In similar cases, obstruction must be completed different techniques (e.g. Gianturco coils, electrocoagulation, detachable balloons, etc.). The absence of flux resulting from embolization improves electrocoagulation efficiency, which should be considered as the technique of choice. Even though additional trials are needed, the techniques have proven quite reliable and suitable to replace surgery in low-aggression lesions

  13. Role of expanders in helium liquefaction cycles: Parametric studies using Collins cycle

    International Nuclear Information System (INIS)

    Thomas, Rijo Jacob; Ghosh, Parthasarathi; Chowdhury, Kanchan

    2011-01-01

    Large scale helium liquefaction/refrigeration plant is a key subsystem of fusion devices. Performance of these plants is dependent on a number of geometric and operating parameters of its constituting components such as compressors, heat exchangers, expanders, valves, etc. Expander has been chosen as the subject matter of analyses in the present study. As the sensible cold of helium vapor is lost in liquefiers, the expanders in liquefaction cycles have to provide more refrigeration than those in refrigeration cycles. The expander parameters such as rate of mass flow, operating pressure, inlet temperature, etc. are inter-dependent, and hence, it is difficult to predict the system behavior with variation of a particular parameter. This necessitates the use of process simulators. Parametric studies have been performed on Collins helium liquefaction cycle using Aspen HYSYS. Collins cycle has all the basic characteristics of a large-scale helium liquefier and the results of this study may be extrapolated to understand the behavior of large scale helium liquefiers. The study shows that the maximum liquid production is obtained when 80% of the compressor flow is diverted through the expanders and it is equally distributed between the two expanders. The relationships between the liquid production and the isentropic efficiency of expanders are almost linear and both the higher and lower temperature expanders exhibit similar trends.

  14. Role of expanders in helium liquefaction cycles: Parametric studies using Collins cycle

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Rijo Jacob, E-mail: rijojthomas@gmail.com [Cryogenic Engineering Centre, Indian Institute of Technology, Kharagpur, West Bengal 721302 (India); Ghosh, Parthasarathi; Chowdhury, Kanchan [Cryogenic Engineering Centre, Indian Institute of Technology, Kharagpur, West Bengal 721302 (India)

    2011-06-15

    Large scale helium liquefaction/refrigeration plant is a key subsystem of fusion devices. Performance of these plants is dependent on a number of geometric and operating parameters of its constituting components such as compressors, heat exchangers, expanders, valves, etc. Expander has been chosen as the subject matter of analyses in the present study. As the sensible cold of helium vapor is lost in liquefiers, the expanders in liquefaction cycles have to provide more refrigeration than those in refrigeration cycles. The expander parameters such as rate of mass flow, operating pressure, inlet temperature, etc. are inter-dependent, and hence, it is difficult to predict the system behavior with variation of a particular parameter. This necessitates the use of process simulators. Parametric studies have been performed on Collins helium liquefaction cycle using Aspen HYSYS. Collins cycle has all the basic characteristics of a large-scale helium liquefier and the results of this study may be extrapolated to understand the behavior of large scale helium liquefiers. The study shows that the maximum liquid production is obtained when 80% of the compressor flow is diverted through the expanders and it is equally distributed between the two expanders. The relationships between the liquid production and the isentropic efficiency of expanders are almost linear and both the higher and lower temperature expanders exhibit similar trends.

  15. Biodegradation of high strength phenolic wastewater in a modified external loop inversed fluidized bed airlift bioreactor (EIFBAB)

    Energy Technology Data Exchange (ETDEWEB)

    Aye, T. T.; Loh, K-C. [National University of Singapore, Dept. of Chemical and Environmental Engineering, (Singapore)

    2003-12-01

    Phenol degradation at high concentrations was investigated in both batch and continuous mode, using a modified external loop inversed fluidized bed airlift bioreactor (EIFBAB). It was found that the modified EIFBAB, when operated at five litres/hour was capable of degrading 3,000 mg/L phenol. Under continuous operation the bioreactor was capable of degrading up to 5,000 mg/L phenol, with gradual acclimatization of the biofilm on the expanded polystyrene beads. Response of the system under shock loading was also evaluated. Results showed that the system was able to absorb the shock well up to 5,000 mg/L phenol. Although phenol breakthrough was evident in the effluent beyond 4,500 mg/L., the increase in effluent phenol concentration was gradual, and the effluent concentration did not increase beyond 1,000 mg/L phenol. 6 refs., 3 tabs., 3 figs.

  16. Coupled-expanding maps and one-sided symbolic dynamical systems

    International Nuclear Information System (INIS)

    Shi Yuming; Ju, Hyonhui; Chen Guanrong

    2009-01-01

    This paper studies relationships between coupled-expanding maps and one-sided symbolic dynamical systems. The concept of coupled-expanding map is extended to a more general one: coupled-expansion for a transitive matrix. It is found that the subshift for a transitive matrix is strictly coupled-expanding for the matrix in certain disjoint compact subsets; the topological conjugacy of a continuous map in its compact invariant set of a metric space to a subshift for a transitive matrix has a close relationship with that the map is strictly coupled-expanding for the matrix in some disjoint compact subsets. A certain relationship between strictly coupled-expanding maps for a transitive matrix in disjoint bounded and closed subsets of a complete metric space and their topological conjugacy to the subshift for the matrix is also obtained. Dynamical behaviors of subshifts for irreducible matrices are then studied and several equivalent statements to chaos are obtained; especially, chaos in the sense of Li-Yorke is equivalent to chaos in the sense of Devaney for the subshift, and is also equivalent to that the domain of the subshift is infinite. Based on these results, several new criteria of chaos for maps are finally established via strict coupled-expansions for irreducible transitive matrices in compact subsets of metric spaces and in bounded and closed subsets of complete metric spaces, respectively, where their conditions are weaker than those existing in the literature.

  17. Adsorption of arsenic(III) into modified lamellar Na-magadiite in aqueous medium—Thermodynamic of adsorption process

    Science.gov (United States)

    Guerra, Denis Lima; Pinto, Alane Azevedo; Airoldi, Claudio; Viana, Rúbia Ribeiro

    2008-12-01

    Synthetic Na-magadiite sample was used for organofunctionalization process with N-propyldiethylenetrimethoxysilane and bis[3-(triethoxysilyl)propyl]tetrasulfide, after expanding the interlayer distance with polar organic solvents such as dimethylsulfoxide (DMSO). The resulted materials were submitted to process of adsorption with arsenic solution at pH 2.0 and 298±1 K. The adsorption isotherms were adjusted using a modified Langmuir equation with regression nonlinear; the net thermal effects obtained from calorimetric titration measurements were adjusted to a modified Langmuir equation. The adsorption process was exothermic (Δ intH=-4.15-5.98 kJ mol -1) accompanied by increase in entropy (Δ intS=41.32-62.20 J k -1 mol -1) and Gibbs energy (Δ intG=-22.44-24.56 kJ mol -1). The favorable values corroborate with the arsenic (III)/basic reactive centers interaction at the solid-liquid interface in the spontaneous process.

  18. Expanded-boundary approach to impurity control in tokamaks

    International Nuclear Information System (INIS)

    Ohyabu, N.

    1981-01-01

    It is proposed to expand the outermost flux surfaces in tokamaks to divert the heat flux emerging from the plasma core. The expanded flux surfaces provide a large volume for radiative cooling. The radiative power at the boundary is enhanced by the effects of plasma flow as well as by a volumetric factor, and the resultant edge cooling and reduced heat load on the limiter may significantly retard impurity generation. Furthermore, it seems to be compatible with reactor engineering requirements. (author)

  19. Enthalpy-based equation of state for highly porous materials employing modified soft sphere fluid model

    Science.gov (United States)

    Nayak, Bishnupriya; Menon, S. V. G.

    2018-01-01

    Enthalpy-based equation of state based on a modified soft sphere model for the fluid phase, which includes vaporization and ionization effects, is formulated for highly porous materials. Earlier developments and applications of enthalpy-based approach had not accounted for the fact that shocked states of materials with high porosity (e.g., porosity more than two for Cu) are in the expanded fluid region. We supplement the well known soft sphere model with a generalized Lennard-Jones formula for the zero temperature isotherm, with parameters determined from cohesive energy, specific volume and bulk modulus of the solid at normal condition. Specific heats at constant pressure, ionic and electronic enthalpy parameters and thermal excitation effects are calculated using the modified approach and used in the enthalpy-based equation of state. We also incorporate energy loss from the shock due to expansion of shocked material in calculating porous Hugoniot. Results obtained for Cu, even up to initial porosities ten, show good agreement with experimental data.

  20. Influence Of Collapsing Matter On The Enveloping Expanding Universe

    OpenAIRE

    Choudhury, A. Latif

    2005-01-01

    Using a collapsing matter model at the center of an expanding universe as described by Weinberg we assume a special type of generated pressure. This pressure transmits into the surrounding expanding universe. Under certain restriction the ensuing hubble parameter is positive. The deacceleration parameter fluctuates with time, indicating that the universe accelerates for certain time and decelerates for other time intervals.

  1. Analogue cosmological particle creation: Quantum correlations in expanding Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Prain, Angus; Liberati, Stefano; Fagnocchi, Serena

    2010-01-01

    We investigate the structure of quantum correlations in an expanding Bose-Einstein condensate (BEC) through the analogue gravity framework. We consider both a 3+1 isotropically expanding BEC as well as the experimentally relevant case of an elongated, effectively 1+1 dimensional, expanding condensate. In this case we include the effects of inhomogeneities in the condensate, a feature rarely included in the analogue gravity literature. In both cases we link the BEC expansion to a simple model for an expanding spacetime and then study the correlation structure numerically and analytically (in suitable approximations). We also discuss the expected strength of such correlation patterns and experimentally feasible BEC systems in which these effects might be detected in the near future.

  2. The Expanding Digital Media Landscape of Qualitative and Decolonizing Research: Examining Collaborative Podcasting as a Research Method

    Directory of Open Access Journals (Sweden)

    Lindsay Day

    2017-12-01

    Full Text Available Technology of the twenty-first century has transformed our ability to create, modify, store, and share digital media and, in so doing, has presented new possibilities for how social science research can be conducted and mobilized. This paper introduces the use of collaborative podcasting as a research method of critical inquiry and knowledge mobilization. Using a case study, we describe the methodological process that our transdisciplinary team engaged in to create the Water Dialogues podcast, a collaborative initiative stemming from a larger research project examining approaches to implementing Indigenous and Western knowledge in water research and management. We situate collaborative podcasting within an expanding field of collaborative and participatory media practice in social research, and consider how the method may align with and support research within a decolonizing agenda.

  3. Chronic expanding hematoma in the retroperitoneal space: a case report

    Science.gov (United States)

    2013-01-01

    Background Chronic expanding hematoma is a rare condition that develops after surgery, trauma, or injury. It can also develop at any location in the body in the absence of trauma. Clinical findings and various diagnostic imaging modalities can aid in the differential diagnosis of this condition. In general, hematomas are naturally reabsorbed and rarely cause serious problems. However, hematomas that develop slowly without a history of trauma, surgery, or bleeding disorders could be difficult to differentiate from soft tissue neoplasms. In the present case, we describe a patient, without any history or physical evidence of trauma, who exhibited a large chronic expanding hematoma in the retroperitoneal space that resulted in hydronephrosis because of the pressure exerted on the left ureter. Case presentation A 69-year-old man presented to our hospital with a swollen lesion in the left flank. A mass, 19 cm in diameter, was detected in the retroperitoneal space by computed tomography. We suspected the presence of a chronic expanding hematoma, soft tissue tumor, or left renal artery aneurysm. Surgical treatment was performed. However, postoperative histopathological examination indicated that the mass was a nonmalignant chronic expanding hematoma. No recurrence was observed during a 2-year follow-up period. Conclusion In patients without a history of trauma who present slowly growing masses, the differential diagnosis should include chronic expanding hematoma in addition to cysts and soft tissue tumors. Moreover, the use of magnetic resonance imaging and computed tomography is essential to differentiate between chronic expanding hematoma and soft tissue tumors. PMID:24237992

  4. Embolization of gastroduodenal artery pseudoaneurysm caused by chronic pancreatitis: a case report

    International Nuclear Information System (INIS)

    Kim, Se Jong; Ko, Kang Seok; Park, Byung Lan; Kim, Byong Geun; Kim, Jae Kyu

    1993-01-01

    Pseudoaneurysm due to chronic pancreatitis is uncommon, but it can cause recurrent and massive hemorrhage. Because of high morbidity and mortality associated with the pseudoaneurysm, early detection and treatment is essential. Surgical ligation or resection of the aneurysm has a high mortality and therefore, transcatheter embolization is preferably carried out. We report a case in which gastroduodenal artery pseudoaneurysm caused by chronic pancreatitis was successfully treated by transcatheter embolization using Gelfoam and Gianturco spring coils

  5. Embolization of gastroduodenal artery pseudoaneurysm caused by chronic pancreatitis: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Se Jong; Ko, Kang Seok; Park, Byung Lan; Kim, Byong Geun [Kwangju Christian Hospital, Gwangju (Korea, Republic of); Kim, Jae Kyu [College of Medicine, Chonnam National Univrsity, Gwangju (Korea, Republic of)

    1993-01-15

    Pseudoaneurysm due to chronic pancreatitis is uncommon, but it can cause recurrent and massive hemorrhage. Because of high morbidity and mortality associated with the pseudoaneurysm, early detection and treatment is essential. Surgical ligation or resection of the aneurysm has a high mortality and therefore, transcatheter embolization is preferably carried out. We report a case in which gastroduodenal artery pseudoaneurysm caused by chronic pancreatitis was successfully treated by transcatheter embolization using Gelfoam and Gianturco spring coils.

  6. Small Engines as Bottoming Cycle Steam Expanders for Internal Combustion Engines

    OpenAIRE

    Weerasinghe, Rohitha; Hounsham, Sandra

    2017-01-01

    Heat recovery bottoming cycles for internal combustion engines have opened new avenues for research into small steam expanders [1]. Dependable data for small steam expanders will allow us to predict on their suitability as bottoming cycle engines and the fuel economy achieved by using them as bottoming cycles. Wankel Engines, with its lower resistance properties at small scale provide excellent contenders for bottoming cycle expanders. Present paper is based on results of experiments carried ...

  7. Experimental Investigation of the Performance of a Hermetic Screw-Expander Organic Rankine Cycle

    Directory of Open Access Journals (Sweden)

    Sung-Wei Hsu

    2014-09-01

    Full Text Available In this study, the authors experimentally investigate the performance of the organic Rankine cycle (ORC and screw expander under the influence of supply pressure and pressure ratio over the expander. Three tests were performed with expander pressure ratios of 2.4–3.5, 3.0–4.6, and 3.3–6.1, which cover the over-expansion and under-expansion operating modes. The test results show a maximum expander isentropic efficiency of 72.4% and a relative cycle efficiency of 10.5% at an evaporation temperature of 101 °C and condensation temperature of 45 °C. At a given pressure ratio over the expander, a higher supply pressure to the expander causes a higher expander isentropic efficiency and higher cycle efficiency in the over-expansion mode. However, in the under-expansion mode, the higher supply pressure results in a lower expander isentropic efficiency and adversely affects the cycle efficiency. The results also show that under the condition of operation at a given pressure ratio, a higher supply pressure yields a larger power output owing to the increased mass flow rate at the higher supply pressure. The study results demonstrate that a screw-expander ORC can be operated with a wide range of heat sources and heat sinks with satisfactory cycle efficiency.

  8. Generating higher-order Lie algebras by expanding Maurer-Cartan forms

    International Nuclear Information System (INIS)

    Caroca, R.; Merino, N.; Salgado, P.; Perez, A.

    2009-01-01

    By means of a generalization of the Maurer-Cartan expansion method, we construct a procedure to obtain expanded higher-order Lie algebras. The expanded higher-order Maurer-Cartan equations for the case G=V 0 +V 1 are found. A dual formulation for the S-expansion multialgebra procedure is also considered. The expanded higher-order Maurer-Cartan equations are recovered from S-expansion formalism by choosing a special semigroup. This dual method could be useful in finding a generalization to the case of a generalized free differential algebra, which may be relevant for physical applications in, e.g., higher-spin gauge theories.

  9. Dynamical 3-Space: Black Holes in an Expanding Universe

    Directory of Open Access Journals (Sweden)

    Rothall D. P.

    2013-10-01

    Full Text Available Black holes are usually studied without including effects of the expanding universe. However in some recent studies black holes have been embedded in an expanding universe, in order to determine the interplay, if any, of these two dynamical processes. Dynamical 3-space theory contains time independent solutions for black holes, which are spatial in-flows, and separately the time dependent Hubble expansion. This theory has explained numerous puzzles in observational astrophysics and contains 3 constants; G, - which from experimental data turns out to be the fine structure constant, and - which is a small but nonzero distance, possibly a Planck-type length. The Hubble expansion in the dynamical 3-space theory cannot be “switched o”, forcing the study, first, of isolated black holes coexisting with the expanding universe. It is shown that a time dependent black hole and expanding universe solution exists. The nature and implications of these solutions are discussed as they evolve over time. A dynamical network of black holes and induced linking cosmic filaments forming bubble structures is discussed, as a consequence of dynamical 3-space undergoing a dynamical breakdown of homogeneity and isotropy, even in the absence of baryonic matter.

  10. 'In situ' expanded graphite extinguishant

    International Nuclear Information System (INIS)

    Cao Qixin; Shou Yuemei; He Bangrong

    1987-01-01

    This report is concerning the development of the extinguishant for sodium fire and the investigation of its extinguishing property. The experiment result shows that 'in situ' expanded graphite developed by the authors is a kind of extinguishant which extinguishes sodium fire quickly and effectively and has no environment pollution during use and the amount of usage is little

  11. The microbiome and colorectal neoplasia: environmental modifiers of dysbiosis.

    Science.gov (United States)

    Turner, N D; Ritchie, L E; Bresalier, R S; Chapkin, R S

    2013-09-01

    The etiology of colon cancer is complex, yet it is undoubtedly impacted by intestinal microbiota. Whether the contribution to colon carcinogenesis is generated through the presence of an overall dysbiosis or by specific pathogens is still a matter for debate. However, it is apparent that interactions between microbiota and the host are mediated by a variety of processes, including signaling cascades, the immune system, host metabolism, and regulation of gene transcription. To fully appreciate the role of microbiota in colon carcinogenesis, it will be necessary to expand efforts to define populations in niche environments, such as colonic crypts, explore cross talk between the host and the microbiota, and more completely define the metabolomic profile of the microbiota. These efforts must be pursued with appreciation that dietary substrates and other environmental modifiers mediate changes in the microbiota, as well as their metabolism and functional characteristics.

  12. An Expanding Universe in the Classroom.

    Science.gov (United States)

    Chandler, David

    1991-01-01

    Two computer-generated star charts that can be used as overlay transparencies to show an expanding universe are presented. Directions on how to use the star charts to determine the Hubble constant and the age of the universe are provided. (KR)

  13. Expanding Your Horizon 2015

    CERN Multimedia

    Kaltenhauser, Kristin

    2015-01-01

    Expanding your horizons is a bi-annual “Science Day” for girls aged 11 to 14, held at the University of Geneva on 14 November. The girls had the opportunity to take part in hands-on workshops held by local professional women in the field of science, mathematics, engineering and technology. For the fourth time, CERN was part of this event, offering three workshops as well as a booth at the Discovery Fair, including Higgnite, an interactive visualization of the Higgs Field.

  14. Production of durable expanded perlite microspheres in a Vertical Electrical Furnace

    Science.gov (United States)

    Panagiotis, M.; Angelopoulos, P.; Taxiarchou, M.; Paspaliaris, I.

    2016-04-01

    Expanded perlite constitutes one of the most competitive insulating materials that is widely used in construction and manufacturing industry due to its unique properties combination; it is white, natural, lightweight, chemically inert, and exhibits superior insulating properties (thermal and acoustic) and fire resistance. Conventionally, perlite expansion is performed in vertical gas-fired furnaces; the conventional perlite expansion process has certain disadvantages which affect expanded products quality, thus limiting their performance and range of applications. In order to overcome the drawbacks of the conventional expansion technique, a new perlite expansion process has been designed based on a vertical electrical furnace (VEF). In the current study, fine perlite samples (-150 μm) from Milos Island, Greece, were expansed in the novel VEF and a conventional gas-fired furnace with the aim to evaluate and compare the main physical properties of the expanded products. The novel expanded perlite particles were characterised by superior properties, namely increased compression strength, competitive water and oil absorption capability, size homogeneity, spherical shape and decreased surface porosity in comparison to conventionally expanded samples.

  15. Expanded Stem Cells, Stromal-Vascular Fraction, and Platelet-Rich Plasma Enriched Fat: Comparing Results of Different Facial Rejuvenation Approaches in a Clinical Trial.

    Science.gov (United States)

    Rigotti, Gino; Charles-de-Sá, Luiz; Gontijo-de-Amorim, Natale Ferreira; Takiya, Christina Maeda; Amable, Paola Romina; Borojevic, Radovan; Benati, Donatella; Bernardi, Paolo; Sbarbati, Andrea

    2016-03-01

    In a previous study, the authors demonstrated that treatment with expanded adipose-derived stem cells or stromal vascular fraction (SVF)-enriched fat modify the pattern of the dermis in human beings, representing a skin rejuvenation effect. Considering that expanded stem cells require a cell factor, the authors wanted to assess similar results by replacing them with platelet-rich plasma (PRP), which is easier to obtain and for which an empirical regenerative effect has been already described. To determine if PRP injection could replace the cutaneous regenerative effect of adipose-derived stem cells. This study was performed in 13 patients who were candidates for facelift. The patients underwent sampling of fat by liposuction from the abdomen and submitted to one of three protocols: injection of SVF-enriched fat or expanded adipose-derived stem cells or fat plus PRP in the preauricular areas. Fragments of skin were removed before and 3 months after treatment and analyzed by optical and electron microscopy. The use of fat plus PRP led to the presence of more pronounced inflammatory infiltrates and a greater vascular reactivity, increasing in vascular permeability and a certain reactivity of the nervous component. The addition of PRP did not improve the regenerative effect. The use of PRP did not have significant advantages in skin rejuvenation over the use of expanded adipose-derived stem cells or SVF-enriched fat. The effect of increased vascular reactivity may be useful in pathological situations in which an intense angiogenesis is desirable, such as tissular ischemia. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  16. Functional Self-Expandable Metal Stents in Biliary Obstruction

    Science.gov (United States)

    Kwon, Chang-Il; Ko, Kwang Hyun; Hahm, Ki Baik

    2013-01-01

    Biliary stents are widely used not only for palliative treatment of malignant biliary obstruction but also for benign biliary diseases. Each plastic stent or self-expandable metal stent (SEMS) has its own advantages, and a proper stent should be selected carefully for individual condition. To compensate and overcome several drawbacks of SEMS, functional self-expandable metal stent (FSEMS) has been developed with much progress so far. This article looks into the outcomes and defects of each stent type for benign biliary stricture and describes newly introduced FSEMSs according to their functional categories. PMID:24143314

  17. Expanding Your Horizons Conference in Geneva

    CERN Multimedia

    Chromek-Burckhart, Doris

    2011-01-01

    CERN and its experiments participated in Expanding Your Horizons (EYH) in Science and Mathematics conference in Geneva on 12th November. EYH nurture girls' interest in science and math courses to encourage them to consider careers in science, technology, engineering, and math.

  18. Expanding economic opportunities in protracted displacement

    OpenAIRE

    Miki Takahashi; Michael Moroz; Jonathan Peters; Jason Pronyk; Richard Barltrop

    2018-01-01

    Welcome progress has been made towards realising commitments made by international donors and host country governments to expand economic opportunities for Syrian refugees and host communities in neighbouring countries. However targets and commitments also bring new challenges, and evidence must underpin new policies.

  19. Expanding Advanced Civilizations in the Universe

    Science.gov (United States)

    Gros, C.

    The 1950 lunch-table remark by Enrico Fermi `Where is everybody' has started intensive scientific and philosophical discussions about what we call nowadays the `Fermi paradox': If there had been ever a single advanced civilization in the cosmological history of our galaxy, dedicated to expansion, it would have had plenty of time to colonize the entire galaxy via exponential growth. No evidence of present or past alien visits to earth are known to us, leading to the standard conclusion that no advanced expanding civilization has ever existed in the milky-way. This conclusion rest fundamentally on the ad-hoc assumption, that any alien civilizations dedicated to expansion at one time would remain dedicated to expansions forever. Considering our limited knowledge about alien civilizations we need however to relax this basic assumption. Here we show that a substantial and stable population of expanding advanced civilization might consequently exist in our galaxy.

  20. Numerical simulation of a twin screw expander for performance prediction

    Science.gov (United States)

    Papes, Iva; Degroote, Joris; Vierendeels, Jan

    2015-08-01

    With the increasing use of twin screw expanders in waste heat recovery applications, the performance prediction of these machines plays an important role. This paper presents a mathematical model for calculating the performance of a twin screw expander. From the mass and energy conservation laws, differential equations are derived which are then solved together with the appropriate Equation of State in the instantaneous control volumes. Different flow processes that occur inside the screw expander such as filling (accompanied by a substantial pressure loss) and leakage flows through the clearances are accounted for in the model. The mathematical model employs all geometrical parameters such as chamber volume, suction and leakage areas. With R245fa as working fluid, the Aungier Redlich-Kwong Equation of State has been used in order to include real gas effects. To calculate the mass flow rates through the leakage paths formed inside the screw expander, flow coefficients are considered as constant and they are derived from 3D Computational Fluid Dynamic calculations at given working conditions and applied to all other working conditions. The outcome of the mathematical model is the P-V indicator diagram which is compared to CFD results of the same twin screw expander. Since CFD calculations require significant computational time, developed mathematical model can be used for the faster performance prediction.

  1. Gout: a review of non-modifiable and modifiable risk factors

    Science.gov (United States)

    MacFarlane, Lindsey A.; Kim, Seoyoung C.

    2014-01-01

    Gout is a common inflammatory arthritis triggered by the crystallization of uric acid within the joints. Gout affects millions worldwide and has an increasing prevalence. Recent research has been carried out to better qualify and quantify the risk factors predisposing individuals to gout. These can largely be broken into non-modifiable risk factors such as sex, age, race, and genetics, and modifiable risk factors such as diet and lifestyle. Increasing knowledge of factors predisposing certain individuals to gout could potentially lead to improved preventive practices. This review summarizes the non-modifiable and modifiable risk factors associated with development of gout. PMID:25437279

  2. Expanded austenite, crystallography and residual stress

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Hummelshøj, Thomas Strabo; Somers, Marcel A. J.

    2010-01-01

    The identity of expanded austenite as developing during low temperature nitriding and/or carburising of austenitic stainless steel has been under debate since the very first observation of this phase. In the present article, recent results obtained with (a) homogeneous samples of various uniform ...

  3. Expanded austenite; crystallography and residual stress

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Hummelshøj, Thomas Strabo; Somers, Marcel A. J.

    2009-01-01

    The identity of expanded austenite as developing during low temperature nitriding and/or carburizing of austenitic stainless steel has been under debate since the very first observation of this phase. In the present article recent results obtained with i) homogeneous samples of various uniform co...

  4. Detection of Genetically Modified Food: Has Your Food Been Genetically Modified?

    Science.gov (United States)

    Brandner, Diana L.

    2002-01-01

    Explains the benefits and risks of genetically-modified foods and describes methods for genetically modifying food. Presents a laboratory experiment using a polymerase chain reaction (PCR) test to detect foreign DNA in genetically-modified food. (Contains 18 references.) (YDS)

  5. Coping with expanding nursing practice, knowledge, and technology.

    Science.gov (United States)

    Gaudinski, M A

    1979-10-01

    Nurses utilize transcultural, transactional, systems, primary, and interdisciplinary approaches to physiological and psychosocial components of patient care. Expanded roles, as well as advances in knowledge and technology have prepared nurses for critical, specialized, primary, aerospace, and independent nursing practice. Exciting as they are, nursing's expanded roles and practices frequently contribute to the burnout and distress phenomena increasingly observed in practicing health care professionals. Causes and symptoms of the burnout distress phenomena are many and varied. Selye, Shubin, Maslach, and others adeptly identified and wrote on the phenomena as it specifically relates to nurses and the many facets of nursing practice. Rather than utilizing crisis intervention coping techniques, preventive strategies and adaptations are suggested. This paper reviews and discusses: 1. Factors associated with burnout-distress phenomena identified in professional literature; 2. Identification of factors associated with expanded roles and practice which contribute to burnout stress; 3. Identification of factors in military and civilian air ambulance and aeromedical evacuation systems which contribute to burnout stress; 4. Recommendations for strategies to prevent and cope with burnout distress factors.

  6. Dynamics of a radially expanding liquid sheet: Experiments

    Science.gov (United States)

    Majumdar, Nayanika; Tirumkudulu, Mahesh

    2017-11-01

    A recent theory predicts that sinuous waves generated at the center of a radially expanding liquid sheet grow spatially even in absence of a surrounding gas phase. Unlike flat liquid sheets, the thickness of a radially expanding liquid sheet varies inversely with distance from the center of the sheet. To test the predictions of the theory, experiments were carried out on a horizontal, radially expanding liquid sheet formed by collision of a single jet on a solid impactor. The latter was placed on a speaker-vibrator with controlled amplitude and frequency. The growth of sinuous waves was determined by measuring the wave surface inclination angle using reflected laser light under both atmospheric and sub-atmospheric pressure conditions. It is shown that the measured growth rate matches with the predictions of the theory over a large range of Weber numbers for both pressure conditions suggesting that the thinning of the liquid sheet plays a dominant role in setting the growth rate of sinuous waves with minimal influence of the surrounding gas phase on its dynamics. IIT Bombay.

  7. Why has medicine expanded? The role of consumers.

    Science.gov (United States)

    Zheng, Hui

    2015-07-01

    In the past 50years, the field of medicine has expanded dramatically in many Western societies. Despite substantial improvements in objective health measures, there has not been a commensurate increase in assessments of subjective health. We hypothesize that medical expansion may lower people's subjective health perceptions, leading to an increase in health care utilization, and, in turn, fueling further medical expansion. We use OECD (Organization for Economic Co-operation and Development) Health Data, World Development Indicators, the World Values Survey, and the European Values Study to fit a difference-in-differences model that removes unobserved cross-national heterogeneity and any period trend that is shared across nations. We find that three dimensions of medical expansion at the societal level (medical investment, medical professionalization/specialization, and an expanded pharmaceutical industry) negatively affect individual subjective health. These findings are robust to different model specifications. We conclude by discussing possible explanations for the adverse effect of medical expansion on subjective health, and how this effect may be related to other mechanisms through which medicine expands. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. A 100-Year Review: Metabolic modifiers in dairy cattle nutrition.

    Science.gov (United States)

    McGuffey, R K

    2017-12-01

    The first issue of the Journal of Dairy Science in 1917 opened with the text of the speech by Raymond A. Pearson, president of the Iowa State College of Agriculture, at the dedication of the new dairy building at the University of Nebraska (J. Dairy Sci. 1:4-18, 1917). Fittingly, this was the birth of a new research facility and more importantly, the beginning of a new journal devoted to the sciences of milk production and manufacture of products from milk. Metabolic modifiers of dairy cow metabolism enhance, change, or interfere with normal metabolic processes in the ruminant digestive tract or alter postabsorption partitioning of nutrients among body tissues. Papers on metabolic modifiers became more frequent in the journal around 1950. Dairy farming changed radically between 1955 and 1965. Changes in housing and feeding moved more cows outside, and cows and heifers in all stages of lactation, including the dry period, were fed as a single group. Rations became wetter with the shift to corn silage as the major forage in many rations. Liberal grain feeding met the requirements of high-producing cows and increased production per cow but introduced new challenges; for example, managing and feeding cows as a group. These changes led to the introduction of new strategies that identified and expanded the use of metabolic modifiers. Research was directed at characterizing the new problems for the dairy cow created by group feeding. Metabolic modifiers went beyond feeding the cow and included environmental and housing factors and additives to reduce the incidence and severity of many new conditions and pathologies. New collaborations began among dairy cattle specialties that broadened our understanding of the workings of the cow. The Journal of Dairy Science then and now plays an enormously important role in dissemination of the findings of dairy scientists worldwide that address existing and new technologies. Copyright © 2017 American Dairy Science Association

  9. ASPS clinical practice guideline summary on breast reconstruction with expanders and implants.

    Science.gov (United States)

    Alderman, Amy; Gutowski, Karol; Ahuja, Amy; Gray, Diedra

    2014-10-01

    After reading this article, participants should be able to: 1. Understand the evidence regarding the timing of expander/implant breast reconstruction in the setting of radiation therapy. 2. Discuss the implications of a patient's risk factors for possible outcomes and complications of expander/implant breast reconstruction. 3. Implement proper prophylactic antibiotic protocols. 4. Use the guidelines to improve their own clinical outcomes and reduce complications. In March of 2013, the Executive Committee of the American Society of Plastic Surgeons approved an evidence-based guideline on breast reconstruction with expanders and implants, as developed by a guideline-specific work group commissioned by the society's Health Policy Committee. The guideline addresses ten clinical questions: patient education, immediate versus delayed reconstruction, risk factors, radiation therapy, chemotherapy, hormonal therapy, antibiotic prophylaxis, acellular dermal matrix, monitoring for cancer recurrence, and oncologic outcomes associated with implant-based reconstruction. The evidence indicates that patients undergoing mastectomy should be offered a preoperative referral to a plastic surgeon. Evidence varies regarding the association between postoperative complications and timing of postmastectomy expander/implant breast reconstruction. Evidence is limited regarding the optimal timing of expand/implant reconstruction in the setting of radiation therapy but suggests that irradiation to the expander or implant is associated with an increased risk of postoperative complications. Evidence also varies regarding the association between acellular dermal matrix and surgical complications in the setting of postmastectomy expander/implant reconstruction. Data support the use of an appropriate preoperative antibiotic, but antibiotics should be discontinued within 24 hours of the procedure, unless a surgical drain is present. Furthermore, postmastectomy expander/implant breast reconstruction

  10. Expanding economic opportunities in protracted displacement

    Directory of Open Access Journals (Sweden)

    Miki Takahashi

    2018-02-01

    Full Text Available Welcome progress has been made towards realising commitments made by international donors and host country governments to expand economic opportunities for Syrian refugees and host communities in neighbouring countries. However targets and commitments also bring new challenges, and evidence must underpin new policies.

  11. Magnetic fields in an expanding universe

    International Nuclear Information System (INIS)

    Kastor, David; Traschen, Jennie

    2014-01-01

    We find a solution to 4D Einstein–Maxwell theory coupled to a massless dilaton field, for all values of the dilaton coupling, describing a Melvin magnetic field in an expanding universe with ‘stiff matter’ equation of state parameter w = +1. As the universe expands, magnetic flux becomes more concentrated around the symmetry axis for dilaton coupling a<1/√3 and more dispersed for a>1/√3. An electric field circulates around the symmetry axis in the direction determined by Lenz's law. For a = 0 the magnetic flux through a disc of fixed comoving radius is proportional to the proper area of the disc. This result disagrees with the usual expectation based on a test magnetic field that this flux should be constant, and we show why this difference arises. We also find a Melvin solution in an accelerating universe with w = −7/9 for a dilaton field with a certain exponential potential. (paper)

  12. Transcatheter arterial embolization of a pseudoaneurysm of gastroduodenal artery: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Han, Young Min; Kang, Sung Soo; Lee, Jeong Min; Chung, Jin Young; Lee, Sang Yong; Chung, Gyung Ho; Kim, Chong Soo; Sohn, Myung Hee; Choi, Ki Chul [Chonbuk National University School of Medicine, Chonju (Korea, Republic of)

    1997-01-01

    Gastroduodenal artery pseudoaneurysm is a relatively rare and potentionally life-threatening complication of chronic pancreatitis, which is thought to occur because of autodigestion of arterial walls by pancreatic enzymes. Embolotherapy should probably be the first method of treatment, since surgical treatment carries a high risk of mortality and morbidity. We report the case of 30-year-old male with gastroduodenal artery pseudoaneurysm caused by chronic pancreatitis which was successfully treated by transcatheter embolization using Gianturco spring coils.

  13. Transcatheter arterial embolization of a pseudoaneurysm of gastroduodenal artery: a case report

    International Nuclear Information System (INIS)

    Han, Young Min; Kang, Sung Soo; Lee, Jeong Min; Chung, Jin Young; Lee, Sang Yong; Chung, Gyung Ho; Kim, Chong Soo; Sohn, Myung Hee; Choi, Ki Chul

    1997-01-01

    Gastroduodenal artery pseudoaneurysm is a relatively rare and potentionally life-threatening complication of chronic pancreatitis, which is thought to occur because of autodigestion of arterial walls by pancreatic enzymes. Embolotherapy should probably be the first method of treatment, since surgical treatment carries a high risk of mortality and morbidity. We report the case of 30-year-old male with gastroduodenal artery pseudoaneurysm caused by chronic pancreatitis which was successfully treated by transcatheter embolization using Gianturco spring coils

  14. The Army’s Military Decision Making: Adequate or Update and Expand

    Science.gov (United States)

    2008-05-22

    requires creative efforts by every Soldier and Marine.”63 Expanding the soldier base would allow for greater creativity in order to better deal with...military can overcome these deficiencies? I believe that to achieve the initial stage of success would be to create a segment of soldier telecommuters ...problems. By expanding the thinking base, the Army can expand the breadth and depth into areas currently unreachable. Telecommuting allows for several

  15. Performance study of a twin-screw expander used in a geothermal organic Rankine cycle power generator

    International Nuclear Information System (INIS)

    Tang, Hao; Wu, Huagen; Wang, Xiaolin; Xing, Ziwen

    2015-01-01

    The ORC (organic Rankine cycle) system is an effective technology to generate electricity from low temperature heat sources. The twin-screw expander is a key component that is commonly used in the small-to-medium capacity ORC system to convert thermal energy into work. In this paper, the performance of a twin-screw expander is theoretically and experimentally studied. A mathematical model is developed and subsequently validated using experimental data. The effect of several important factors including expander speed, suction pressure and inlet superheat on the expander performance is investigated. Results indicate that the expander speed and suction pressure have large influences on the expander performance, while the inlet superheat has relatively small effect. The isentropic efficiency of the expander decreases from 0.88 to 0.6 and the expander volumetric efficiency decreases from 0.88 to 0.7 as the expander rotational speed increases from 1250 to 6000 rpm. The results further show that the expander volumetric efficiency decreases from 0.91 to 0.85 as the expander suction pressure increases from 0.33 to 0.47 MPa. Furthermore, the energy conversion efficiency of the studied ORC system using the twin-screw expander is as high as 7.5% under the site conditions. - Highlights: • Performance of a twin-screw expander used in an ORC (organic Rankine cycle) system was studied. • A thermodynamic model was developed for this purpose and experimentally validated. • Effect of several key factors on the expander performance was investigated. • Suction pressure has a large influence on the expander performance. • Twin-screw expanders can be operated with a wide range of heat source temperatures.

  16. Custom Ontologies for Expanded Network Analysis

    Science.gov (United States)

    2006-12-01

    for Expanded Network Analysis. In Visualising Network Information (pp. 6-1 – 6-10). Meeting Proceedings RTO-MP-IST-063, Paper 6. Neuilly-sur-Seine...Even to this day, current research groups are working to develop an approach that involves taking all available text, video, imagery and audio and

  17. Effect of expansion temperature of expandable graphite on microstructure evolution of expanded graphite during high-energy ball-milling

    International Nuclear Information System (INIS)

    Yue Xueqing; Li Liang; Zhang Ruijun; Zhang Fucheng

    2009-01-01

    Two expanded graphites (EG), marked as EG-1 and EG-2, were prepared by rapid heating of expandable graphite to 600 and 1000 deg. C, respectively, and ball milled in a high-energy mill (planetary-type) under air atmosphere. The microstructure evolution of the ball-milled samples was characterized by X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). XRD analysis shows that the evolution degree of the average crystallite thickness along the c-axis (L c ) of EG-2 is lower than that of EG-1 during the milling process. From the HRTEM images of the samples after 100 h ball-milling, slightly curved graphene planes can be frequently observed both in the two EGs, however, EG-1 and EG-2 exhibit sharply curved graphene planes and smoothly curved graphene planes with high bending angles, respectively.

  18. Effects of silicone expanders and implants on echocardiographic image quality after breast reconstruction.

    Science.gov (United States)

    Pignatti, Marco; Mantovani, Francesca; Bertelli, Luca; Barbieri, Andrea; Pacchioni, Lucrezia; Loschi, Pietro; De Santis, Giorgio

    2013-08-01

    Use of silicone expanders and implants is the most common breast reconstruction technique after mastectomy. Postmastectomy patients often need echocardiographic monitoring of potential cardiotoxicity induced by cancer chemotherapy. The impairment of the echocardiographic acoustic window caused by silicone implants for breast augmentation has been reported. This study investigates whether the echocardiographic image quality was impaired in women reconstructed with silicone expanders and implants. The records of 44 consecutive women who underwent echocardiographic follow-up after breast reconstruction with expanders and implants at the authors' institution from January of 2000 to August of 2012 were reviewed. The population was divided into a study group (left or bilateral breast expanders/implants, n=30) and a control group (right breast expanders/implants, n=14). The impact of breast expanders/implants on echocardiographic image quality was tested (analysis of covariance model). Patients with a breast expander/implant (left or bilateral and right breast expanders/implants) were included. The mean volume of the breast devices was 353.2±125.5 cc. The quality of the echocardiographic images was good or sufficient in the control group; in the study group, it was judged as adequate in only 50 percent of cases (15 patients) and inadequate in the remaining 15 patients (pimplants in postmastectomy left breast reconstruction considerably reduce the image quality of echocardiography. This may have important clinical implications, given the need for periodic echocardiographic surveillance before and during chemotherapy. Therapeutic, III.

  19. Interlayer expanded molybdenum disulfide nanosheets assembly for electrochemical supercapacitor with enhanced performance

    International Nuclear Information System (INIS)

    Xiao, Huaqing; Wang, Shutao; Zhang, Shuo; Wang, Yihe; Xu, Qingfei; Hu, Wenjie; Zhou, Yan; Wang, Zhaojie; An, Changhua; Zhang, Jun

    2017-01-01

    Rational structural design for electrode materials is essential for fabricating high performance supercapacitors. In this work, we demonstrated a novel way to prepare incompact MoS_2 nanosheets assembled nanorods with the interlayer of MoS_2 nanosheets expanded to 0.89 nm, namely layer expanded MoS_2 nanorods (LE-MoS_2 NRs). The material was characterized by XRD, XPS and electron microscopes. The XRD data and HRTEM images confirmed the existence of expanded interlayer of MoS_2 nanosheets. N_2 adsorption-desorption isotherms of LE-MoS_2 NRs indicated high specific area up to 37.0 m"2 g"−"1. It was found that the expanded interlayer spacing can benefit the ion transportation within the MoS_2 interlayers. The as-prepared electrode material showed capacitance up to 231 F g"−"1 at 1 A g"−"1 charge-discharge current and cycling stability test indicated high capacitance of 177 F g"−"1 was retained after 1000 cycles. - Highlights: • High performance electrochemical supercapacitor electrode material. • Interlayer expanded MoS_2 to achieve enhanced capacitance. • Facile hydrothermal synthesis of interlayer expanded MoS_2. • MoS_2 nanosheets assembled incompact nanorods.

  20. Industrial implementation of plasma deposition using the expanding thermal plasma technique

    NARCIS (Netherlands)

    Sanden, van de M.C.M.; Oever, van den P.J.; Creatore, M.; Schaepkens, M.; Miebach, T.; Iacovangelo, C.D.; Bosch, R.C.M.; Bijker, M.D.; Evers, M.F.J.; Schram, D.C.; Kessels, W.M.M.

    2004-01-01

    Two successful industrial implementations of the expanding thermal plasma setup, a novel plasma source, obtaining high deposition rate are discussed. The Ar/O2/hexamethyldisiloxane and Ar/O2/octamethyl-cyclosiloxane-fed expanding thermal plasma setup is used to deposit scratch resistant silicone

  1. DISRUPTIVE TECHNOLOGIES: AN EXPANDED VIEW

    OpenAIRE

    JAMES M. UTTERBACK; HAPPY J. ACEE

    2005-01-01

    The term "disruptive technology" as coined by Christensen (1997, The Innovator's Dilemma; How New Technologies Cause Great Firms to Fail. Harvard Business School Press) refers to a new technology having lower cost and performance measured by traditional criteria, but having higher ancillary performance. Christensen finds that disruptive technologies may enter and expand emerging market niches, improving with time and ultimately attacking established products in their traditional markets. This...

  2. Women Engineering Faculty: Expanding the Pipeline

    Science.gov (United States)

    Greni, Nadene Deiterman

    2006-01-01

    The purpose for this case study was to explore the features of undergraduate engineering departmental and college support that influenced the persistence of women students. Women engineering faculty members were among the participants at three Land Grant universities in the Midwest. The data revealed the theme, Expanding the Pipeline, and…

  3. Modifying the Toyota Production System for continuous performance improvement in an academic children's hospital.

    Science.gov (United States)

    Stapleton, F Bruder; Hendricks, James; Hagan, Patrick; DelBeccaro, Mark

    2009-08-01

    The Toyota Production System (TPS) has become a successful model for improving efficiency and eliminating errors in manufacturing processes. In an effort to provide patients and families with the highest quality clinical care, our academic children's hospital has modified the techniques of the TPS for a program in continuous performance improvement (CPI) and has expanded its application to educational and research programs. Over a period of years, physicians, nurses, residents, administrators, and hospital staff have become actively engaged in a culture of continuous performance improvement. This article provides background into the methods of CPI and describes examples of how we have applied these methods for improvement in clinical care, resident teaching, and research administration.

  4. Adoptive Immunotherapy for Hematological Malignancies Using T Cells Gene-Modified to Express Tumor Antigen-Specific Receptors

    Directory of Open Access Journals (Sweden)

    Hiroshi Fujiwara

    2014-12-01

    Full Text Available Accumulating clinical evidence suggests that adoptive T-cell immunotherapy could be a promising option for control of cancer; evident examples include the graft-vs-leukemia effect mediated by donor lymphocyte infusion (DLI and therapeutic infusion of ex vivo-expanded tumor-infiltrating lymphocytes (TIL for melanoma. Currently, along with advances in synthetic immunology, gene-modified T cells retargeted to defined tumor antigens have been introduced as “cellular drugs”. As the functional properties of the adoptive immune response mediated by T lymphocytes are decisively regulated by their T-cell receptors (TCRs, transfer of genes encoding target antigen-specific receptors should enable polyclonal T cells to be uniformly redirected toward cancer cells. Clinically, anticancer adoptive immunotherapy using genetically engineered T cells has an impressive track record. Notable examples include the dramatic benefit of chimeric antigen receptor (CAR gene-modified T cells redirected towards CD19 in patients with B-cell malignancy, and the encouraging results obtained with TCR gene-modified T cells redirected towards NY-ESO-1, a cancer-testis antigen, in patients with advanced melanoma and synovial cell sarcoma. This article overviews the current status of this treatment option, and discusses challenging issues that still restrain the full effectiveness of this strategy, especially in the context of hematological malignancy.

  5. Porous expandable device for attachment to bone tissue

    Science.gov (United States)

    Rybicki, Edmund F.; Wheeler, Kenneth Ray; Hulbert, Lewis E.; Karagianes, Manuel Tom; Hassler, Craig R.

    1977-01-01

    A device for attaching to substantially solid living bone tissue, comprising a body member having an outer surface shaped to fit approximately into an empty space in the tissue and having pores into which the tissue can grow to strengthen the bond between the device and the tissue, and adjustable means for expanding the body member against the tissue to an extent such as to provide a compressive stress capable of maintaining a snug and stable fit and of enhancing the growth of the tissue into the pores in the body member. The expanding means is adjustable to provide a stress between the tissue and the body member in the range of about 150 to 750 psi, typically 150 to 350 psi. Typically the body member comprises an expandable cylindrical portion having at least one radial slit extending longitudinally from a first end to the vicinity of the opposite (second) end thereof, at least one radial slit extending longitudinally from the second end to the vicinity of the first end thereof, and a tapered cylindrical hole extending coaxially from a wider circular opening in the first end to a narrower circular opening communicating with the second end.

  6. Prospects for expanded utilization of biogas in Germany

    International Nuclear Information System (INIS)

    Poeschl, Martina; Ward, Shane; Owende, Philip

    2010-01-01

    The prospects for expanded utilization of biogas systems in German was analysed, by identifying the operational and policy factors affecting the complete chain of processes from implementation process for biogas plants, through to biogas production and utilization. It was found that the Renewable Energies Act (EEG) and energy tax reliefs provide bases for the support of expanded utilization. Upgrading of biogas to natural gas quality for utilization in the transportation sector was arguably the most promising technology that could support rapid utilization expansion. Sustainable deployment of biogas systems in light of the unstable feedstock prices and availability, and the need for subsidy-free operation in the long term requires; enhancement of feedstock flexibility and quality characteristics to maximise gas yield, and optimisation of the anaerobic digestion process management. Assessment of energy balance and potential environmental impacts of the integrated process chain provides a holistic assessment of sustainability. The results also support the development and foster of policies and framework for development of biogas as environmentally friendly energy resource, among a mix of renewable energy sources, hence, compete favourably with fossil fuels to enhance the prospects for expanded utilization. (author)

  7. Examining Cognitive Status of Elderly Iranians: Farsi Version of the Modified Mini-Mental State Examination.

    Science.gov (United States)

    Gharaeipour, Manouchehr; Andrew, Melissa K

    2013-02-27

    The Modified Mini-Mental State Examination (3MS) is an expanded and modified version of the Mini-Mental State Examination (MMSE). Research demonstrates that the reliability, validity, specificity, and sensitivity of the 3MS are superior to that of the MMSE in detecting cognitive impairment. The Farsi version of the 3MS (F-3MS) was examined as a screening tool for dementia among elderly Iranians. The F-3MS and the Clock Drawing Test (CDT) were administered to 58 patients with dementia and 145 control subjects with normal cognition, aged 60 to 85 years. The difference between groups on the mean total scores of the F-3MS was statistically significant (dementia = 60.65 ± 9.89, control = 80.73 ± 8.26; df = 201, t = 14.75, p validity of the F-3MS. The F-3MS can be used as a valid and reliable measure for dementia screening among elderly Iranians.

  8. Expanding CTE Opportunities through Blended Learning

    Science.gov (United States)

    McKinstry, Elizabeth

    2012-01-01

    The global economy, 21st century skills, knowledge society, college and career readiness, digital and project-based learning are all common terms to educators who are expanding their learning environments beyond the classroom to meet the needs of all students. It is common knowledge that the rapid technological advances of this century have…

  9. Transcatheter Splenic Artery Occlusion for Treatment of Splenic Artery Steal Syndrome After Orthotopic Liver Transplantation

    International Nuclear Information System (INIS)

    Uflacker, Renan; Selby, J. Bayne; Chavin, Kenneth; Rogers, Jeffrey; Baliga, Prabhakar

    2002-01-01

    Purpose: To review some aspects of the problem of splenic artery steal syndrome as cause of ischemia in transplanted livers and treatment by selective splenic artery occlusion. Materials and Methods: Eleven liver transplant patients from a group of 350 patients, nine men and two women,ranging in age from 40 years to 61 years (mean 52 years), presented with biochemical evidences of liver ischemia and failure, ranging from one to 60 days following orthotopic liver transplantation. Diagnosis of splenic artery steal syndrome was suspected by elevated enzymes, Doppler ultrasound and confirmed by celiac angiogram. Patients with confirmed hepatic artery thrombosis before angiography were excluded from the study. Embolization with Gianturco coils was performed. Results: All patients were treated by splenic artery embolization with Gianturco coils. The 11 patients improved clinically within 24 hours of the procedure with significant change in the biochemical and clinical parameters. Followup ranged from one month to two years. One of the 11 patient initially improved, but developed hepatic artery thrombosis within 24 hours of the embolic treatment,requiring surgical repair. Conclusion: Splenicartery steal syndrome following liver transplantation surgery can be diagnosed by celiac angiography, and effectively treated by splenic artery embolization with coils. Embolization is one of the treatments available, it is minimally invasive, and leads to immediate clinical improvement. Hepatic artery thrombosis is a possible complication of the procedure

  10. On the Propagation of Light in an Expanding Universe

    Directory of Open Access Journals (Sweden)

    Yuri Heymann

    2013-07-01

    Full Text Available The equation of the propagation of light in an expanding Universe is derived based on the definition of comoving distances. A numerical method is proposed to solve this equation jointly with the Friedmann equation. As the equation of the propagation of light in an expanding Universe defines a horizon of the visible Universe, this puts a constraint on cosmological models in order to be consistent with an upper limit for redshifts observed from galaxies. This puzzle is challenging current expansionist cosmological models.

  11. Interlayer expanded molybdenum disulfide nanosheets assembly for electrochemical supercapacitor with enhanced performance

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Huaqing; Wang, Shutao; Zhang, Shuo; Wang, Yihe; Xu, Qingfei; Hu, Wenjie [College of Science, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China); Zhou, Yan, E-mail: yanzhou@upc.edu.cn [College of Science, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China); State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China); Wang, Zhaojie [College of Science, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China); An, Changhua [College of Science, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China); College of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin, 300384 (China); Zhang, Jun, E-mail: zhangj@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China)

    2017-05-01

    Rational structural design for electrode materials is essential for fabricating high performance supercapacitors. In this work, we demonstrated a novel way to prepare incompact MoS{sub 2} nanosheets assembled nanorods with the interlayer of MoS{sub 2} nanosheets expanded to 0.89 nm, namely layer expanded MoS{sub 2} nanorods (LE-MoS{sub 2} NRs). The material was characterized by XRD, XPS and electron microscopes. The XRD data and HRTEM images confirmed the existence of expanded interlayer of MoS{sub 2} nanosheets. N{sub 2} adsorption-desorption isotherms of LE-MoS{sub 2} NRs indicated high specific area up to 37.0 m{sup 2} g{sup −1}. It was found that the expanded interlayer spacing can benefit the ion transportation within the MoS{sub 2} interlayers. The as-prepared electrode material showed capacitance up to 231 F g{sup −1} at 1 A g{sup −1} charge-discharge current and cycling stability test indicated high capacitance of 177 F g{sup −1} was retained after 1000 cycles. - Highlights: • High performance electrochemical supercapacitor electrode material. • Interlayer expanded MoS{sub 2} to achieve enhanced capacitance. • Facile hydrothermal synthesis of interlayer expanded MoS{sub 2}. • MoS{sub 2} nanosheets assembled incompact nanorods.

  12. 13 CFR 120.835 - Application to expand an Area of Operations.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Application to expand an Area of Operations. 120.835 Section 120.835 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS... program responsibilities in the proposed area. (b) Local Economic Area Expansion. A CDC seeking to expand...

  13. CFD simulations of compressed air two stage rotary Wankel expander – Parametric analysis

    International Nuclear Information System (INIS)

    Sadiq, Ghada A.; Tozer, Gavin; Al-Dadah, Raya; Mahmoud, Saad

    2017-01-01

    Highlights: • CFD ANSYS-Fluent 3D simulation of Wankel expander is developed. • Single and two-stage expander’s performance is compared. • Inlet and outlet ports shape and configurations are investigated. • Isentropic efficiency of two stage Wankel expander of 91% is achieved. - Abstract: A small scale volumetric Wankel expander is a powerful device for small-scale power generation in compressed air energy storage (CAES) systems and Organic Rankine cycles powered by different heat sources such as, biomass, low temperature geothermal, solar and waste heat leading to significant reduction in CO_2 emissions. Wankel expanders outperform other types of expander due to their ability to produce two power pulses per revolution per chamber additional to higher compactness, lower noise and vibration and lower cost. In this paper, a computational fluid dynamics (CFD) model was developed using ANSYS 16.2 to simulate the flow dynamics for a single and two stage Wankel expanders and to investigate the effect of port configurations, including size and spacing, on the expander’s power output and isentropic efficiency. Also, single-stage and two-stage expanders were analysed with different operating conditions. Single-stage 3D CFD results were compared to published work showing close agreement. The CFD modelling was used to investigate the performance of the rotary device using air as an ideal gas with various port diameters ranging from 15 mm to 50 mm; port spacing varying from 28 mm to 66 mm; different Wankel expander sizes (r = 48, e = 6.6, b = 32) mm and (r = 58, e = 8, b = 40) mm both as single-stage and as two-stage expanders with different configurations and various operating conditions. Results showed that the best Wankel expander design for a single-stage was (r = 48, e = 6.6, b = 32) mm, with the port diameters 20 mm and port spacing equal to 50 mm. Moreover, combining two Wankel expanders horizontally, with a larger one at front, produced 8.52 kW compared

  14. Historical Notes on the Expanding Universe

    Science.gov (United States)

    Way, Michael J.; Belenkyi, Ari; Nussbaumer, Harry; Peacock, John

    2014-01-01

    The article Measuring the Hubble constant by Mario Livio and Adam Riess (Physics Today, October 2013, page 41) reviewed studies of the expanding universe from the 1920s to the present. Although the history of the subject underwent considerable compression to fit the length of a magazine article, we think it may leave a misleading impression of some of the key steps to our current understanding. We therefore offer the following clarifications. Most significantly, papers by Arthur Eddington and by Willem de Sitter in 1930, who successfully promoted Georges Lematres 1927 article for the Scientific Society of Brussels, effected a paradigm shift in interpretation of extragalactic redshifts in 1930. Before then, the astronomical community was generally unaware of the existence of nonstatic cosmological solutions and did not broadly appreciate that redshifts could be thought of locally as Doppler shifts in an expanding matter distribution. Certainly, in 1929 Edwin Hubble referred only to the de Sitter solution of 1917. At the time, the relation between distance and redshift predicted in that model was generally seen purely as a manifestation of static spacetime curvature.

  15. Determination of the concentration dependent diffusion coefficient of nitrogen in expanded austenite

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Somers, Marcel A. J.

    2008-01-01

    The concentration dependent diffusion coefficient of nitrogen in expanded austenite was determined from of the rate of retracting nitrogen from thin initially N-saturated coupons. Nitrogen saturated homogeneous foils of expanded austenite were obtained by nitriding AISI 304 and AISI 316 in pure...... in the composition range where nitrogen can be extracted by hydrogen gas at the diffusion temperature. Numerical simulation of the denitriding experiments shows that the thus determined concentration dependent diffusion coefficients are an accurate approximation of the actual diffusivity of nitrogen in expanded...... ammonia at 693 K and 718 K. Denitriding experiments were performed by equilibrating the foils with a successively lower nitrogen activity, as imposed by a gas mixture of ammonia and hydrogen. The concentration dependent diffusion coefficient of nitrogen in expanded austenite was approximated...

  16. Expanding the Education Universe: A Fifty-State Strategy for Course Choice

    Science.gov (United States)

    Brickman, Michael

    2014-01-01

    After twenty years of expanding school-choice options, state leaders, educators, and families have a new tool: course choice, a strategy for students to learn from unconventional providers that might range from top-tier universities or innovative community colleges to local employers, labs, or hospitals. In "Expanding the Education Universe:…

  17. Reciprocating Expander for an Exhaust Heat Recovery Rankine Cycle for a Passenger Car Application

    Directory of Open Access Journals (Sweden)

    Osoko Shonda

    2012-06-01

    Full Text Available Nowadays, on average, two thirds of the fuel energy consumed by an engine is wasted through the exhaust gases and the cooling liquid. The recovery of this energy would enable a substantial reduction in fuel consumption. One solution is to integrate a heat recovery system based on a steam Rankine cycle. The key component in such a system is the expander, which has a strong impact on the system’s performance. A survey of different expander technologies leads us to select the reciprocating expander as the most promising one for an automotive application. This paper therefore proposes a steady-state semi-empirical model of the expander device developed under the Engineering Equation Solver (EES environment. The ambient and mechanical losses as well as internal leakage were taken into account by the model. By exploiting the expander manufacturer’s data, all the parameters of the expander model were identified. The model computes the mass flow rate, the power output delivered and the exhaust enthalpy of the steam. The maximum deviation between predictions and measurement data is 4.7%. A performance study of the expander is carried out and shows that the isentropic efficiency is quite high and increases with the expander rotary speed. The mechanical efficiency depends on mechanical losses which are quite high, approximately 90%. The volumetric efficiency was also evaluated.

  18. The motion of an isolated gas group in expanding universe

    International Nuclear Information System (INIS)

    Zhang Banggu

    1993-01-01

    The contraction of an isolated gas group in the expanding universe has been discussed. It is found that in addition to the contracted conditions of the static isolated gas group, the initial gas group is straticulate statistical uniform and the initial radius is larger than a critical value D γ -1 , the contracted conditions of expanding case also include that the Hubble constant H is smaller than a constant D t

  19. Intelligent Flexible Materials for Space Structures: Expandable Habitat Engineering Development Unit

    Science.gov (United States)

    Hinkle, Jon; Sharpe, George; Lin, John; Wiley, Cliff; Timmers, Richard

    2010-01-01

    Expandable habitable elements are an enabling technology for human exploration in space and on planetary surfaces. Large geometries can be deployed from a small launch volume, allowing greater mission capability while reducing mass and improving robustness over traditional rigid shells. This report describes research performed by ILC Dover under the Intelligent Flexible Materials for Space Structures program on the design and manufacture of softgoods for LaRC's Expandable Habitat Engineering Development Unit (EDU). The EDU is a full-scale structural test article of an expandable hybrid habitat, integrating an expandable softgoods center section with two rigid end caps. The design of the bladder, restraint layer and a mock-up Thermal Micrometeoroid Cover is detailed together with the design of the interface hardware used to attach them to the end caps. The integration and design of two windows and a floor are also covered. Analysis was performed to study the effects of the open weave design, and to determine the correct webbing and fabric configuration. Stress analyses were also carried out on the interfaces between the softgoods and the end caps and windows. Testing experimentally determined the strength of the fabric and straps, and component testing was used to proof several critical parts of the design. This program established new manufacturing and design techniques that can be applied to future applications in expandable structures.

  20. Measuring the Plasma Density of a Ferroelectric Plasma Source in an Expanding Plasma

    International Nuclear Information System (INIS)

    Dunaevsky, A.; Fisch, N.J.

    2003-01-01

    The initial density and electron temperature at the surface of a ferroelectric plasma source were deduced from floating probe measurements in an expanding plasma. The method exploits negative charging of the floating probe capacitance by fast flows before the expanding plasma reaches the probe. The temporal profiles of the plasma density can be obtained from the voltage traces of the discharge of the charged probe capacitance by the ion current from the expanding plasma. The temporal profiles of the plasma density, at two different distances from the surface of the ferroelectric plasma source, could be further fitted by using the density profiles for the expanding plasma. This gives the initial values of the plasma density and electron temperature at the surface. The method could be useful for any pulsed discharge, which is accompanied by considerable electromagnetic noise, if the initial plasma parameters might be deduced from measurements in expanding plasma

  1. Preparation, quantitative surface analysis, intercalation characteristics and industrial implications of low temperature expandable graphite

    Science.gov (United States)

    Peng, Tiefeng; Liu, Bin; Gao, Xuechao; Luo, Liqun; Sun, Hongjuan

    2018-06-01

    Expandable graphite is widely used as a new functional carbon material, especially as fire-retardant; however, its practical application is limited due to the high expansion temperature. In this work, preparation process of low temperature and highly expandable graphite was studied, using natural flake graphite as raw material and KMnO4/HClO4/NH4NO3 as oxidative intercalations. The structure, morphology, functional groups and thermal properties were characterized during expanding process by Fourier transform infrared spectroscopy (FTIR), Raman spectra, thermo-gravimetry differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), and scanning electron microscope (SEM). The analysis showed that by oxidation intercalation, some oxygen-containing groups were grafted on the edge and within the graphite layer. The intercalation reagent entered the graphite layer to increase the interlayer spacing. After expansion, the original flaky expandable graphite was completely transformed into worm-like expanded graphite. The order of graphite intercalation compounds (GICs) was proposed and determined to be 3 for the prepared expandable graphite, based on quantitative XRD peak analysis. Meanwhile, the detailed intercalation mechanisms were also proposed. The comprehensive investigation paved a benchmark for the industrial application of such sulfur-free expanded graphite.

  2. Disorder-induced trapping versus Anderson localization in Bose-Einstein condensates expanding in disordered potentials

    International Nuclear Information System (INIS)

    Sanchez-Palencia, L; Clement, D; Lugan, P; Bouyer, P; Aspect, A

    2008-01-01

    We theoretically investigate the localization of an expanding Bose-Einstein condensate (BEC) with repulsive atom-atom interactions in a disordered potential. We focus on the regime where the initial inter-atomic interactions dominate over the kinetic energy and the disorder. At equilibrium in a trapping potential and for the considered small disorder, the condensate shows a Thomas-Fermi shape modified by the disorder. When the condensate is released from the trap, a strong suppression of the expansion is obtained in contrast to the situation in a periodic potential with similar characteristics. This effect crucially depends on both the momentum distribution of the expanding BEC and the strength of the disorder. For strong disorder as in the experiments reported by Clement et al 2005 Phys. Rev. Lett. 95 170409 and Fort et al 2005 Phys. Rev. Lett. 95 170410, the suppression of the expansion results from the fragmentation of the core of the condensate and from classical reflections from large modulations of the disordered potential in the tails of the condensate. We identify the corresponding disorder-induced trapping scenario for which large atom-atom interactions and strong reflections from single modulations of the disordered potential play central roles. For weak disorder, the suppression of the expansion signals the onset of Anderson localization, which is due to multiple scattering from the modulations of the disordered potential. We compute analytically the localized density profile of the condensate and show that the localization crucially depends on the correlation function of the disorder. In particular, for speckle potentials the long-range correlations induce an effective mobility edge in 1D finite systems. Numerical calculations performed in the mean-field approximation support our analysis for both strong and weak disorder

  3. Infrastructure Requirements for an Expanded Fuel Ethanol Industry

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, Robert E. [Downstream Alternatives, Inc., South Bend, IN (United States)

    2002-01-15

    This report provides technical information specifically related to ethanol transportation, distribution, and marketing issues. This report required analysis of the infrastructure requirements for an expanded ethanol industry.

  4. Biological response modifiers

    Energy Technology Data Exchange (ETDEWEB)

    Weller, R.E.

    1991-10-01

    Much of what used to be called immunotherapy is now included in the term biological response modifiers. Biological response modifiers (BRMs) are defined as those agents or approaches that modify the relationship between the tumor and host by modifying the host's biological response to tumor cells with resultant therapeutic effects.'' Most of the early work with BRMs centered around observations of spontaneous tumor regression and the association of tumor regression with concurrent bacterial infections. The BRM can modify the host response in the following ways: Increase the host's antitumor responses through augmentation and/or restoration of effector mechanisms or mediators of the host's defense or decrease the deleterious component by the host's reaction; Increase the host's defenses by the administration of natural biologics (or the synthetic derivatives thereof) as effectors or mediators of an antitumor response; Augment the host's response to modified tumor cells or vaccines, which might stimulate a greater response by the host or increase tumor-cell sensitivity to an existing response; Decrease the transformation and/or increase differentiation (maturation) of tumor cells; or Increase the ability of the host to tolerate damage by cytotoxic modalities of cancer treatment.

  5. Waste Heat-to-Power Using Scroll Expander for Organic Rankine Bottoming Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Dieckmann, John [TIAX LLC, Lexington, MA (United States); Smutzer, Chad [TIAX LLC, Lexington, MA (United States); Sinha, Jayanti [TIAX LLC, Lexington, MA (United States)

    2017-05-30

    The objective of this program was to develop a novel, scalable scroll expander for conversion of waste heat to power; this was accomplished and demonstrated in both a bench-scale system as well as a full-scale system. The expander is a key component in Organic Rankine Cycle (ORC) waste heat recovery systems which are used to convert medium-grade waste heat to electric power in a wide range of industries. These types of waste heat recovery systems allow for the capture of energy that would otherwise just be exhausted to the atmosphere. A scroll expander has the benefit over other technologies of having high efficiency over a broad range of operating conditions. The speed range of the TIAX expander (1,200 to 3,600 RPM) enables the shaft power output to directly drive an electric generator and produce 60 Hz electric power without incurring the equipment costs or losses of electronic power conversion. This greatly simplifies integration with the plant electric infrastructure. The TIAX scroll expander will reduce the size, cost, and complexity of a small-scale waste heat recovery system, while increasing the system efficiency compared to the prevailing ORC technologies at similar scale. During this project, TIAX demonstrated the scroll expander in a bench-scale test setup to have isentropic efficiency of 70-75% and operated it successfully for ~200 hours with minimal wear. This same expander was then installed in a complete ORC system driven by a medium grade waste heat source to generate 5-7 kW of electrical power. Due to funding constraints, TIAX was unable to complete this phase of testing, although the initial results were promising and demonstrated the potential of the technology.

  6. The impact of [corrected] expanded nursing practice on professional identify in Denmark.

    Science.gov (United States)

    Piil, Karin; Kolbæk, Raymond; Ottmann, Goetz; Rasmussen, Bodil

    2012-01-01

    This article explores the concept of professional identity of Danish nurses working in an expanded practice. The case study explores the experiences of a small group of Danish nurses with a new professional category that reaches into a domain that customarily belonged to physicians. The aim of this case study was to explore the impact of "nurse consultations," representing an expanded nursing role, of 5 nurses focusing on their perception of autonomy, self-esteem, and confidence. The case study used semistructured interviews with 5 participants triangulated and validated with participant observations, a focus group interview, and theoretically derived insights. This study indicates that nurses working within a new expanded professional practice see themselves as still engaged in nursing and not as substitute physicians. The study also suggests that the involved nurses gained a higher sense of autonomy, self-esteem, and confidence in their practice. These elements have a positive impact on their professional identity. The research demonstrates that for the nurses involved in expanded professional practice, the boundaries of professional practice have shifted significantly. The research indicates that an expanded practice generates a new domain within the professional identity of nurses.

  7. Alkali-silica reactivity of expanded glass granules in structure of lightweight concrete

    International Nuclear Information System (INIS)

    Bumanis, G; Bajare, D; Korjakins, A; Locs, J

    2013-01-01

    Main component in the lightweight concrete, which provides its properties, is aggregate. A lot of investigations on alkali silica reaction (ASR) between cement and lightweight aggregates have been done with their results published in the academic literature. Whereas expanded glass granules, which is relatively new product in the market of building materials, has not been a frequent research object. Therefore lightweight granules made from waste glass and eight types of cement with different chemical and mineralogical composition were examined in this research. Expanded glass granules used in this research is commercially available material produced by Penostek. Lightweight concrete mixtures were prepared by using commercial chemical additives to improve workability of concrete. The aim of the study is to identify effect of cement composition to the ASR reaction which occurs between expanded glass granules and binder. Expanded glass granules mechanical and physical properties were determined. In addition, properties of fresh and hardened concrete were determined. The ASR test was processed according to RILEM AAR-2 testing recommendation. Tests with scanning electron microscope and microstructural investigations were performed for expanded glass granules and hardened concrete specimens before and after exposing them in alkali solution

  8. Influence of Surgical Staples on Radiofrequency Ablation Using Multitined Expandable Electrodes

    International Nuclear Information System (INIS)

    Sakuhara, Yusuke; Shimizu, Tadashi; Abo, Daisuke; Hasegawa, Yu; Kato, Fumi; Kodama, Yoshihisa; Shirato, Hiroki

    2007-01-01

    Purpose. During radiofrequency ablation (RFA), there is a risk that the multitined expandable electrode will come into contact with one of the surgical staples used to treat local recurrence after surgical operations. Our objective was to evaluate whether a surgical staple would influence the RFA of egg white using a multitined expandable electrode. Methods. Multitined expandable electrodes, LeVeen needles (expandable diameter 3.0 cm), were sunk into an egg white bath with (a) no surgical staple, (b) a surgical staple touching one of the tines, or (c) a surgical staple touching two of the tines simultaneously. By connecting the LeVeen needle and copper plate at the bottom of the bath, RFA was then performed on the egg whites as a substitute for human tissue. Ten egg white baths were ablated under each of conditions (a), (b), and (c), for a total of 30 sets of coagulated egg white. Results. There was no significant difference in the time from the power-on to the roll-off (i.e., the completion and shutting off of the electric circuit) or in the maximum diameter of the thermal lesion between conditions (a) and (b) or (a) and (c). However, the minimum diameter of the thermal lesion was significantly smaller in (c) compared with (a) (p < 0.01). Conclusions. Surgical staples have the capacity to interfere with the electromagnetic field and decrease the minimum diameter of the thermal lesion in the event that a staple touches two of the tines of a multitined expandable electrode during RFA. Although the difference might be small enough to be neglected under many clinical circumstances, we recommend that, if possible, the tines not be expanded near metallic material

  9. Focusing of geodesic congruences in an accelerated expanding Universe

    International Nuclear Information System (INIS)

    Albareti, F.D.; Cembranos, J.A.R.; Cruz-Dombriz, A. de la

    2012-01-01

    We study the accelerated expansion of the Universe through its consequences on a congruence of geodesics. We make use of the Raychaudhuri equation which describes the evolution of the expansion rate for a congruence of timelike or null geodesics. In particular, we focus on the space-time geometry contribution to this equation. By straightforward calculation from the metric of a Robertson-Walker cosmological model, it follows that in an accelerated expanding Universe the space-time contribution to the Raychaudhuri equation is positive for the fundamental congruence, favoring a non-focusing of the congruence of geodesics. However, the accelerated expansion of the present Universe does not imply a tendency of the fundamental congruence to diverge. It is shown that this is in fact the case for certain congruences of timelike geodesics without vorticity. Therefore, the focusing of geodesics remains feasible in an accelerated expanding Universe. Furthermore, a negative contribution to the Raychaudhuri equation from space-time geometry which is usually interpreted as the manifestation of the attractive character of gravity is restored in an accelerated expanding Robertson-Walker space-time at high speeds

  10. Focusing of geodesic congruences in an accelerated expanding Universe

    Energy Technology Data Exchange (ETDEWEB)

    Albareti, F.D.; Cembranos, J.A.R. [Departamento de Física Teórica I, Universidad Complutense de Madrid, Ciudad Universitaria, E-28040 Madrid (Spain); Cruz-Dombriz, A. de la, E-mail: fdalbareti@estumail.ucm.es, E-mail: cembra@fis.ucm.es, E-mail: alvaro.delacruz-dombriz@uct.ac.za [Astrophysics, Cosmology and Gravity Centre (ACGC), University of Cape Town, 7701 Rondebosch, Cape Town (South Africa)

    2012-12-01

    We study the accelerated expansion of the Universe through its consequences on a congruence of geodesics. We make use of the Raychaudhuri equation which describes the evolution of the expansion rate for a congruence of timelike or null geodesics. In particular, we focus on the space-time geometry contribution to this equation. By straightforward calculation from the metric of a Robertson-Walker cosmological model, it follows that in an accelerated expanding Universe the space-time contribution to the Raychaudhuri equation is positive for the fundamental congruence, favoring a non-focusing of the congruence of geodesics. However, the accelerated expansion of the present Universe does not imply a tendency of the fundamental congruence to diverge. It is shown that this is in fact the case for certain congruences of timelike geodesics without vorticity. Therefore, the focusing of geodesics remains feasible in an accelerated expanding Universe. Furthermore, a negative contribution to the Raychaudhuri equation from space-time geometry which is usually interpreted as the manifestation of the attractive character of gravity is restored in an accelerated expanding Robertson-Walker space-time at high speeds.

  11. Expandable metallic stents for tracheobronchial stenoses in esophageal cancer.

    Science.gov (United States)

    Takamori, S; Fujita, H; Hayashi, A; Tayama, K; Mitsuoka, M; Ohtsuka, S; Shirouzu, K

    1996-09-01

    Tracheobronchial stenosis in patients with esophageal cancer can be life threatening. Few reports have discussed use of expandable metallic stents for central airway stenoses in patients with esophageal cancer. Twelve patients with esophageal cancer underwent placement of expandable metallic stents for respiratory distress caused by tracheobronchial stricture. Single or double metallic stents were placed in the stenotic airways under fluoroscopic guidance. Improvement in respiratory symptoms and clinical outcome were assessed. Most stenoses were located in the trachea or the left main bronchus. From one to four expandable metallic stents were placed in each stricture site, with immediate relief of respiratory symptoms in 8 patients. One patient with tracheomalacia in alive 3 years after stent placement and another is alive 6 months after stent insertion. The other 10 patients lived from 10 to 70 days (mean; survival, 35 days) after stent placement. Death was due to progression of disease. Although metallic stents are useful for relieving respiratory distress in patients with advanced esophageal cancer, additional therapies should be considered.

  12. Modified Allergens for Immunotherapy.

    Science.gov (United States)

    Satitsuksanoa, Pattraporn; Głobińska, Anna; Jansen, Kirstin; van de Veen, Willem; Akdis, Mübeccel

    2018-02-16

    During the past few decades, modified allergens have been developed for use in allergen-specific immunotherapy (AIT) with the aim to improve efficacy and reduce adverse effects. This review aims to provide an overview of the different types of modified allergens, their mechanism of action and their potential for improving AIT. In-depth research in the field of allergen modifications as well as the advance of recombinant DNA technology have paved the way for improved diagnosis and research on human allergic diseases. A wide range of structurally modified allergens has been generated including allergen peptides, chemically altered allergoids, adjuvant-coupled allergens, and nanoparticle-based allergy vaccines. These modified allergens show promise for the development of AIT regimens with improved safety and long-term efficacy. Certain modifications ensure reduced IgE reactivity and retained T cell reactivity, which facilities induction of immune tolerance to the allergen. To date, multiple clinical trials have been performed using modified allergens. Promising results were obtained for the modified cat, grass and birch pollen, and house dust mite allergens. The use of modified allergens holds promise for improving AIT efficacy and safety. There is however a need for larger clinical studies to reliably assess the added benefit for the patient of using modified allergens for AIT.

  13. Photon beam dose distributions for patients with implanted temporary tissue expanders

    Science.gov (United States)

    Asena, A.; Kairn, T.; Crowe, S. B.; Trapp, J. V.

    2015-01-01

    This study examines the effects of temporary tissue expanders (TTEs) on the dose distributions of photon beams in breast cancer radiotherapy treatments. EBT2 radiochromic film and ion chamber measurements were taken to quantify the attenuation and backscatter effects of the inhomogeneity. Results illustrate that the internal magnetic port present in a tissue expander causes a dose reduction of approximately 25% in photon tangent fields immediately downstream of the implant. It was also shown that the silicone elastomer shell of the tissue expander reduced the dose to the target volume by as much as 8%. This work demonstrates the importance for an accurately modelled high-density implant in the treatment planning system for post-mastectomy breast cancer patients.

  14. Esophageal carcinoma treatment with self-expanding covered stent implanted in esophagus

    International Nuclear Information System (INIS)

    Liu Mingguo; Ji Yan; He Nengwei

    2006-01-01

    Objective: To investigate the clinical significance of the treatment to esophageal cancer by self- expanding covered stent implanted into esophagus. Methods: Under fluoroscopic guidance and with guidance wire , 20 self-expanding covered stents were implanted into stenotic part of esophagus to recanalize the esophagus, then follow up to observe the clinical symptom improved. Results: Technical success was obtained 20 cases without any complication. Clinical symptom were improved in shot time. Conclusions: self-expanding covered stent is implanted in stenotic part of esophageal carcinoma to treat esophageal stenosis and enable to improved clinical symptom in shot time, if combined with transcatheter arterial infusion and embolization, Radiotherapy, Chinese medical treatment, it enable to lengthen life time remarkably. (authors)

  15. Structural and magnetic properties of {open_quotes}expanded{close_quotes} Mn

    Energy Technology Data Exchange (ETDEWEB)

    Grigorov, I.L.; Walker, J.C. [Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland21218 (United States); Hawley, M.E.; Brown, G.W. [Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico87545 (United States); Luett, M.; Fitzsimmons, M.R. [Manuel Lujan Jr. Neutron Scattering Center, Los Alamos National Laboratory, Los Alamos, New Mexico87545 (United States)

    1998-06-01

    Structural and magnetic properties of {open_quotes}expanded{close_quotes} Mn deposited on (111) oriented fcc noble metals were studied with single-crystal x-ray diffraction and exchange bias measurements. A single peak corresponding to this phase was found at momentum transfer q=2.86{Angstrom}{sup {minus}1} along six equivalent [11{bar 2}] directions of the noble metal substrate. Magnetic hysteresis of the field cooled Fe/Mn bilayers exhibited a characteristic shift along the field axis, indicating antiferromagnetic order in the expanded Mn with T{sub N}{ge}20K. The magnetic and structural data are consistent with understanding the expanded phase as trigonally distorted {alpha}-Mn. {copyright} {ital 1998 American Institute of Physics.}

  16. Gravitational instability in a multicomponent expanding medium

    International Nuclear Information System (INIS)

    Solov'eva, L.V.; Nurgaliev, I.S.

    1985-01-01

    In the Newtonian approximation we consider the gravitational instability of a two- or N-component medium in an expanding universe. The system of density-perturbation equations is solved in the short- and long-wave limits. For small values of the wave vector k, a result obtained for the stationary case continues to hold true: at most there can exist only one unstable mode. If k is kept fixed, the introduction of a perturbation component delta/sub i/ will speed the growth of fluctuations delta/sub j/, provided the adiabatic indices γ/sub i/>γ/sub j/. In the large-k limit, ordinary acoustic waves result. Other components will begin to manifest themselves in the first-order terms when the oscillation amplitude is expanded in powers of k -1 : provided γ/sub j/>γ/sub i/> or =4/3, the ith-component amplitude will decay more slowly than otherwise

  17. Preparation of C-terminally modified chemokines by expressed protein ligation.

    Science.gov (United States)

    Baumann, Lars; Steinhagen, Max; Beck-Sickinger, Annette G

    2013-01-01

    In order to link structural features on a molecular level to the function of chemokines, site-specific modification strategies are strongly required. These can be used to incorporate fluorescent dyes and/or physical probes to allow investigations in a wide range of biological and physical techniques, e.g., nuclear magnetic resonance (NMR) spectroscopy, fluorescence microscopy, fluorescence resonance energy transfer (FRET), or fluorescence correlation spectroscopy (FCS). Only a limited number of functional groups within the 20 canonical amino acids allow ligation strategies that can be helpful to introduce novel functionalities, which in turn expand the scope of chemoselective and orthogonal reactivity of (semi)synthetic chemokines. In the present chapter we mainly focus on the fabulous history of native chemical ligation (NCL) and provide a general protocol for the preparation of C-terminally modified SDF-1α including tips and tricks for practical work. We believe that this protocol can be easily adapted to other chemokines and many proteins in general.

  18. Modified Van der Waals equation and law of corresponding states

    Science.gov (United States)

    Zhong, Wei; Xiao, Changming; Zhu, Yongkai

    2017-04-01

    It is well known that the Van der Waals equation is a modification of the ideal gas law, yet it can be used to describe both gas and liquid, and some important messages can be obtained from this state equation. However, the Van der Waals equation is not a precise state equation, and it does not give a good description of the law of corresponding states. In this paper, we expand the Van der Waals equation into its Taylor's series form, and then modify the fourth order expansion by changing the constant Virial coefficients into their analogous ones. Via this way, a more precise result about the law of corresponding states has been obtained, and the law of corresponding states can then be expressed as: in terms of the reduced variables, all fluids should obey the same equation with the analogous Virial coefficients. In addition, the system of 3 He with quantum effects has also been taken into consideration with our modified Van der Waals equation, and it is found that, for a normal system without quantum effect, the modification on ideal gas law from the Van der Waals equation is more significant than the real case, however, for a system with quantum effect, this modification is less significant than the real case, thus a factor is introduced in this paper to weaken or strengthen the modification of the Van der Waals equation, respectively.

  19. Prevalence and correlates of posttrauma distorted beliefs: evaluating DSM-5 PTSD expanded cognitive symptoms in a national sample.

    Science.gov (United States)

    Cox, Keith S; Resnick, Heidi S; Kilpatrick, Dean G

    2014-06-01

    The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5; American Psychiatric Association [APA], 2013) modified the diagnostic criteria for posttraumatic stress disorder (PTSD), including expanding the scope of dysfunctional, posttrauma changes in belief (symptoms D2-persistent negative beliefs and expectations about oneself or the world, and D3-persistent distorted blame of self or others for the cause or consequences of the traumatic event). D2 and D3 were investigated using a national sample of U.S. adults (N = 2,498) recruited from an online panel. The prevalence of D2 and D3 was substantially higher among those with lifetime PTSD than among trauma-exposed individuals without lifetime PTSD (D2: 74.6% vs 23.9%; D3: 80.6% vs 35.7%). In multivariate analyses, the strongest associates of D2 were interpersonal assault (OR = 2.39), witnessing interpersonal assault (OR = 1.63), gender (female, OR = 2.11), and number of reported traumatic events (OR = 1.88). The strongest correlates of D3 were interpersonal assault (OR = 3.08), witnessing interpersonal assault (OR = 1.57), gender (female, OR = 2.30), and number of reported traumatic events (OR = 1.91). The findings suggested the expanded cognitive symptoms in the DSM-5 diagnostic criteria better capture the cognitive complexity of PTSD than those of the DSM-IV. Copyright © 2014 International Society for Traumatic Stress Studies.

  20. Long-term implications of observing an expanding cosmological civilization

    Science.gov (United States)

    Olson, S. Jay

    2018-01-01

    Suppose that advanced civilizations, separated by a cosmological distance and time, wish to maximize their access to cosmic resources by rapidly expanding into the universe. How does the presence of one limit the expansionistic ambitions of another, and what sort of boundary forms between their expanding domains? We describe a general scenario for any expansion speed, separation distance and time. We then specialize to a question of particular interest: What are the future prospects for a young and ambitious civilization if they can observe the presence of another at a cosmological distance? We treat cases involving the observation of one or two expanding domains. In the single-observation case, we find that almost any plausible detection will limit one's future cosmic expansion to some extent. Also, practical technological limits to expansion speed (well below the speed of light) play an interesting role. If a domain is visible at the time one embarks on cosmic expansion, higher practical limits to expansion speed are beneficial only up to a certain point. Beyond this point, a higher speed limit means that gains in the ability to expand are more than offset by the first-mover advantage of the observed domain. In the case of two visible domains, it is possible to be `trapped' by them if the practical speed limit is high enough and their angular separation in the sky is large enough, i.e. one's expansion in any direction will terminate at a boundary with the two visible civilizations. Detection at an extreme cosmological distance has surprisingly little mitigating effect on our conclusions.

  1. Successful range-expanding plants experience less above-ground and below-ground enemy impact.

    Science.gov (United States)

    Engelkes, Tim; Morriën, Elly; Verhoeven, Koen J F; Bezemer, T Martijn; Biere, Arjen; Harvey, Jeffrey A; McIntyre, Lauren M; Tamis, Wil L M; van der Putten, Wim H

    2008-12-18

    Many species are currently moving to higher latitudes and altitudes. However, little is known about the factors that influence the future performance of range-expanding species in their new habitats. Here we show that range-expanding plant species from a riverine area were better defended against shoot and root enemies than were related native plant species growing in the same area. We grew fifteen plant species with and without non-coevolved polyphagous locusts and cosmopolitan, polyphagous aphids. Contrary to our expectations, the locusts performed more poorly on the range-expanding plant species than on the congeneric native plant species, whereas the aphids showed no difference. The shoot herbivores reduced the biomass of the native plants more than they did that of the congeneric range expanders. Also, the range-expanding plants developed fewer pathogenic effects in their root-zone soil than did the related native species. Current predictions forecast biodiversity loss due to limitations in the ability of species to adjust to climate warming conditions in their range. Our results strongly suggest that the plants that shift ranges towards higher latitudes and altitudes may include potential invaders, as the successful range expanders may experience less control by above-ground or below-ground enemies than the natives.

  2. Lattice expansion of carbon-stabilized expanded austenite

    DEFF Research Database (Denmark)

    Hummelshøj, Thomas Strabo; Christiansen, Thomas; Somers, Marcel A. J.

    2010-01-01

    The lattice parameter of expanded austenite was determined as a function of the content of interstitially dissolved carbon in homogeneous, carburized thin stainless steel foils. For the first time this expansion of the face-centered cubic lattice is determined on unstrained austenite. It is found...

  3. Technical Note: Effect of Incorporating Expanded Polystyrene ...

    African Journals Online (AJOL)

    Incorporating expanded polystyrene granules in concrete matrix can produce lightweight polystyrene aggregate concrete of various densities. Workability which is an important property of concrete, aects the rate of placement and the degree of compaction of concrete. Inadequate compaction leads to reduction in both ...

  4. Expanding Sex-Role Definitions by Self-Discovery.

    Science.gov (United States)

    Kahn, Sharon E.; Greenberg, Leslie S.

    1980-01-01

    Counselors who stimulate client self-discovery may help these clients experience undeveloped parts of themselves and expand their definitions of themselves and their sex-role possibilities. Stimulation methods actively involve clients in the exploration of sex-role concerns to change restrictive self-concepts. (Author)

  5. Expanding CEP290 mutational spectrum in ciliopathies

    NARCIS (Netherlands)

    Travaglini, Lorena; Brancati, Francesco; Attie-Bitach, Tania; Audollent, Sophie; Bertini, Enrico; Kaplan, Josseline; Perrault, Isabelle; Iannicelli, Miriam; Mancuso, Brunella; Rigoli, Luciana; Rozet, Jean-Michel; Swistun, Dominika; Tolentino, Jerlyn; Dallapiccola, Bruno; Gleeson, Joseph G.; Valente, Enza Maria; Zankl, A.; Leventer, R.; Grattan-Smith, P.; Janecke, A.; D'Hooghe, M.; Sznajer, Y.; van Coster, R.; Demerleir, L.; Dias, K.; Moco, C.; Moreira, A.; Kim, C. Ae; Maegawa, G.; Petkovic, D.; Abdel-Salam, G. M. H.; Abdel-Aleem, A.; Zaki, M. S.; Marti, I.; Quijano-Roy, S.; Sigaudy, S.; de Lonlay, P.; Romano, S.; Touraine, R.; Koenig, M.; Lagier-Tourenne, C.; Messer, J.; Collignon, P.; Wolf, N.; Philippi, H.; Kitsiou Tzeli, S.; Halldorsson, S.; Johannsdottir, J.; Ludvigsson, P.; Phadke, S. R.; Udani, V.; Stuart, B.; Magee, A.; Lev, D.; Michelson, M.; Ben-Zeev, B.; Fischetto, R.; Benedicenti, F.; Stanzial, F.; Borgatti, R.; Accorsi, P.; Battaglia, S.; Fazzi, E.; Giordano, L.; Pinelli, L.; Boccone, L.; Bigoni, S.; Ferlini, A.; Donati, M. A.; Caridi, G.; Divizia, M. T.; Faravelli, F.; Ghiggeri, G.; Pessagno, A.; Briguglio, M.; Briuglia, S.; Salpietro, C. D.; Tortorella, G.; Adami, A.; Castorina, P.; Lalatta, F.; Marra, G.; Riva, D.; Scelsa, B.; Spaccini, L.; Uziel, G.; del Giudice, E.; Laverda, A. M.; Ludwig, K.; Permunian, A.; Suppiej, A.; Signorini, S.; Uggetti, C.; Battini, R.; Di Giacomo, M.; Cilio, M. R.; Di Sabato, M. L.; Leuzzi, V.; Parisi, P.; Pollazzon, M.; Silengo, M.; de Vescovi, R.; Greco, D.; Romano, C.; Cazzagon, M.; Simonati, A.; Al-Tawari, A. A.; Bastaki, L.; Mégarbané, A.; Sabolic Avramovska, V.; de Jong, M. M.; Stromme, P.; Koul, R.; Rajab, A.; Azam, M.; Barbot, C.; Martorell Sampol, L.; Rodriguez, B.; Pascual-Castroviejo, I.; Teber, S.; Anlar, B.; Comu, S.; Karaca, E.; Kayserili, H.; Yüksel, A.; Akcakus, M.; Al Gazali, L.; Sztriha, L.; Nicholl, D.; Woods, C. G.; Bennett, C.; Hurst, J.; Sheridan, E.; Barnicoat, A.; Hennekam, R.; Lees, M.; Blair, E.; Bernes, S.; Sanchez, H.; Clark, A. E.; DeMarco, E.; Donahue, C.; Sherr, E.; Hahn, J.; Sanger, T. D.; Gallager, T. E.; Dobyns, W. B.; Daugherty, C.; Krishnamoorthy, K. S.; Sarco, D.; Walsh, C. A.; McKanna, T.; Milisa, J.; Chung, W. K.; de Vivo, D. C.; Raynes, H.; Schubert, R.; Seward, A.; Brooks, D. G.; Goldstein, A.; Caldwell, J.; Finsecke, E.; Maria, B. L.; Holden, K.; Cruse, R. P.; Swoboda, K. J.; Viskochil, D.

    2009-01-01

    Ciliopathies are an expanding group of rare conditions characterized by multiorgan involvement, that are caused by mutations in genes encoding for proteins of the primary cilium or its apparatus. Among these genes, CEP290 bears an intriguing allelic spectrum, being commonly mutated in Joubert

  6. Fiber-optic coupling based on nonimaging expanded-beam optics.

    Science.gov (United States)

    Moslehi, B; Ng, J; Kasimoff, I; Jannson, T

    1989-12-01

    We have fabricated and experimentally tested low-cost and mass-producible multimode fiber-optic couplers and connectors based on nonimaging beam-expanding optics and Liouville's theorem. Analysis indicates that a pair coupling loss of -0.25 dB can be achieved. Experimentally, we measured insertion losses as low as -0.38 dB. The beam expanders can be mass produced owing to the use of plastic injection-molding fabrication techniques and packaged in standard connector housings. This design is compatible with the fiber geometry and can yield highly stable coupling owing to its high tolerance for misalignments.

  7. Scalar-Tensor Black Holes Embedded in an Expanding Universe

    Science.gov (United States)

    Tretyakova, Daria; Latosh, Boris

    2018-02-01

    In this review we focus our attention on scalar-tensor gravity models and their empirical verification in terms of black hole and wormhole physics. We focus on a black hole, embedded in an expanding universe, describing both cosmological and astrophysical scales. We show that in scalar-tensor gravity it is quite common that the local geometry is isolated from the cosmological expansion, so that it does not backreact on the black hole metric. We try to extract common features of scalar-tensor black holes in an expanding universe and point out the gaps that must be filled.

  8. Scalar-Tensor Black Holes Embedded in an Expanding Universe

    Directory of Open Access Journals (Sweden)

    Daria Tretyakova

    2018-02-01

    Full Text Available In this review, we focus our attention on scalar-tensor gravity models and their empirical verification in terms of black hole and wormhole physics. We focus on black holes, embedded in an expanding universe, describing both cosmological and astrophysical scales. We show that in scalar-tensor gravity it is quite common that the local geometry is isolated from the cosmological expansion, so that it does not backreact on the black hole metric. We try to extract common features of scalar-tensor black holes in an expanding universe and point out the issues that are not fully investigated.

  9. Expanding Agricultural and Rural Extension Roles for Sustainable ...

    African Journals Online (AJOL)

    Expanding Agricultural and Rural Extension Roles for Sustainable Extension ... privatization of the public sector of national economies of developing nations has ... include marketing extension, non-farm rural micro enterprise development, ...

  10. Evaluation of external heat loss from a small-scale expander used in organic Rankine cycle

    International Nuclear Information System (INIS)

    Li Jing; Pei Gang; Li Yunzhu; Ji Jie

    2011-01-01

    With the scaling down of the Organic Rankine Cycle (ORC), the engine shaft power is not only determined by the enthalpy drop in the expansion process but also the external heat loss from the expander. Theoretical and experimental support in evaluating small-scale expander heat loss is rare. This paper presents a quantitative study on the convection, radiation, and conduction heat transfer from a kW-scale expander. A mathematical model is built and validated. The results show that the external radiative or convective heat loss coefficient was about 3.2 or 7.0 W/K.m 2 when the ORC operated around 100 o C. Radiative and convective heat loss coefficients increased as the expander operation temperature increased. Conductive heat loss due to the connection between the expander and the support accounted for a large proportion of the total heat loss. The fitting relationships between heat loss and mean temperature difference were established. It is suggested that low conductivity material be embodied in the support of expander. Mattress insulation for compact expander could be eliminated when the operation temperature is around 100 o C. - Highlights: → A close examination of external heat loss from a small expander is presented. → Theoretical analysis and experimental test were conducted. → The established formulas can be applied to other small ORC expanders. → The results are useful in further research of small-scale ORC.

  11. Does partial expander deflation exacerbate the adverse effects of radiotherapy in two-stage breast reconstruction?

    Science.gov (United States)

    Celet Ozden, Burcu; Guven, Erdem; Aslay, Isik; Kemikler, Gonul; Olgac, Vakur; Soluk Tekkesin, Merva; Serarslan, Bengul; Tumerdem Ulug, Burcak; Bilgin Karabulut, Aylin; Arinci, Atilla; Emekli, Ufuk

    2012-02-20

    The optimum protocol for expander volume adjustment with respect to the timing and application of radiotherapy remains controversial. Eighteen New Zealand rabbits were divided into three groups. Metallic port integrated anatomic breast expanders of 250 cc were implanted on the back of each animal and controlled expansion was performed. Group I underwent radiotherapy with full expanders while in Group II, expanders were partially deflated immediately prior to radiotherapy. Control group did not receive radiotherapy.The changes in blood flow at different volume adjustments were investigated in Group II by laser Doppler flowmetry. Variations in the histopathologic properties of the irradiated tissues including the skin, capsule and the pocket floor, were compared in the biopsy specimens taken from different locations in each group. A significant increase in skin blood flow was detected in Group II with partial expander deflation. Overall, histopathologic exam revealed aggravated findings of chronic radiodermatitis (epidermal atrophy, dermal inflammation and fibrosis, neovascularisation and vascular changes as well as increased capsule thickness) especially around the lower expander pole, in Group II. Expander deflation immediately prior to radiotherapy, may augment the adverse effects, especially in the lower expander pole, possibly via enhanced radiosensitization due to a relative increase in the blood flow and tissue oxygenation.

  12. Does partial expander deflation exacerbate the adverse effects of radiotherapy in two-stage breast reconstruction?

    Directory of Open Access Journals (Sweden)

    Celet Ozden Burcu

    2012-02-01

    Full Text Available Abstract Background The optimum protocol for expander volume adjustment with respect to the timing and application of radiotherapy remains controversial. Methods Eighteen New Zealand rabbits were divided into three groups. Metallic port integrated anatomic breast expanders of 250 cc were implanted on the back of each animal and controlled expansion was performed. Group I underwent radiotherapy with full expanders while in Group II, expanders were partially deflated immediately prior to radiotherapy. Control group did not receive radiotherapy. The changes in blood flow at different volume adjustments were investigated in Group II by laser Doppler flowmetry. Variations in the histopathologic properties of the irradiated tissues including the skin, capsule and the pocket floor, were compared in the biopsy specimens taken from different locations in each group. Results A significant increase in skin blood flow was detected in Group II with partial expander deflation. Overall, histopathologic exam revealed aggravated findings of chronic radiodermatitis (epidermal atrophy, dermal inflammation and fibrosis, neovascularisation and vascular changes as well as increased capsule thickness especially around the lower expander pole, in Group II. Conclusions Expander deflation immediately prior to radiotherapy, may augment the adverse effects, especially in the lower expander pole, possibly via enhanced radiosensitization due to a relative increase in the blood flow and tissue oxygenation.

  13. Hybrid Scenarios, Transmedia Storytelling, Expanded Ethnography

    Directory of Open Access Journals (Sweden)

    Daniel Domínguez Figaredo

    2012-10-01

    Full Text Available The transformation of social scenarios due to the impact of digital technologies, introduces new possibilities for ethnographic research. Once the initial approaches focused on the dichotomy of “physical-virtual spaces” have been overcame, it comes a stage of maturity that allows the ethnographers to open new avenues for conceptual and analytical methodology applied in techno-social scenarios. This article discusses the evolution of some key dimensions of ethnography according to the new social and epistemological framework. The discussion is based on the analysis of expanded practices that take place in the new techno-social spaces, defined as hybrid environments, where technologies are embedded in the physical life of the subjects. On the one hand, we consider the production of actions based on the assembly of ideas, meanings and objects through digital mediation devices. It is also analysed the transmedia component of the narratives that make sense to allow the experiments. Underlying the analysis, some elements are introduced for discussion on the scope of expanded ethnographic research, the influence of transmedia phenomenon in the notion of “field” and the methods for determining the significance through digital storytelling.

  14. Bank Directors’ Perceptions of Expanded Auditor's Reports

    DEFF Research Database (Denmark)

    Boolaky, Pran Krishansing; Quick, Reiner

    2016-01-01

    Subsequent to the financial crisis, standard setters developed suggestions for enhancing the audit function, in order to increase financial stability. One related idea is to expand the audit report disclosed to the public, to ensure that it is fit for purpose. This study investigates the impact o...

  15. Fish DNA-modified clays: Towards highly flame retardant polymer nanocomposite with improved interfacial and mechanical performance

    Science.gov (United States)

    Zabihi, Omid; Ahmadi, Mojtaba; Khayyam, Hamid; Naebe, Minoo

    2016-12-01

    Deoxyribonucleic Acid (DNA) has been recently found to be an efficient renewable and environmentally-friendly flame retardant. In this work, for the first time, we have used waste DNA from fishing industry to modify clay structure in order to increase the clay interactions with epoxy resin and take benefit of its additional thermal property effect on thermo-physical properties of epoxy-clay nanocomposites. Intercalation of DNA within the clay layers was accomplished in a one-step approach confirmed by FT-IR, XPS, TGA, and XRD analyses, indicating that d-space of clay layers was expanded from ~1.2 nm for pristine clay to ~1.9 nm for clay modified with DNA (d-clay). Compared to epoxy nanocomposite containing 2.5%wt of Nanomer I.28E organoclay (m-clay), it was found that at 2.5%wt d-clay loading, significant enhancements of ~14%, ~6% and ~26% in tensile strength, tensile modulus, and fracture toughness of epoxy nanocomposite can be achieved, respectively. Effect of DNA as clay modifier on thermal performance of epoxy nanocomposite containing 2.5%wt d-clay was evaluated using TGA and cone calorimetry analysis, revealing significant decreases of ~4000 kJ/m2 and ~78 kW/m2 in total heat release and peak of heat release rate, respectively, in comparison to that containing 2.5%wt of m-clay.

  16. Parameter Sensitivity Study for Typical Expander-Based Transcritical CO2 Refrigeration Cycles

    Directory of Open Access Journals (Sweden)

    Bo Zhang

    2018-05-01

    Full Text Available A sensitivity study was conducted for three typical expander-based transcritical CO2 cycles with the developed simulation model, and the sensitivities of the maximum coefficient of performance (COP to the key operating parameters, including the inlet pressure of gas cooler, the temperatures at evaporator inlet and gas cooler outlet, the inter-stage pressure and the isentropic efficiency of expander, were obtained. The results showed that the sensitivity to the gas cooler inlet pressure differs greatly before and after the optimal gas cooler inlet pressure. The sensitivity to the intercooler outlet temperature in the two-stage cycles increases sharply to near zero and then keeps almost constant at intercooler outlet temperature of higher than 45 °C. However, the sensitivity stabilizes near zero when the evaporator inlet temperature is very low of −26.1 °C. In two-stage compression with an intercooler and an expander assisting in driving the first-stage compressor (TEADFC cycle, an abrupt change in the sensitivity of maximum COP to the inter-stage pressure was observed, but disappeared after intercooler outlet temperature exceeds 50 °C. The sensitivity of maximum COP to the expander isentropic efficiency increases almost linearly with the expander isentropic efficiency.

  17. Construction and Analysis of a Novel 2-D Optical Orthogonal Codes Based on Modified One-coincidence Sequence

    Science.gov (United States)

    Ji, Jianhua; Wang, Yanfen; Wang, Ke; Xu, Ming; Zhang, Zhipeng; Yang, Shuwen

    2013-09-01

    A new two-dimensional OOC (optical orthogonal codes) named PC/MOCS is constructed, using PC (prime code) for time spreading and MOCS (modified one-coincidence sequence) for wavelength hopping. Compared with PC/PC, the number of wavelengths for PC/MOCS is not limited to a prime number. Compared with PC/OCS, the length of MOCS need not be expanded to the same length of PC. PC/MOCS can be constructed flexibly, and also can use available wavelengths effectively. Theoretical analysis shows that PC/MOCS can reduce the bit error rate (BER) of OCDMA system, and can support more users than PC/PC and PC/OCS.

  18. On Modified Bar recursion

    DEFF Research Database (Denmark)

    Oliva, Paulo Borges

    2002-01-01

    Modified bar recursion is a variant of Spector's bar recursion which can be used to give a realizability interpretation of the classical axiom of dependent choice. This realizability allows for the extraction of witnesses from proofs of forall-exists-formulas in classical analysis. In this talk I...... shall report on results regarding the relationship between modified and Spector's bar recursion. I shall also show that a seemingly weak form of modified bar recursion is as strong as "full" modified bar recursion in higher types....

  19. GWDC Expands High-End Market Share

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ It is a decision of great significance for GWDC to expand high-end market share in order to realize its transformation of development strategy and improve its development quality. As an important step of GWDC to explore high-end market, Oman PDO Project marks the first time that the Chinese petroleum engineering service team cooperates with the transnational petroleum corporations ranking first three in the world.

  20. Expanding the Visibility of Women's Work: Policy Implications.

    Science.gov (United States)

    Messias, DeAnne K. Hilfinger; Regev, Hanna; Im, Eun-Ok; Spiers, Judith A.; Van, Paulina; Meleis, Afaf Ibrahim

    1997-01-01

    Social conceptualization and media images of women's work affect health and social policy formation. Nurses can expand the visibility of women's work and promote gender-sensitive policies within and outside the profession. (SK)

  1. The expanding plasma jet

    International Nuclear Information System (INIS)

    Sanden, M.C.M. van den.

    1991-01-01

    This thesis concerns the fundamental aspects of an argon plasma expanding from a cascaded arc. This type of plasma is not only used for fundamental research but also for technologically orientated research on plasma deposition and plasma sources. The important characteristics of the plasma are a strong supersonic expansion in which the neutral particle and ion densities decrease three orders of magnitude, followed by a stationary shock front. After the shock front the plasma expands further subsonically. A part of this thesis is devoted to the discussion of a newly constructed combined Thomson-Rayleigh scattering set up. With this set up the electron density, the electron temperature and the neutral particle density are measured locally in the plasma for different conditions. In the analysis of the measured spectra weak coherent effects and the measured apparatus profile are included. The inaccuracies are small, ranging from 1 to 4 percent for the electron density and 2 to 6 percent for the electron temperature, depending on the plasma conditions. The inaccuracy of the neutral particle density determination is larger and ranges from 10 to 50 percent. The detection limits for the electron and neutral particle density are 7.10 17 m -3 and 1.10 20 m -3 respectively. A side path in this thesis is the derivation of the Saha equation for a two-temperature plasma. The reason for this derivation was the dispute in the literature about the correct form of this equation. In this thesis it is shown, from the correct extension of the second law of thermodynamics and from the non-equilibrium formalism of Zubarev, That in the limit of m e /m h ->0 the generalized Saha equation depends on the electron temperature only. (author). 221 refs.; 54 figs.; 13 tabs

  2. Circle diffeomorphisms forced by expanding circle maps

    NARCIS (Netherlands)

    Homburg, A.J.

    2012-01-01

    We discuss the dynamics of skew product maps defined by circle diffeomorphisms forced by expanding circle maps. We construct an open class of such systems that are robustly topologically mixing and for which almost all points in the same fiber converge under iteration. This property follows from the

  3. Quantifying the impact of expanded age group campaigns for polio eradication.

    Science.gov (United States)

    Wagner, Bradley G; Behrend, Matthew R; Klein, Daniel J; Upfill-Brown, Alexander M; Eckhoff, Philip A; Hu, Hao

    2014-01-01

    A priority of the Global Polio Eradication Initiative (GPEI) 2013-2018 strategic plan is to evaluate the potential impact on polio eradication resulting from expanding one or more Supplementary Immunization Activities (SIAs) to children beyond age five-years in polio endemic countries. It has been hypothesized that such expanded age group (EAG) campaigns could accelerate polio eradication by eliminating immunity gaps in older children that may have resulted from past periods of low vaccination coverage. Using an individual-based mathematical model, we quantified the impact of EAG campaigns in terms of probability of elimination, reduction in polio transmission and age stratified immunity levels. The model was specifically calibrated to seroprevalence data from a polio-endemic region: Zaria, Nigeria. We compared the impact of EAG campaigns, which depend only on age, to more targeted interventions which focus on reaching missed populations. We found that EAG campaigns would not significantly improve prospects for polio eradication; the probability of elimination increased by 8% (from 24% at baseline to 32%) when expanding three annual SIAs to 5-14 year old children and by 18% when expanding all six annual SIAs. In contrast, expanding only two of the annual SIAs to target hard-to-reach populations at modest vaccination coverage-representing less than one tenth of additional vaccinations required for the six SIA EAG scenario-increased the probability of elimination by 55%. Implementation of EAG campaigns in polio endemic regions would not improve prospects for eradication. In endemic areas, vaccination campaigns which do not target missed populations will not benefit polio eradication efforts.

  4. Subclinical leaflet thickening and stent frame geometry in self-expanding transcatheter heart valves

    DEFF Research Database (Denmark)

    Fuchs, Andreas; De Backer, Ole; Brooks, Matthew

    2017-01-01

    AIMS: This study aimed to assess the potential relationship between subclinical leaflet thickening and stent frame geometry in patients who underwent aortic valve replacement with a self-expanding transcatheter heart valve (THV). METHODS AND RESULTS: Seventy-five patients with a self-expanding THV....... CONCLUSIONS: Regional THV stent frame underexpansion is associated with an increased risk of leaflet thickening. Post-dilatation of self-expanding THV as well as a supra-annular valve position seem to reduce the occurrence of this phenomenon....

  5. Esophagojejunal anastomotic leak managed with self expandable metallic stent

    Directory of Open Access Journals (Sweden)

    Arvind Madurandagam Annapillai

    2013-01-01

    Full Text Available Esophagealjejunal anastomotic leak after gastrectomy is a serious surgical emergency with high mortality. This report describes a 57-year-old male with esophagojejunal anastomotic leak following total gastrectomy for gastric cancer and was managed successfully with self-expandable metallic stent. To our knowledge this is the first such report from India. This case report highlights the need of interdisciplinary coordination in managing this difficult clinical situation. Endotherapy with self-expandable metallic stent (SEM provided twin benefits of improving respiratory embarrassment and the joy of eating. Therapy of such difficult cases must be individualized; however, and SEM stent usage is a viable option

  6. Dissipation and fluctuation of quantum fields in expanding universes

    International Nuclear Information System (INIS)

    Morikawa, M.

    1990-01-01

    A stochastic dynamics of a long-wavelength part of a scalar field in an expanding universe is derived by using the influence functional method. Dissipation as well as fluctuation are derived for general parameters: a mass, a coupling to the scalar curvature, and a cutoff scale parameter. A dissipation-fluctuation relation is found with a temperature which is proportional to the Hawking temperature, but system dependent. The method is further applied to an expanding universe with a power law and yields the dispersion which agrees with that obtained by the regularization method. The back reaction to the background de Sitter space itself is also obtained

  7. Expanding Business Opportunities for African Youth in Agricultural ...

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

    Expanding Business Opportunities for African Youth in Agricultural Value ... sector actors who can help commercialize them and achieve large-scale impacts. ... CultiAF supports research to achieve long-term food security in Eastern and ...

  8. Overview of the APT high-energy beam transport and beam expanders

    International Nuclear Information System (INIS)

    Shafer, R.E.; Blind, B.; Gray, E.R.

    1997-01-01

    The APT high energy beam transport (HEBT) and beam expanders convey the 1700-MeV, 100-mA cw proton beam from the linac to the tritium target/blanket assembly, or a tuning beam stop. The HEBT includes extensive beam diagnostics, collimators, and beam jitter correction, to monitor and control the 170-MW beam prior to expansion. A zero-degree beamline conveys the beam to the beam stop, and an achromatic bend conveys the beam to the tritium production target. Nonlinear beam expanders make use of higher-order multipole magnets and dithering dipoles to expand the beam to a uniform-density, 16-cm wide by 160-cm high rectangular profile on the tritium-production target. The overall optics design will be reviewed, and beam simulations will be presented

  9. A practicable detection system for genetically modified rice by SERS-barcoded nanosensors.

    Science.gov (United States)

    Chen, Kun; Han, Heyou; Luo, Zhihui; Wang, Yanjun; Wang, Xiuping

    2012-04-15

    Since the global cultivation of genetically modified crops constantly expands, it remains a high demand to establish different ways to sort food and feed that consist or contain genetically modified organisms. Surface-enhanced Raman scattering (SERS) spectroscopy is a flexible tool for biological analysis due to its excellent properties for detecting wide varieties of target biomolecules including nucleic acids. In the present study, a SERS-barcoded nanosensor was developed to detect Bacillus thuringiensis (Bt) gene-transformed rice expressing insecticidal proteins. The barcoded sensor was designed by encapsulation of gold nanoparticles with silica and conjugation of oligonucleotide strands for targeting DNA strands. The transition between the cry1A(b) and cry1A(c) fusion gene sequence was used to construct a specific SERS-based detection method with a detection limit of 0.1 pg/mL. In order to build the determination models to screen transgene, a series mixture of Bt rice and normal rice were prepared for SERS assay, and the limit of detection was 0.1% (w/w) transgenic Bt rice relative to normal rice. The sensitivity and accuracy of the SERS-based assay was comparable with real-time PCR. The SERS-barcoded analytical method would provide precise detection of transgenic rice varieties but also informative supplement to avoid false positive outcomes. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  10. Modified-Collins cryocooler for zero-boiloff storage of cryogenic fuels in space

    Science.gov (United States)

    Hannon, Charles L.; Krass, Brady; Hogan, Jake; Brisson, John

    2012-06-01

    Future lunar and planetary explorations will require the storage of cryogenic propellants, particularly liquid oxygen (LOX) and liquid hydrogen (LH2), in low earth orbit (LEO) for periods of time ranging from days to months, and possibly longer. Without careful thermal management, significant quantities of stored liquid cryogens can be lost due to boil-off. Boil-off can be minimized by a variety of passive means including insulation, sun shades and passive radiational cooling. However, it has been shown that active cooling using space cryocoolers has the potential to result in Zero Boil-Off (ZBO) and the launch-mass savings using active cooling exceeds that of passive cooling of LOX for mission durations in LEO of less than 1 week, and for LH2 after about 2 months in LEO. Large-scale DC-flow cryogenic refrigeration systems operate at a fraction of the specific power levels required by small-scale AC-flow cryocoolers. The efficiency advantage of DC-flow cryogenic cycles motivates the current development of a cryocooler based on a modification of the Collins Cycle. The modified Collins cycle design employs piston type expanders that support high operating pressure ratios, electromagnetic valves that enable "floating pistons", and recuperative heat transfer. This paper will describe the design of a prototype Modified-Collins cryocooler for ZBO storage of cryogenic fuels in space.

  11. Impaired heat shock response in cells expressing full-length polyglutamine-expanded huntingtin.

    Directory of Open Access Journals (Sweden)

    Sidhartha M Chafekar

    Full Text Available The molecular mechanisms by which polyglutamine (polyQ-expanded huntingtin (Htt causes neurodegeneration in Huntington's disease (HD remain unclear. The malfunction of cellular proteostasis has been suggested as central in HD pathogenesis and also as a target of therapeutic interventions for the treatment of HD. We present results that offer a previously unexplored perspective regarding impaired proteostasis in HD. We find that, under non-stress conditions, the proteostatic capacity of cells expressing full length polyQ-expanded Htt is adequate. Yet, under stress conditions, the presence of polyQ-expanded Htt impairs the heat shock response, a key component of cellular proteostasis. This impaired heat shock response results in a reduced capacity to withstand the damage caused by cellular stress. We demonstrate that in cells expressing polyQ-expanded Htt the levels of heat shock transcription factor 1 (HSF1 are reduced, and, as a consequence, these cells have an impaired a heat shock response. Also, we found reduced HSF1 and HSP70 levels in the striata of HD knock-in mice when compared to wild-type mice. Our results suggests that full length, non-aggregated polyQ-expanded Htt blocks the effective induction of the heat shock response under stress conditions and may thus trigger the accumulation of cellular damage during the course of HD pathogenesis.

  12. Expanding policy options for educating teenagers.

    Science.gov (United States)

    Stern, David

    2009-01-01

    David Stern argues that some basic features of the American high school must be modified if it is to serve all students successfully. He notes, for example, that only three-quarters of U.S. high school students graduate four years after beginning ninth grade and that the National Assessment of Educational Progress found no improvement in reading or mathematics for seventeen-year-olds between 1971 and 2004. The nation's system for educating teenagers, says Stern, seems to be stuck, despite the constant efforts of teachers and repeated waves of reform. Citing two widely accepted public purposes of educating teenagers-preparation for civic participation and for economic self-sufficiency-Stern proposes four new strategies to achieve those goals. He draws on empirical evidence suggesting that these are promising directions for research and policy, but acknowledges that existing studies provide only limited guidance. First, he says, schools should continue the current trend toward integrating educational options to provide young people with skills and experiences that pave the way to both college and careers. Second, states and districts should tie education funding not simply to the number of students attending school, but also to what young people learn, whether they graduate, and whether they find jobs or enroll in postsecondary education. Such a move, he argues, would encourage teaching and learning formats that use students' time more effectively. Third, more adults in addition to classroom teachers should be involved in educating teenagers. Other adults acting as academic advisers, learning coaches, student advocates, internship supervisors, mentors, and college counselors could help guide the education of teenagers inside and outside of school and provide some relief for the chronic shortage of teachers. Fourth, schools should expand the options for educating teenagers outside of geographically fixed schools. Combining improved Internet-based curriculum with

  13. Modified graphene/polyimide nanocomposites: reinforcing and tribological effects.

    Science.gov (United States)

    Huang, Ting; Xin, Yuanshi; Li, Tongsheng; Nutt, Steven; Su, Chao; Chen, Haiming; Liu, Pei; Lai, Zuliang

    2013-06-12

    By taking advantage of design and construction of strong graphene-matrix interfaces, we have prepared modified graphene/polyimide (MG/PI) nanocomposites via a two-stage process consisting of (a) surface modification of graphene and (b) in situ polymerization. The 2 wt % MG/PI nanocomposites exhibited a 20-fold increase in wear resistance and a 12% reduction in friction coefficient, constituting a potential breakthrough for future tribological application. Simultaneously, MG also enhanced thermal stability, electrical conductivity, and mechanical properties, including tensile strength, Young's modulus, storage modulus, and microhardness. Excellent thermal stability and compatibility of interface, strong covalent adhesion interaction and mechanical interlocking at the interface, as well as homogeneous and oriented dispersion of MG were achieved here, contributing to the enhanced properties observed here. The superior wear resistance is ascribed to (a) tribological effect of MG, including suppression effect of MG in the generation of wear debris and protective effect of MG against the friction force, and (b) the increase in mechanical properties. In light of the relatively low cost and the unique properties of graphene, the results of this study highlight a pathway to expand the engineering applications of graphene and solve wear-related mechanical failures of polymer parts.

  14. Non-activated high surface area expanded graphite oxide for supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Vermisoglou, E.C.; Giannakopoulou, T.; Romanos, G.E.; Boukos, N.; Giannouri, M. [Institute of Nanoscience and Nanotechnology “Demokritos”, 153 43 Ag. Paraskevi, Attikis (Greece); Lei, C.; Lekakou, C. [Division of Mechanical, Medical, and Aerospace Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 7XH (United Kingdom); Trapalis, C., E-mail: c.trapalis@inn.demokritos.gr [Institute of Nanoscience and Nanotechnology “Demokritos”, 153 43 Ag. Paraskevi, Attikis (Greece)

    2015-12-15

    Graphical abstract: - Highlights: • One-step exfoliation and reduction of graphite oxide via microwave irradiation. • Effect of pristine graphite (type, flake size) on the microwave expanded material. • Effect of pretreatment and oxidation cycles on the produced expanded material. • Expanded graphene materials with high BET surface areas (940 m{sup 2}/g–2490 m{sup 2}/g). • Non-activated graphene based materials suitable for supercapacitors. - Abstract: Microwave irradiation of graphite oxide constitutes a facile route toward production of reduced graphene oxide, since during this treatment both exfoliation and reduction of graphite oxide occurs. In this work, the effect of pristine graphite (type, size of flakes), pretreatment and oxidation cycles on the finally produced expanded material was examined. All the types of graphite that were tested afforded materials with high BET surface areas ranging from 940 m{sup 2}/g to 2490 m{sup 2}/g, without intervening an activation stage at elevated temperature. SEM and TEM images displayed exfoliated structures, where the flakes were significantly detached and curved. The quality of the reduced graphene oxide sheets was evidenced both by X-ray photoelectron spectroscopy and Raman spectroscopy. The electrode material capacitance was determined via electrochemical impedance spectroscopy and cyclic voltammetry. The materials with PEDOT binder had better performance (∼97 F/g) at low operation rates while those with PVDF binder performed better (∼20 F/g) at higher rates, opening up perspectives for their application in supercapacitors.

  15. Response of Balloon-Expandable Endoprosthetic Metallic Stents Subjected to Over-Expansion In Vitro

    International Nuclear Information System (INIS)

    Montague, B. J.; Kakimoto, W. M.; Arepally, A.; Razavi, M.; Dake, M. D.; Hofmann, L. V.

    2004-01-01

    We attempted to evaluate the in vitro behavior and performance of balloon-expandable endoprosthetic metallic stents subjected to over-expansion (OE). Seventy-two balloon-expandable endoprosthetic stents, representing 22 models from six manufacturers, were over- expanded in vitro. Stents were initially expanded to their maximum manufacturer- recommended diameter and then over-expanded incrementally to their endpoints. Endpoints for OE were either stent disarticulation or an inability to undergo further expansion despite balloon insufflation to maximum burst pressure. Measurements of stent dimensions were recorded at each overexpanded diameter and comparisons were made to manufacturer's specifications. A total of 288 balloon-driven expansions were performed on 72 stents. Sixteen stents were expanded to large diameters (≥ 16 mm), 20 stents underwent OE of 50% or greater. One model tended to disarticulate after OE greater than 50%. There were five models that had a tendency to disarticulate after minimal OE. Five models were resistant to OE (25% or less OE) but did not disarticulate. Nearly all stents showed some degree of foreshortening with OE, while 36 stents underwent foreshortening of 30% or more. Models that are not recommended for OE include Intrastent, Intrastent DoubleStrut, NIR Royale and Omniflex. Good candidates for OE include Intrastent DoubleStrut LD, Palmaz large, Medtronic Extra Support Biliary Plus and Medtronic Flexible Biliary. Palmaz XL remains the only model available for expansion from 20 to 28 mm in diameter. For the remaining stents, OE is possible, however, caution should be used

  16. Expanding the Audience for the Performing Arts.

    Science.gov (United States)

    Andreasen, Alan R.

    Becoming involved in the arts is a process that involves movement through several stages, from disinterest to active attendance at and enthusiasm for performing arts events. Since target consumers at any time will differ in their placement on this continuum, marketing programs to expand arts audiences must first identify where each target segment…

  17. The option to expand a project: its assessment with the binomial options pricing model

    Directory of Open Access Journals (Sweden)

    Salvador Cruz Rambaud

    Full Text Available Traditional methods of investment appraisal, like the Net Present Value, are not able to include the value of the operational flexibility of the project. In this paper, real options, and more specifically the option to expand, are assumed to be included in the project information in addition to the expected cash flows. Thus, to calculate the total value of the project, we are going to apply the methodology of the Net Present Value to the different scenarios derived from the existence of the real option to expand. Taking into account the analogy between real and financial options, the value of including an option to expand is explored by using the binomial options pricing model. In this way, estimating the value of the option to expand is a tool which facilitates the control of the uncertainty element implicit in the project. Keywords: Real options, Option to expand, Binomial options pricing model, Investment project appraisal

  18. Characterization of modified clinoptilolite

    International Nuclear Information System (INIS)

    Novosad, J.; Jandl, J.; Woollins, J.D.

    1992-01-01

    Samples of clinoptilolite were modified using insoluble hexacyanoferrate from aqueous solution. The modified samples were characterized by elemental analysis, powder X-ray diffraction, solid state NMR and vibrational spectroscopy. The sorption properties of modified clinoptilolite were studied, too. Higher affinity for 137 Cs sorption in comparison with the natural clinoptilolite has been proved. (author) 5 refs.; 3 figs.; 2 tabs

  19. Chinese IP expands with self-reliance.

    Science.gov (United States)

    1999-05-01

    In 1999, program officers from JOICFP visited five of 10 projects where JOICFP has provided direct assistance during 1993-95 to enhance health education in China's integrated family planning, maternal-child health programs. The JOICFP team and three members of the Chinese National Steering Committee of the Integrated Projects visited project areas in remote and mountainous areas that are characterized by underdevelopment, low income rates, low rates of hospital deliveries, and high rates of parasitic infection. The monitoring team found that all project areas continued the projects after completion of the 3-year period and even expanded efforts to cover other areas. By 1998, more than a million people had been served, which is quadruple the initial target number. The team found that the program could benefit from additional assistance in training new staff to interact with the public and to use IEC (information, education, communication) materials appropriately. One project area, Shaowu City, opened a new Family Health Service Center in August 1998 with a grant from the Japanese Grant Assistance for Grassroots Projects and assistance from its provincial and local government. This Center serves women and children and adolescents on a fee-charged basis and hopes to expand its service area.

  20. The expanding EU

    DEFF Research Database (Denmark)

    Zank, Wolfgang

    In this paper I try to explore whether the EU can go on expanding and thereby become culturally ever more diversified, and at the same retain its stability. The answer is, in principle, affirmative. Europe has always been much diversified, and therefore it is not possible to define a European...... identity in terms of particular cultural traditions. However, in spite of their diversity, the EU-member countries are united by their adherence to the principles of democracy, rule by law and human rights. Countries which do not share this basic consensus would not be accepted as members, nor is it likely...... that they would apply for it. An essential part is the willingness of member states to accept a reduction of national sovereignty on some important policy fields. The EU project is basically about lifting the principles of democracy and rule by law on the international level, most and foremost among the member...

  1. Visual Narratives and (AntiExpanded Cinema in Julião Sarmento

    Directory of Open Access Journals (Sweden)

    Miguel Mesquita Duarte

    2015-02-01

    Full Text Available Beyond the difficulties in circumscribing expanded cinema theoretical and epistemological field – due to the plurality and multiple developments that it comprises, - one of the most pressing aspects concerning expanded cinema refers its relation with problems of narrativity. Although less obvious, the mention to Julião Sarmento’s work in this field seems to us particularly useful; to begin with, for the way his work is animated by a counter-narrative compulsion which, building up in the interior of a specific dialectic between cinema and photography, efficiently undermines structural centeredness and the linearity of sequential images. Following a thread encompassing the experimental films from the mid-70s to the installations of 2000s, we seek to argue that the importance of structuralism, as well the genealogical approach to the history and memory of cinema, constitute, within Sarmento’s oeuvre, increasingly important aspects to assess the new forms of perceptive, cognitive and topological arrangements that go along the emergence of the so called expanded cinema. Ultimately, the originality and the critical stance maintained by the artist leads us towards the consideration of an anti-expanded-cinema: more than a thematic traced within the limits of technological development and multi-disciplinary spreading, in Sarmento’s case, the expansion of cinema concerns, mostly, the expansion of the criteria related with the circulation of thought and desire throughout a topology of infra-signification that emerges from the new possibilities of narration, of making and exhibiting cinema. Accordingly, what is at issue is an overall distinct possibility of identify, designate and problematize the category of expanded cinema, beyond its orthodox definition.

  2. Small Engines as Bottoming Cycle Steam Expanders for Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Rohitha Weerasinghe

    2017-01-01

    Full Text Available Heat recovery bottoming cycles for internal combustion engines have opened new avenues for research into small steam expanders (Stobart and Weerasinghe, 2006. Dependable data for small steam expanders will allow us to predict their suitability as bottoming cycle engines and the fuel economy achieved by using them as bottoming cycles. Present paper is based on results of experiments carried out on small scale Wankel and two-stroke reciprocating engines as air expanders and as steam expanders. A test facility developed at Sussex used for measurements is comprised of a torque, power and speed measurements, electronic actuation of valves, synchronized data acquisition of pressure, and temperatures of steam and inside of the engines for steam and internal combustion cycles. Results are presented for four engine modes, namely, reciprocating engine in uniflow steam expansion mode and air expansion mode and rotary Wankel engine in steam expansion mode and air expansion mode. The air tests will provide base data for friction and motoring effects whereas steam tests will tell how effective the engines will be in this mode. Results for power, torque, and p-V diagrams are compared to determine the change in performance from air expansion mode to steam expansion mode.

  3. Exergy analysis of transcritical carbon dioxide refrigeration cycle with an expander

    International Nuclear Information System (INIS)

    Yang Junlan; Ma Yitai; Li Minxia; Guan Haiqing

    2005-01-01

    In this paper, a comparative study is performed for the transcritical carbon dioxide refrigeration cycles with a throttling valve and with an expander, based on the first and second laws of thermodynamics. The effects of evaporating temperature and outlet temperature of gas cooler on the optimal heat rejection pressure, the coefficients of performance (COP), the exergy losses, and the exergy efficiencies are investigated. In order to identify the amounts and locations of irreversibility within the two cycles, exergy analysis is employed to study the thermodynamics process in each component. It is found that in the throttling valve cycle, the largest exergy loss occurs in the throttling valve, about 38% of the total cycle irreversibility. In the expander cycle, the irreversibility mainly comes from the gas cooler and the compressor, approximately 38% and 35%, respectively. The COP and exergy efficiency of the expander cycle are on average 33% and 30% higher than those of the throttling valve cycle, respectively. It is also concluded that an optimal heat rejection pressure can be obtained for all the operating conditions to maximize the COP. The analysis results are of significance to provide theoretical basis for optimization design and operation control of the transcritical carbon dioxide cycle with an expander

  4. Comparison of covered and uncovered self-expandable stents in the treatment of malignant biliary obstruction.

    Science.gov (United States)

    Flores Carmona, Diana Yamel; Alonso Lárraga, Juan Octavio; Hernández Guerrero, Angélica; Ramírez Solís, Mauro Eduardo

    2016-05-01

    Drainage with metallic stents is the treatment of choice in malignant obstructive jaundice. Technical and clinical success with metallic stents is obtained in over 90% and 80% of cases, respectively. There are self-expandable metallic stents designed to increase permeability. The aim of this study was to describe the results obtained with totally covered self-expandable and uncovered self-expandable metallic stents in the palliative treatment of malignant biliary obstruction. Sixty eight patients with malignant obstructive jaundice secondary to pancreatobiliary or metastatic disease not amenable to surgery were retrospectively included. Two groups were created: group A (covered self-expandable metallic stents) (n = 22) and group B (uncovered self-expandable metallic stents) (n = 46). Serum total bilirubin, direct bilirubin, alkaline phosphatase and gamma glutamyl transferase levels decreased in both groups and no statistically significant difference was detected (p = 0.800, p = 0.190, p = 0.743, p = 0.521). Migration was greater with covered stents but it was not statistically significant either (p = 0.101). Obstruction was greater in the group with uncovered stents but it was not statistically significant either (p = 0.476). There are no differences when using covered self-expandable stents or uncovered self-expandable stents in terms of technical and clinical success or complications in the palliative treatment of malignant obstructive jaundice.

  5. Feathermoss and epiphytic Nostoc cooperate differently: expanding the spectrum of plant–cyanobacteria symbiosis

    Energy Technology Data Exchange (ETDEWEB)

    Warshan, Denis; Espinoza, Josh L.; Stuart, Rhona; Richter, Alexander R.; Kim, Sea-Yong; Shapiro, Nicole; Woyke, Tanja; Kyripides, Nikos; Barry, Kerrie W.; Singan, Vasanth; Lindquist, Erika; Ansong, Charles K.; Purvine, Samuel O.; Brewer, Heather M.; Weyman, Philip D.; Dupont, Chris; Rasmussen, Ulla

    2017-12-31

    Dinitrogen (N2)-fixation by cyanobacteria in symbiosis with feather mosses represents the main pathway of biological N input into boreal forests. Despite its significance, little is known about the gene repertoire needed for the establishment and maintenance of the symbiosis. To determine gene acquisitions or regulatory rewiring allowing cyanobacteria to form this symbiosis, we compared closely related Nostoc strains that were either symbiosis-competent or non-competent, using a proteogenomics approach and a unique experimental setup allowing for controlled chemical and physical contact between partners. Thirty-two protein families were only in the genomes of competent strains, including some never before associated with symbiosis. We identified conserved orthologs that were differentially expressed in competent strains, including gene families involved in chemotaxis and motility, NO regulation, sulfate/phosphate transport, sugar metabolism, and glycosyl-modifying and oxidative stress-mediating exoenzymes. In contrast to other cyanobacteria-plant symbioses, the moss-cyanobacteria epiphytic symbiosis is distinct, with the symbiont retaining motility and chemotaxis, and not modulating N-fixation, photosynthesis, GS-GOGAT cycle, and heterocyst formation. Our work expands our knowledge of plant cyanobacterial symbioses, provides an interaction model of this ecologically significant symbiosis, and suggests new currencies, namely nitric oxide and aliphatic sulfonates, may be involved in establishing and maintaining this symbiosis.

  6. Gravitational instantons and separation of an expanding Universe

    International Nuclear Information System (INIS)

    Rubakov, V.A.; Tinyakov, P.G.

    1988-01-01

    Instanton, describing the separation of closed small-size classically inflating Universe from the plane Universe, was found in the model of gravitational field, interacting with matter fields. Existence of such instantons provides the possibility of expanding Universe self-birth

  7. Expanded and combined uncertainty in measurements by GM counters

    International Nuclear Information System (INIS)

    Stankovic, K.; Arandjic, D.; Lazarevic, Dj.; Osmokrovic, P.

    2007-01-01

    This paper deals with possible ways of obtaining expanded and combined uncertainty in measurements for four types of GM counters with a same counter's tube, in cases when the contributors of these uncertainties are cosmic background radiation and induced overvoltage phenomena. Nowadays, as a consequence of electromagnetic radiation, the latter phenomenon is especially marked in urban environments. Based on experimental results obtained, it has been established that the uncertainties of an influenced random variable 'number of pulses from background radiation' and 'number of pulses induced by overvoltage' depend on the technological solution of the counter's reading system and contribute in different ways to the expanded and combined uncertainty in measurements of the applied types of GM counters. (author)

  8. Adipose tissue expandability and the early origins of PCOS.

    Science.gov (United States)

    de Zegher, Francis; Lopez-Bermejo, Abel; Ibáñez, Lourdes

    2009-11-01

    The most prevalent phenotypes of polycystic ovary syndrome (PCOS) are characterized by insulin resistance and androgen excess. The adipose tissue (AT) expandability hypothesis explains the development of insulin resistance in obesity and in cases of AT deficit. In line with this hypothesis, we propose that hyperinsulinemic androgen excess in PCOS is often underpinned by exhaustion of the capacity to expand subcutaneous AT in a metabolically safe way. Such exhaustion might occur when a positive energy imbalance meets a normal fat-storage capacity and/or when a normal energy balance faces a low fat storage capacity. This concept thus explains how PCOS phenotypes might result from obesity, prenatal growth restraint or a genetic lipodystrophy, or, experimentally, from prenatal androgen excess.

  9. The Dichotomous Cosmology with a Static Material World and Expanding Luminous World

    Directory of Open Access Journals (Sweden)

    Heymann Y.

    2014-07-01

    Full Text Available The dichotomous cosmology is an alternative to the expanding Universe theory, and consists of a static matter Universe, where cosmological redshifts are explained by a tired-light model with an expanding luminous world. In this model the Hubble constant is also the photon energy decay rate, and the luminous world i s expanding at a constant rate as in de Sitter cosmology for an empty Universe. The present model explains both the luminosity distance versus redshift relationship of supernovae Ia, and ageing of spectra observed with the stretching of supernovae light curves. Furthermore, it is consistent with a radiation energy density factor (1 + z 4 inferred from the Cosmic Microwave Background Radiation.

  10. Self-Expanding Metal Stenting for Palliation of Patients with Malignant Colonic Obstruction

    DEFF Research Database (Denmark)

    Meisner, Søren; González-Huix, Ferran; Vandervoort, Jo G

    2012-01-01

    Background. Self-expanding metal stents can alleviate malignant colonic obstruction in incurable patients and avoid palliative stoma surgery. Objective. Evaluate stent effectiveness and safety on palliation of patients with malignant colorectal strictures. Design. Two prospective, one Spanish....... Interventions(s). Self-expanding metal stent placement. Main Outcome Measures. Procedural success, clinical success, and safety. Results. Procedural success was 98.4% (251). Clinical success rates were 87.8% at 30 days, 89.7% at 3 months, 92.8% at 6 months, and 96% at 12 months. Overall perforation rate was 5...... for patients with malignant colonic obstruction should be self-expanding metal stent placement due to high rates of technical success and efficacy in symptom palliation and few complications....

  11. Pancreatitis-Associated Splenic Artery Pseudoaneurysm: Endovascular Treatment with Self-Expandable Stent-Grafts

    International Nuclear Information System (INIS)

    Brountzos, Elias N.; Vagenas, Kostantinos; Apostolopoulou, Sotiria C.; Panagiotou, Irene; Lymberopoulou, Dimitra; Kelekis, Dimitrios A.

    2003-01-01

    We present a patient with a splenic arterypseudoaneurysm (SAPA) treated with placement of self-expandable stent-grafts. The procedure was complicated by stent-graft migration,but successful management resulted in lasting exclusion of the SAPA,while the patency of the splenic artery was preserved. This is the first report of self-expandable stent-graft treatment of SAPA

  12. Aflatoxin Toxicity Reduction in Feed by Enhanced Binding to Surface-Modified Clay Additives

    Science.gov (United States)

    Jaynes, William F.; Zartman, Richard E.

    2011-01-01

    Animal feeding studies have demonstrated that clay additives, such as bentonites, can bind aflatoxins in ingested feed and reduce or eliminate the toxicity. Bentonite deposits are found throughout the world and mostly consist of expandable smectite minerals, such as montmorillonite. The surfaces of smectite minerals can be treated with organic compounds to create surface-modified clays that more readily bind some contaminants than the untreated clay. Montmorillonites treated with organic cations, such as hexadecyltrimethylammonium (HDTMA) and phenyltrimethylammonium (PTMA), more effectively remove organic contaminants, such as benzene and toluene, from water than untreated clay. Similarly, montmorillonite treated with PTMA (Kd = 24,100) retained more aflatoxin B1 (AfB1) from aqueous corn flour than untreated montmorillonite (Kd = 944). Feed additives that reduced aflatoxin toxicity in animal feeding studies adsorbed more AfB1 from aqueous corn flour than feed additives that were less effective. The organic cations HDTMA and PTMA are considered toxic and would not be suitable for clay additives used in feed or food, but other non-toxic or nutrient compounds can be used to prepare surface-modified clays. Montmorillonite (SWy) treated with choline (Kd = 13,800) and carnitine (Kd = 3960) adsorbed much more AfB1 from aqueous corn flour than the untreated clay (Kd = 944). A choline-treated clay prepared from a reduced-charge, high-charge montmorillonite (Kd = 20,100) adsorbed more AfB1 than the choline-treated high-charge montmorillonite (Kd = 1340) or the untreated montmorillonite (Kd = 293). Surface-modified clay additives prepared using low-charge smectites and nutrient or non-toxic organic compounds might be used to more effectively bind aflatoxins in contaminated feed or food and prevent toxicity. PMID:22069725

  13. On the elusive crystal structure of expanded austenite

    DEFF Research Database (Denmark)

    Brink, Bastian; Ståhl, Kenny; Christiansen, Thomas Lundin

    2017-01-01

    No consistent structural description exists for expanded austenite that accurately accounts for the hkl-dependent peak shifts and broadening observed in diffraction experiments. The best available description for homogeneous samples is a face-centered cubic lattice with stacking faults. Here Deby...

  14. DEMONSTRATION OF PACKAGING MATERIALS ALTERNATIVES TO EXPANDED POLYSTYRENE

    Science.gov (United States)

    This report represents the second demonstration of cleaner technologies to support the goals of the 33/50 Program under the EPA Cooperative Agreement No. CR-821848. The report presents assessment results of alternative packaging materials which could potentially replace expanded...

  15. Building the Case: Changing Consumer Perceptions of the Value of Expanded Community Pharmacist Services.

    Science.gov (United States)

    Steckowych, Kathryn; Smith, Marie; Spiggle, Susan; Stevens, Andrew; Li, Hao

    2018-01-01

    The role of the community pharmacist has traditionally been a medication dispenser; however, community pharmacists' responsibilities must expand to include more direct patient care services in order to transform primary care practice. Use case-based scenarios to (1) determine factors that contribute to positive and negative consumer perceptions of expanded community pharmacist patient care roles, (2) identify facilitators and barriers that contribute to consumer perceptions of the value of expanded community pharmacist patient care services, and (3) develop a successful approach and strategies for increasing consumer advocacy for the value of expanded community pharmacist patient care services. Two consumer focus groups used scenario-based guided discussions and Likert scale questionnaires to elicit consumer reactions, facilitators, and barriers to expanded community pharmacist services. Convenience, timeliness, and accessibility were common positive reactions across all 3 scenarios. Team approach to care and trust were viewed as major facilitators. Participant concerns included uncertainty about pharmacist training and qualifications, privacy, pharmacists' limited bandwidth to accept new tasks, and potential increased patient costs. Common barriers to service uptake included a lack of insurance payment and physician preference to provide the services. Consumer unfamiliarity with non-traditional community pharmacist services is likely an influencer of consumers' hesitancy to utilize such services; therefore, an opportunity exists to engage consumers and advocacy organizations in supporting expanded community pharmacist roles. This study can inform consumers, advocates, community pharmacists, primary care providers, and community-based organizations on methods to shape consumer perceptions on the value of community pharmacist expanded services.

  16. Treatment of Benign Tracheal Stenosis Utilizing Self-Expanding Nitinol Stents

    International Nuclear Information System (INIS)

    Sesterhenn, Andreas M.; Wagner, Hans-Joachim; Alfke, Heiko; Werner, Jochen A.; Lippert, Burkard M.

    2004-01-01

    We assessed the results of self-expanding metallic stent insertion into benign proximal tracheal stenosis in patients not appropriate or unfit for surgical repair. Proximal benign tracheal stenoses had occurred in 11 patients (7 men, 4 women, mean age 68.8 years) after long-time intubation (n = 6), tracheostomy (n = 4), or chondropathia (n = 1). Fourteen self-expanding nitinol stents were placed in the patients under general anesthesia with endoscopical and fluoroscopical guidance. Stent insertion was successful in all cases and led to immediate relief of the morphological and functional airway obstruction. No immediate complications were noted. During the mean follow-up period of 67.5 weeks we observed one recurrent dyspnea 3 months after implantation and granuloma formation at the stent insertion site in another patient. Both complications were successfully treated with additional stent insertion in one case and laser resection of granulomas in the other. Self-expanding nitinol stents should be considered for the treatment of benign proximal tracheal obstruction in selected patients for whom surgical repair is contraindicated

  17. Robust size illusion produced by expanding and contracting flow fields.

    Science.gov (United States)

    Dong, Xue; Bai, Jianying; Bao, Min

    2017-04-01

    A new illusion is described. Randomly positioned dots moved radially within an imaginary annular window. The dots' motion periodically changed the direction, leading to an alternating percept of expanding and contracting motion. Strikingly, the apparent size of the enclosed circular region shrank during the dots' expanding phases and dilated during the contracting phases. We quantitatively measured the illusion, and found that the presence of energy at the local kinetic edge could not account for the illusion. Besides, we reproduced the illusion on a natural scene background seen from a first-person point of view that moved forward and backward periodically. Blurring the boundaries of motion areas could not reverse the illusion in all subjects. Taken together, our observed illusion is likely induced by optic flow processing with some components of motion contrast. Expanding or contracting dots may induce the self-motion perception of either approaching or leaving way from the circle. These will make the circle appear smaller or larger since its retinal size remains constant. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Combined expander-compressor for carbon dioxide in free piston design; Kombinierte Expansions-Kompressions-Maschine fuer Kohlendioxid in Freikolbenbauweise

    Energy Technology Data Exchange (ETDEWEB)

    Heyl, P.; Quack, H. [TU, Dresden (Germany). Lehrstuhl fuer Kaelte- und Kryotechnik; Kuehne, M. [TU, Dresden (Germany). Lehrstuhl fuer Pumpen, Verdichter und Apparate

    2000-03-01

    The renaissance of carbon dioxide in refrigeration engineering is impressive. The contribution shows that the disadvantages of this refrigerating fluid can be compensated by modifying the refrigeration circuit. A combined expander-compressor working by the free piston principle and developed at Dresden Technical University is described. [German] Kohlendioxid erlebt im Bereich der Kaeltetechnik infolge der schwierigen Suche nach umweltvertraeglichen Ersatzkaeltemitteln fuer die Fluorchlorkohlenwasserstoffe eine beeindruckende Renaissance. Es soll anhand thermodynamischer Prozessberechnungen gezeigt werden, dass durch die Modifikation des Kreisprozesses unter Beachtung der besonderen thermodynamischen Eigenschaften des Kohlendioxids diese Nachteile bereits bei der theoretischen Leistungszahl ausgeglichen werden koennen. Dafuer wird das Kohlendioxid in einem Prozess mit zweistufiger Verdichtung arbeitsleistend entspannt. Die Besonderheit dieses Prozesses ist die Verwendung einer speziell fuer diesen Anwendungsfall entwickelten Maschine, die die gewonnene Expansionsarbeit direkt fuer die Verdichtung des Kohlendioxids in der zweiten Verdichtungsstufe nutzt. Es handelt sich dabei um eine nach dem Freikolbenprinzip arbeitende Expansions-Kompressions-Maschine, die an der TU Dresden entwickelt und gegenwaertig getestet wird. (orig.)

  19. Expanding the Bethe/Gauge dictionary

    Science.gov (United States)

    Bullimore, Mathew; Kim, Hee-Cheol; Lukowski, Tomasz

    2017-11-01

    We expand the Bethe/Gauge dictionary between the XXX Heisenberg spin chain and 2d N = (2, 2) supersymmetric gauge theories to include aspects of the algebraic Bethe ansatz. We construct the wave functions of off-shell Bethe states as orbifold defects in the A-twisted supersymmetric gauge theory and study their correlation functions. We also present an alternative description of off-shell Bethe states as boundary conditions in an effective N = 4 supersymmetric quantum mechanics. Finally, we interpret spin chain R-matrices as correlation functions of Janus interfaces for mass parameters in the supersymmetric quantum mechanics.

  20. Expanding the taxonomy of the diagnostic criteria for temporomandibular disorders.

    Science.gov (United States)

    Peck, C C; Goulet, J-P; Lobbezoo, F; Schiffman, E L; Alstergren, P; Anderson, G C; de Leeuw, R; Jensen, R; Michelotti, A; Ohrbach, R; Petersson, A; List, T

    2014-01-01

    There is a need to expand the current temporomandibular disorders' (TMDs) classification to include less common but clinically important disorders. The immediate aim was to develop a consensus-based classification system and associated diagnostic criteria that have clinical and research utility for less common TMDs. The long-term aim was to establish a foundation, vis-à-vis this classification system, that will stimulate data collection, validity testing and further criteria refinement. A working group [members of the International RDC/TMD Consortium Network of the International Association for Dental Research (IADR), members of the Orofacial Pain Special Interest Group (SIG) of the International Association for the Study of Pain (IASP), and members from other professional societies] reviewed disorders for inclusion based on clinical significance, the availability of plausible diagnostic criteria and the ability to operationalise and study the criteria. The disorders were derived from the literature when possible and based on expert opinion as necessary. The expanded TMDs taxonomy was presented for feedback at international meetings. Of 56 disorders considered, 37 were included in the expanded taxonomy and were placed into the following four categories: temporomandibular joint disorders, masticatory muscle disorders, headache disorders and disorders affecting associated structures. Those excluded were extremely uncommon, lacking operationalised diagnostic criteria, not clearly related to TMDs, or not sufficiently distinct from disorders already included within the taxonomy. The expanded TMDs taxonomy offers an integrated approach to clinical diagnosis and provides a framework for further research to operationalise and test the proposed taxonomy and diagnostic criteria. © 2014 John Wiley & Sons Ltd.

  1. The Expanding Marketplace for Applied Geophysics

    Science.gov (United States)

    Carlson, N.; Sirles, P.

    2012-12-01

    While the image of geophysics for the proverbial "layman" often seems limited to volcanoes and earthquakes, and to the geoscientist this image enlarges to include oil or minerals exploration and whole earth studies, there has been a steady increase in the application of geophysics into the realm of "daily life", such as real estate deals, highway infrastructure, and flood protection. This expansion of applications can be attributed to the improved economics from advances in equipment and interpretation. Traditional geophysical methods that at one time often only fit within the budgets of oil, gas, and minerals exploration programs can now be economically applied to much smaller scale needs like contaminant mapping, landfill delineation, and levee investigations. A real-world, economic example of this expanding marketplace is our company, which began very small and was aimed almost exclusively at the minerals exploration market. Most of our growth has been in the last 10 years, when we have expanded to five offices and a staff with almost 40 geoscientist degrees (21 in geophysics); much of this growth has been in the non-oil, non-minerals arenas. While much of our work still includes minerals exploration, other projects this year include wind-farm foundation studies, cavity detection above underground nuclear tests, landfill studies, acid mine drainage problems, and leaks in evaporation ponds. A methodology example of this expanding market is the induced polarization (IP) survey, once primarily used for minerals exploration, particularly large porphyry copper deposits, but now efficient enough to also use in environmental studies. The IP method has been particularly useful in delineating and characterizing old, poorly documented landfills, and recent research suggests it may also be useful in monitoring the accelerated biodegradation processes used in some cases to rehabilitate the sites. Compared to temperature monitoring systems, IP may be more useful in providing

  2. Uranium requirements for advanced fuel cycles in expanding nuclear power systems

    International Nuclear Information System (INIS)

    Banerjee, S.; Tamm, H.

    1978-01-01

    When considering advanced fuel cycle strategies in rapidly expanding nuclear power systems, equilibrium analyses do not apply. A computer simulation that accounts for system delay times and fissile inventories has been used to study the effects of different fuel cycles and different power growth rates on uranium consumption. The results show that for a given expansion rate of installed capacity, the main factors that affect resource requirements are the fissile inventory needed to introduce the advanced fuel cycle and the conversion (or breeding) ratio. In rapidly expanding systems, the effect of fissile inventory dominates, whereas in slowly expanding systems, conversion or breeding ratio dominates. Heavy-water-moderated and -cooled reactors, with their high conversion ratios, appear to be adaptable vehicles for accommodating fuel cycles covering a wide range of initial fissile inventories. They are therefore particularly suitable for conserving uranium over a wide range of nuclear power system expansion rates

  3. Renal Transplant Ureteral Stenosis: Treatment by Self-Expanding Metallic Stent

    International Nuclear Information System (INIS)

    Cantasdemir, Murat; Kantarci, Fatih; Numan, Furuzan; Mihmanli, Ismail; Kalender, Betul

    2003-01-01

    We report the use of a metallic stent in a transplant ureteral stenosis. A 28-year-old man with chronic renal failure due to chronic pyelonephritis, who received a living-donor renal transplant, presented with transplant ureteral stenosis. The stenosis was unresponsive to balloon dilation and was treated by antegrade placement of a self-expanding Memotherm stent. The stentedureter stayed patent for 3 years. It may be reasonable to treat post-transplant ureteral stenosis resistant to balloon dilation with self-expanding metallic stents. However, long-term follow-up is required to evaluate the efficacy of this treatment

  4. Expanded Mixed Multiscale Finite Element Methods and Their Applications for Flows in Porous Media

    KAUST Repository

    Jiang, L.

    2012-01-01

    We develop a family of expanded mixed multiscale finite element methods (MsFEMs) and their hybridizations for second-order elliptic equations. This formulation expands the standard mixed multiscale finite element formulation in the sense that four unknowns (hybrid formulation) are solved simultaneously: pressure, gradient of pressure, velocity, and Lagrange multipliers. We use multiscale basis functions for both the velocity and the gradient of pressure. In the expanded mixed MsFEM framework, we consider both separable and nonseparable spatial scales. Specifically, we analyze the methods in three categories: periodic separable scales, G-convergent separable scales, and a continuum of scales. When there is no scale separation, using some global information can significantly improve the accuracy of the expanded mixed MsFEMs. We present a rigorous convergence analysis of these methods that includes both conforming and nonconforming formulations. Numerical results are presented for various multiscale models of flow in porous media with shale barriers that illustrate the efficacy of the proposed family of expanded mixed MsFEMs. © 2012 Society for Industrial and Applied Mathematics.

  5. The Artful Universe Expanded

    International Nuclear Information System (INIS)

    Bassett, B A

    2005-01-01

    The cosmos is an awfully big place and there is no better guide to its vast expanse and fascinating nooks and crannies than John Barrow. A professor of mathematical sciences at Cambridge University, Barrow embodies that rare combination of highly polished writer and expert scientist. His deft touch brings together the disparate threads of human knowledge and weaves them into a tapestry as rich and interesting for the expert as it is for the layperson. The Artful Universe Expanded is an updated edition of this popular book first published in 1995. It explores the deeply profound manner in which natural law and the nature of the cosmos have moulded and shaped us, our cultures and the very form of our arts and music-a new type of 'cosmic' anthropology. The main themes Barrow chooses for revealing this new anthropology are the subjects of evolution, the size of things, the heavens and the nature of music. The book is a large, eclectic repository of knowledge often unavailable to the layperson, hidden in esoteric libraries around the world. It rivals The Da Vinci Code for entertainment value and insights, but this time it is Nature's code that is revealed. It is rare indeed to find common threads drawn through topics as diverse as The Beetles, Bach and Beethoven or between Jackson Pollock, the Aztecs, Kant, Picasso, Byzantine mosaics, uranium-235 and the helix nebula. Barrow unerringly binds them together, presenting them in a stimulating, conversational style that belies the amount of time that must have gone into researching this book. Dip into it at random, or read it from cover to cover, but do read it. The Artful Universe Expanded is an entertaining antidote to the oft-lamented pressures to know more and more about less and less and the apparently inexorable march of specialization. On reading this book one can, for a short time at least, hold in one's mind a vision that unifies science, art and culture and glimpse a universal tapestry of great beauty. (book review)

  6. The Artful Universe Expanded

    Energy Technology Data Exchange (ETDEWEB)

    Bassett, B A [Institute of Cosmology and Gravitation, University of Portsmouth (United Kingdom)

    2005-07-29

    The cosmos is an awfully big place and there is no better guide to its vast expanse and fascinating nooks and crannies than John Barrow. A professor of mathematical sciences at Cambridge University, Barrow embodies that rare combination of highly polished writer and expert scientist. His deft touch brings together the disparate threads of human knowledge and weaves them into a tapestry as rich and interesting for the expert as it is for the layperson. The Artful Universe Expanded is an updated edition of this popular book first published in 1995. It explores the deeply profound manner in which natural law and the nature of the cosmos have moulded and shaped us, our cultures and the very form of our arts and music-a new type of 'cosmic' anthropology. The main themes Barrow chooses for revealing this new anthropology are the subjects of evolution, the size of things, the heavens and the nature of music. The book is a large, eclectic repository of knowledge often unavailable to the layperson, hidden in esoteric libraries around the world. It rivals The Da Vinci Code for entertainment value and insights, but this time it is Nature's code that is revealed. It is rare indeed to find common threads drawn through topics as diverse as The Beetles, Bach and Beethoven or between Jackson Pollock, the Aztecs, Kant, Picasso, Byzantine mosaics, uranium-235 and the helix nebula. Barrow unerringly binds them together, presenting them in a stimulating, conversational style that belies the amount of time that must have gone into researching this book. Dip into it at random, or read it from cover to cover, but do read it. The Artful Universe Expanded is an entertaining antidote to the oft-lamented pressures to know more and more about less and less and the apparently inexorable march of specialization. On reading this book one can, for a short time at least, hold in one's mind a vision that unifies science, art and culture and glimpse a universal tapestry of great

  7. Shifted-modified Chebyshev filters

    OpenAIRE

    ŞENGÜL, Metin

    2013-01-01

    This paper introduces a new type of filter approximation method that utilizes shifted-modified Chebyshev filters. Construction of the new filters involves the use of shifted-modified Chebyshev polynomials that are formed using the roots of conventional Chebyshev polynomials. The study also includes 2 tables containing the shifted-modified Chebyshev polynomials and the normalized element values for the low-pass prototype filters up to degree 6. The transducer power gain, group dela...

  8. Early recurrence of obstructive jaundice after placement of a self-expanding metal endoprosthesis

    NARCIS (Netherlands)

    Fockens, P.; Waxman, I.; Davids, P. H.; Huibregtse, K.; Tytgat, G. N.

    1992-01-01

    Self-expanding metal endoprostheses have ben used in the treatment of malignant obstructive jaundice for a few years. We report on a patient with obstructive jaundice due to a metastasis of a squamous cell lung cancer into the pancreatic head who received an expandable metal endoprosthesis and

  9. Einstein's conversion from his static to an expanding universe

    Science.gov (United States)

    Nussbaumer, Harry

    2014-02-01

    In 1917 Einstein initiated modern cosmology by postulating, based on general relativity, a homogenous, static, spatially curved universe. To counteract gravitational contraction he introduced the cosmological constant. In 1922 Alexander Friedman showed that Albert Einstein's fundamental equations also allow dynamical worlds, and in 1927 Georges Lemaître, backed by observational evidence, concluded that our universe was expanding. Einstein impetuously rejected Friedman's as well as Lemaître's findings. However, in 1931 he retracted his former static model in favour of a dynamic solution. This investigation follows Einstein on his hesitating path from a static to the expanding universe. Contrary to an often advocated belief the primary motive for his switch was not observational evidence, but the realisation that his static model was unstable.

  10. Agricultural residues and expanded clay in Oncidium baueri Lindl. orchid cultivation

    Directory of Open Access Journals (Sweden)

    Matheus Marchezi Mora

    2015-02-01

    Full Text Available For orchid cultivation in containers is essential to select the right substrate, since this will influence the quality of the final product, it serve as a support for the root system of the plants. This study aimed to evaluate different agricultural residues and expanded clay in Oncidium baueri Lindl. orchid cultivation. The plants were subjected to treatments: pinus husk + carbonized rice husk, pinus husk + coffee husk, pinus husk + fibered coconut, pecan nut husk, expanded clay, fibered coconut, coffee husk, carbonized rice husk, pinus husk. After eleven months of the experiment, the following variables were evaluated: plant height; largest pseudo-bulb diameter; number of buds; shoot fresh dry matter; the longest root length; number of roots; root fresh matter; root dry matter; and electric conductivity; pH and water retention capacity of the substrates. Except the expanded clay, the other substrates showed satisfactory results in one or more traits. Standing out among these substrates pinus husk + coffee husk and pine bark + fibered coconut, which favored the most vegetative and root characteristic of the orchid. The mixture of pinus husk + coffee husk and pinus husk + fibered coconut, provided the best results in vegetative and root growth of the orchid Oncidium baueri and the expanded clay did not show favorable results in the cultivation of this species.

  11. Comparison of Expandable and Fixed Interbody Cages in a Human Cadaver Corpectomy Model: Fatigue Characteristics.

    Science.gov (United States)

    Pekmezci, Murat; Tang, Jessica A; Cheng, Liu; Modak, Ashin; McClellan, Robert T; Buckley, Jenni M; Ames, Christopher P

    2016-11-01

    In vitro cadaver biomechanics study. The goal of this study is to compare the in situ fatigue life of expandable versus fixed interbody cage designs. Expandable cages are becoming more popular, in large part, due to their versatility; however, subsidence and catastrophic failure remain a concern. This in vitro analysis investigates the fatigue life of expandable and fixed interbody cages in a single level human cadaver corpectomy model by evaluating modes of subsidence of expandable and fixed cages as well as change in stiffness of the constructs with cyclic loading. Nineteen specimens from 10 human thoracolumbar spines (T10-L2, L3-L5) were biomechanically evaluated after a single level corpectomy that was reconstructed with an expandable or fixed cage and anterior dual rod instrumentation. All specimens underwent 98 K cycles to simulate 3 months of postoperative weight bearing. In addition, a third group with hyperlordotic cages was used to simulate catastrophic failure that is observed in clinical practice. Three fixed and 2 expandable cages withstood the cyclic loading despite perfect sagittal and coronal plane fitting of the endcaps. The majority of the constructs settled in after initial subsidence. The catastrophic failures that were observed in clinical practice could not be reproduced with hyperlordotic cages. However, all cages in this group subsided, and 60% resulted in endplate fractures during deployment of the cage. Despite greater surface contact area, expandable cages have a trend for higher subsidence rates when compared with fixed cages. When there is edge loading as in the hyperlordotic cage scenario, there is a higher risk of subsidence and intraoperative fracture during deployment of expandable cages.

  12. Modified SEAGULL

    Science.gov (United States)

    Salas, M. D.; Kuehn, M. S.

    1994-01-01

    Original version of program incorporated into program SRGULL (LEW-15093) for use on National Aero-Space Plane project, its duty being to model forebody, inlet, and nozzle portions of vehicle. However, real-gas chemistry effects in hypersonic flow fields limited accuracy of that version, because it assumed perfect-gas properties. As a result, SEAGULL modified according to real-gas equilibrium-chemistry methodology. This program analyzes two-dimensional, hypersonic flows of real gases. Modified version of SEAGULL maintains as much of original program as possible, and retains ability to execute original perfect-gas version.

  13. Electromagnetic fields in an expanding universe

    International Nuclear Information System (INIS)

    Hogan, P.A.; Ellis, G.F.R.

    1989-01-01

    The asymptotic form of the electromagnetic field due to a bounded distribution of charge current in an open, expanding Friedmann--Lemaitre--Robertson--Walker universe is studied. The technique used is to first describe a mechanism for passing from a solution of Maxwell's vacuum field equations on Minkowskian space-time to a solution of Maxwell's field equations in a region free of charge current on the cosmological background. This is tested on the field of an accelerating point charge and then applied to the rigorous treatment of the asymptotic electromagnetic field of a bounded charge-current distribution in Minkowskian space-time given by Goldberg and Kerr [J. Math. Phys. 5, 172 (1964)]. A ''peeling expansion'' of the electromagnetic field in the expanding universe is obtained in inverse powers of a parameter that is proportional to the area distance along the generators of future null cones with vertices on the world line of a fundamental observer. The algebraic character of the two leading coefficients in the expansion is the same as that of the two leading coefficients in the Goldberg--Kerr expansion in Minkowskian space-time. In addition, bounds can be calculated, at any instant in the history of a fundamental observer, on all the coefficients in the peeling expansion, as a consequence of the evaluation of such bounds by Goldberg and Kerr in the case treated by them

  14. Hubble, Hubble's Law and the Expanding Universe

    Indian Academy of Sciences (India)

    Srimath

    H ubble's nam e is associated closely w ith the idea of an expanding universe as he discovered the relation between the recession velocity and the distances of galaxies. H ubble also did a lot of pioneering w ork on the distribution of galaxies in the universe. In this article we take a look at H ubble's law and discuss how it ...

  15. Validity of using modified capillary column with larger diameter to study the Cs diffusion in local Taiwan laterite

    International Nuclear Information System (INIS)

    Tsing-Hai Wang; National Tsing Hua University, Hsinchu, Taiwan; Wen-Chun Yeh; Shih-Chin Tsai; Yi-Lin Jan; Shi-Ping Teng

    2008-01-01

    We have examined the working diameter of capillary columns with diameter of 5, 7, 10 and 20 mm. These modified capillary columns were carefully filled with local Taiwan laterite (LTL). The porosity and density of these packed columns was 0.51±0.02 g/g and 1.27±0.05 g/cm 3 , respectively. The diffusion experiments were then carried out in synthetic groundwater with Cs loading of 0.1mM at room temperature. Experimental results have shown that the diffusion profiles of modified capillary columns fit Fick's second law very well. This result revealed that the working diameter of a capillary column can be expanded to at least to 20 mm without affecting the validity of the derived diffusion coefficients. Among these columns, the ones with 5 mm diameter show the most consistent results of the derived K d , apparent and effective diffusion coefficients. Although the derived distribution and effective diffusion coefficients slightly decrease as the diameter of these columns increases due to the increase of the solid/liquid ratio. These values are still informative of the Cs diffusion in local Taiwan laterite. Moreover, our results clearly demonstrate the potential of using 'modified capillary method' to study the diffusion behaviors of concerned radionuclide because columns with large diameter enable the filling with more versatile geological substances. (author)

  16. Remedial Action Plan for Expanded Bioventing System Facility 6454

    National Research Council Canada - National Science Library

    1996-01-01

    This draft remedial action plan (RAP) presents the scope for an expanded bioventing system for in situ treatment of fuel-contaminated soils at Site 6454 at Vandenberg Air Force Base (AFB), California...

  17. Genetically modified foods and allergy.

    Science.gov (United States)

    Lee, T H; Ho, H K; Leung, T F

    2017-06-01

    2015 marked the 25th anniversary of the commercial use and availability of genetically modified crops. The area of planted biotech crops cultivated globally occupies a cumulative two billion hectares, equivalent to twice the land size of China or the United States. Foods derived from genetically modified plants are widely consumed in many countries and genetically modified soybean protein is extensively used in processed foods throughout the industrialised countries. Genetically modified food technology offers a possible solution to meet current and future challenges in food and medicine. Yet there is a strong undercurrent of anxiety that genetically modified foods are unsafe for human consumption, sometimes fuelled by criticisms based on little or no firm evidence. This has resulted in some countries turning away food destined for famine relief because of the perceived health risks of genetically modified foods. The major concerns include their possible allergenicity and toxicity despite the vigorous testing of genetically modified foods prior to marketing approval. It is imperative that scientists engage the public in a constructive evidence-based dialogue to address these concerns. At the same time, improved validated ways to test the safety of new foods should be developed. A post-launch strategy should be established routinely to allay concerns. Mandatory labelling of genetically modified ingredients should be adopted for the sake of transparency. Such ingredient listing and information facilitate tracing and recall if required.

  18. Expanded Mixed Multiscale Finite Element Methods and Their Applications for Flows in Porous Media

    KAUST Repository

    Jiang, L.; Copeland, D.; Moulton, J. D.

    2012-01-01

    We develop a family of expanded mixed multiscale finite element methods (MsFEMs) and their hybridizations for second-order elliptic equations. This formulation expands the standard mixed multiscale finite element formulation in the sense that four

  19. On Dark Energy and Matter of the Expanding Universe

    Directory of Open Access Journals (Sweden)

    Lehnert B.

    2009-04-01

    Full Text Available At present the expanding universe is observed to be dominated by the not fully under- stood concepts of dark energy and matter, in a conceived almost flat Euclidian geometry. As one of the possible efforts to understand the global behaviour of the expanding uni- verse, the present paper attempts to explain these concepts in terms of the pressure force and gravity of a spherical photon gas cloud of zero point energy, in a flat geometry. A difficult point of the conventional theory concerns the frequency distribution of the zero point energy oscillations which leads to the unacceptable result of an infinite total en- ergy per unit volume. A modification of this distribution is therefore proposed which results in finite energy density. A corresponding equilibrium state is investigated, as well as small dynamic deviations from it, to form a basis for a model of the expanding universe. Provided that the crucial points of the present approach hold true, the model satisfies the requirements of cosmic linear dimensions, results in an estimated accelera- tion of the expansion being of the order of the observed one, presents a possible solution of the coincidence problem of dark energy and matter, and provides one of the possible explanations of the observed excess of high-energy electrons and positrons in recent balloon and satellite experiments.

  20. Stability of stagnation via an expanding accretion shock wave

    International Nuclear Information System (INIS)

    Velikovich, A. L.; Giuliani, J. L.; Murakami, M.; Taylor, B. D.; Zalesak, S. T.; Iwamoto, Y.

    2016-01-01

    Stagnation of a cold plasma streaming to the center or axis of symmetry via an expanding accretion shock wave is ubiquitous in inertial confinement fusion (ICF) and high-energy-density plasma physics, the examples ranging from plasma flows in x-ray-generating Z pinches [Maron et al., Phys. Rev. Lett. 111, 035001 (2013)] to the experiments in support of the recently suggested concept of impact ignition in ICF [Azechi et al., Phys. Rev. Lett. 102, 235002 (2009); Murakami et al., Nucl. Fusion 54, 054007 (2014)]. Some experimental evidence indicates that stagnation via an expanding shock wave is stable, but its stability has never been studied theoretically. We present such analysis for the stagnation that does not involve a rarefaction wave behind the expanding shock front and is described by the classic ideal-gas Noh solution in spherical and cylindrical geometry. In either case, the stagnated flow has been demonstrated to be stable, initial perturbations exhibiting a power-law, oscillatory or monotonic, decay with time for all the eigenmodes. This conclusion has been supported by our simulations done both on a Cartesian grid and on a curvilinear grid in spherical coordinates. Dispersion equation determining the eigenvalues of the problem and explicit formulas for the eigenfunction profiles corresponding to these eigenvalues are presented, making it possible to use the theory for hydrocode verification in two and three dimensions.

  1. Stability of stagnation via an expanding accretion shock wave

    Energy Technology Data Exchange (ETDEWEB)

    Velikovich, A. L.; Giuliani, J. L. [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Murakami, M. [Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan); Taylor, B. D. [Laboratory for Computational Physics and Fluid Dynamics, Naval Research Laboratory, Washington, DC 20375 (United States); Zalesak, S. T. [Berkeley Research Associates, Beltsville, Maryland 20705 (United States); Iwamoto, Y. [Ehime University, Matsuyama, Ehime Pref. 790-8577 (Japan)

    2016-05-15

    Stagnation of a cold plasma streaming to the center or axis of symmetry via an expanding accretion shock wave is ubiquitous in inertial confinement fusion (ICF) and high-energy-density plasma physics, the examples ranging from plasma flows in x-ray-generating Z pinches [Maron et al., Phys. Rev. Lett. 111, 035001 (2013)] to the experiments in support of the recently suggested concept of impact ignition in ICF [Azechi et al., Phys. Rev. Lett. 102, 235002 (2009); Murakami et al., Nucl. Fusion 54, 054007 (2014)]. Some experimental evidence indicates that stagnation via an expanding shock wave is stable, but its stability has never been studied theoretically. We present such analysis for the stagnation that does not involve a rarefaction wave behind the expanding shock front and is described by the classic ideal-gas Noh solution in spherical and cylindrical geometry. In either case, the stagnated flow has been demonstrated to be stable, initial perturbations exhibiting a power-law, oscillatory or monotonic, decay with time for all the eigenmodes. This conclusion has been supported by our simulations done both on a Cartesian grid and on a curvilinear grid in spherical coordinates. Dispersion equation determining the eigenvalues of the problem and explicit formulas for the eigenfunction profiles corresponding to these eigenvalues are presented, making it possible to use the theory for hydrocode verification in two and three dimensions.

  2. Stability of stagnation via an expanding accretion shock wave

    Science.gov (United States)

    Velikovich, A. L.; Murakami, M.; Taylor, B. D.; Giuliani, J. L.; Zalesak, S. T.; Iwamoto, Y.

    2016-05-01

    Stagnation of a cold plasma streaming to the center or axis of symmetry via an expanding accretion shock wave is ubiquitous in inertial confinement fusion (ICF) and high-energy-density plasma physics, the examples ranging from plasma flows in x-ray-generating Z pinches [Maron et al., Phys. Rev. Lett. 111, 035001 (2013)] to the experiments in support of the recently suggested concept of impact ignition in ICF [Azechi et al., Phys. Rev. Lett. 102, 235002 (2009); Murakami et al., Nucl. Fusion 54, 054007 (2014)]. Some experimental evidence indicates that stagnation via an expanding shock wave is stable, but its stability has never been studied theoretically. We present such analysis for the stagnation that does not involve a rarefaction wave behind the expanding shock front and is described by the classic ideal-gas Noh solution in spherical and cylindrical geometry. In either case, the stagnated flow has been demonstrated to be stable, initial perturbations exhibiting a power-law, oscillatory or monotonic, decay with time for all the eigenmodes. This conclusion has been supported by our simulations done both on a Cartesian grid and on a curvilinear grid in spherical coordinates. Dispersion equation determining the eigenvalues of the problem and explicit formulas for the eigenfunction profiles corresponding to these eigenvalues are presented, making it possible to use the theory for hydrocode verification in two and three dimensions.

  3. Experimental performance of a piston expander in a small- scale organic Rankine cycle

    Science.gov (United States)

    Oudkerk, J. F.; Dickes, R.; Dumont, O.; Lemort, V.

    2015-08-01

    Volumetric expanders are suitable for more and more applications in the field of micro- and small-scale power system as waster heat recovery or solar energy. This paper present an experimental study carried out on a swatch-plate piston expander. The expander was integrated into an ORC test-bench using R245fa. The performances are evaluated in term of isentropic efficiency and filling factor. The maximum efficiency and power reached are respectively 53% and 2 kW. Inside cylinder pressure measurements allow to compute mechanical efficiency and drown P-V diagram. A semi-empirical simulation model is then proposed, calibrated and used to analyse the different sources of losses.

  4. Expanded clinical spectrum of enhanced S-cone syndrome

    NARCIS (Netherlands)

    Yzer, Suzanne; Barbazetto, Irene; Allikmets, Rando; van Schooneveld, Mary J.; Bergen, Arthur; Tsang, Stephen H.; Jacobson, Samuel G.; Yannuzzi, Lawrence A.

    2013-01-01

    New funduscopic findings in patients with enhanced S-cone syndrome (ESCS) may help clinicians in diagnosing this rare autosomal recessive retinal dystrophy. To expand the clinical spectrum of ESCS due to mutations in the NR2E3 gene. Retrospective, noncomparative case series of 31 patients examined

  5. Use of retrievable self-expanding stent in treating childhood benign oesophageal stricture

    International Nuclear Information System (INIS)

    Yu Juming; Fan Guoping; Zhong Weixing; Zhu Ming

    2007-01-01

    Objective: To evaluate the methods and effect of retrievable self-expanding esophageal stent in treating benign esophageal stenosis of children. Methods: The covered retrievable expandable nitinol stents were placed in 10 children with corrosive esophageal stenosis and post-anastomotic stenosis, age ranged from 2 to 12 years, the dysphagia scores were 3, Barium esophagography was taken before the use of retrievable stent. Results: The stents were placed safely in all patients without complications and were successfully removed after all. After the stent placement, all patients could take solid food without dysphagia. During 6 to 12 months follow-up after the stent removal, all children could eat satisfactorily with the dysphagia score as 0. Conclusion: The use of covered retrievable expandable stent is effective and safe in treating childhood benign esophageal stenosis. (authors)

  6. Expanding beyond individualism: Engaging critical perspectives on occupation.

    Science.gov (United States)

    Gerlach, Alison J; Teachman, Gail; Laliberte-Rudman, Debbie; Aldrich, Rebecca M; Huot, Suzanne

    2018-01-01

    Perspectives that individualize occupation are poorly aligned with socially responsive and transformative occupation-focused research, education, and practice. Their predominant use in occupational therapy risks the perpetuation, rather than resolution, of occupational inequities. In this paper, we problematize taken-for-granted individualistic analyses of occupation and illustrate how critical theoretical perspectives can reveal the ways in which structural factors beyond an individual's immediate control and environment shape occupational possibilities and occupational engagement. Using a critically reflexive approach, we draw on three distinct qualitative research studies to examine the potential of critical theorizing for expanding beyond a reliance on individualistic analyses and practices. Our studies highlight the importance of addressing the socio-historical and political contexts of occupation and demonstrate the contribution of critical perspectives to socially responsive occupational therapy. In expanding beyond individualistic analyses of occupation, critical perspectives advance research and practices towards addressing socio-political mediators of occupational engagement and equity.

  7. Wiggler magnetic field assisted third harmonic generation in expanding clusters

    Science.gov (United States)

    Vij, Shivani

    2018-04-01

    A simple theoretical model is constructed to study the wiggler magnetic field assisted third harmonic generation of intense short pulse laser in a cluster in its expanding phase. The ponderomotive force of laser causes density perturbations in cluster electron density which couples with wiggler magnetic field to produce a nonlinear current that generates transverse third harmonic. An intense short pulse laser propagating through a gas embedded with atomic clusters, converts it into hot plasma balls via tunnel ionization. Initially, the electron plasma frequency inside the clusters ω pe > \\sqrt{3}{ω }1 (with ω 1 being the frequency of the laser). As the cluster expands under Coulomb force and hydrodynamic pressure, ω pe decreases to \\sqrt{3}{ω }1. At this time, there is resonant enhancement in the efficiency of the third harmonic generation. The efficiency of third harmonic generation is enhanced due to cluster plasmon resonance and by phase matching due to wiggler magnetic field. The effect of cluster size on the expansion rate is studied to observe that the clusters of different radii would expand differently. The impact of laser intensity and wiggler magnetic field on the efficiency of third harmonic generation is also explored.

  8. Basic Study on Engine with Scroll Compressor and Expander

    Science.gov (United States)

    Morishita, Etsuo; Kitora, Yoshihisa; Nishida, Mitsuhiro

    Scroll compressors are becoming popular in air conditioning and refrigeration. This is primarily due to their higher efficiency and low noise/vibration characteristics. The scroll principle can be applied also to the steam expander and the Brayton cycle engine,as shown in the past literature. The Otto cycle spark-ignition engine with a scroll compressor and expander is studied in this report. The principle and basic structure of the scroll engine are explained,and the engine characteristic are calculated based on the idealized cycles and processes. A prototype model has been proposed and constructed. The rotary type engine has always had a problem with sealing. The scroll engine might overcome this shortcoming with its much lower rubbing speed compared to its previous counterparts,and is therefore worth investigating.

  9. Momentum-space representation of Green's functions with modified dispersion on ultrastatic space-time

    International Nuclear Information System (INIS)

    Rinaldi, Massimiliano

    2007-01-01

    We consider Green's functions associated to a scalar field propagating on a curved, ultrastatic background, in the presence of modified dispersion relations. The usual proper-time DeWitt-Schwinger procedure to obtain a series representation of Green's functions is doomed to failure because of higher order spatial derivatives in the Klein-Gordon operator. We show how to overcome this difficulty by considering a preferred frame, associated to a unit timelike vector. With respect to this frame, we can express Green's functions as an integral over all frequencies of a space-dependent function. The latter can be expanded in momentum space, as a series with geometric coefficients similar to the DeWitt-Schwinger ones. By integrating over all frequencies, we finally find the expansion of Green's function up to four derivatives of the metric tensor. The relation with the proper-time formalism is also discussed

  10. Tear Gas, Expanding Bullets and Plain-Clothed Personnel

    DEFF Research Database (Denmark)

    Wiesener, Cornelius Rust

    2017-01-01

    This article examines the interplay between human rights law and humanitarian law in relation to riot control agents (such as tear gas), expanding bullets and plain-clothed forces. While outlawed under humanitarian law, they are widely used by police in peace time and not subject to similar bans...

  11. Expanding Library Support of Faculty Research: Exploring Readiness

    Science.gov (United States)

    Brown, Jeanne M.; Tucker, Cory

    2013-01-01

    The changing research and information environment requires a reexamination of library support for research. This study considers research-related attitudes and practices to identify elements indicating readiness or resistance to expanding the library's role in research support. A survey of faculty conducted at the University of Nevada Las Vegas…

  12. Assessing Community Needs for Expanding Environmental Education Programming

    Science.gov (United States)

    Hintz, Carly J.; Lackey, Brenda K.

    2017-01-01

    Based on increased demand for educational programming, leadership at Schmeeckle Reserve, a campus natural area in Stevens Point, WI explored the needs for expanded environmental education efforts. In 2014, a three-phased needs assessment framework was employed to explore educational programming offered in the community. Results from interviews and…

  13. Expander graphs in pure and applied mathematics

    OpenAIRE

    Lubotzky, Alexander

    2012-01-01

    Expander graphs are highly connected sparse finite graphs. They play an important role in computer science as basic building blocks for network constructions, error correcting codes, algorithms and more. In recent years they have started to play an increasing role also in pure mathematics: number theory, group theory, geometry and more. This expository article describes their constructions and various applications in pure and applied mathematics.

  14. Exploiting lipopolysaccharide-induced deformation of lipid bilayers to modify membrane composition and generate two-dimensional geometric membrane array patterns

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Peter G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Swingle, Kirstie L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Univ. of New Mexico, Albuquerque, NM (United States); Paxton, Walter F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nogan, John J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stromberg, Loreen R. [Univ. of New Mexico, Albuquerque, NM (United States); Firestone, Millicent A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mukundan, Harshini [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); New Mexico Consortium, Los Alamos, NM (United States); Montaño, Gabriel A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-05-27

    Supported lipid bilayers have proven effective as model membranes for investigating biophysical processes and in development of sensor and array technologies. The ability to modify lipid bilayers after their formation and in situ could greatly advance membrane technologies, but is difficult via current state-of-the-art technologies. Here we demonstrate a novel method that allows the controlled post-formation processing and modification of complex supported lipid bilayer arrangements, under aqueous conditions. We exploit the destabilization effect of lipopolysaccharide, an amphiphilic biomolecule, interacting with lipid bilayers to generate voids that can be backfilled to introduce desired membrane components. We further demonstrate that when used in combination with a single, traditional soft lithography process, it is possible to generate hierarchically-organized membrane domains and microscale 2-D array patterns of domains. Significantly, this technique can be used to repeatedly modify membranes allowing iterative control over membrane composition. This approach expands our toolkit for functional membrane design, with potential applications for enhanced materials templating, biosensing and investigating lipid-membrane processes.

  15. Safety of endoscopic removal of self-expandable stents after treatment of benign esophageal diseases

    NARCIS (Netherlands)

    van Halsema, Emo E.; Wong Kee Song, Louis M.; Baron, Todd H.; Siersema, Peter D.; Vleggaar, Frank P.; Ginsberg, Gregory G.; Shah, Pari M.; Fleischer, David E.; Ratuapli, Shiva K.; Fockens, Paul; Dijkgraaf, Marcel G. W.; Rando, Giacomo; Repici, Alessandro; van Hooft, Jeanin E.

    2013-01-01

    Temporary placement of self-expandable stents has been increasingly used for the management of benign esophageal diseases. To evaluate the safety of endoscopic removal of esophageal self-expandable stents placed for the treatment of benign esophageal diseases. Multicenter retrospective study. Six

  16. Evidence for a modifier of onset age in Huntington disease linked to the HD gene in 4p16

    Science.gov (United States)

    Djoussé, Luc; Knowlton, Beth; Hayden, Michael R.; Almqvist, Elisabeth W.; Brinkman, Ryan R.; Ross, Christopher A.; Margolis, Russel L.; Rosenblatt, Adam; Durr, Alexandra; Dode, Catherine; Morrison, Patrick J.; Novelletto, Andrea; Frontali, Marina; Trent, Ronald J. A.; McCusker, Elizabeth; Gómez-Tortosa, Estrella; Mayo Cabrero, David; Jones, Randi; Zanko, Andrea; Nance, Martha; Abramson, Ruth K.; Suchowersky, Oksana; Paulsen, Jane S.; Harrison, Madaline B.; Yang, Qiong; Cupples, L. Adrienne; Mysore, Jayalakshmi; Gusella, James F.; MacDonald, Marcy E.

    2007-01-01

    Huntington disease (HD) is a neurodegenerative disorder caused by the abnormal expansion of CAG repeats in the HD gene on chromosome 4p16.3. A recent genome scan for genetic modifiers of age at onset of motor symptoms (AO) in HD suggests that one modifier may reside in the region close to the HD gene itself. We used data from 535 HD participants of the New England Huntington cohort and the HD MAPS cohort to assess whether AO was influenced by any of the three markers in the 4p16 region: MSX1 (Drosophila homeo box homologue 1, formerly known as homeo box 7, HOX7), Δ2642 (within the HD coding sequence), and BJ56 (D4S127). Suggestive evidence for an association was seen between MSX1 alleles and AO, after adjustment for normal CAG repeat, expanded repeat, and their product term (model P value 0.079). Of the variance of AO that was not accounted for by HD and normal CAG repeats, 0.8% could be attributed to the MSX1 genotype. Individuals with MSX1 genotype 3/3 tended to have younger AO. No association was found between Δ2642 (P=0.44) and BJ56 (P=0.73) and AO. This study supports previous studies suggesting that there may be a significant genetic modifier for AO in HD in the 4p16 region. Furthermore, the modifier may be present on both HD and normal chromosomes bearing the 3 allele of the MSX1 marker. PMID:15029481

  17. Preparation and Characterization of Dabco (1,4-Diazabicyclo [2.2.2]octane) modified bentonite: Application for Congo red removal

    Science.gov (United States)

    Taher, Tarmizi; Rohendi, Dedi; Mohadi, Risfidian; Lesbani, Aldes

    2018-01-01

    Natural bentonite provided from Sarolangun deposit was modified with 1,4-Diazabicyclo[2.2.2]octane (Dabco) to form a new class of porous material. Prior further modification, the natural bentonite was cleaned up and activated by NaCl to remove the impurities and increase the bentonite nature. Dabco modified bentonite (Dabco-bent) was prepared by exchanging the inorganic cation placed in the interlayer space of the montmorillonite mineral structure with the 0.01 M Dabco1+ at pH 6. The modified bentonite products were characterized using X-Ray powder diffraction and FT-IR to monitor the change of the bentonite crystallinity and function group due to the modification process. The XRD result confirmed that during the modification process, the d(001) of smectite peak at 2q around 6° was shifted. After the modification, the d(001) reflection of the montmorillonite interlayer was shifted 0.36° to the left indicating that the interlayer space of the montmorillonite has been expanded during the modification process. The FTIR spectra of Dabco modified bentonite exhibit no significantly different with the host bentonite. However, the presence of the new band at the wavenumber around 3000 and 2800 cm-1 indicates that the Dabco molecule has been successfully inserted to the bentonite molecule. The Congo red adsorption experiment was performed onto Dabco-bent product by batch technique. The experiment data described that kinetic model for Congo red adsorption onto Dabco-bent was adequately followed the second-order kinetic model and well described by Freundlich adsorption isotherm model.

  18. Farmer's market, demonstration gardens, and research projects expand outreach of Extension Master Gardeners

    Science.gov (United States)

    Pamela J. Bennett; Ellen M. Bauske; Alison Stoven O' Connor; Jean Reeder; Carol Busch; Heidi A. Kratsch; Elizabeth Leger; Angela O' Callaghan; Peter J. Nitzche; Jim Downer

    2013-01-01

    Extension Master Gardener (EMG) volunteers are central to expanding the outreach and engagement of extension staff. A workshop format was used at the Annual Conference of the American Society for Horticultural Science on 31 July 2012 in Miami, FL to identify successful management techniques and projects that expand EMG volunteer outreach, leading to increased extension...

  19. Gravitational mass in an expanding universe

    International Nuclear Information System (INIS)

    Sannan, S.

    1986-01-01

    A test for the Hawking definition of mass is given in a Tolman--Bondi model that asymptotically approaches the open Friedmann universe. An expanding universe filled with dustlike matter of zero pressure is considered. The matter distribution is spherically symmetric but nonhomogeneous. With appropriate boundary conditions, the calculation yields a finite and nonzero value for the Hawking mass, measured as a deviation from a ''renormalized'' zero mass in the unperturbed Friedmann model. These boundary conditions are more restrictive than those found for a model with gravitational radiation

  20. Evaluation of anti-migration properties of biliary covered self-expandable metal stents.

    Science.gov (United States)

    Minaga, Kosuke; Kitano, Masayuki; Imai, Hajime; Harwani, Yogesh; Yamao, Kentaro; Kamata, Ken; Miyata, Takeshi; Omoto, Shunsuke; Kadosaka, Kumpei; Sakurai, Toshiharu; Nishida, Naoshi; Kudo, Masatoshi

    2016-08-14

    To assess anti-migration potential of six biliary covered self-expandable metal stents (C-SEMSs) by using a newly designed phantom model. In the phantom model, the stent was placed in differently sized holes in a silicone wall and retracted with a retraction robot. Resistance force to migration (RFM) was measured by a force gauge on the stent end. Radial force (RF) was measured with a RF measurement machine. Measured flare structure variables were the outer diameter, height, and taper angle of the flare (ODF, HF, and TAF, respectively). Correlations between RFM and RF or flare variables were analyzed using a linear correlated model. Out of the six stents, five stents were braided, the other was laser-cut. The RF and RFM of each stent were expressed as the average of five replicate measurements. For all six stents, RFM and RF decreased as the hole diameter increased. For all six stents, RFM and RF correlated strongly when the stent had not fully expanded. This correlation was not observed in the five braided stents excluding the laser cut stent. For all six stents, there was a strong correlation between RFM and TAF when the stent fully expanded. For the five braided stents, RFM after full stent expansion correlated strongly with all three stent flare structure variables (ODF, HF, and TAF). The laser-cut C-SEMS had higher RFMs than the braided C-SEMSs regardless of expansion state. RF was an important anti-migration property when the C-SEMS did not fully expand. Once fully expanded, stent flare structure variables plays an important role in anti-migration.

  1. Self-Expandable Metallic Stent Placement for the Palliation of Esophageal Cancer.

    Science.gov (United States)

    Kim, Kun Yung; Tsauo, Jiaywei; Song, Ho Young; Kim, Pyeong Hwa; Park, Jung Hoon

    2017-07-01

    Esophageal stents have been used to palliate patients with dysphagia caused by esophageal cancer. Early rigid plastic prostheses have been associated with a high risk of complications. However, with the development of self-expanding stents, it has developed into a widely accepted method for treating malignant esophageal strictures and esophagorespiratory fistulas (ERFs). The present review covers various aspects of self-expanding metallic stent placement for palliating esophageal cancer, including its types, placement procedures, indications, contraindications, complications, and some of innovations that will become available in the future. © 2017 The Korean Academy of Medical Sciences.

  2. Expandable esophageal metallic stents coating with silicone rubber: An experimental study in rabbits

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Han, Young Min; Son, Myung Hee; Kim, Jong Soo; Choi, Ki Chul; Kuh, Ja Hong; Chae, Soo Wan [Chonbuk National University Medical School, Chonju (Korea, Republic of); Kim, Hak Nam [Chungju Lee Rha Hospital, Chungju (Korea, Republic of)

    1990-10-15

    To determine the effect of the expandable esophageal metallic stents on the esophagus, we constructed an expandable metallic stent. It was stainless steel wire formed in a zig-zag pattern in fully expanded diameter. Twenty stents were introduced in the normal esophagus through a 8.5 French-teflon sheath in 10 rabbits for 1 week to 12 weeks. Three out of the 20 stents migrated slightly. At 1 week after the placement of the stent, the mucosa partly revealed pressure necrosis and some regeneration, the muscle layer below the stent wires found compressed and thinned. At 8 weeks, the mucosa showed complete regeneration, and the stent wires were found covered by fibrous tissue.

  3. Optimization design of turbo-expander gas bearing for a 500W helium refrigerator

    Science.gov (United States)

    Li, S. S.; Fu, B.; Y Zhang, Q.

    2017-12-01

    Turbo-expander is the core machinery of the helium refrigerator. Bearing as the supporting element is the core technology to impact the design of turbo-expander. The perfect design and performance study for the gas bearing are essential to ensure the stability of turbo-expander. In this paper, numerical simulation is used to analyze the performance of gas bearing for a 500W helium refrigerator turbine, and the optimization design of the gas bearing has been completed. And the results of the gas bearing optimization have a guiding role in the processing technology. Finally, the turbine experiments verify that the gas bearing has good performance, and ensure the stable operation of the turbine.

  4. Modeling and analysis of scroll compressor conversion into expander for Rankine cycles

    Energy Technology Data Exchange (ETDEWEB)

    Oralli, E.; Dincer, I.; Zamfirescu, C. [Faculty of Engineering and Applied Science, University of Ontario Institute of Technology (Canada)], E-mail: Emre.Oralli@uoit.ca, email: Ibrahim.Dincer@uoit.ca, email: Calin.Zamfirescu@uoit.ca

    2011-07-01

    With the current push towards the use of sustainable energies, low power heat generation systems are shifting towards sustainable heat sources such as geothermal, solar, industrial waste and cogeneration energy. The aim of this paper is to investigate the use of a scroll expander for power generation using the Rankine cycle. A parametric study was carried out on a refrigeration scroll compressor to determine the impact of geometry, working fluid, and operating conditions on the efficiency of the Rankine heat engine. In addition modifications were made to the expander to optimize its operation. Results showed that organic fluids should be used at saturated conditions, that decreasing the temperature of the condenser leads to an increased thermal efficiency of ORC and that the designed radius is an optimum value. This study highlighted the impacts of geometric and thermodynamic parameters on scroll expanders.

  5. The Expanded Food and Nutrition Education Program (EFNEP)

    Science.gov (United States)

    National Institute of Food and Agriculture, 2010

    2010-01-01

    Obesity, poor health, and limited physical activity are major health concerns. The Expanded Food and Nutrition Education Program (EFNEP) improves the health and well-being of limited resource families and youth. Additionally, EFNEP leads to public savings. Research shows that better health is associated with reduced health care costs, less…

  6. An approach to tracheostomy in a patient with an expandable metallic tracheal stent.

    Science.gov (United States)

    Madden, Brendan P; Sheth, Abhijat

    2005-09-01

    With increasing use of expandable metallic stents to manage patients with a variety of endobronchial pathologies, some will have a subsequent need for tracheostomy insertion. We describe a successful technique to insert a tracheostomy using rigid and fibre-optic bronchoscopy in a patient who had an 8 cm expandable metallic tracheal stent deployed previously on account of tracheomalacia.

  7. Reconstructive Surgery of Extensive Face and Neck Burn Scars Using Tissue Expanders

    OpenAIRE

    Ashab Yamin, Mohammad Reza; Mozafari, Naser; Mozafari, Mohadase; Razi, Zahra

    2015-01-01

    BACKGROUND Neck reconstruction is considered as one of the most important surgeries in cosmetic and reconstructive surgery.?The present study aimed to assess the results of reconstructive surgery of extensive face and neck burning scars using tissue expanders. METHODS This descriptive prospective study was conducted on 36 patients with extensive burning scars on the neck and face. Operation for tissue expander insertion was performed and tissue distension started two or three weeks later, dep...

  8. The bibliometric behaviour of an expanding specialisation of medical research

    Energy Technology Data Exchange (ETDEWEB)

    Thelwall, M.; Levitt, J.

    2016-07-01

    This study investigates macular disease research and cataract research, which are both specialisations of Ophthalmology. Macular disease and cataracts are amongst the three leading causes of blindness in the world. Macular research expanded between 1992 and 2006 in that the proportion of Ophthalmology articles classified as macular increased by over 300% in that period. By contrast, during that same period the proportion of Ophthalmology articles classified as ‘cataract’ decreased by over 20%. This study investigates the bibliometric differences between the rapidly expanding specialisation of ‘macular’ and the slightly contracting specialisation of ‘cataract’. Our rationale for investigating these bibliometric differences is that previous researchers have suggested that articles in expanding specialisations are likely to be more highly cited than articles in relatively static specialisations, and it seems important, when comparing specialisations, to try to ensure that articles in a relatively static specialisation are not penalised. This study first identifies substantial macro-level bibliometric differences between the two specialisations and then gauges the extent to which these differences were associated with the expansion of Macular compared with Cataract. The initial investigation uses coarse-grained delineations of the specialisation, formed from search terms frequently associated with macular (and cataract). It finds that articles in the relatively expanding specialisation were substantially more highly cited and that these differences were associated with the expansion of the specialisation rather than the size of the specialisation (the Matthew effect). A major limitation of this study is that its coarse-grained delineation of specialisations fails to identify substantial numbers of articles in the specialisation. A more fine-grained delineation using PubMed’s Medical Subject Headings (MESH) has been piloted and additional articles

  9. Oversizing and Restenosis with Self-Expanding Stents in Iliofemoral Arteries

    International Nuclear Information System (INIS)

    Saguner, Ardan M.; Traupe, Tobias; Räber, Lorenz; Hess, Nina; Banz, Yara; Saguner, Arhan R.; Diehm, Nicolas; Hess, Otto M.

    2012-01-01

    Purpose: Uncoated self-expanding nitinol stents (NS) are commonly oversized in peripheral arteries. In current practice, 1-mm oversizing is recommended. Yet, oversizing of NS may be associated with increased restenosis. To provide further evidence, NS were implanted in porcine iliofemoral arteries with a stent-to-artery-ratio between 1.0 and 2.3. Besides conventional uncoated NS, a novel self-expanding NS with an antiproliferative titanium-nitride-oxide (TiNOX) coating was tested for safety and efficacy. Methods: Ten uncoated NS and six TiNOX-coated NS (5–6 mm) were implanted randomly in the iliofemoral artery of six mini-pigs. After implantation, quantitative angiography (QA) was performed for calculation of artery and minimal luminal diameter. Follow-up was performed by QA and histomorphometry after 5 months. Results: Stent migration, stent fracture, or thrombus formation were not observed. All stents were patent at follow-up. Based on the location of the stent (iliac/femoral) and the stent-to-artery-ratio, stent segments were divided into “normal-sized” (stent-to-artery-ratio < 1.4, n = 12) and “oversized” (stent-to-artery-ratio ≥ 1.4, n = 9). All stent segments expanded to their near nominal diameter during follow-up. Normal-sized stent segments increased their diameter by 6% and oversized segments by 29%. A significant correlation between oversizing and restenosis by both angiography and histomorphometry was observed. Restenosis rates were similar for uncoated NS and TiNOX-coated NS. Conclusions: TiNOX-coated NS are as safe and effective as uncoated NS in the porcine iliofemoral artery. All stents further expand to near their nominal diameter during follow-up. Oversizing is linearly and positively correlated with neointimal proliferation and restenosis, which may not be reduced by TiNOX-coating.

  10. Optimizing the performance of small-scale organic Rankine cycle that utilizes a single-screw expander

    International Nuclear Information System (INIS)

    Ziviani, D.; Gusev, S.; Lecompte, S.; Groll, E.A.; Braun, J.E.; Horton, W.T.; Broek, M. van den; De Paepe, M.

    2017-01-01

    Highlights: • A total of 102 steady-state points with R245fa and SES336 have been collected. • R245fa led to 10% higher power output despite lower expander isentropic efficiency. • The ORC running with SES36 presented a better matching between expander and cycle. • The theoretical matching between expander volume ratio and cycle efficiency is determined. • Steady-state performance maps are used to build a feed-forward controller. - Abstract: This paper deals with the operation and optimization of a down-scaled industrial organic Rankine cycle (ORC) for low-grade waste heat recovery. The system is a sub-critical regenerative ORC with a nominal power output of 11 kW. The ORC unit has been assembled using off-the-shelf components including three identical plate heat exchangers, a liquid receiver, a multi-stage centrifugal pump and a single-screw compressor adapted to operate as an expander. The experimental results are used to evaluate the influence of the expander performance on the behavior of the ORC system at nominal and part-load conditions. The matching between the volumetric expander and the system operating conditions is also analyzed. Results showed that in the case of SES36, both the expander efficiency and system performance were maximized for a pressure ratio between 7 and 9. In the case of R245fa, while the system efficiency achieved values similar to SES36, but the expander maximum isentropic efficiency was 17% lower. Two analyses are carried out to optimize the operation of the ORC unit with R245fa. At first, the insights gained by analyzing the experimental data are used to evaluate the theoretical matching between volumetric expander and the system maximum efficiency in terms of the Second Law of thermodynamics. Secondly, a control-oriented steady-state cycle model based on empirical correlations calibrated on the experimental results is developed. The model is used to implement a feed-forward control strategy based on predetermined steady

  11. Surgical outcomes and nipple projection using the modified skate flap for nipple-areolar reconstruction in a series of 422 implant reconstructions.

    Science.gov (United States)

    Zhong, Toni; Antony, Anu; Cordeiro, Peter

    2009-05-01

    Numerous techniques have been used in an attempt to achieve long-term nipple projection following nipple-areolar reconstruction (NAR). A common setback, however, is the diminution of projection over time; this phenomenon is particularly evident following implant based breast reconstruction. The purpose of this report was thus to evaluate surgical outcomes and long-term nipple projection with the use of "modified skate flap" technique in exclusively implant based postmastectomy reconstructions. A retrospective review was performed for the period between 1993 and 2007. All consecutive patients with 2-staged tissue expander/implant reconstructions followed by NAR using the modified skate flap technique performed by the senior author (P.C.) were identified in a prospectively maintained breast reconstruction database. Only patients with a minimum of 1-year follow-up were included in the study. Patients with a history of irradiation to the breast were excluded from nipple projection assessment. Clinical outcome measurements included long-term nipple projection as well as incidence of complications from the NAR procedure using the modified skate flap technique. Over the 15-year study period, 475 patients underwent 2-staged tissue expander/implant reconstruction followed by NAR using the modified skate flap technique. Of these, there was a total of 292 patients with the minimum requirement of 1-year follow-up post NAR (61% follow-up rate). The total number of reconstructed nipple areolar complexes evaluated in this series was 422 (130 bilateral and 162 unilateral NAR). Forty patients (28 unilateral and 12 bilateral NAR) who received radiation to their breasts were excluded from nipple projection assessment. At a median follow-up of 44 months (range: 12-84 months), mean nipple projection was 2.5 mm (range: 1-4 mm). Minor complications occurred in 7.2% of the patients (n = 292). Skin graft donor site dehiscence was the most common complication (3.1%) followed by partial skin

  12. Expanding the Enzyme Universe: Accessing Non-Natural Reactions by Mechanism-Guided Directed Evolution

    Science.gov (United States)

    Renata, Hans; Wang, Z. Jane

    2015-01-01

    High selectivities and exquisite control over reaction outcomes entice chemists to use biocatalysts in organic synthesis. However, many useful reactions are not accessible because they are not in nature’s known repertoire. We will use this review to outline an evolutionary approach to engineering enzymes to catalyze reactions not found in nature. We begin with examples of how nature has discovered new catalytic functions and how such evolutionary progressions have been recapitulated in the laboratory starting from extant enzymes. We then examine non-native enzyme activities that have been discovered and exploited for chemical synthesis, emphasizing reactions that do not have natural counterparts. The new functions have mechanistic parallels to the native reaction mechanisms that often manifest as catalytic promiscuity and the ability to convert from one function to the other with minimal mutation. We present examples of how non-natural activities have been improved by directed evolution, mimicking the process used by nature to create new catalysts. Examples of new enzyme functions include epoxide opening reactions with non-natural nucleophiles catalyzed by a laboratory-evolved halohydrin dehalogenase, cyclopropanation and other carbene transfer reactions catalyzed by cytochrome P450 variants, and non-natural modes of cyclization by a modified terpene synthase. Lastly, we describe discoveries of non-native catalytic functions that may provide future opportunities for expanding the enzyme universe. PMID:25649694

  13. Feathermoss and epiphytic Nostoc cooperate differently: expanding the spectrum of plant–cyanobacteria symbiosis

    Science.gov (United States)

    Warshan, Denis; Espinoza, Josh L; Stuart, Rhona K; Richter, R Alexander; Kim, Sea-Yong; Shapiro, Nicole; Woyke, Tanja; C Kyrpides, Nikos; Barry, Kerrie; Singan, Vasanth; Lindquist, Erika; Ansong, Charles; Purvine, Samuel O; M Brewer, Heather; Weyman, Philip D; Dupont, Christopher L; Rasmussen, Ulla

    2017-01-01

    Dinitrogen (N2)-fixation by cyanobacteria in symbiosis with feathermosses is the primary pathway of biological nitrogen (N) input into boreal forests. Despite its significance, little is known about the cyanobacterial gene repertoire and regulatory rewiring needed for the establishment and maintenance of the symbiosis. To determine gene acquisitions and regulatory changes allowing cyanobacteria to form and maintain this symbiosis, we compared genomically closely related symbiotic-competent and -incompetent Nostoc strains using a proteogenomics approach and an experimental set up allowing for controlled chemical and physical contact between partners. Thirty-two gene families were found only in the genomes of symbiotic strains, including some never before associated with cyanobacterial symbiosis. We identified conserved orthologs that were differentially expressed in symbiotic strains, including protein families involved in chemotaxis and motility, NO regulation, sulfate/phosphate transport, and glycosyl-modifying and oxidative stress-mediating exoenzymes. The physical moss–cyanobacteria epiphytic symbiosis is distinct from other cyanobacteria–plant symbioses, with Nostoc retaining motility, and lacking modulation of N2-fixation, photosynthesis, GS-GOGAT cycle and heterocyst formation. The results expand our knowledge base of plant–cyanobacterial symbioses, provide a model of information and material exchange in this ecologically significant symbiosis, and suggest new currencies, namely nitric oxide and aliphatic sulfonates, may be involved in establishing and maintaining the cyanobacteria–feathermoss symbiosis. PMID:28800136

  14. Feathermoss and epiphytic Nostoc cooperate differently: expanding the spectrum of plant-cyanobacteria symbiosis.

    Science.gov (United States)

    Warshan, Denis; Espinoza, Josh L; Stuart, Rhona K; Richter, R Alexander; Kim, Sea-Yong; Shapiro, Nicole; Woyke, Tanja; C Kyrpides, Nikos; Barry, Kerrie; Singan, Vasanth; Lindquist, Erika; Ansong, Charles; Purvine, Samuel O; M Brewer, Heather; Weyman, Philip D; Dupont, Christopher L; Rasmussen, Ulla

    2017-12-01

    Dinitrogen (N 2 )-fixation by cyanobacteria in symbiosis with feathermosses is the primary pathway of biological nitrogen (N) input into boreal forests. Despite its significance, little is known about the cyanobacterial gene repertoire and regulatory rewiring needed for the establishment and maintenance of the symbiosis. To determine gene acquisitions and regulatory changes allowing cyanobacteria to form and maintain this symbiosis, we compared genomically closely related symbiotic-competent and -incompetent Nostoc strains using a proteogenomics approach and an experimental set up allowing for controlled chemical and physical contact between partners. Thirty-two gene families were found only in the genomes of symbiotic strains, including some never before associated with cyanobacterial symbiosis. We identified conserved orthologs that were differentially expressed in symbiotic strains, including protein families involved in chemotaxis and motility, NO regulation, sulfate/phosphate transport, and glycosyl-modifying and oxidative stress-mediating exoenzymes. The physical moss-cyanobacteria epiphytic symbiosis is distinct from other cyanobacteria-plant symbioses, with Nostoc retaining motility, and lacking modulation of N 2 -fixation, photosynthesis, GS-GOGAT cycle and heterocyst formation. The results expand our knowledge base of plant-cyanobacterial symbioses, provide a model of information and material exchange in this ecologically significant symbiosis, and suggest new currencies, namely nitric oxide and aliphatic sulfonates, may be involved in establishing and maintaining the cyanobacteria-feathermoss symbiosis.

  15. Debye's length in expanding quark-gluon plasma

    International Nuclear Information System (INIS)

    Bialas, A.

    1988-06-01

    The screening properties of an abelian quark-gluon plasma and boost invariantly expanding in a given direction, are discussed. The expansion results in anisotropic screening. At early stages of the process, the Debye length along the direction of the expansion is reduced by a factor of about 2, relative to static calculations. This may have important consequences for the J/ψ production rate. 12 refs., 2 figs., 1 tab. (author)

  16. Gravitational Clustering of Galaxies in an Expanding Universe ...

    Indian Academy of Sciences (India)

    2006-12-08

    Dec 8, 2006 ... Abstract. We inquire the phenomena of clustering of galaxies in an expanding universe from a theoretical point of view on the basis of ther- modynamics and correlation functions. The partial differential equation is developed both for the point mass and extended mass structures of a two-point correlation ...

  17. Phosphonium modified clay/polyimide nanocomposites

    International Nuclear Information System (INIS)

    Ceylan, Hatice; Çakmakçi, Emrah; Beyler-Çiǧil, Asli; Kahraman, Memet Vezir

    2014-01-01

    In this study, octyltriphenylphosphonium bromide [OTPP-Br] was prepared from the reaction of triphenylphosphine and 1 -bromooctane. The modification of clay was done by ion exchange reaction using OTPP-Br in water medium. Poly(amic acid) was prepared from the reaction of 3,3',4,4'-Benzophenonetetracarboxylic dianhydride (BTDA) and 4,4'-Oxydianiline (ODA). Polyimide(PI)/clay hybrids were prepared by blending of poly(amic acid) and organically modified clay as a type of layered clays. The morphology of the Polyimide/ phosphonium modified clay hybrids was characterized by scanning electron microscopy (SEM). Chemical structures of polyimide and Polyimide/ phosphonium modified clay hybrids were characterized by FTIR. SEM and FTIR results showed that the Polyimide/ phosphonium modified clay hybrids were successfully prepared. Thermal properties of the Polyimide/ phosphonium modified clay hybrids were characterized by thermogravimetric analysis (TGA)

  18. Expanded social fitness and Hamilton's rule for kin, kith, and kind.

    Science.gov (United States)

    Queller, David C

    2011-06-28

    Inclusive fitness theory has a combination of simplicity, generality, and accuracy that has made it an extremely successful way of thinking about and modeling effects on kin. However, there are types of social interactions that, although covered, are not illuminated. Here, I expand the inclusive fitness approach and the corresponding neighbor-modulated approach to specify two other kinds of social selection. Kind selection, which includes greenbeards and many nonadditive games, is where selection depends on an actor's trait having different effects on others depending on whether they share the trait. Kith selection includes social effects that do not require either kin or kind, such as mutualism and manipulation. It involves social effects of a trait that affect a partner, with feedback to the actor's fitness. I derive expanded versions of Hamilton's rule for kith and kind selection, generalizing Hamilton's insight that we can model social selection through a sum of fitness effects, each multiplied by an appropriate association coefficient. Kinship is, thus, only one of the important types of association, but all can be incorporated within an expanded inclusive fitness.

  19. Diagnostic study of multiple double layer formation in expanding RF plasma

    Science.gov (United States)

    Chakraborty, Shamik; Paul, Manash Kumar; Roy, Jitendra Nath; Nath, Aparna

    2018-03-01

    Intensely luminous double layers develop and then expand in size in a visibly glowing RF discharge produced using a plasma source consisting of a semi-transparent cylindrical mesh with a central electrode, in a linear plasma chamber. Although RF discharge is known to be independent of device geometry in the absence of magnetic field, the initiation of RF discharge using such a plasma source results in electron drift and further expansion of the plasma in the vessel. The dynamics of complex plasma structures are studied through electric probe diagnostics in the expanding RF plasma. The measurements made to study the parametric dependence of evolution of double layer structures are analyzed and presented here. The plasma parameter measurements suggest that the complex potential structures initially form with low potential difference between the layers and then gradually expand producing burst oscillations. The present study provides interesting information about the stability of plasma sheath and charge particle dynamics in it that are important to understand the underlying basic sheath physics along with applications in plasma acceleration and propulsion.

  20. Selected properties of the potato snacks expanded in the microwave radiation

    Directory of Open Access Journals (Sweden)

    Mitrus Marcin

    2018-01-01

    Full Text Available The results of measurements of the selected properties of the extruded potato pellets and snacks expanded in the microwave field are presented in the paper. The potato pellets with the addition of the baking soda were prepared with a single screw extruder TS-45. The snacks were obtained by pellets expansion in a conventional microwave oven. The expansion index and the hardness of the pellets and the snacks, as well as, the texture properties of the snacks were evaluated during this study. The results showed that baking soda addition reduced the potato pellet expansion during their extrusion. This was an effect of a smaller thickness of the obtained pellets. The addition of baking soda had positive influence on potato snacks expansion in microwave radiation. The higher content of the soda additive resulted in lower hardness of pellets during cutting tests. The opposite effect was observed during texture measurements of the snacks. The addition of baking soda increased hardness of the expanded snacks. Soda addition lowers crispness and fragilityof the potato snacks expanded in the microwave radiation.

  1. Expanded activity of schools in Serbia: Legal framework and practical experiences

    Directory of Open Access Journals (Sweden)

    Ognjenović Kosovka Đ.

    2012-09-01

    Full Text Available Expanded activities of schools and activities of student cooperatives are important components of the educational process in schools, which are contributing to the improvement of the quality of education and better social inclusion of students. The main objective of this article is to focus on opportunities enabled by the legal framework that supports the realization of expanded activities and activities of student cooperatives in Serbian schools and to compare relevant experiences in Serbia with the practice in neighbouring countries and the old EU Member States. In particular, in this article it is examined to what extent the adoption of entrepreneurial competences through different entrepreneurship development programs contributes to the probability of implementation of additional activities in Serbian schools. For this purpose, the data of the Survey on practising, types and usefulness of expanded activities and activities of student cooperatives are used. This survey was conducted in 2010 at the samples of public primary and secondary schools that executed some sort of additional activities, as well as of schools that did not practice extended activities.

  2. Adsorption of polynuclear aromatic hydrocarbons from aqueous solution: Agrowaste-modified kaolinite vs surfactant modified bentonite

    Directory of Open Access Journals (Sweden)

    E. I. Unuabonah

    2017-01-01

    Full Text Available The adsorption efficiency of a new hybrid clay adsorbent for polynuclear aromatic hydrocarbons (PAHs is compared with known modified clay adsorbents. The new hybrid clay adsorbent (HYCA showed far higher adsorption capacities for the adsorption of various PAH molecules compared with sodium dodecyl sulfate modified and humic acid modified Bentonite clay adsorbents. With the new hybrid clay adsorbent (HYCA, the adsorption of some of the larger PAH molecules was complete in the first 1 h as compared with ≈ 62% and ≈ 76% observed for both humic acid modified and sodium dodecyl sulfate modified Bentonite clay adsorbents respectively. In 24 h adsorption of the PAHs was complete for all adsorbents with HYCA adsorbent showing better efficiency in the removal of the PAH molecules from aqueous solutions. No significant change was observed with increase in time up to 48 h. The adsorption was observed to be more spontaneous with HYCA adsorbent than with either modified Bentonite adsorbents. The enthalpy of adsorption did not follow any specific order and were not consistent for all PAH molecules considered.

  3. Feasibility analysis and performance characteristics investigation of spatial recuperative expander based on organic Rankine cycle for waste heat recovery

    International Nuclear Information System (INIS)

    Han, Yongqiang; Li, Runzhao; Liu, Zhongchang; Tian, Jing; Wang, Xianfeng; Kang, Jianjian

    2016-01-01

    Highlights: • A new concept of spatial recuperative expander for waste heat recovery is proposed. • Simulation model of spatial recuperative expander is established and verified. • The performance characteristics of spatial recuperative expander are investigated. • Comparison between spatial recuperative expander and traditional one is performed. • Spatial recuperative expander achieves better performance than traditional one. - Abstract: This paper proposes a new concept of spatial recuperative expander which injects cold refrigerant during exhaust stroke as a measure of direct contact heat transfer. The commercial simulation tool GT-SUIT 7.4 is employed to model and verify the feasibility of spatial recuperative expander. The research contents are comprised of the following aspects: Firstly, the principles and performance characteristics between traditional reciprocating piston expander and spatial recuperative expander have been investigated. Secondly, the potential of spatial recuperation by adjusting cold refrigerant injection timing has been studied. Thirdly, the relation between expander performance and variable expansion ratio under constant operating condition has been discussed. Fourthly, the thermodynamic performance of spatial recuperative expander under various operating conditions has been examined. The simulation results indicate that: Firstly, the torque per unit mass, thermal efficiency, exergetic efficiency, isentropic efficiency and recuperative efficiency of optimum spatial recuperative expander are 51.00%, 6.74%, 20.79%, 5.68% and 11.36% higher than traditional reciprocating piston expander respectively. Secondly, the cold refrigerant injection timing has little influence on recuperative efficiency because the recuperation process can complete within 16.67 ms. Thirdly, different operating conditions correspond to particular optimal expansion ratio. Fourthly, increasing the pump pressure and maintaining appropriate superheated degree

  4. Balloon-Expandable Stent Graft for Treating Uretero-Iliac Artery Fistula

    Energy Technology Data Exchange (ETDEWEB)

    Guntau, Moritz, E-mail: guntau@med.uni-marburg.de [Philipps University, Department of Diagnostic and Interventional Radiology, Marburg University Hospital (Germany); Hegele, Axel [Philipps University, Department of Urology and Pediatric Urology, Marburg University Hospital (Germany); Rheinheimer, Stephan [Philipps University, Department of Diagnostic and Interventional Radiology, Marburg University Hospital (Germany); Hofmann, Rainer [Philipps University, Department of Urology and Pediatric Urology, Marburg University Hospital (Germany); Mahnken, Andreas H. [Philipps University, Department of Diagnostic and Interventional Radiology, Marburg University Hospital (Germany)

    2017-06-15

    PurposeTo evaluate the safety, efficacy and outcome of percutaneous balloon-expandable covered stent graft placement for uretero-iliac artery fistula (UAF) treatment.MethodsThis retrospective study evaluated the single-center experience of percutaneous balloon-expandable covered stent graft placement (ADVANTA™, Atrium Hudson, NH, USA) in UAF. Data were obtained from a prospective institutional database. Patient follow-up included complications, symptoms recurrence and mortality rate.ResultsTen UAFs in eight patients (3 males; 5 females) with a mean age of 64.5 (35–77) years were identified. All patients had a history pelvic malignancy, extirpative surgery (n = 6), long-term ureteral stenting (n = 7) and pelvic radiation (n = 5). All procedures were completed successfully without complications. Thirty-day mortality rate was zero. At a median follow-up of 6 (1–60) months, one patient suffered recurrent hematuria requiring a secondary stent graft placement 26 months after the initial treatment. During follow-up, five patients died of the underlying disease (43, 66, 105, and 183 and 274 days after the last procedure).ConclusionPercutaneous balloon-expandable stent graft placement in UAF is a safe and effective treatment option. Implantation of stent grafts should be considered as treatment of choice in UAF.

  5. Enhancing microbial production of biofuels by expanding microbial metabolic pathways.

    Science.gov (United States)

    Yu, Ping; Chen, Xingge; Li, Peng

    2017-09-01

    Fatty acid, isoprenoid, and alcohol pathways have been successfully engineered to produce biofuels. By introducing three genes, atfA, adhE, and pdc, into Escherichia coli to expand fatty acid pathway, up to 1.28 g/L of fatty acid ethyl esters can be achieved. The isoprenoid pathway can be expanded to produce bisabolene with a high titer of 900 mg/L in Saccharomyces cerevisiae. Short- and long-chain alcohols can also be effectively biosynthesized by extending the carbon chain of ketoacids with an engineered "+1" alcohol pathway. Thus, it can be concluded that expanding microbial metabolic pathways has enormous potential for enhancing microbial production of biofuels for future industrial applications. However, some major challenges for microbial production of biofuels should be overcome to compete with traditional fossil fuels: lowering production costs, reducing the time required to construct genetic elements and to increase their predictability and reliability, and creating reusable parts with useful and predictable behavior. To address these challenges, several aspects should be further considered in future: mining and transformation of genetic elements related to metabolic pathways, assembling biofuel elements and coordinating their functions, enhancing the tolerance of host cells to biofuels, and creating modular subpathways that can be easily interconnected. © 2016 International Union of Biochemistry and Molecular Biology, Inc.

  6. Ion acoustic waves and double-layers in electronegative expanding plasmas

    International Nuclear Information System (INIS)

    Plihon, Nicolas; Chabert, Pascal

    2011-01-01

    Ion acoustic waves and double-layers are observed in expanding plasmas in electronegative gases, i.e., plasmas containing an appreciable fraction of negative ions. The reported experiments are performed in argon gas with a variable amount of SF 6 . When varying the amount of SF 6 , the negative ion fraction increases and three main regimes were identified previously: (i) the plasma smoothly expands at low negative ion fraction, (ii) a static double-layer (associated with an abrupt potential drop and ion acceleration) forms at intermediate negative ion fraction, (iii) double-layers periodically form and propagate (in the plasma expansion direction) at high negative ion fraction. In this paper, we show that transition phases exist in between these regimes, where fluctuations are observed. These fluctuations are unstable slow ion acoustic waves, propagating in the direction opposite to the plasma expansion. These fluctuations are excited by the most unstable eigenmodes and display turbulent features. It is suggested that the static double layer forms when the ion acoustic fluctuations become non-linearly unstable: the double layer regime being a bifurcated state of the smoothly expanding regime. For the highest negative ion fraction, a coexistence of (upstream propagating) slow ion acoustic fluctuations and (downstream) propagating double layers was observed.

  7. Enhancing results : solid expandable tubulars facilitate high-temperature oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Noel, G.; Nylund, J.; Flaming, S. [Enventure Global Technology LLC, Calgary, AB (Canada)

    2010-07-01

    Steam-based recovery methods can provide a cost-effective approach to developing heavy oil and oil sands energy resources. This paper described a solid expandable tubular system designed to prevent damage without decreases in hole size. The pipe's permanent deformation creates an energized seal that cases off damaged tubulars. The new sealing systems allow for operations in the range of 270 degrees C. The system was comprised of mechanical retainers designed to hold the multi-component, high-temperature seal in place on the expandable casing. The seals are held in place by retainer rings designed to protect the seal in the hole as well as to provide increased anchoring capacity when the pipe is expanded and clad onto the base casing. The retainers are wrapped with a redundant standard seal material. The weight and size of the casings are individually configured for specific wells and are also designed to maintain consistency across multiple weight ranges. Details of the testing protocol used to ensure that the sealing system operated well in various oil production scenarios were presented, as well as the results of case studies conducted to demonstrate the system in the field. 6 refs., 1 tab., 2 figs.

  8. Polypropylenes foam consisting of thermally expandable microcapsule as blowing agent

    Science.gov (United States)

    Jeoung, Sun Kyung; Hwang, Ye Jin; Lee, Hyun Wook; Kwak, Sung Bok; Han, In-Soo; Ha, Jin Uk

    2016-03-01

    The structure of thermally expandable microcapsule (TEMs) is consisted of a thermoplastic shell which is filled with liquid hydrocarbon at core. The shell of TEMs becomes soft when the temperature is higher than boiling temperature of liquid hydrocarbon. The shell of TEMs is expanded under the high temperature because the inner pressure of TEMs is increased by vaporization of hydrocarbon core. Therefore, the TEMs are applicable for blowing agents and light weight fillers. In this research, we fabricated the polypropylene (PP) foam by using the TEMs and chemical blowing agents and compared to their physical properties. The density of the specimen was decreased when the contents of chemical blowing agents and TEMs were increased. In addition, the mechanical properties (i.e. tensile strength and impact strength) of specimens were deteriorated with increasing amount of chemical blowing agents and TEMs. However, PP foam produced with TEMs showed higher impact strength than the one with the chemical blowing agent. In order to clarify the dependence of impact strength of PP foam as the blowing agent, the morphology difference of the PP foams was investigated. Expanding properties of PP foams produced with TEMs was changed with TEMs content of PP foams. Processing conditions also influenced the mechanical properties of PP foam containing TEMs.

  9. Expanding a digital content management system for the growing digital media enterprise

    CERN Document Server

    Arthur, Magan H

    2013-01-01

    Building large integrated content management systems is a daunting task and there is little guidance for the implementation process for the mid-level manager. There are thousands of home grown or old standalone systems in need of upgrading and expanding to keep up with the growing challenge of digital media. This book allows the non-technical executive to understand the key concepts and issues. It covers the technical process and business aspects of expanding a system.

  10. Surface-modified electrodes (SME)

    NARCIS (Netherlands)

    Schreurs, J.P.G.M.; Barendrecht, E.

    1984-01-01

    This review deals with the literature (covered up to August 1983), the characterization and the applications of Surface-Modified Electrodes (SME). As a special class of SME's, the Enzyme-Modified Electrode (EME) is introduced. Three types of modification procedures are distinguished; i.e. covalent

  11. Environmental Assessment Expanded Ponnequin Wind Energy Project Weld County, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    N/A

    1999-03-02

    The U.S.Department of Energy (DOE) has considered a proposal from the State of Colorado, Office of Energy Conservation (OEC), for funding construction of the Expanded Ponnequin Wind Project in Weld County, Colorado. OEC plans to enter into a contracting arrangement with Public Service Company of Colorado (PSCO) for the completion of these activities. PSCo, along with its subcontractors and business partners, are jointly developing the Expanded Ponnequin Wind Project. DOE completed an environmental assessment of the original proposed project in August 1997. Since then, the geographic scope and the design of the project changed, necessitating additional review of the project under the National Environmental Policy Act. The project now calls for the possible construction of up to 48 wind turbines on State and private lands. PSCo and its partners have initiated construction of the project on private land in Weld County, Colorado. A substation, access road and some wind turbines have been installed. However, to date, DOE has not provided any funding for these activities. DOE, through its Commercialization Ventures Program, has solicited applications for financial assistance from state energy offices, in a teaming arrangement with private-sector organizations, for projects that will accelerate the commercialization of emerging renewable energy technologies. The Commercialization Ventures Program was established by the Renewable Energy and Energy Efficiency Technology Competitiveness Act of 1989 (P.L. 101-218) as amended by the Energy Policy Act of 1992 (P.L. 102-486). The Program seeks to assist entry into the marketplace of newly emerging renewable energy technologies, or of innovative applications of existing technologies. In short, an emerging renewable energy technology is one which has already proven viable but which has had little or no operational experience. The Program is managed by the Department of Energy, Office of Energy Efficiency and Renewable Energy. The

  12. The treatment of complex airway diseases with inverted Y-shaped self-expandable metal stent

    International Nuclear Information System (INIS)

    Li Jianming; Jia Guangzhi

    2011-01-01

    Objective: To investigate the application and therapeutic effects of inverted Y-shaped self-expandable metal airway stent in treating complex airway diseases (stenosis or fistula). Methods: According to the distinctive anatomic structure and the pathological changes of complex airway stenosis or fistula, the inverted y-shaped self-expandable metal airway stent was designed. Under fluoroscopic monitoring, a total of 12 inverted Y-shaped self-expandable metal stents were implanted in 12 patients with complex airway diseases. Results: Stent placement in the trachea-bronchial tree was technically successful in all patients. After the operation, the symptom of dyspnea was immediately relieved and the bucking following food intake disappeared. The general physical condition and living quality were much improved in all patients. Conclusion: The use of inverted Y-shaped self-expandable metal airway stent for the management of complex airway stenosis involving the tracheal carina was a simple and safe procedure and it has satisfactory short-term clinical results. (authors)

  13. The technique study and primary clinical application of inverted Y-shaped self-expandable metal airway stent

    International Nuclear Information System (INIS)

    Han Xinwei; Wu Gang; Ma Ji; Yang Ruimin; Guan Sheng; Ma Nan; Wang Yanli

    2007-01-01

    Objective: To investigate the feasibility and primary therapeutic effect of inverted Y-shaped self-expandable metal stent for complex airway stenosis. Methods: On the standpoint of the peculiar anatomic structure and the pathological changes of complex airway stenosis, we designed the inverted Y-shaped self-expandable metal stent. Under the fluoroscopic guidance, 7 stents were implanted in 7 cases of airway complex stenosis. Results: The inverted Y-shaped self-expandable metal stents were placed seccussfully, with instantaneous relief of dyspnea and improvement of living quality. Conclusion: The placement of inverted Y-shaped self-expandable metal stent is feasible and safe for treating airway complex stenosis. (authors)

  14. Expanding hollow metal rings

    Science.gov (United States)

    Peacock, Harold B [Evans, GA; Imrich, Kenneth J [Grovetown, GA

    2009-03-17

    A sealing device that may expand more planar dimensions due to internal thermal expansion of a filler material. The sealing material is of a composition such that when desired environment temperatures and internal actuating pressures are reached, the sealing materials undergoes a permanent deformation. For metallic compounds, this permanent deformation occurs when the material enters the plastic deformation phase. Polymers, and other materials, may be using a sealing mechanism depending on the temperatures and corrosivity of the use. Internal pressures are generated by either rapid thermal expansion or material phase change and may include either liquid or solid to gas phase change, or in the gaseous state with significant pressure generation in accordance with the gas laws. Sealing material thickness and material composition may be used to selectively control geometric expansion of the seal such that expansion is limited to a specific facing and or geometric plane.

  15. Modified blank ammunition injuries.

    Science.gov (United States)

    Ogunc, Gokhan I; Ozer, M Tahir; Coskun, Kagan; Uzar, Ali Ihsan

    2009-12-15

    Blank firing weapons are designed only for discharging blank ammunition cartridges. Because they are cost-effective, are easily accessible and can be modified to live firearms plus their unclear legal situation in Turkish Law makes them very popular in Turkey. 2004 through 2008, a total of 1115 modified blank weapons were seized in Turkey. Blank firing weapons are easily modified by owners, making them suitable for discharging live firearm ammunition or modified blank ammunitions. Two common methods are used for modification of blank weapons. After the modification, these weapons can discharge the live ammunition. However, due to compositional durability problems with these types of weapons; the main trend is to use the modified blank ammunitions rather than live firearm ammunition fired from modified blank firing weapons. In this study, two types of modified blank weapons and two types of modified blank cartridges were tested on three different target models. Each of the models' shooting side was coated with 1.3+/-2 mm thickness chrome tanned cowhide as a skin simulant. The first model was only coated with skin simulant. The second model was coated with skin simulant and 100% cotton police shirt. The third model was coated with skin simulant and jean denim. After the literature evaluation four high risky anatomic locations (the neck area; the eyes; the thorax area and inguinal area) were pointed out for the steel and lead projectiles are discharged from the modified blank weapons especially in close range (0-50 cm). The target models were designed for these anatomic locations. For the target models six Transparent Ballistic Candle blocks (TCB) were prepared and divided into two test groups. The first group tests were performed with lead projectiles and second group with steel projectile. The shortest penetration depth (lead projectile: 4.358 cm; steel projectile 8.032 cm) was recorded in the skin simulant and jean denim coated block for both groups. In both groups

  16. Expanded porphyrins as third order non-linear optical materials ...

    Indian Academy of Sciences (India)

    WINTEC

    function correlations ... An understanding of the structure–function corre- lations of these expanded porphyrins is an important first step for ... where χ (2) and χ (3) are the quadratic χ (2) (first- order) and χ (3) cubic (second-order) susceptibilities.

  17. Summary of Investigations of the Use of Modified Turbine Inlet Conditions in a Binary Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Mines, Gregory Lee

    2000-09-01

    Investigators at the Idaho National Engineering and Environmental Laboratory (INEEL) are developing technologies that will enhance the feasibility of generating electrical power from a hydrothermal resource. One of the concepts investigated is the use of modified inlet conditions in geothermal binary power plant turbines to increase the power generation. An inlet condition of interest allows the expanding vapor to enter the two-phase region, a mode of operation typically avoided because of concern that condensate would form and damage the turbine, degrading performance. INEEL investigators postulated that initially a supersaturated vapor would be supported, and that no turbine damage would occur. This paper summarizes the investigation of these expansions that began with testing of their condensation behavior, and culminated with the incorporation of these expansions into the operation of several commercial binary plant turbines.

  18. Crowd Around: Expanding Your Donor Pool with Crowdfunding

    Science.gov (United States)

    Jarrell, Andrea

    2013-01-01

    At most institutions, annual fund-giving is down. Crowdfunding sites allow people with a great idea or worthy cause to bypass traditional funding methods and take their case directly to web-savvy investors and donors. This article describes how higher education institutions are expanding their donor pool through such crowdfunding sites as USEED,…

  19. CT examination of expanding processes in cerebellopontine angle

    International Nuclear Information System (INIS)

    Bauer, J.; Kvicala, V.; Faltynova, E.

    1988-01-01

    A contribution is evaluated of computerized tomography to the diagnosis of expanding processes localized in the pontocerebellar corner of posterior cranial fossa, particularly neurinomas of n. statoacousticus. In cases of expanding processes in this region, especially in minor expansions, CT examination must be performed in a specially selected way, always after the intravenous administration of a contrast agent. The diagnosis of small neurinomas of n. statoacousticus, localized mostly in intracanalicullar portion, in the external auditory duct proved to be particularly difficult. In these cases, computerized pneumomeatography proved to be of a particular value; CT examination of the internal auditory duct and its neighbourhood was performed after previous filling of this region with air which, in most cases, well differentiated expansions into adjacent structures. It is confirmed in agreement with reports in the literature, that in cases of serious clinical suspicion and negative or controversial finding by classical CT examination, computerized pneumomeatography is the method of choice in the diagnosis of small isodense neurinomas of nervus statoacousticus. (author). 10 refs

  20. Proposal for Certifying Expandable Planetary Surface Habitation Structures

    Science.gov (United States)

    Dorsey, John T.

    2011-01-01

    A factor-of-safety (FS) of 4.0 is currently used to design habitation structures made from structural soft goods. This approach is inconsistent with using a FS of 2.0 for metallic and polymeric composite pressure vessels as well as soft good structures such as space suits and parachutes. This inconsistency arises by using the FS to improperly account for the unknown effects of a variety of environmental and loading uncertainties. Using a 4.0 FS not only results in additional structural mass, it also makes it difficult to gain insight into the limitations of the material and/or product form and thus, it becomes difficult to make improvements. In order to bring consistency to the design and certification of expandable habitat structures, the approach used by the Federal Aviation Administration (FAA) to certify polymeric composite aircraft structures is used as a model and point of departure. A draft certification plan for Expandable Habitat Structures is developed in this paper and offered as an option for placing habitats made from soft goods on an equal footing with other structural implementations.

  1. Ecological and evolutionary processes at expanding range margins.

    Science.gov (United States)

    Thomas, C D; Bodsworth, E J; Wilson, R J; Simmons, A D; Davies, Z G; Musche, M; Conradt, L

    2001-05-31

    Many animals are regarded as relatively sedentary and specialized in marginal parts of their geographical distributions. They are expected to be slow at colonizing new habitats. Despite this, the cool margins of many species' distributions have expanded rapidly in association with recent climate warming. We examined four insect species that have expanded their geographical ranges in Britain over the past 20 years. Here we report that two butterfly species have increased the variety of habitat types that they can colonize, and that two bush cricket species show increased fractions of longer-winged (dispersive) individuals in recently founded populations. Both ecological and evolutionary processes are probably responsible for these changes. Increased habitat breadth and dispersal tendencies have resulted in about 3- to 15-fold increases in expansion rates, allowing these insects to cross habitat disjunctions that would have represented major or complete barriers to dispersal before the expansions started. The emergence of dispersive phenotypes will increase the speed at which species invade new environments, and probably underlies the responses of many species to both past and future climate change.

  2. Parental Intentions to Enroll Children in a Voluntary Expanded Newborn Screening Program

    Science.gov (United States)

    Paquin, Ryan S.; Peay, Holly L.; Gehtland, Lisa M.; Lewis, Megan A.; Bailey, Donald B.

    2016-01-01

    Background and Objectives Nearly all babies in the United States are tested at birth for rare, serious, and treatable disorders through mandatory state newborn screening (NBS). Recently, there have been calls for an expanded, voluntary model to facilitate early diagnosis and treatment of a wider range of disorders. We applied the reasoned action framework to examine parental intentions to participate in voluntary expanded screening. Methods We recruited a national cohort of recent and expectant parents living in the U.S. who completed a self-administered online survey (N = 1,001). Using a mixed-level fractional factorial experiment, we studied parental participation intentions and preferences for timing of consent, cost, consent format, and testing options. Results We conducted a hierarchical regression analysis assessing parental intentions to participate in voluntary expanded NBS. Attitudes, perceived normative influence, and perceived behavioral control explained substantial variance in intention, with perceived normative influence emerging as the strongest predictor. We found no evidence that the manipulated program features altered mean levels of intention, but timing of parental permission, cost, and permission format moderated the relative importance of reasoned action constructs on intention. Conclusion Program design features may impact the psychological mechanisms underlying parental decision making for voluntary expanded screening. These results have important implications for parent education, outreach, and informed parental permission procedures. PMID:27526258

  3. Parental intentions to enroll children in a voluntary expanded newborn screening program.

    Science.gov (United States)

    Paquin, Ryan S; Peay, Holly L; Gehtland, Lisa M; Lewis, Megan A; Bailey, Donald B

    2016-10-01

    Nearly all babies in the United States are tested at birth for rare, serious, and treatable disorders through mandatory state newborn screening (NBS). Recently, there have been calls for an expanded, voluntary model to facilitate early diagnosis and treatment of a wider range of disorders. We applied the reasoned action framework to examine parental intentions to participate in voluntary expanded screening. We recruited a national cohort of recent and expectant parents living in the U.S. who completed a self-administered online survey (N = 1001). Using a mixed-level fractional factorial experiment, we studied parental participation intentions and preferences for timing of consent, cost, consent format, and testing options. We conducted a hierarchical regression analysis assessing parental intentions to participate in voluntary expanded NBS. Attitudes, perceived normative influence, and perceived behavioral control explained substantial variance in intention, with perceived normative influence emerging as the strongest predictor. We found no evidence that the manipulated program features altered mean levels of intention, but timing of parental permission, cost, and permission format moderated the relative importance of reasoned action constructs on intention. Program design features may impact the psychological mechanisms underlying parental decision making for voluntary expanded screening. These results have important implications for parent education, outreach, and informed parental permission procedures. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. The volume of fluid injected into the tissue expander and the tissue expansion

    Directory of Open Access Journals (Sweden)

    Mahmood Omranifard

    2014-01-01

    Full Text Available Background: Replacement of the lost tissue is the major concerns of the plastic surgeons. Expanded area should be coherent with the surrounding tissue. Tissue expansion technique is the reforming methods the skin tissue scarcities. Several methods for tissue expansion are available; including usage of silicon balloon and injecting fluid into the tissue expander. Materials and Methods: In a clinical trial study, 35 patients, with burn scars, in the face, skull and neck area were studied. We provided a tissue expander device with capacities of 125, 250 and 350cc. Fluid was injected inside the device, 3 consecutive weeks with 1-week interval. After 3 months the device was set out and the tissue expansion was measured using a transparent board and the results were analyzed. Multiple regression was done by SPSS 20 to analyze the data. Results: Regression model showed Skin expansion was positively correlated with the volume of the injected fluid. For each centimeter square of skin expansion, about 6-8 ml of fluid must be injected. Conclusion: Correction of skin defects resulting from burning scar is possible using tissue expanders. The tissue expansion is correlated with the amount of the injected fluid.

  5. Long-term outcome of self expandable metal stents for biliary obstruction in chronic pancreatitis.

    Science.gov (United States)

    Waldthaler, Alexander; Schütte, Kerstin; Weigt, Jochen; Kropf, Siegfried; Malfertheiner, Peter; Kahl, Stefan

    2013-01-10

    Insertion of a self-expandable metal stent is still controversial for treatment of benign common bile duct stenosis but can be a valuable alternative to surgical treatment. Aim of our study was to analyze the efficacy of covered and uncovered self-expandable metal stent in patients with chronic pancreatitis and common bile duct stenosis. Twenty patients with common bile duct stenosis due to alcoholic chronic pancreatitis were retrospective analyzed. All patients had advanced chronic pancreatitis, presenting with calcifications in pancreatic head. Uncovered self-expandable metal stent (uSEMS) were used in 11 patients (3 females, 8 males) while in 9 patients (3 females, 6 males) partially covered self-expandable metal stent (cSEMS) were inserted. All patients treated with self-expandable metal stent had contraindications for surgery. Overall mean follow up time was 155 weeks: 206 (52-412) weeks in uSEMS, and 93 (25-233) weeks in cSEMS, respectively. Stent patency was in mean 118 weeks: 159 (44-412) weeks in uSEMS and 67 (25-150) weeks in cSEMS (P=0.019). In the uSEMS group, reintervention was necessary in 5 patients (45%) due to stent obstruction, whereas in the cSEMS group 4 patients (44%) needed reintervention (2 obstructions, 2 migration). Stent migration is an early complication, compared to obstruction (P<0.05), and in cSEMS obstruction occurred significantly earlier compared to uSEMS (P<0.05). Patency of uSEMS was significantly longer compared to partially cSEMS. Available self-expandable metal stent, unfortunately, do not meet the demands on successful treatment of benign common bile duct stenosis.

  6. Safety of endoscopic removal of self-expandable stents after treatment of benign esophageal diseases.

    Science.gov (United States)

    van Halsema, Emo E; Wong Kee Song, Louis M; Baron, Todd H; Siersema, Peter D; Vleggaar, Frank P; Ginsberg, Gregory G; Shah, Pari M; Fleischer, David E; Ratuapli, Shiva K; Fockens, Paul; Dijkgraaf, Marcel G W; Rando, Giacomo; Repici, Alessandro; van Hooft, Jeanin E

    2013-01-01

    Temporary placement of self-expandable stents has been increasingly used for the management of benign esophageal diseases. To evaluate the safety of endoscopic removal of esophageal self-expandable stents placed for the treatment of benign esophageal diseases. Multicenter retrospective study. Six tertiary care centers in the United States and Europe. A total of 214 patients with benign esophageal diseases undergoing endoscopic stent removal. Endoscopic stent removal. Endoscopic techniques for stent removal, time to stent removal, and adverse events related to stent removal. A total of 214 patients underwent a total of 329 stent extractions. Stents were mainly placed for refractory strictures (49.2%) and fistulae (49.8%). Of the removed stents, 52% were fully covered self-expandable metal stents (FCSEMSs), 28.6% were partially covered self-expandable metal stents (PCSEMSs), and 19.5% were self-expandable plastic stents. A total of 35 (10.6%) procedure-related adverse events were reported, including 7 (2.1%) major adverse events. Multivariate analysis revealed that use of PCSEMSs (P stent removal. Favorable factors for successful stent removal were FCSEMSs (P ≤ .012) and stent migration (P = .010). No significant associations were found for stent indwelling time (P = .145) and stent embedding (P = .194). Retrospective analysis, only tertiary care centers. With an acceptable major adverse event rate of 2.1%, esophageal stent removal in the setting of benign disease was found to be a safe and feasible procedure. FCSEMSs were more successfully removed than self-expandable plastic stents and PCSEMSs. Adverse events caused by stent removal were not time dependent. Copyright © 2013 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  7. Carbohydrate plasma expanders for passive tumor targeting

    DEFF Research Database (Denmark)

    Hoffmann, Stefan; Caysa, Henrike; Kuntsche, Judith

    2013-01-01

    The objective of this study was to investigate the suitability of carbohydrate plasma volume expanders as a novel polymer platform for tumor targeting. Many synthetic polymers have already been synthesized for targeted tumor therapy, but potential advantages of these carbohydrates include inexpen...... was characterized in human colon carcinoma xenograft bearing nude mice. A tumor specific accumulation of HES 450 was observed, which proves it’s potential as carrier for passive tumor targeting....

  8. Validation of the Chinese Expanded Euthanasia Attitude Scale

    Science.gov (United States)

    Chong, Alice Ming-Lin; Fok, Shiu-Yeu

    2013-01-01

    This article reports the validation of the Chinese version of an expanded 31-item Euthanasia Attitude Scale. A 4-stage validation process included a pilot survey of 119 college students and a randomized household survey with 618 adults in Hong Kong. Confirmatory factor analysis confirmed a 4-factor structure of the scale, which can therefore be…

  9. Energy spectra of gold and silver ions jointly expanding in multielement laser plasma

    International Nuclear Information System (INIS)

    Bedilov, M.R.; Kuramatov, D.; Tsoj, T.G.; Kholbaev, A.; Khaitbaev, K.

    1986-01-01

    The results of the investigations on energy distribution of Au and Ag ions jointly expanding in multielement paser plasma are presented. It is denonstrated, that on the stages of formation and expanding of multielement plasma multucharged ions considerable contribution is made by collision processes between electrons and ions and between ions of light and heavy elements. The results are discussed on the basis of existing theoretical models

  10. Expanding the Conversation: Further Explorations into Indigenous Environmental Science Education Theory, Research, and Practice

    Science.gov (United States)

    Lowan, Greg

    2012-01-01

    Indigenous environmental science education is a diverse, dynamic, and rapidly expanding field of research, theory, and practice. This article highlights, challenges, and expands upon key areas of discussion presented by Mack et al. (Cult Stud Sci Educ 7, "2012") as part of the forum on their article "Effective Practices for Creating…

  11. Resistance evaluation expanded perlite the leaching acid: variation of parameters concentration, time and leaching agent

    International Nuclear Information System (INIS)

    Almeida, J.M.F. de; Damasceno Junior, E.; Oliveira, E.S.; Fernandes, N.S.

    2016-01-01

    The expanded perlite is an amorphous aluminosilicate which presents in its composition about 75.0% silicon oxide (SiO2), also having other species in the composition as oxides of some metals. Silicas and silicates have been used in the environmental field, in relevant anti-corrosive activity. In this context, materials that exposes too many highly acidic media, require preservation against this type of wear, as this type of damage causes a great financial loss, thereby requiring low-cost, abundant materials, non-toxic and easy to purchase as some silica coating. The study evaluated the perlite expanded resistance against an acid leaching process. With undeniability the use of strong acids and different working conditions were not able to remove the oxides present on the expanded perlite sample, thus demonstrating the high strength of the expanded perlite against acid attacks. (author)

  12. Multifragment disintegrations of expanding nuclear systems

    International Nuclear Information System (INIS)

    Gelbke, K.

    1993-01-01

    Two phase transitions are expected to exist in bulk nuclear matter: a liquid-gas phase transition and a deconfinement transition to a quark-gluon plasma. In studies of nucleus-nucleus collisions, conditions similar to those pertaining to phase transitions in infinite systems can be created, but the fundamental problem yet to be solved is the identification of remnant signatures uniquely related to either of these phase transitions. Nuclear systems at densities and temperatures corresponding to the liquid-gas coexistence region can be produced in intermediate energy nucleus-nucleus collisions; they are expected to decay into many intermediate mass fragments (IMF's: Z=3-20). Recent investigations with low-threshold electronic 4π detector arrays have firmly established the occurrence of multifragment disintegrations of hot nuclear systems and allowed to challenge various theoretical approaches. In this talk, an overview of pertinent experimental results on multifragmentation will be presented and discussed. it will be shown that current microscopic transport theories designed to treat the growth of density fluctuations predict fragment multiplicities much smaller than observed experimentally. Measurements of the time scales of fragment formation are consistent with statistical model calculations for expanding hot nuclear system which indicate that fragments may form during a rather narrow time interval after the system has cooled and expanded to a density below that of normal nuclear matter. The expansion rate (and hence the fragment multiplicity) is sensitive to the equation of state (EOS). However, a number of recent results provide increasing evidence that current theoretical treatments need to be refined to allow an experimental determination of the EOS

  13. Liver myeloid-derived suppressor cells expand in response to liver metastases in mice and inhibit the anti-tumor efficacy of anti-CEA CAR-T

    Science.gov (United States)

    Burga, Rachel A.; Thorn, Mitchell; Point, Gary R.; Guha, Prajna; Nguyen, Cang T.; Licata, Lauren A.; DeMatteo, Ronald P.; Ayala, Alfred; Espat, N. Joseph; Junghans, Richard P.; Katz, Steven C.

    2015-01-01

    Chimeric antigen receptor modified T cell (CAR-T) technology, a promising immunotherapeutic tool, has not been applied specifically to treat liver metastases (LM). While CAR-T delivery to LM can be optimized by regional intrahepatic infusion, we propose that liver CD11b+Gr-1+ myeloid-derived suppressor cells (L-MDSC) will inhibit the efficacy of CAR-T in the intrahepatic space. We studied anti-CEA CAR-T in a murine model of CEA+ LM and identified mechanisms through which L-MDSC expand and inhibit CAR-T function. We established CEA+ LM in mice and studied purified L-MDSC and responses to treatment with intrahepatic anti-CEA CAR-T infusions. L-MDSC expanded three-fold in response to LM and their expansion was dependent on GM-CSF, which was produced by tumor cells. L-MDSC utilized PD-L1 to suppress anti-tumor responses through engagement of PD-1 on CAR-T. GM-CSF, in cooperation with STAT3, promoted L-MDSC PD-L1 expression. CAR-T efficacy was rescued when mice received CAR-T in combination with MDSC depletion, GM-CSF neutralization to prevent MDSC expansion, or PD-L1 blockade. As L-MDSC suppressed anti-CEA CAR-T, infusion of anti-CEA CAR-T in tandem with agents targeting L-MDSC is a rational strategy for future clinical trials. PMID:25850344

  14. Fluorescent cellulose nanocrystals via supramolecular assembly of terpyridine-modified cellulose nanocrystals and terpyridine-modified perylene

    International Nuclear Information System (INIS)

    Hassan, Mohammad L.; Moorefield, Charles M.; Elbatal, Hany S.; Newkome, George R.; Modarelli, David A.; Romano, Natalie C.

    2012-01-01

    Highlights: ► Surfaces of cellulose nanocrystals were modified with terpyridine ligands. ► Fluorescent nanocrystals could be obtained via self-assembly of terpyridine-modified perylene dye onto the terpyridine-modified cellulose nanocrystals. ► Further self-assembly of azide-functionalized terpyridine onto the fluorescent cellulose nanocrystals was possible to obtain nanocellulosic material with expected use in bioimaging. - Abstract: Due to their natural origin, biocompatibility, and non-toxicity, cellulose nanocrystals are promising candidates for applications in nanomedicine. Highly fluorescent nanocellulosic material was prepared via surface modification of cellulose nanocrystals with 2,2′:6′,2″-terpyridine side chains followed by supramolecular assembly of terpyridine-modified perylene dye onto the terpyridine-modified cellulose nanocrystals (CTP) via Ru III /Ru II reduction. The prepared terpyridine-modified cellulose-Ru II -terpyridine-modified perylene (CTP-Ru II -PeryTP) fluorescent nanocrystals were characterized using cross-polarized/magic angle spin 13 C nuclear magnetic resonance (CP/MAS 13 C NMR), Fourier transform infrared (FTIR), UV–visible, and fluorescence spectroscopy. In addition, further self-assembly of terpyridine units with azide functional groups onto CTP-Ru II -PeryTP was possible via repeating the Ru III /Ru II reduction protocol to prepare supramolecular fluorescent nanocrystals with azide functionality (CTP-Ru II -PeryTP-Ru II -AZTP). The prepared derivative may have potential application in bio-imaging since the terminal azide groups can be easily reacted with antigens via “Click” chemistry reaction.

  15. Enhanced Stormwater Contaminant Removal and Improved Runoff Quality Using Modified Sorbents in Tree Filters

    Science.gov (United States)

    Schifman, L. A.; Kasaraneni, V.; Boving, T. B.; Oyanedel-Craver, V.

    2013-12-01

    Stormwater runoff, particularly in urban areas, contains high concentrations of pathogens that are often cited as one of the main reasons for beach closings and other water quality issues in coastal areas. Commonly found contaminants in runoff are often addressed by structural best management practices (BMP) that capture and treat the runoff before discharging it. Many BMP, such as tree filters, act as primary filtration devices that attenuate total suspended solids, nutrients, and heavy metals from runoff, but typically these BMPs are not designed to treat bacteria and have only minor petroleum hydrocarbon (PH) treatment capabilities. To address this shortcoming, the contaminant retention of an alternative sorption material was compared to expanded shale that is usually used in tree filters. Red cedar wood chips were modified with either Quaternary Ammonium Silane (QAS) or Silver Nanoparticles (AgNPs) to provide antimicrobial properties to the matrix and/or exploit their affinity to sorb PH, particularly polycyclic aromatic hydrocarbons (PAH). Results show that the wood chips exhibit the highest sorption capacity for QAS, making this material favorable for treating bacteria, while at the same time attenuating PAH by sorption processes. In the case of AgNP amendment to wood, less AgNP uptake and more desorption from the wood matrix was observed, making this amendment less favorable for bacteria deactivation. Batch experiments show that wood chips modified with QAS can remove up to 3 orders of magnitude of bacteria and retain up to 0.1 mg/g of PAH compared to shale, which has very limited bacteria deactivation (less than one order of magnitude) a PAH retention capacity of 0.04 mg/g. In this talk, the contaminant removal efficiency of the modified and unmodified materials will be discussed on the background of how these materials may find use in enhanced treatment of stormwater in tree filter BMPs.

  16. Investigation of hydrodynamic parameters in a novel expanded bed configuration: local axial dispersion characterization and an empirical correlation study

    Directory of Open Access Journals (Sweden)

    E. S. Taheri

    2012-12-01

    Full Text Available Study of liquid behavior in an expanded bed adsorption (EBA system is important for understanding, modeling and predicting nanobioproduct/biomolecule adsorption performance in such processes. In this work, in order to analyze the local axial dispersion parameters, simple custom NBG (Nano Biotechnology Group expanded bed columns with 10 and 26 mm inner diameter were modified by insertion of sampling holes. Based on this configuration, the particles and liquid can be withdrawn directly from various axial positions of the columns. Streamline DEAE particles were used as solid phase in this work. The effects of factors such as liquid velocity, viscosity, settled bed height and column diameter on the hydrodynamic parameters were investigated. Local bed voidages in different axial bed positions were measured by a direct procedure within the column with 26 mm diameter. Increasing trend of voidage with velocity at a certain position of the bed and with bed height at a certain degree of expansion was observed. Residence time distribution (RTD analysis at various bed points showed approximately uniform hydrodynamic behavior in the column with 10 mm diameter while a decreasing trend of mixing/dispersion along the bed height at a certain degree of expansion was seen in the column with 26 mm diameter. Also lower mixing/dispersion occured in the smaller diameter column. Finally, a combination of two empirical correlations proposed by Richardson-Zaki and Tong-Sun was successfully employed for identification of the bed voidage at various bed heights (RSSE=99.9%. Among the empirical correlations presented in the literatures for variation of the axial dispersion coefficient, the Yun correlation gave good agreement with our experimental data (RSSE=87% in this column.

  17. Splenic embolization in cirrhotic patients with portal hypertension

    International Nuclear Information System (INIS)

    Falappa, P.G.; Cotroneo, A.R.; De Cinque, M.; Maresca, G.; Patane', D.

    1988-01-01

    Over the last four years the authors performed transcatheter embolization of the splenic artery by Gianturco coils in 32 consecutive cirrhotic patients with portal hypertension, splenomegaly, cytopenia and gastro-esophageal varices endoscopically proved. This procedure was especially useful for treatement of splenomegaly and cytopenia because a constant reduction of spleen dimensions and increase in platelet count were registered. The effectiveness of transcatheter embolization and follow-up are based on clinic, hematologic and sonographic findings. Sonographic monitoring is believed to be very useful both to evaluate splenomegaly and signs of portal hypertension and to reveal splenic complications (abscesses). Severe complications have been never registered

  18. Short wavelength striations on expanding plasma clouds

    International Nuclear Information System (INIS)

    Winske, D.; Gary, S.P.

    1989-01-01

    The growth and evolution of short wavelength (< ion gyroradius) flute modes on a plasma expanding across an ambient magnetic field have been actively studied in recent years, both by means of experiments in the laboratory as well as in space and through numerical simulations. We review the relevant observations and simulations results, discuss the instability mechanism and related linear theory, and describe recent work to bring experiments and theory into better agreement. 30 refs., 6 figs

  19. Inextendibility of expanding cosmological models with symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Dafermos, Mihalis [University of Cambridge, Department of Pure Mathematics and Mathematical Statistics, Wilberforce Road, Cambridge CB3 0WB (United Kingdom); Rendall, Alan D [Max Planck Institute for Gravitational Physics, Albert Einstein Institute, Am Muehlenberg 1, D-14476 Golm (Germany)

    2005-12-07

    A new criterion for inextendibility of expanding cosmological models with symmetry is presented. It is applied to derive a number of new results and to simplify the proofs of existing ones. In particular, it shows that the solutions of the Einstein-Vlasov system with T{sup 2} symmetry, including the vacuum solutions, are inextendible in the future. The technique introduced adds a qualitatively new element to the available tool-kit for studying strong cosmic censorship. (letter to the editor)

  20. Feasibility of using bulk metallic glass for self-expandable stent applications.

    Science.gov (United States)

    Praveen Kumar, Gideon; Jafary-Zadeh, Mehdi; Tavakoli, Rouhollah; Cui, Fangsen

    2017-10-01

    Self-expandable stents are widely used to restore blood flow in a diseased artery segment by keeping the artery open after angioplasty. Despite the prevalent use of conventional crystalline metallic alloys, for example, nitinol, to construct self-expandable stents, new biomaterials such as bulk metallic glasses (BMGs) are being actively pursued to improve stent performance. Here, we conducted a series of analyses including finite element analysis and molecular dynamics simulations to investigate the feasibility of using a prototypical Zr-based BMG for self-expandable stent applications. We model stent crimping of several designs for different percutaneous applications. Our results indicate that BMG-based stents with diamond-shaped crowns suffer from severe localization of plastic deformation and abrupt failure during crimping. As a possible solution, we further illustrate that such abrupt failure could be avoided in BMG-based stents without diamond shape crowns. This work would open a new horizon for a quest toward exploiting superior mechanical and functional properties of metallic glasses to design future stents. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1874-1882, 2017. © 2016 Wiley Periodicals, Inc.

  1. Design of Radial Turbo-Expanders for Small Organic Rankine Cycle System

    Science.gov (United States)

    Arifin, M.; Pasek, A. D.

    2015-09-01

    This paper discusses the design of radial turbo-expanders for ORC systems. Firstly, the rotor blades were design and the geometry and the perfromance were calculated using several working fluid such as R134a, R143a, R245fa, n-Pentane, and R123. Then, a numerical study was carried out in the fluid flow area with R134a and R123 as the working fluid. Analyses were performed using Computational Fluid Dynamics (CFD) ANSYS CFX on two real gas models, with the k-epsilon and SST (shear stress transport) turbulence models. The results analysis shows the distribution of Mach number, pressure, velocity and temperature along the rotor blade of the radial turbo-expanders and estimation of performance at various operating conditions. CFD analysis show that if the flow area divided into 250,000 grid mesh, and using real gas model SST at steady state condition, 0.4 kg/s of mass flow rate, 15,000 rpm rotor speed, 5 bar inlet pressure, and 373K inlet temperature, the turbo expander produces 6.7 kW, and 5.5 kW of power when using R134a and R123 respectively.

  2. Modified Firefly Algorithm

    Directory of Open Access Journals (Sweden)

    Surafel Luleseged Tilahun

    2012-01-01

    Full Text Available Firefly algorithm is one of the new metaheuristic algorithms for optimization problems. The algorithm is inspired by the flashing behavior of fireflies. In the algorithm, randomly generated solutions will be considered as fireflies, and brightness is assigned depending on their performance on the objective function. One of the rules used to construct the algorithm is, a firefly will be attracted to a brighter firefly, and if there is no brighter firefly, it will move randomly. In this paper we modify this random movement of the brighter firefly by generating random directions in order to determine the best direction in which the brightness increases. If such a direction is not generated, it will remain in its current position. Furthermore the assignment of attractiveness is modified in such a way that the effect of the objective function is magnified. From the simulation result it is shown that the modified firefly algorithm performs better than the standard one in finding the best solution with smaller CPU time.

  3. Intermingled Bodies. Distributed Agency in an Expanded Appreciation of Making

    Directory of Open Access Journals (Sweden)

    Terence E. Rosenberg

    2013-09-01

    Full Text Available This article offers an expanded view of making and, concomitantly, an understanding that through making we constitute the way we are in the world. The article begins with the idea that making produces a 'surrogate' of the body, which extends the body into the world, reforming the body and the world and their relationship. The ideas the article offers run counter to certain currents of thought that reduce making to a narrow cast anthropocentric crafting. Instead of this reduction, where making is merely understood and fixated as a close inembodied handicraft, the article advances: first, that all that we produce is making – not just that which is crafted by the immediacy of a hand; and, second, and linked to this expanded view of making, that all making workst hrough a distributed agency that includes human and non-human actors and actants in meshworks that extend across space – synchronous - and across time –diachronous. In other words, the body is extended into the world through what is made and this made world acts ineluctably on, and in, making. The paper references the practices of three makers to make the case for the need, bothethical and poetic, to think about making as an expanded term and to consideran intentionality of making that works through distributed agency doubly constituted as material and narrative.

  4. In Vitro assessment of the nutritive value of expanded soybean meal for dairy cattle

    Directory of Open Access Journals (Sweden)

    Elwakeel Eman A

    2012-03-01

    Full Text Available Abstract Little information is available about the nutritive value of expanded soybean meal, which is produced by expansion of soybeans prior to solvent extraction of the oil. During processing, expanded soybean meal is subjected to additional heat, which might increase the concentration of ruminally undegraded protein. Processing of soybeans with heat during oil extraction could affect lysine availability by increasing ruminally undegraded protein or by impairing intestinal digestion. Our objective was to compare solvent and expanded soybeans with regard to chemical composition and nutritive value for dairy cattle. Samples of expanded soybean meal (n = 14 and solvent-extracted soybean meal (n = 5 were obtained from People's Republic of China to study effects of the expansion process on nutritive value for dairy cattle. Solvent-extracted soybean meal (n = 2 and mechanically extracted (heated soybean meal (n = 2 from the United States served as references for comparison. Samples were analyzed for crude fat, long-chain fatty acids, crude protein, amino acids, chemically available lysine, in situ ruminal protein degradation, and in vitro intestinal digestibility. No differences were found between solvent-extracted soybean meals from China and expanded soybean meals from China for crude fat, crude protein, amino acids, or chemically available lysine. In situ disappearance of nitrogen, ruminally undegraded protein content, and in vitro intestinal digestion of the ruminally undegraded protein were generally similar between solvent-extracted soybean meals made in China and expanded soybean meals made in China; variation among soybean meals was small. Results indicate that the additional heat from the expansion process was not great enough to affect the nutritive value of soybean meal protein for ruminants. Although expansion may improve the oil extraction process, the impact on the resulting soybean meal is minimal and does not require consideration

  5. Belowground Plant–Herbivore Interactions Vary among Climate-Driven Range-Expanding Plant Species with Different Degrees of Novel Chemistry

    Directory of Open Access Journals (Sweden)

    Rutger A. Wilschut

    2017-10-01

    Full Text Available An increasing number of studies report plant range expansions to higher latitudes and altitudes in response to global warming. However, consequences for interactions with other species in the novel ranges are poorly understood. Here, we examine how range-expanding plant species interact with root-feeding nematodes from the new range. Root-feeding nematodes are ubiquitous belowground herbivores that may impact the structure and composition of natural vegetation. Because of their ecological novelty, we hypothesized that range-expanding plant species will be less suitable hosts for root-feeding nematodes than native congeneric plant species. In greenhouse and lab trials we compared nematode preference and performance of two root-feeding nematode species between range-expanding plant species and their congeneric natives. In order to understand differences in nematode preferences, we compared root volatile profiles of all range-expanders and congeneric natives. Nematode preferences and performances differed substantially among the pairs of range-expanders and natives. The range-expander that had the most unique volatile profile compared to its related native was unattractive and a poor host for nematodes. Other range-expanding plant species that differed less in root chemistry from native congeners, also differed less in nematode attraction and performance. We conclude that the three climate-driven range-expanding plant species studied varied considerably in their chemical novelty compared to their congeneric natives, and therefore affected native root-feeding nematodes in species-specific ways. Our data suggest that through variation in chemical novelty, range-expanding plant species may vary in their impacts on belowground herbivores in the new range.

  6. TU-C-HORIZONS-01: The Expanding Horizons Travel Grant Program: ePosters and Discussion

    International Nuclear Information System (INIS)

    Siewerdsen, J; Jeraj, R

    2016-01-01

    The Expanding Horizons travel grant program provides opportunity for students and trainees to broaden the scope of scientific meetings they attend and gain insight from research outside traditional domains of medical physics. Through participation in such conferences, early-career researchers are introduced to new topics with relevance to medical physics research as a means to expand the scientific horizons of our discipline. This year, 21 Expanding Horizons travel grants were awarded, granting travel to 17 conferences, including: Radiomics, the World Molecular Imaging Society (WMIS), the 3D Printing Conference and Expo, the GPU Technology Conference, the SIAM Imaging Science Conference, the Human Brain Mapping Conference, the OSA Conference on Clinical and Translational Biophotonics, the Society for Neuroscience, the AACR Conference on Tumor Microenvironment, and the Conference on Knowledge Discovery and Data Mining. The Expanding Horizons electronic poster session gives a venue for AAPM conference attendees to meet and discuss with awardees, learn the hot topics and emerging research areas presented at these conferences, and understand the relevance to future medical physics research.

  7. TU-C-HORIZONS-01: The Expanding Horizons Travel Grant Program: ePosters and Discussion

    Energy Technology Data Exchange (ETDEWEB)

    Siewerdsen, J [Johns Hopkins University, Baltimore, MD (United States); Jeraj, R [University of Wisconsin, Madison, WI (United States)

    2016-06-15

    The Expanding Horizons travel grant program provides opportunity for students and trainees to broaden the scope of scientific meetings they attend and gain insight from research outside traditional domains of medical physics. Through participation in such conferences, early-career researchers are introduced to new topics with relevance to medical physics research as a means to expand the scientific horizons of our discipline. This year, 21 Expanding Horizons travel grants were awarded, granting travel to 17 conferences, including: Radiomics, the World Molecular Imaging Society (WMIS), the 3D Printing Conference and Expo, the GPU Technology Conference, the SIAM Imaging Science Conference, the Human Brain Mapping Conference, the OSA Conference on Clinical and Translational Biophotonics, the Society for Neuroscience, the AACR Conference on Tumor Microenvironment, and the Conference on Knowledge Discovery and Data Mining. The Expanding Horizons electronic poster session gives a venue for AAPM conference attendees to meet and discuss with awardees, learn the hot topics and emerging research areas presented at these conferences, and understand the relevance to future medical physics research.

  8. Chronic Expanding Hematoma in the Popliteal Fossa after Pseudoaneurysm Surgery because of Nail Puncture

    Directory of Open Access Journals (Sweden)

    Serdar Yilmaz

    2014-01-01

    Full Text Available Hematomas caused by surgery or trauma that persist and expand slowly for more than a month are defined as chronic expanding hematomas (CEH. Magnetic resonance imaging (MRI is useful for the diagnosis. Total excision with the pseudocapsule is the treatment method. Pseudoaneurysms result from arterial wall disruptions and can be mistaken for CEH. We present a rare case report of a 45-year-old man with a large, painful swelling in his left popliteal fossa. He had a puncture wound by a nail 11 years ago and a gradually expanding mass occurred in his popliteal fossa. A pseudoaneurysm was detected and operated a year later. After surgery, a gradually expanding mass recurred in his popliteal fossa. On the arteriography, the popliteal artery was occluded and the blood flow was maintained with collateral vessels. On MRI, an enormous swelling of 115 × 107 × 196 cm in diameter was seen. It was diagnosed as CEH and was excised completely protecting the collateral vessels and there was no recurrence after a year from the surgery.

  9. Preparation and characterization of stearic acid/expanded graphite composites as thermal energy storage materials

    International Nuclear Information System (INIS)

    Fang, Guiyin; Li, Hui; Chen, Zhi; Liu, Xu

    2010-01-01

    Stearic acid/expanded graphite composites with different mass ratios were prepared by absorbing liquid stearic acid into the expanded graphite. In the composite materials, the stearic acid was used as the phase change material for thermal energy storage, and the expanded graphite acted as the supporting material. Fourier transformation infrared spectroscopy, X-ray diffraction, scanning electron microscopy and thermal diffusivity measurement were used to determine the chemical structure, crystalline phase, microstructure and thermal diffusivity of the composites, respectively. The thermal properties and thermal stability were investigated by differential scanning calorimetry and thermogravimetric analysis. The thermal analysis results indicated that the materials exhibited the same phase transition characteristics as the stearic acid and their latent heats were approximately the same as the values calculated based on the weight fraction of the stearic acid in the composites. The microstructural analysis results showed that the stearic acid was well absorbed in the porous network of the expanded graphite, and there was no leakage of the stearic acid from the composites even when it was in the molten state.

  10. New expanded bed adsorbents for the recovery of DNA

    DEFF Research Database (Denmark)

    Theodossiou, Irini; Olander, M. A.; Sondergaard, M.

    2000-01-01

    A 20-40 mum pellicular high density (similar to3.7 g cm(-3)) expanded bed material has been designed for the capture of DNA and other large macromolecules. Anion exchangers fashioned out of these supports exhibited dramatically enhanced DNA binding capacities over commercial anion exchange...

  11. Experimental investigation of the ORC system in a cogenerative domestic power plant with a scroll expanders

    Science.gov (United States)

    Kaczmarczyk, Tomasz Z.; Ihnatowicz, Eugeniusz; Żywica, Grzegorz; Kiciński, Jan

    2015-11-01

    The paper presents the results of experimental investigations of the ORC system with two scroll expanders which have been used as a source of electricity. Theworking fluidwas HFE7100 - a newly engineered fluid with a unique heat transfer and favourable environmental properties. In the ORC system three heat exchangers were used (evaporator, regenerator, condenser) and before expanders the droplet separator was installed. As a source of heat an innovative biomass boiler was used. Studies have been carried out for the expanders worked in series and in parallel. The paper presents the thermal and fluidflow properties of the ORC installation for the selected flow rates and different temperatures of the working medium. The characteristics of output electrical power, operating speed and vibrations for scroll expanders were also presented.

  12. Chimeric antigen receptor-modified T cells for acute lymphoid leukemia.

    Science.gov (United States)

    Grupp, Stephan A; Kalos, Michael; Barrett, David; Aplenc, Richard; Porter, David L; Rheingold, Susan R; Teachey, David T; Chew, Anne; Hauck, Bernd; Wright, J Fraser; Milone, Michael C; Levine, Bruce L; June, Carl H

    2013-04-18

    Chimeric antigen receptor-modified T cells with specificity for CD19 have shown promise in the treatment of chronic lymphocytic leukemia (CLL). It remains to be established whether chimeric antigen receptor T cells have clinical activity in acute lymphoblastic leukemia (ALL). Two children with relapsed and refractory pre-B-cell ALL received infusions of T cells transduced with anti-CD19 antibody and a T-cell signaling molecule (CTL019 chimeric antigen receptor T cells), at a dose of 1.4×10(6) to 1.2×10(7) CTL019 cells per kilogram of body weight. In both patients, CTL019 T cells expanded to a level that was more than 1000 times as high as the initial engraftment level, and the cells were identified in bone marrow. In addition, the chimeric antigen receptor T cells were observed in the cerebrospinal fluid (CSF), where they persisted at high levels for at least 6 months. Eight grade 3 or 4 adverse events were noted. The cytokine-release syndrome and B-cell aplasia developed in both patients. In one child, the cytokine-release syndrome was severe; cytokine blockade with etanercept and tocilizumab was effective in reversing the syndrome and did not prevent expansion of chimeric antigen receptor T cells or reduce antileukemic efficacy. Complete remission was observed in both patients and is ongoing in one patient at 11 months after treatment. The other patient had a relapse, with blast cells that no longer expressed CD19, approximately 2 months after treatment. Chimeric antigen receptor-modified T cells are capable of killing even aggressive, treatment-refractory acute leukemia cells in vivo. The emergence of tumor cells that no longer express the target indicates a need to target other molecules in addition to CD19 in some patients with ALL.

  13. Pitfalls in soft tissue sarcoma imaging: chronic expanding hematomas.

    Science.gov (United States)

    Jahed, Kiarash; Khazai, Behnaz; Umpierrez, Monica; Subhawong, Ty K; Singer, Adam D

    2018-01-01

    Solid or nodular enhancement is typical of soft tissue sarcomas although high grade soft tissue sarcomas and those with internal hemorrhage often appear heterogeneous with areas of nonenhancement and solid or nodular enhancement. These MRI findings often prompt an orthopedic oncology referral, a biopsy or surgery. However, not all masses with these imaging findings are malignant. We report the multimodality imaging findings of two surgically proven chronic expanding hematomas (CEH) with imaging features that mimicked sarcomas. A third case of nonenhancing CEH of the lower extremity is also presented as a comparison. It is important that in the correct clinical scenario with typical imaging findings, the differential diagnosis of a chronic expanding hematoma be included in the workup of these patients. An image-guided biopsy of nodular tissue within such masses that proves to be negative for malignancy should not necessarily be considered discordant. A correct diagnosis may prevent a morbid unnecessary surgery and may indicate the need for a conservative noninvasive follow-up with imaging.

  14. Expandable Cryogenic Tankage for On Orbit Depot Storage, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed expandable depot storage tanks would make it possible to have an on-orbit tank larger in volume than any existing or planned launch vehicles. The size...

  15. Expanded newborn screening: social and ethical issues.

    Science.gov (United States)

    Dhondt, Jean-Louis

    2010-10-01

    Newborn screening and genetic testing have expanded rapidly in the last decade with the advent of multiplex (e.g., tandem mass spectrometry) and/or DNA technologies. However, screening panels include a large number of disorders, which may not meet all of the traditional screening criteria, established in late 1960s, and used for years to justify screening programs. After a period of expansion driven by technological advances, many reports have reconsidered the justification of expanded programs. Many factors have contributed to test-panel discrepancies between countries. The test-panel review methodology, the way health benefits are weighed against harms, and the socioeconomic-political environment all play a role. Expansion of screening also requires reconsideration of the infrastructure (ideally, in the context of national plans for rare diseases) to support testing, counselling, education, treatment, and follow-up. Consequently, economic aspects cannot be ignored and can be a limitation for expansion. New ethical questions have emerged: risks of discrimination or stigmatization, respect of the autonomy of persons to make decisions, parental anxiety resulting from a false positive test (especially when reporting to parents screening results for untreatable conditions identified as by-products of screening), etc. For disorders where there is not yet confirmation of benefit, it may be prudent to recommend pilot screening and to have a mechanism that can be used to adapt or even to stop a program.

  16. Expanded Endonasal Endoscopic Approach for Resection of an Infrasellar Craniopharyngioma.

    Science.gov (United States)

    Abou-Al-Shaar, Hussam; Blitz, Ari M; Rodriguez, Fausto J; Ishii, Masaru; Gallia, Gary L

    2016-11-01

    Craniopharyngiomas are uncommon benign locally aggressive epithelial tumors mostly located in the sellar and suprasellar regions. An infrasellar origin of these tumors is rare. The authors report a 22-year-old male patient with a purely infrasellar adamantinomatous craniopharyngioma centered in the nasopharynx with extension into the posterior nasal septum, sphenoid sinus, and clivus. Gross total resection was achieved using an expanded endonasal endoscopic transethmoidal, transsphenoidal, transpterygoid, and transclival approach. Follow-up at one year demonstrated no evidence of disease recurrence. Infrasellar craniopharyngioma should be included in the differential diagnosis of sinonasal masses even in the absence of sellar extension. Expanded endonasal endoscopic approaches provide excellent access to and visualization of such lesions and may obviate the need for postoperative radiotherapy when gross total resection is achieved. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Caudal Regression and Encephalocele: Rare Manifestations of Expanded Goldenhar Complex

    Directory of Open Access Journals (Sweden)

    Gabriella D’Angelo

    2017-01-01

    Full Text Available Oculoauriculovertebral spectrum, or Goldenhar Syndrome, is a condition characterized by variable degrees of uni- or bilateral involvement of craniofacial structures, ocular anomalies, and vertebral defects. Its expressivity is variable; therefore, the term “expanded Goldenhar complex” has been coined. The Goldenhar Syndrome usually involves anomalies in craniofacial structures, but it is known that nervous system anomalies, including encephalocele or caudal regression, may, rarely, occur in this condition. We report two rare cases of infants affected by Goldenhar Syndrome, associated with neural tube defects, specifically caudal regression syndrome and nasal encephaloceles, to underline the extremely complex and heterogeneous clinical features of this oculoauriculovertebral spectrum. These additional particular cases could increase the number of new variable spectrums to be included in the “expanded Goldenhar complex.”

  18. A Few Integrable Dynamical Systems, Recurrence Operators, Expanding Integrable Models and Hamiltonian Structures by the r -Matrix Method

    International Nuclear Information System (INIS)

    Zhang Yu-Feng; Muhammad, Iqbal; Yue Chao

    2017-01-01

    We extend two known dynamical systems obtained by Blaszak, et al. via choosing Casimir functions and utilizing Novikov–Lax equation so that a series of novel dynamical systems including generalized Burgers dynamical system, heat equation, and so on, are followed to be generated. Then we expand some differential operators presented in the paper to deduce two types of expanding dynamical models. By taking the generalized Burgers dynamical system as an example, we deform its expanding model to get a half-expanding system, whose recurrence operator is derived from Lax representation, and its Hamiltonian structure is also obtained by adopting a new way. Finally, we expand the generalized Burgers dynamical system to the (2+1)-dimensional case whose Hamiltonian structure is derived by Poisson tensor and gradient of the Casimir function. Besides, a kind of (2+1)-dimensional expanding dynamical model of the (2+1)-dimensional dynamical system is generated as well. (paper)

  19. The Impact of the Expanded Nursing Practice on Professional Identity in Denmark

    DEFF Research Database (Denmark)

    Piil, Karin; Kolbæk, Raymond; Ottmann, Goetz

    2012-01-01

    . The aim of this case study was to explore the impact of “nurse consultations,” representing an expanded nursing role, of 5 nurses focusing on their perception of autonomy, self-esteem, and confidence. Methods: The case study used semistructured interviews with 5 participants triangulated and validated...... gained a higher sense of autonomy, self-esteem, and confidence in their practice. These elements have a positive impact on their professional identity. Conclusion: The research demonstrates that for the nurses involved in expanded professional practice, the boundaries of professional practice have...

  20. Cobalt phthalocyanine modified electrodes utilised in electroanalysis: nano-structured modified electrodes vs. bulk modified screen-printed electrodes.

    Science.gov (United States)

    Foster, Christopher W; Pillay, Jeseelan; Metters, Jonathan P; Banks, Craig E

    2014-11-19

    Cobalt phthalocyanine (CoPC) compounds have been reported to provide electrocatalytic performances towards a substantial number of analytes. In these configurations, electrodes are typically constructed via drop casting the CoPC onto a supporting electrode substrate, while in other cases the CoPC complex is incorporated within the ink of a screen-printed sensor, providing a one-shot economical and disposable electrode configuration. In this paper we critically compare CoPC modified electrodes prepared by drop casting CoPC nanoparticles (nano-CoPC) onto a range of carbon based electrode substrates with that of CoPC bulk modified screen-printed electrodes in the sensing of the model analytes L-ascorbic acid, oxygen and hydrazine. It is found that no "electrocatalysis" is observed towards L-ascorbic acid using either of these CoPC modified electrode configurations and that the bare underlying carbon electrode is the origin of the obtained voltammetric signal, which gives rise to useful electroanalytical signatures, providing new insights into literature reports where "electrocatalysis" has been reported with no clear control experiments undertaken. On the other hand true electrocatalysis is observed towards hydrazine, where no such voltammetric features are witnessed on the bare underlying electrode substrate.

  1. Inborn errors of metabolism and expanded newborn screening: review and update.

    Science.gov (United States)

    Mak, Chloe Miu; Lee, Han-Chih Hencher; Chan, Albert Yan-Wo; Lam, Ching-Wan

    2013-11-01

    Inborn errors of metabolism (IEM) are a phenotypically and genetically heterogeneous group of disorders caused by a defect in a metabolic pathway, leading to malfunctioning metabolism and/or the accumulation of toxic intermediate metabolites. To date, more than 1000 different IEM have been identified. While individually rare, the cumulative incidence has been shown to be upwards of 1 in 800. Clinical presentations are protean, complicating diagnostic pathways. IEM are present in all ethnic groups and across every age. Some IEM are amenable to treatment, with promising outcomes. However, high clinical suspicion alone is not sufficient to reduce morbidities and mortalities. In the last decade, due to the advent of tandem mass spectrometry, expanded newborn screening (NBS) has become a mandatory public health strategy in most developed and developing countries. The technology allows inexpensive simultaneous detection of more than 30 different metabolic disorders in one single blood spot specimen at a cost of about USD 10 per baby, with commendable analytical accuracy and precision. The sensitivity and specificity of this method can be up to 99% and 99.995%, respectively, for most amino acid disorders, organic acidemias, and fatty acid oxidation defects. Cost-effectiveness studies have confirmed that the savings achieved through the use of expanded NBS programs are significantly greater than the costs of implementation. The adverse effects of false positive results are negligible in view of the economic health benefits generated by expanded NBS and these could be minimized through increased education, better communication, and improved technologies. Local screening agencies should be given the autonomy to develop their screening programs in order to keep pace with international advancements. The development of biochemical genetics is closely linked with expanded NBS. With ongoing advancements in nanotechnology and molecular genomics, the field of biochemical genetics

  2. Virginia Bioinformatics Institute to expand cyberinfrastructure education and outreach project

    OpenAIRE

    Whyte, Barry James

    2008-01-01

    The National Science Foundation has awarded the Virginia Bioinformatics Institute at Virginia Tech $918,000 to expand its education and outreach program in Cyberinfrastructure - Training, Education, Advancement and Mentoring, commonly known as the CI-TEAM.

  3. Evolution of gravitational orbits in the expanding universe

    International Nuclear Information System (INIS)

    Sereno, Mauro; Jetzer, Philippe

    2007-01-01

    The gravitational action of the smooth energy-matter components filling in the universe can affect the orbit of a planetary system. Changes are related to the acceleration of the cosmological scale size R. In a universe with significant dark matter, a gravitational system expands or contracts according to the amount and equation of state of the dark energy. At present time, the Solar System, according to the ΛCDM scenario emerging from observational cosmology, should be expanding if we consider only the effect of the cosmological background. Its fate is determined by the equation of state of the dark energy alone. The mean motion and periastron precession of a planet are directly sensitive to Re/R, whereas variations with time in the semimajor axis and eccentricity are related to its time variation. Actual bounds on the cosmological deceleration parameters q 0 from accurate astrometric data of perihelion precession and changes in the third Kepler's law in the Solar System fall short of 10 orders of magnitude with respect to estimates from observational cosmology. Future radio-ranging measurements of outer planets could improve actual bounds by 5 orders of magnitude

  4. Terrestrial Sagnac delay constraining modified gravity models

    Science.gov (United States)

    Karimov, R. Kh.; Izmailov, R. N.; Potapov, A. A.; Nandi, K. K.

    2018-04-01

    Modified gravity theories include f(R)-gravity models that are usually constrained by the cosmological evolutionary scenario. However, it has been recently shown that they can also be constrained by the signatures of accretion disk around constant Ricci curvature Kerr-f(R0) stellar sized black holes. Our aim here is to use another experimental fact, viz., the terrestrial Sagnac delay to constrain the parameters of specific f(R)-gravity prescriptions. We shall assume that a Kerr-f(R0) solution asymptotically describes Earth's weak gravity near its surface. In this spacetime, we shall study oppositely directed light beams from source/observer moving on non-geodesic and geodesic circular trajectories and calculate the time gap, when the beams re-unite. We obtain the exact time gap called Sagnac delay in both cases and expand it to show how the flat space value is corrected by the Ricci curvature, the mass and the spin of the gravitating source. Under the assumption that the magnitude of corrections are of the order of residual uncertainties in the delay measurement, we derive the allowed intervals for Ricci curvature. We conclude that the terrestrial Sagnac delay can be used to constrain the parameters of specific f(R) prescriptions. Despite using the weak field gravity near Earth's surface, it turns out that the model parameter ranges still remain the same as those obtained from the strong field accretion disk phenomenon.

  5. Experimental study on the performance of single screw expanders by gap adjustment

    International Nuclear Information System (INIS)

    Wang, Wei; Wu, Yu-ting; Ma, Chong-fang; Xia, Guo-dong; Wang, Jing-fu

    2013-01-01

    Improving thermodynamic efficiency of prime movers is the key issue for efficient utilization of low-temperature heat resources. Single screw expander may be a good candidate because of its many good characteristics. Precisions in manufacture and assembly are very important factors to the performance of single screw expanders. In this paper, the shaft efficiency, volumetric efficiency and gas consumption rate of the single screw expander prototypes were tested and discussed. We have manufactured three prototypes with different gaps to investigate their performance. The first prototype (A) has the largest gap, and the second one (B) has the smallest gap, the third prototype (C) has the medium gap configuration. Experimental result of the prototypes was obtained. From the experimental data of prototype A, the power output was about 5 kW, the gas consumption rate was above 105 kg/kWh and the volumetric efficiency was below 20%, the shaft efficiency was only 34%. From experimental data of prototype B, the mass flow rate was significantly decreased. The power output was only 1.4 kW and the volumetric efficiency was slightly lower than prototype A. The gas consumption rate was much more than that of prototype A. From the experimental data of prototype C, the power output was about 4.5 kW, but the mass flow rate was sharply decreased. The gas consumption rate was about 65 kg/kWh, the maximum volumetric efficiency was about 66%, and the shaft efficiency was about 60%. The experimental results indicated that prototype C of single screw expanders had the best overall performance, which may be further improved by optimizing its configuration. - Highlights: • The experiment for three single screw expander prototypes at different gaps was carried out. • Maximum shaft efficiency is about 60%. • Minimum gas consumption rate is about 65 kg/kWh. • Maximum volumetric efficiency is about 66%. • Leaked gas still has part of working capability

  6. Fire Resistance of Concrete Constructions with Expanded Clay Aggregate

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl

    2003-01-01

    The paper describes briefly a series of full-scale tests made as documentation for extending the field of application of the reduced cross section method from the structural codes to constructions based on expanded clay aggregate. As a special result the tests verify that slabs with a short ancho...

  7. Automated DNA extraction from genetically modified maize using aminosilane-modified bacterial magnetic particles.

    Science.gov (United States)

    Ota, Hiroyuki; Lim, Tae-Kyu; Tanaka, Tsuyoshi; Yoshino, Tomoko; Harada, Manabu; Matsunaga, Tadashi

    2006-09-18

    A novel, automated system, PNE-1080, equipped with eight automated pestle units and a spectrophotometer was developed for genomic DNA extraction from maize using aminosilane-modified bacterial magnetic particles (BMPs). The use of aminosilane-modified BMPs allowed highly accurate DNA recovery. The (A(260)-A(320)):(A(280)-A(320)) ratio of the extracted DNA was 1.9+/-0.1. The DNA quality was sufficiently pure for PCR analysis. The PNE-1080 offered rapid assay completion (30 min) with high accuracy. Furthermore, the results of real-time PCR confirmed that our proposed method permitted the accurate determination of genetically modified DNA composition and correlated well with results obtained by conventional cetyltrimethylammonium bromide (CTAB)-based methods.

  8. Expanded algal cultivation can reverse key planetary boundary transgressions

    Directory of Open Access Journals (Sweden)

    Dean Calahan

    2018-02-01

    Full Text Available Humanity is degrading multiple ecosystem services, potentially irreversibly. Two of the most important human impacts are excess agricultural nutrient loading in our fresh and estuarine waters and excess carbon dioxide in our oceans and atmosphere. Large-scale global intervention is required to slow, halt, and eventually reverse these stresses. Cultivating attached polyculture algae within controlled open-field photobioreactors is a practical technique for exploiting the ubiquity and high primary productivity of algae to capture and recycle the pollutants driving humanity into unsafe regimes of biogeochemical cycling, ocean acidification, and global warming. Expanded globally and appropriately distributed, algal cultivation is capable of removing excess nutrients from global environments, while additionally sequestering appreciable excess carbon. While obviously a major capital and operational investment, such a project is comparable in magnitude to the construction and maintenance of the global road transportation network. Beyond direct amelioration of critical threats, expanded algal cultivation would produce a major new commodity flow of biomass, potentially useful either as a valuable organic commodity itself, or used to reduce the scale of the problem by improving soils, slowing or reversing the loss of arable land. A 100 year project to expand algal cultivation to completely recycle excess global agricultural N and P would, when fully operational, require gross global expenses no greater than $2.3 × 1012 yr−1, (3.0% of the 2016 global domestic product and less than 1.9 × 107 ha (4.7 × 107 ac, 0.38% of the land area used globally to grow food. The biomass generated embodies renewable energy equivalent to 2.8% of global primary energy production.

  9. Self-expandable nitinol stent placement in homocysteinemic porcine aorta

    Directory of Open Access Journals (Sweden)

    Luís Henrique Gil França

    2008-01-01

    Full Text Available PURPOSE: To compare aortic intimal thickening of normal and hyperhomocysteinemic pigs (induced with a methionine-rich diet following placement of a self-expanding nitinol stent. METHODS: Eighteen Macau pigs were used. They were older than eight weeks in age and had an average weight of 30 kg. Pigs were randomly divided into two groups. The first, Group C (control, was fed a regular diet, and the second group, Group M, was fed a methionine-rich diet for 30 days to induce hyperhomocysteinemia. The self-expandable nitinol stents were 25mm in length and 8 mm in diameter after expansion. Blood samples were collected to measure total cholesterol, triglycerides, HDL and homocysteine concentrations. All animals were subjected to angiography. Thirty days after the procedure, the animals were sacrificed, and the abdominal aorta was removed for histological and digital morphometry analysis. RESULTS: Under microscopic evaluation, the intima was significantly thicker in Group C than in Group M. When groups were compared by digital morphometric analysis, intimal thickening of the vessel wall was higher in Group C than in Group M. There was no significant change in total cholesterol, triglycerides or HDL concentrations in either group. In group C the levels of plasma homocysteine ranged from 14,40 to 16,73µmol/l; in Group M, plasma homocysteine levels ranged from 17.47 to 59.80 µmol/l after 30 days of a methionine-rich diet. CONCLUSION: Compared to normal pigs, less intimal hyperplasia was observed in the abdominal aortas of hyperhomocysteinemic pigs thirty days after the insertion of a self-expandable nitinol stent.

  10. Particle creation and particle number in an expanding universe

    International Nuclear Information System (INIS)

    Parker, Leonard

    2012-01-01

    I describe the logical basis of the method that I developed in 1962 and 1963 to define a quantum operator corresponding to the observable particle number of a quantized free scalar field in a spatially-flat isotropically expanding (and/or contracting) universe. This work also showed for the first time that particles were created from the vacuum by the curved spacetime of an expanding spatially-flat Friedmann–Lemaître–Robertson–Walker (FLRW) universe. The same process is responsible for creating the nearly scale-invariant spectrum of quantized perturbations of the inflaton scalar field during the inflationary stage of the expansion of the universe. I explain how the method that I used to obtain the observable particle number operator involved adiabatic invariance of the particle number (hence, the name adiabatic regularization) and the quantum theory of measurement of particle number in an expanding universe. I also show how I was led in a surprising way, to the discovery in 1964 that there would be no particle creation by these spatially-flat FLRW universes for free fields of any integer or half-integer spin satisfying field equations that are invariant under conformal transformations of the metric. The methods I used to define adiabatic regularization for particle number were based on generally-covariant concepts like adiabatic invariance and measurement that were fundamental and determined results that were unique to each given adiabatic order. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical in honour of Stuart Dowker's 75th birthday devoted to ‘Applications of zeta functions and other spectral functions in mathematics and physics’. (paper)

  11. Clinical Outcomes of Self-Expandable Metal Stents for Malignant Rectal Obstruction.

    Science.gov (United States)

    Lee, Hyun Jung; Hong, Sung Pil; Cheon, Jae Hee; Kim, Tae Il; Kim, Won Ho; Park, Soo Jung

    2018-01-01

    Self-expandable metal stents are widely used to treat malignant colorectal obstruction. However, data on clinical outcomes of stent placement for rectal obstruction specifically are lacking. We aimed to investigate the clinical outcomes of self-expandable metal stents in malignant rectal obstruction in comparison with those in left colonic obstruction and to identify factors associated with clinical failure and complication. This was a retrospective study. The study was conducted at a tertiary care center. Between January 2005 and December 2013, medical charts of patients who underwent stent placement for malignant rectal or left colonic obstruction were reviewed retrospectively. Study intervention included self-expandable metal stent placement. Technical success, clinical success, and complications were measured. Technical success rates for the 2 study groups (rectum vs left colon, 93.5% vs 93.1%; p = 0.86) did not differ significantly; however, the clinical success rate was lower in patients with rectal obstruction (85.4% vs 92.1%; p = 0.02). In addition, the complication rate was higher in patients with rectal obstruction (37.4% vs 25.1%; p = 0.01). Patients with rectal obstruction showed higher rates of obstruction because of extracolonic malignancy (33.8% vs 15.8%; p stent use for palliation (78.6% vs 56.3%; p stent usage to be independent risk factors for clinical failure. Factors predictive of complications in the palliative group were total obstruction, obstruction because of extracolonic malignancy, and covered stent usage. This was a retrospective, single-center study. The efficacy and safety of stent placement for malignant rectal obstruction were comparable with those for left colonic obstruction. However, obstruction attributed to extracolonic malignancy, use of covered stents, and total obstruction negatively impacted clinical outcomes of self-expandable metal stent placement and must be considered by endoscopists. See Video Abstract at http

  12. Expanding of FOV of NaI(Tl) gamma camera detectors-Is it possible?

    International Nuclear Information System (INIS)

    Gayshan, Vadim L.; Gektin, A.V.; Boyarintsev, A.; Pedash, V.

    2006-01-01

    Every gamma camera detector used for medical imaging of conventional design faces the problem of distorted or no information readout at the areas closer to the edge of detectors. Obtaining position and energy information becomes almost impossible at distance 0-12 of PMT size from the edge. Therefore, in some designs were proposed losing of edge energy resolution while improving in spatial uniformity when it comes to imaging at the edges. This work is dedicated to understanding of the problem, mathematical simulations, practical tests and recommendations to build detectors with larger usable FOV without increasing in dimensions. To study the problem we built the test jig with linear motion source and readout electronics to simulate gamma cameras of PMTs. Based on simulation results the idea of modifying of crystal shape combined with specific light redirection system of baffles was tested and allowed to expand usable FOV. The results are presented and showed that for traditional NaI(Tl) scintillators using 2'' PMT may be possible to obtain relatively good spatial resolution starting from 4-5mm from the edge of a detector. The question of economical efficiency of proposed method is being investigated and a special detector manufacturing technology must be developed to accommodate this. While we believe that achieved results are very important for small size detectors (<20cm) they could be beneficial even for larger detectors used in whole body imaging systems

  13. Expanding the Boundaries of Behavioral Integrity in Organizations

    Science.gov (United States)

    2010-07-01

    happened to someone else, subordinates can rationally seek behavioral solutions that punish the managers or the organization they represent (i.e...Thousand Oaks, CA: Sage. Brief, A. P., & Motowidlo, S. J. 1986. Prosocial organizational behaviors . Academy of Management Review, 11(4): 710-725...Dissertation Publication 3. DATES COVERED (From - To) 15-03-2009 to 25-07-2010 4. TITLE AND SUBTITLE Expanding the Boundaries of Behavioral

  14. Scaling up: Expanding the impact of food security and nutrition ...

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

    2016-10-06

    Oct 6, 2016 ... IDRC invests in applied research projects to develop and test ... These solutions are products, technologies, methods, and practices with the ... The social business is expanding from the 55 franchises currently serving 25,000 ...

  15. Ambipolar ion acceleration in an expanding magnetic nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Longmier, Benjamin W; Carter, Mark D; Cassady, Leonard D; Chancery, William J; Diaz, Franklin R Chang; Glover, Tim W; Ilin, Andrew V; McCaskill, Greg E; Olsen, Chris S; Squire, Jared P [Ad Astra Rocket Company, 141 W. Bay Area Blvd, Webster, TX (United States); Bering, Edgar A III [Department of Physics and Department of Electrical and Computer Engineering, University of Houston, 617 Science and Research Building 1, Houston, TX (United States); Hershkowitz, Noah [Department of Engineering Physics, University of Wisconsin, 1500 Engineering Dr., Madison, WI (United States)

    2011-02-15

    The helicon plasma stage in the Variable Specific Impulse Magnetoplasma Rocket (VASIMR (registered)) VX-200i device was used to characterize an axial plasma potential profile within an expanding magnetic nozzle region of the laboratory based device. The ion acceleration mechanism is identified as an ambipolar electric field produced by an electron pressure gradient, resulting in a local axial ion speed of Mach 4 downstream of the magnetic nozzle. A 20 eV argon ion kinetic energy was measured in the helicon source, which had a peak magnetic field strength of 0.17 T. The helicon plasma source was operated with 25 mg s{sup -1} argon propellant and 30 kW of RF power. The maximum measured values of plasma density and electron temperature within the exhaust plume were 1 x 10{sup 20} m{sup -3} and 9 eV, respectively. The measured plasma density is nearly an order of magnitude larger than previously reported steady-state helicon plasma sources. The exhaust plume also exhibits a 95% to 100% ionization fraction. The size scale and spatial location of the plasma potential structure in the expanding magnetic nozzle region appear to follow the size scale and spatial location of the expanding magnetic field. The thickness of the potential structure was found to be 10{sup 4} to 10{sup 5} {lambda}{sub De} depending on the local electron temperature in the magnetic nozzle, many orders of magnitude larger than typical laboratory double layer structures. The background plasma density and neutral argon pressure were 10{sup 15} m{sup -3} and 2 x 10{sup -5} Torr, respectively, in a 150 m{sup 3} vacuum chamber during operation of the helicon plasma source. The agreement between the measured plasma potential and plasma potential that was calculated from an ambipolar ion acceleration analysis over the bulk of the axial distance where the potential drop was located is a strong confirmation of the ambipolar acceleration process.

  16. Biomechanical Analysis of an Expandable Lumbar Interbody Spacer.

    Science.gov (United States)

    Soriano-Baron, Hector; Newcomb, Anna G U S; Malhotra, Devika; Palma, Atilio E; Martinez-Del-Campo, Eduardo; Crawford, Neil R; Theodore, Nicholas; Kelly, Brian P; Kaibara, Taro

    2018-06-01

    Recently developed expandable interbody spacers are widely accepted in spinal surgery; however, the resulting biomechanical effects of their use have not yet been fully studied. We analyzed the biomechanical effects of an expandable polyetheretherketone interbody spacer inserted through a bilateral posterior approach with and without different modalities of posterior augmentation. Biomechanical nondestructive flexibility testing was performed in 7 human cadaveric lumbar (L2-L5) specimens followed by axial compressive loading. Each specimen was tested under 6 conditions: 1) intact, 2) bilateral L3-L4 cortical screw/rod (CSR) alone, 3) WaveD alone, 4) WaveD + CSR, 5) WaveD + bilateral L3-L4 pedicle screw/rod (PSR), and 6) WaveD + CSR/PSR, where CSR/PSR was a hybrid construct comprising bilateral cortical-level L3 and pedicle-level L4 screws interconnected by rods. The range of motion (ROM) with the interbody spacer alone decreased significantly compared with the intact condition during flexion-extension (P = 0.02) but not during lateral bending or axial rotation (P ≥ 0.19). The addition of CSR or PSR to the interbody spacer alone condition significantly decreased the ROM compared with the interbody spacer alone (P ≤ 0.002); and WaveD + CSR, WaveD + PSR, and WaveD + CSR/PSR (hybrid) (P ≥ 0.29) did not differ. The axial compressive stiffness (resistance to change in foraminal height during compressive loading) with the interbody spacer alone did not differ from the intact condition (P = 0.96), whereas WaveD + posterior instrumentation significantly increased compressive stiffness compared with the intact condition and the interbody spacer alone (P ≤ 0.001). The WaveD alone significantly reduced ROM during flexion-extension while maintaining the axial compressive stiffness. CSR, PSR, and CSR/PSR hybrid constructs were all effective in augmenting the expandable interbody spacer system and improving its stability. Copyright © 2018 Elsevier Inc. All

  17. `Un-Darkening' the Cosmos: New laws of physics for an expanding universe

    Science.gov (United States)

    George, William

    2017-11-01

    Dark matter is believed to exist because Newton's Laws are inconsistent with the visible matter in galaxies. Dark energy is necessary to explain the universe expansion. (also available from www.turbulence-online.com) suggested that the equations themselves might be in error because they implicitly assume that time is measured in linear increments. This presentation couples the possible non-linearity of time with an expanding universe. Maxwell's equations for an expanding universe with constant speed of light are shown to be invariant only if time itself is non-linear. Both linear and exponential expansion rates are considered. A linearly expanding universe corresponds to logarithmic time, while exponential expansion corresponds to exponentially varying time. Revised Newton's laws using either leads to different definitions of mass and kinetic energy, both of which appear time-dependent if expressed in linear time. And provide the possibility of explaining the astronomical observations without either dark matter or dark energy. We would have never noticed the differences on earth, since the leading term in both expansions is linear in δ /to where to is the current age.

  18. Expanding the Oral Hygiene Curriculum in a Nursing Program.

    Science.gov (United States)

    Briggs, Susan; Griego, Elizabeth

    A program was implemented to expand the curriculum materials within the Licensed Practical Nursing (LPN) Program at Clark County Community College (CCCC) which relate to oral hygiene care for the hospital patient. The instructional materials included a video tape and a written instructional packet which were researched, prepared, and presented by…

  19. Expanding Technological Frames Towards Mediated Collaboration

    DEFF Research Database (Denmark)

    Bjørn, Pernille; Scupola, Ada; Fitzgerald, Brian

    2006-01-01

    This paper provides an in-depth analysis of technological and social factors leading to the successful adoption of groupware in a virtual team in educational setting. Drawing on a theoretical framework based on the concept of technological frames, we conducted an action research study to analyze...... the chronological sequence of events leading to groupware adoption. We argue that groupware adoption can be conceptualized as a three-step process of expanding and aligning individual technological frames towards groupware: The first step comprises activities facilitating participants in articulation and evaluation...... collaborative practice and use of technology, and that this activity cannot take place at the outset....

  20. Multiparticle dynamics in an expanding universe

    Science.gov (United States)

    Anderson, James L.

    1995-11-01

    Approximate equations of motion for multiparticle systems in an expanding Einstein-deSitter universe are derived from the Einstein-Maxwell field equations using the Einstein-Infeld-Hoffmann surface integral method. At the Newtonian level of approximation one finds that, in comoving coordinates, both the Newtonian gravitational and Coulomb interactions in these equations are multiplied by the inverse third power of the scale factor R(t) appearing in the Einstein-deSitter field and they acquire a cosmic ``drag'' term. Nevertheless, both the period and luminosity size of bound two-body systems whose period is small compared to the Hubble time are found to be independent of t.