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Sample records for vessel lumen diameter

  1. An ecophysiological and developmental perspective on variation in vessel diameter.

    Science.gov (United States)

    Hacke, Uwe G; Spicer, Rachel; Schreiber, Stefan G; Plavcová, Lenka

    2017-06-01

    Variation in xylem vessel diameter is one of the most important parameters when evaluating plant water relations. This review provides a synthesis of the ecophysiological implications of variation in lumen diameter together with a summary of our current understanding of vessel development and its endogenous regulation. We analyzed inter-specific variation of the mean hydraulic vessel diameter (D v ) across biomes, intra-specific variation of D v under natural and controlled conditions, and intra-plant variation. We found that the D v measured in young branches tends to stay below 30 µm in regions experiencing winter frost, whereas it is highly variable in the tropical rainforest. Within a plant, the widest vessels are often found in the trunk and in large roots; smaller diameters have been reported for leaves and small lateral roots. D v varies in response to environmental factors and is not only a function of plant size. Despite the wealth of data on vessel diameter variation, the regulation of diameter is poorly understood. Polar auxin transport through the vascular cambium is a key regulator linking foliar and xylem development. Limited evidence suggests that auxin transport is also a determinant of vessel diameter. The role of auxin in cell expansion and in establishing longitudinal continuity during secondary growth deserve further study. © 2016 John Wiley & Sons Ltd.

  2. Photoacoustic determination of blood vessel diameter

    NARCIS (Netherlands)

    Kolkman, R.G.M.; Klaessens, John H.G.M.; Hondebrink, Erwin; Hopman, Jeroen C.W.; de Mul, F.F.M.; Steenbergen, Wiendelt; Thijssen, Johan M.; van Leeuwen, Ton

    2004-01-01

    A double-ring sensor was applied in photoacoustic tomographic imaging of artificial blood vessels as well as blood vessels in a rabbit ear. The peak-topeak time (τ pp) of the laser (1064 nm) induced pressure transient was used to estimate the axial vessel diameter. Comparison with the actual vessel

  3. Retinal vessel diameters and risk of stroke: the Rotterdam Study

    NARCIS (Netherlands)

    Ikram, M. K.; de Jong, F. J.; Bos, M. J.; Vingerling, J. R.; Hofman, A.; Koudstaal, P. J.; de Jong, P. T. V. M.; Breteler, M. M. B.

    2006-01-01

    Retinal vessels may provide information on cerebral vascular pathology, because they share many features with cerebral vessels. A smaller ratio of the retinal arteriolar-to-venular diameters reportedly predicts the risk of stroke. It is unclear if this is due to arteriolar narrowing or venular

  4. COMPARISON OF FLUOROSCOPY AND COMPUTED TOMOGRAPHY FOR TRACHEAL LUMEN DIAMETER MEASUREMENT AND DETERMINATION OF INTRALUMINAL STENT SIZE IN HEALTHY DOGS.

    Science.gov (United States)

    Williams, Jackie M; Krebs, Ingar A; Riedesel, Elizabeth A; Zhao, Qianqian

    2016-05-01

    Tracheal collapse is a progressive airway disease that can ultimately result in complete airway obstruction. Intraluminal tracheal stents are a minimally invasive and viable treatment for tracheal collapse once the disease becomes refractory to medical management. Intraluminal stent size is chosen based on the maximum measured tracheal diameter during maximum inflation. The purpose of this prospective, cross-sectional study was to compare tracheal lumen diameter measurements and subsequent selected stent size using both fluoroscopy and CT and to evaluate inter- and intraobserver variability of the measurements. Seventeen healthy Beagles were anesthetized and imaged with fluoroscopy and CT with positive pressure ventilation to 20 cm H2 O. Fluoroscopic and CT maximum tracheal diameters were measured by three readers. Three individual measurements were made at eight predetermined tracheal sites for dorsoventral (height) and laterolateral (width) dimensions. Tracheal diameters and stent sizes (based on the maximum tracheal diameter + 10%) were analyzed using a linear mixed model. CT tracheal lumen diameters were larger compared to fluoroscopy at all locations (P-value fluoroscopy compared to CT, both within and among observers. The greater tracheal diameter measured with CT and lower measurement variability has clinical significance, as this may be the imaging modality of choice for appropriate stent selection to minimize complications in veterinary patients. © 2016 American College of Veterinary Radiology.

  5. High-resolution computed tomography evaluation of the bronchial lumen to vertebral body diameter and pulmonary artery to vertebral body diameter ratios in anesthetized ventilated normal cats.

    Science.gov (United States)

    Lee-Fowler, Tekla M; Cole, Robert C; Dillon, A Ray; Tillson, D Michael; Garbarino, Rachel; Barney, Sharron

    2017-10-01

    Objectives Bronchial lumen to pulmonary artery diameter (BA) ratio has been utilized to investigate pulmonary pathology on high-resolution CT images. Diseases affecting both the bronchi and pulmonary arteries render the BA ratio less useful. The purpose of the study was to establish bronchial lumen diameter to vertebral body diameter (BV) and pulmonary artery diameter to vertebral body diameter (AV) ratios in normal cats. Methods Using high-resolution CT images, 16 sets of measurements (sixth thoracic vertebral body [mid-body], each lobar bronchi and companion pulmonary artery diameter) were acquired from young adult female cats and 41 sets from pubertal female cats. Results Young adult and pubertal cat BV ratios were not statistically different from each other in any lung lobe. Significant differences between individual lung lobe BV ratios were noted on combined age group analysis. Caudal lung lobe AV ratios were significantly different between young adult and pubertal cats. All other lung lobe AV ratios were not significantly different. Caudal lung lobe AV ratios were significantly different from all other lung lobes but not from each other in both the young adult and pubertal cats. Conclusions and relevance BV ratio reference intervals determined for individual lung lobes could be applied to both young adult and pubertal cats. Separate AV ratios for individual lung lobes would be required for young adult and pubertal cats. These ratios should allow more accurate evaluation of cats with concurrent bronchial and pulmonary arterial disease.

  6. Assessment of vessel diameters for MR brain angiography processed images

    Science.gov (United States)

    Moraru, Luminita; Obreja, Cristian-Dragos; Moldovanu, Simona

    2015-12-01

    The motivation was to develop an assessment method to measure (in)visible differences between the original and the processed images in MR brain angiography as a method of evaluation of the status of the vessel segments (i.e. the existence of the occlusion or intracerebral vessels damaged as aneurysms). Generally, the image quality is limited, so we improve the performance of the evaluation through digital image processing. The goal is to determine the best processing method that allows an accurate assessment of patients with cerebrovascular diseases. A total of 10 MR brain angiography images were processed by the following techniques: histogram equalization, Wiener filter, linear contrast adjustment, contrastlimited adaptive histogram equalization, bias correction and Marr-Hildreth filter. Each original image and their processed images were analyzed into the stacking procedure so that the same vessel and its corresponding diameter have been measured. Original and processed images were evaluated by measuring the vessel diameter (in pixels) on an established direction and for the precise anatomic location. The vessel diameter is calculated using the plugin ImageJ. Mean diameter measurements differ significantly across the same segment and for different processing techniques. The best results are provided by the Wiener filter and linear contrast adjustment methods and the worst by Marr-Hildreth filter.

  7. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit

    2006-01-01

    for CRVE, and 0.67 +/- 0.05 microm for AVR. No significant influence on artery or vein diameters was found for gender, smoking, body mass index (BMI), total cholesterol, fasting blood glucose, or 2-hour oral glucose tolerance test values. CONCLUSIONS: In healthy young adults with normal blood pressure......PURPOSE: To assess the relative influence of genetic and environmental effects on retinal vessel diameters and blood pressure in healthy adults, as well as the possible genetic connection between these two characteristics. METHODS: In 55 monozygotic and 50 dizygotic same-sex healthy twin pairs......%-80%) for CRAE, 83% (95% CI: 73%-89%) for CRVE, and 61% (95% CI: 44%-73%) for mean arterial blood pressure (MABP). Retinal artery diameter decreased with increasing age and increasing arterial blood pressure. Mean vessel diameters in the population were 165.8 +/- 14.9 microm for CRAE, 246.2 +/- 17.7 microm...

  8. Visual function and retinal vessel diameters during hyperthermia in man

    DEFF Research Database (Denmark)

    Jensen, Bettina Hagström; Bram, Thue; Kappelgaard, Per

    2017-01-01

    .01), a 10.6-mmHg mean reduction in diastolic blood pressure (p vein...... laser ophthalmoscopy was used to measure retinal trunk vessel diameters. Assessment was made at baseline, during hyperthermia and after cooling. RESULTS: The induction of a mean increase in core body temperature of 1.02°C was associated with a 7.15-mmHg mean reduction in systolic blood pressure (p

  9. Pengaruh Pemberian Triheksifenidil Dosis Bertingkat Per Oral terhadap Diameter Lumen Tubulus Ginjal Mus Musculus

    Directory of Open Access Journals (Sweden)

    Devangga Kusuma

    2018-01-01

    Full Text Available Triheksifenidil adalah golongan obat antikolinergik. Penyalahgunaan triheksifenidil meningkat dalam beberapa tahun terakhir. Penggunaan triheksifenidil dosis tinggi dapat menyebabkan retensi urin. Namun, sampai saat ini belum ada data mengenai gambaran histopatologi yang dapat terjadi pada ginjal, apabila triheksifenidil digunakan secara berlebihan. Penelitian ini merupakan penelitian eksperimental laboratorik dengan post test only control group design. Sampel penelitian menggunakan hewan coba 36 mencit (Mus musculus yang dibagi menjadi 4 kelompok. Kelompok kontrol terdiri dari satu kelompok yang hanya diberi pakan standar. Sedangkan kelompok perlakuan terdiri dari tiga kelompok yang diberi triheksifenidil dengan dosis 0,0208 mg/20 gramBB/hari, 0,0416 mg/20 gramBB/hari dan 0,0624 mg/20 gramBB/hari selama 14 hari. Hasil penelitian menunjukkan bahwa terdapat perbedaan signifikan diameter tubulus proksimal mencit antara kelompok kontrol dan perlakuan. Pada kelompok perlakuan, diameter tubulus proksimal menurun sebanding dengan dosis pemberian. Diameter tubulus proksimal paling rendah didapatkan pada kelompok perlakuan 3, dibandingkan dengan kelompok lainnya. Kata Kunci: Triheksifenidil, Histopatologi Ginjal, Tubulus Proksimal

  10. Effects of cryopreservation on excretory function, cellular adhesion molecules and vessel lumen formation in human umbilical vein endothelial cells.

    Science.gov (United States)

    Cai, Guoping; Lai, Binbin; Hong, Huaxing; Lin, Peng; Chen, Weifu; Zhu, Zhong; Chen, Haixiao

    2017-07-01

    Cryopreservation is widely used in regenerative medicine for tissue preservation. In the present study, the effects of cryopreservation on excretory function, cellular adhesion molecules and vessel lumen formation in human umbilical vein endothelial cells (HUVECs) were investigated. After 0, 4, 8, 12 or 24 weeks of cryopreservation in liquid nitrogen, the HUVECs were thawed. The excretory functions markers (endothelin‑1, prostaglandin E1, von Willebrand factor and nitric oxide) of HUVECs were measured by ELISA assay. The expression of intercellular adhesion molecule‑1 (ICAM‑1) in HUVECs was analyzed using flow cytometry. An angiogenesis assay was used to determine the angiogeneic capabilities of the thawed HUVECs. The results demonstrated that cryopreserved/thawed and recultivated HUVECs were unsuitable for tissue‑engineered microvascular construction. Specifically, the excretory function of the cells was significantly decreased in the post‑cryopreserved HUVECs at 24 weeks. In addition, the level of ICAM‑1 in HUVECs was significantly upregulated from the fourth week of cryopreservation. Furthermore, the tube‑like structure‑forming potential was weakened with increasing cryopreservation duration, and the numbers of lumen and the length of the pipeline were decreased in the thawed HUVECs, in a time‑dependent manner. In conclusion, the results of the present study revealed that prolonged cryopreservation may lead to HUVEC dysfunction and did not create stable cell lines for tissue‑engineered microvascular construction.

  11. Xylem Vessel Diameter Affects the Compartmentalization of the Vascular Pathogen Phaeomoniella chlamydospora in Grapevine

    Directory of Open Access Journals (Sweden)

    Jérôme Pouzoulet

    2017-08-01

    Full Text Available Fungal wilt diseases are a threat to global food safety. Previous studies in perennial crops showed that xylem vessel diameter affects disease susceptibility. We tested the hypothesis that xylem vessel diameter impacts occlusion processes and pathogen compartmentalization in Vitis vinifera L. We studied the interaction between four grape commercial cultivars with the vascular wilt pathogen Phaeomoniella chlamydospora. We used qPCR and wood necrotic lesion length to measure fungal colonization coupled with histological studies to assess differences in xylem morphology, pathogen compartmentalization, and fungal colonization strategy. We provided evidence that grape cultivar with wide xylem vessel diameter showed increased susceptibility to P. chlamydospora. The host response to pathogen included vessel occlusion with tyloses and gels, deposition of non-structural phenolic compounds and suberin in vessel walls and depletion of starch in parenchyma cells. Pathogen compartmentalization was less efficient in wide xylem vessels than in narrow diameter vessels. Large vessels displayed higher number of tyloses and gel pockets, which provided substrate for P. chlamydospora growth and routes to escape occluded vessels. We discuss in which capacity xylem vessel diameter is a key determinant of the compartmentalization process and in turn grape cultivar resistance to disease caused by P. chlamydospora.

  12. Analysis of pressurized resistance vessel diameter changes with a low cost digital image processing device.

    Science.gov (United States)

    Fischer, J G; Mewes, H; Hopp, H H; Schubert, R

    1996-06-01

    A low cost digital image processing device (frame grabber) together with a program running under MS_WINDOWS for automatic on-line analysis of diameter changes of in vitro pressurized blood vessels with an inner diameter of 80-400 microns is presented. The frame grabber is designed to receive light microscopic images either from a video camera or from a VCR and to present the digitized image on the computer monitor. The special software allows to manipulate the image, e.g. filtering, calibrating, storing of vessel images, and detects the outer and inner border of the two vessel walls with a new, simple algorithm. The inner diameter and the vessel wall thickness are calculated and the diameter is presented in a diameter versus time diagram on the monitor screen. Further, these data are stored in an ASCII-file for later import into calculation and presentation programs like MS-EXCEL.

  13. Estimation of vessel diameter and blood flow dynamics from laser speckle images

    DEFF Research Database (Denmark)

    Postnov, Dmitry D.; Tuchin, Valery V.; Sosnovtseva, Olga

    2016-01-01

    Laser speckle imaging is a rapidly developing method to study changes of blood velocity in the vascular networks. However, to assess blood flow and vascular responses it is crucial to measure vessel diameter in addition to blood velocity dynamics. We suggest an algorithm that allows for dynamical...... masking of a vessel position and measurements of it's diameter from laser speckle images. This approach demonstrates high reliability and stability....

  14. Web-based accurate measurements of carotid lumen diameter and stenosis severity: An ultrasound-based clinical tool for stroke risk assessment during multicenter clinical trials.

    Science.gov (United States)

    Saba, Luca; Banchhor, Sumit K; Londhe, Narendra D; Araki, Tadashi; Laird, John R; Gupta, Ajay; Nicolaides, Andrew; Suri, Jasjit S

    2017-12-01

    This pilot study presents a completely automated, novel, smart, cloud-based, point-of-care system for (a) carotid lumen diameter (LD); (b) stenosis severity index (SSI) and (c) total lumen area (TLA) measurement using B-mode ultrasound. The proposed system was (i) validated against manual reading taken by the Neurologist and (ii) benchmarked against the commercially available system. One hundred patients (73 M/27 F, mean age: 68 ± 11 years), institutional review board approved, written informed consent, consisted of left/right common carotid artery (200 ultrasound scans) were acquired using a 7.5-MHz linear transducer. The measured mean LD for left and right carotids were (in mm): (i) for proposed system (6.49 ± 1.77, 6.66 ± 1.70); and (ii) for manual (6.29 ± 1.79, 6.45 ± 1.63), respectively and coefficient of correlation between cloud-based automated against manual were 0.98 (P cloud-based system was: 1.0. Four statistical tests such as: Two-tailed z-test, Mann-Whitney test, Kolmogorov-Smirnov (KS) and one-way ANOVA were performed to demonstrate consistency and reliability. The proposed system is reliable, accurate, fast, completely automated, anytime-anywhere solution for multi-center clinical trials and routine vascular screening. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. The design of lifting attachments for the erection of large diameter and heavy wall pressure vessels

    International Nuclear Information System (INIS)

    Antalffy, Leslie P.; Miller, George A.; Kirkpatrick, Kenneth D.; Rajguru, Anil; Zhu, Yong

    2016-01-01

    Lifting attachments for the erection of large diameter and heavy wall pressure vessels require special consideration to ensure that their attachment to their vessel shells or heads do not overstress the vessel during the erection process when lifting these from grade onto their respective foundations. Today, in refinery and petrochemical services, large diameter vessels with diameters ranging up to 15 m and reactors with lifting weights in the range of 700–1400 tons are not uncommon. In today's fabrication market, these vessels may be purchased and fabricated in shops dispersed globally and will require unique equipment for their safe handling, transportation and subsequent erection. The challenge is to design the lifting attachments in such a manner that the attachments provide a safe, cost effective and effective solution based upon the limitations of the job site lift equipment available for erection. Such equipment for the transportation and subsequent lifting of large diameter and heavy wall pressure equipment is usually scarce and quite expensive. Planning ahead, well in advance of the lift date is almost a mandatory requirement. Usually, the specific parameters of the vessel to be lifted and the lifting equipment available at the site will dictate the type of lifting attachments to be designed for the vessel. Once the type of vessel attachment has been chosen, careful consideration must be given to the design of attachments to the pressure vessel in consideration to ensure that the vessel and lifting components are not overstressed during the lifting process. The paper also discusses different types of lifting attachments that may be attached to each end of the vessel either by bolting or welding and discusses the pros and cons of each. The paper also provides an example of a finite element analysis (FEA) of a top nozzle, a FEA of a pair of lifting trunnions and a FEA of welded on lifting lugs for buried pipe. The purpose of the paper is to outline

  16. Relationship of the duke jeopardy score combined with minimal lumen diameter as assessed by computed tomography angiography to the hemodynamic relevance of coronary artery stenosis.

    Science.gov (United States)

    Yu, Mengmeng; Zhao, Yonghong; Li, Wenbin; Lu, Zhigang; Wei, Meng; Zhou, Wenxiao; Zhang, Jiayin

    2018-03-02

    To study the diagnostic performance of the ratio between the Duke jeopardy score (DJS) and the minimal lumen diameter (MLD) (DJS/MLD CT ratio) as assessed by coronary computed tomographic angiography (CTA) for differentiating functionally significant from non-significant coronary artery stenoses, with reference to invasive fractional flow reserve (FFR). Patients who underwent both coronary CTA and FFR measurement during invasive coronary angiography (ICA) within 2 weeks were retrospectively included in the study. Invasive FFR measurement was performed in patients with intermediate to severe coronary stenoseis. DJS/MLD CT ratio and anatomical parameters were recorded. Lesions with FFR ≤0.80 were considered to be functionally significant. One hundred and sixty-one patients with 175 lesions were included into the analysis. Diameter stenosis in CT, area stenosis, plaque burden, lesion length (LL), ICA-based stenosis degree, DJS, LL/MLD 4 ratio, DJS/MLA ratio as well as DJS/MLD ratio were all significantly different between hemodynamically significant and non-significant lesions (pvalue for DJS/MLD CT ratio to be 1.96 (area under curve = 0.863, 95 % confidence interval = 0.803-0.910), yielding a high diagnostic accuracy (86.9%, 152/175). In coronary artery stenoses detected by coronary CTA, the DJS/MLD ratio is able to predict hemodynamic relevance. Copyright © 2018 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

  17. Quantitative measurement of changes in retinal vessel diameter in ocular fundus images

    DEFF Research Database (Denmark)

    Pedersen, Lars; Grunkin, Michael; Ersbøll, Bjarne Kjær

    2000-01-01

    The change in diameter of retinal vessels as a function of increasing distance to the optic disc is believed to be indicative of the risk level of various vascular diseases such as generalised arteriosclerosis and Diabetes Mellitus. In particular, focal arteriolar narrowing (FAN) is considered re...

  18. Quantitative Measurement of Changes in Retinal Vessel Diameter in Ocular Fundus Images

    DEFF Research Database (Denmark)

    Pedersen, Lars; Grunkin, Michael; Ersbøll, Bjarne Kjær

    1999-01-01

    The Change in diameter of retinal vessels as a funcion of increasing distance to the optic disc is believed to be indicative of the risk level of various vascular diseases such as generalised arteriosclerosis and Diabetes Mellitus. In particular, Focal Arteriolar Narrowing (FAN) is considered...

  19. Automatic evaluation of vessel diameter variation from 2D X-ray angiography.

    Science.gov (United States)

    M'hiri, Faten; Duong, Luc; Desrosiers, Christian; Dahdah, Nagib; Miró, Joaquim; Cheriet, Mohamed

    2017-11-01

    Early detection of blood vessel pathologies can be made through the evaluation of functional and structural abnormalities in the arteries, including the arterial distensibility measure. We propose a feasibility study on computing arterial distensibility automatically from monoplane 2D X-ray sequences for both small arteries (such as coronary arteries) and larger arteries (such as the aorta). To compute the distensibility measure, three steps were developed: First, the segment of an artery is extracted using our graph-based segmentation method. Then, the same segment is tracked in the moving sequence using our spatio-temporal segmentation method: the Temporal Vessel Walker. Finally, the diameter of the artery is measured automatically at each frame of the sequence based on the segmentation results. The method was evaluated using one simulated sequence and 4 patients' angiograms depicting the coronary arteries and three depicting the ascending aorta. Results of the simulated sequence achieved a Dice index of 98%, with a mean squared error in diameter measurement of [Formula: see text] mm. Results obtained from patients' X-ray sequences are consistent with manual assessment of the diameter by experts. The proposed method measures changes in diameter of a specific segment of a blood vessel during the cardiac sequence, automatically based on monoplane 2D X-ray sequence. Such information might become a key to help physicians in the detection of variations of arterial stiffness associated with early stages of various vasculopathies.

  20. Relationship between retinal vessel diameters and retinopathy in the Inter99 Eye Study

    DEFF Research Database (Denmark)

    Drobnjak, Dragana; Munch, Inger Christine; Glümer, Charlotte

    2017-01-01

    was 6.3 µm (CI 95%: 1.0 to 11.6, p = 0.020) wider and CRVE was 7.9 µm (CI 95%: 0.7 to 15.2, p = 0.030) wider in those with retinopathy compared to those without retinopathy, after adjusting for age, gender, HbA1c, blood pressure, smoking, serum total and HDL cholesterol. In all participants, CRAE...... of one or more retinal hemorrhages or one or more microaneurysms. Vessel diameters were expressed as central retinal artery equivalent diameter (CRAE) and central retinal vein equivalent diameter (CRVE). Multiple linear regression analyses were performed. RESULTS: Among participants with diabetes, CRAE...... increased with presence of retinopathy (p = 0.005) and with smoking (p = 0.001), and CRAE decreased with hypertension (p vein equivalent diameter increased with presence of retinopathy (p = 0.022) and with smoking (p

  1. Estimation of center line and diameter of brain blood vessel using three-dimensional blood vessel matching method with head three-dimensional CTA image

    International Nuclear Information System (INIS)

    Maekawa, Masashi; Shinohara, Toshihiro; Nakayama, Masato; Nakasako, Noboru

    2010-01-01

    To support and automate the brain blood vessel disease diagnosis, a novel method to obtain the center line and the diameter of a blood vessel is proposed with a three-dimensional head computed tomographic angiography (CTA) image. Although the line thinning processing with distance transform or gray information is generally used to obtain the blood vessel center line, this method is not essentially one to obtain the center line and tends to yield extra lines depending on CTA images. In this study, the center line of the blood vessel is obtained by tracing the vessel. The blood vessel is traced by sequentially estimating the center point and direction of the blood vessel. The center point and direction of the blood vessel are estimated by taking the correlation between the blood vessel and a solid model of the blood vessel that is designed by considering noise influence. In addition, the vessel diameter is also estimated by correlating the blood vessel and the blood vessel model of which the diameter is variable. The validity of the proposed method is confirmed by experimentally applied the proposed method to an actual three-dimensional head CTA image. (author)

  2. Stenting vs. balloon angioplasty with provisional stenting for the treatment of vessels with small reference diameter.

    Science.gov (United States)

    Lemos, Pedro A; Martinez, Eulogio E; Quintella, Edgard; Harrell, Lari C; Ramires, Jose A F; Ribeiro, Expedito E; da Gama, Marcus N; Horta, Pedro E; Kajita, Luiz J; Esteves, Antonio; Perin, Marco A; Soares, Paulo R; Zalc, Silvio; Palacios, Igor F

    2002-03-01

    A consecutive series of interventions in vessels with reference diameter < or = 2.75 mm was retrospectively analyzed according to preprocedure strategy: balloon angioplasty with provisional stenting (PTCA group, 73 patients) and primary stenting (PS group, 122 patients). In the PS group, there were more patients with single-vessel disease (54.1% vs. 37.0%; P = 0.021), less patients with three-vessel disease (9.0% vs. 24.7%; P = 0.003), more LAD interventions (54.9% vs. 31.5; P = 0.002), and less left circumflex interventions (22.1% vs. 45.2%; P < 0.001). Reference diameter was larger in the PS group (2.28 +/- 0.35 mm vs. 2.11 +/- 0.36 mm; P = 0.001). Provisional stenting was performed in 39.7% of PTCA group. At long-term outcome, the incidence of composite major events was similar between the PTCA and the PS groups (20.5% vs. 17.2%, respectively; P = NS). Treatment of small vessels with balloon dilatation and provisional stenting or with primary stenting yielded similar late outcomes. Operators' choice of treatment strategy was based on particular angiographic characteristics. Copyright 2002 Wiley-Liss, Inc.

  3. A simply prepared small-diameter artificial blood vessel that promotes in situ endothelialization.

    Science.gov (United States)

    Guo, Hong-Feng; Dai, Wei-Wei; Qian, De-Hui; Qin, Zhe-Xue; Lei, Yan; Hou, Xiao-Yu; Wen, Can

    2017-05-01

    Synthetic grafts are of limited use in small-diameter vessels (Φartificial blood vessels with the aim of facilitating early endothelialization and improving long-term patency. STATEMENT OF SIGNIFICANCE: (1) SDF-1α/VEGF loaded PU conduits were simply prepared by electrospinning. The cytokines with definite and potent effects on angiogenesis were used to avoid complicated mechanism researches. Compared with most of the current vascular grafts which are of poor strength or elasticity, the conduits have favorable mechanical property. All of these inhibit the conduits from occlusion, and thus improve their long-term patency rate. (2) For the in vivo tests, the dogs did not receive any anticoagulant medication in the follow-up period to expose the grafts to the strictest conditions. In vivo endothelialization of the conduits was thoroughly investigated by Sonography, HE staining, SEM and LSCM. The study will be helpful for the construction of small-diameter artificial blood vessels. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  4. Automated detection of vessel lumen and stent struts in intravascular optical coherence tomography to evaluate stent apposition and neointimal coverage

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Hyeong Soo; Kim, Chang-Soo; Yoo, Hongki, E-mail: kjwmm@korea.ac.kr, E-mail: hyoo@hanyang.ac.kr [Department of Biomedical Engineering, Hanyang University, Seoul 04763 (Korea, Republic of); Lee, Jae Joong; Song, Joon Woo; Kim, Jin Won, E-mail: kjwmm@korea.ac.kr, E-mail: hyoo@hanyang.ac.kr [Division of Interventional Cardiology, Cardiovascular Center, Korea University Guro Hospital, Seoul 08308 (Korea, Republic of)

    2016-04-15

    Purpose: Intravascular optical coherence tomography (IV-OCT) is a high-resolution imaging method used to visualize the microstructure of arterial walls in vivo. IV-OCT enables the clinician to clearly observe and accurately measure stent apposition and neointimal coverage of coronary stents, which are associated with side effects such as in-stent thrombosis. In this study, the authors present an algorithm for quantifying stent apposition and neointimal coverage by automatically detecting lumen contours and stent struts in IV-OCT images. Methods: The algorithm utilizes OCT intensity images and their first and second gradient images along the axial direction to detect lumen contours and stent strut candidates. These stent strut candidates are classified into true and false stent struts based on their features, using an artificial neural network with one hidden layer and ten nodes. After segmentation, either the protrusion distance (PD) or neointimal thickness (NT) for each strut is measured automatically. In randomly selected image sets covering a large variety of clinical scenarios, the results of the algorithm were compared to those of manual segmentation by IV-OCT readers. Results: Stent strut detection showed a 96.5% positive predictive value and a 92.9% true positive rate. In addition, case-by-case validation also showed comparable accuracy for most cases. High correlation coefficients (R > 0.99) were observed for PD and NT between the algorithmic and the manual results, showing little bias (0.20 and 0.46 μm, respectively) and a narrow range of limits of agreement (36 and 54 μm, respectively). In addition, the algorithm worked well in various clinical scenarios and even in cases with a low level of stent malapposition and neointimal coverage. Conclusions: The presented automatic algorithm enables robust and fast detection of lumen contours and stent struts and provides quantitative measurements of PD and NT. In addition, the algorithm was validated using

  5. Optical coherence tomography and vessel diameter changes after intravitreal bevacizumab in diabetic macular oedema

    DEFF Research Database (Denmark)

    Soliman, W.; Vinten, M.; Sander, B.

    2008-01-01

    Purpose: To assess the effect of intravitreal bevacizumab on diabetic macular oedema (DMO) and retinal vessel calibres. Methods: We performed a consecutive case series study in which 10 consecutive eyes with diffuse DMO, two of which had not previously been treated, received an intravitreal...... injection of bevacizumab 1 mg, which was followed by two more injections at 6-week intervals. Fundus photography and optical coherence tomography (OCT) were carried out at baseline immediately before injection and at 1, 2.5 and 4 months after the first injection. Outcome measures were best corrected visual...... acuity (BCVA) in Early Treatment Diabetic Retinopathy Study letters, macular volume, foveal subfield thickness and vessel diameter measurement. Results: Intravitreal administration of bevacizumab was followed by a mean increase in BCVA of 7.3 +/- 17 (mean +/- standard deviation) letters between baseline...

  6. Electrospun Fibrous Scaffolds for Small-Diameter Blood Vessels: A Review

    Directory of Open Access Journals (Sweden)

    Nasser K. Awad

    2018-03-01

    Full Text Available Small-diameter blood vessels (SDBVs are still a challenging task to prepare due to the occurrence of thrombosis formation, intimal hyperplasia, and aneurysmal dilation. Electrospinning technique, as a promising tissue engineering approach, can fabricate polymer fibrous scaffolds that satisfy requirements on the construction of extracellular matrix (ECM of native blood vessel and promote the adhesion, proliferation, and growth of cells. In this review, we summarize the polymers that are deployed for the fabrication of SDBVs and classify them into three categories, synthetic polymers, natural polymers, and hybrid polymers. Furthermore, the biomechanical properties and the biological activities of the electrospun SBVs including anti-thrombogenic ability and cell response are discussed. Polymer blends seem to be a strategic way to fabricate SDBVs because it combines both suitable biomechanical properties coming from synthetic polymers and favorable sites to cell attachment coming from natural polymers.

  7. Control of weft yarn or density improves biocompatibility of PET small diameter artificial blood vessels.

    Science.gov (United States)

    Hu, Xingyou; Hu, Tao; Guan, Guoping; Yu, Shaoting; Wu, Yufen; Wang, Lu

    2018-04-01

    Polyethylene glycol terephthalate (PET) fabrics with woven structures have proved to be quite effective for use on large diameter artificial blood vessels. However, their use within small-diameter artificial blood vessels has been associated with poor long-term patency, a problem resulting from slow endothelialization on PET and an over hyperplasia of smooth muscle cells. Previous research from our laboratory has revealed that ICAM-1 can be used as a marker to investigate cell adhesion, an effect which was closely associated with cell behavior on the surface of polycaprolactone (PCL) films. Moreover, we found that the coarseness or pore size of the surface exerts considerable influence on cell adhesion and proliferation on PCL films. In this study, we successfully fabricated six types of PET woven fabrics with varying gradients of tightness and porosities. Levels of ICAM-1 expression (membrane ICAM-1 & soluble ICAM-1) were then determined in these woven fabrics. Our results show that increased levels of mICAM-1 and decreased levels of sICAM-1 expression were obtained in HUVECs seeded on these six samples. These findings indicate that cell adhesion and proliferation on fabric surfaces were strongly influenced by their structural parameters, in particular the initial adhesion between the cell and fabric surface. In addition, we also found that extracellular matrix adhesion tends to prefer flat and tight surfaces, which promotes cell-cell and cell-matrix interactions, as well as the endothelialization on the surface of PET fabrics. These findings provide some novel insights with regard to the design and application of small-diameter artificial blood vessels. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 954-964, 2018. © 2017 Wiley Periodicals, Inc.

  8. Pulmonary artery pulsatility and effect on vessel diameter assessment in magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Shariat, Masoud, E-mail: masoudshariat@gmail.com [Department of Medical Imaging, University Health Network, University of Toronto, Toronto, Ontario (Canada); Department of Diagnostic Imaging, Hospital for Sick Children, Toronto, Ontario (Canada); Schantz, Daryl, E-mail: daryl.schantz@gmail.com [Department of Diagnostic Imaging, Hospital for Sick Children, Toronto, Ontario (Canada); Yoo, Shi-Joon, E-mail: shi-joon.yoo@sickkids.ca [Department of Diagnostic Imaging, Hospital for Sick Children, Toronto, Ontario (Canada); Wintersperger, Bernd J., E-mail: bernd.wintersperger@uhn.ca [Department of Medical Imaging, University Health Network, University of Toronto, Toronto, Ontario (Canada); Seed, Mike, E-mail: mike.seed@sickkids.ca [Department of Diagnostic Imaging, Hospital for Sick Children, Toronto, Ontario (Canada); Department of Cardiology, Hospital for Sick Children, Toronto, Ontario (Canada); Alnafisi, Bahiyah, E-mail: bahiyah.alnafisi@uhn.ca [Department of Medical Imaging, University Health Network, University of Toronto, Toronto, Ontario (Canada); Chu, Leysia, E-mail: leysia_99@yahoo.com [Department of Diagnostic Imaging, Hospital for Sick Children, Toronto, Ontario (Canada); MacGowan, Christopher K., E-mail: christopher.macgowan@sickkids.ca [Department of Physiology and Experimental Medicine, Hospital for Sick Children, Toronto, Ontario (Canada); Amerom, Joshua van, E-mail: Joshu.vanamerom@sickkids.ca [Department of Physiology and Experimental Medicine, Hospital for Sick Children, Toronto, Ontario (Canada); Grosse-Wortmann, Lars, E-mail: lars.grosse-wortmann@sickkids.ca [Department of Diagnostic Imaging, Hospital for Sick Children, Toronto, Ontario (Canada); Department of Cardiology, Hospital for Sick Children, Toronto, Ontario (Canada)

    2014-02-15

    Background: Information about thoracic vascular sizes can crucially affect clinical decision-making in cardiovascular disease. A variety of imaging techniques such as catheter angiography, contrast enhanced computed tomography (CT) and cardiac magnetic resonance imaging (CMR) are routinely used to measure vascular diameters. Traditionally, CMR black blood sequences were the main anatomical tool for visualization of vascular anatomy and still are in many centers. More recently, the vessel diameters are measured on multiplanar reconstructions derived from static magnetic resonance angiography (MRA). This study was performed to investigate the variation of vessel diameter measurements on different CMR techniques with respect to their data acquisition scheme. Methods: We recruited two groups of patients for this prospective study. One group included patients with repaired tetralogy of Fallot (TOF), with at least moderate pulmonary insufficiency and another group of patients who underwent CMR as part of a diagnostic work-up for arrhythmogenic right ventricular cardiomyopathy (ARVC). Additional images of the right pulmonary artery (RPA) were acquired in the double inversion recovery (DIR) black blood, cine steady state free precession (SSFP) and MRA. All images were reviewed by two CMR trained readers using the electronic caliper provided within the picture archiving and communication system package. The maximum diameter of each artery was recorded in millimeters with up to one decimal point. Paired t-tests and Bland–Altman plots were used for comparison of measurements between different sequences. Results: A total of 52 patients were recruited for this study, 26 patients in the TOF group (15 males, age 12.55 ± 2.9) and 26 patients in the ARVC group (15 males, age 15.6 ± 2.3). In both groups, the RPA sizes were not significantly different between the DIR images and diastolic cine SSFP (p > 0.05). Measurements on DIR were significantly smaller than those made on

  9. Pulmonary artery pulsatility and effect on vessel diameter assessment in magnetic resonance imaging

    International Nuclear Information System (INIS)

    Shariat, Masoud; Schantz, Daryl; Yoo, Shi-Joon; Wintersperger, Bernd J.; Seed, Mike; Alnafisi, Bahiyah; Chu, Leysia; MacGowan, Christopher K.; Amerom, Joshua van; Grosse-Wortmann, Lars

    2014-01-01

    Background: Information about thoracic vascular sizes can crucially affect clinical decision-making in cardiovascular disease. A variety of imaging techniques such as catheter angiography, contrast enhanced computed tomography (CT) and cardiac magnetic resonance imaging (CMR) are routinely used to measure vascular diameters. Traditionally, CMR black blood sequences were the main anatomical tool for visualization of vascular anatomy and still are in many centers. More recently, the vessel diameters are measured on multiplanar reconstructions derived from static magnetic resonance angiography (MRA). This study was performed to investigate the variation of vessel diameter measurements on different CMR techniques with respect to their data acquisition scheme. Methods: We recruited two groups of patients for this prospective study. One group included patients with repaired tetralogy of Fallot (TOF), with at least moderate pulmonary insufficiency and another group of patients who underwent CMR as part of a diagnostic work-up for arrhythmogenic right ventricular cardiomyopathy (ARVC). Additional images of the right pulmonary artery (RPA) were acquired in the double inversion recovery (DIR) black blood, cine steady state free precession (SSFP) and MRA. All images were reviewed by two CMR trained readers using the electronic caliper provided within the picture archiving and communication system package. The maximum diameter of each artery was recorded in millimeters with up to one decimal point. Paired t-tests and Bland–Altman plots were used for comparison of measurements between different sequences. Results: A total of 52 patients were recruited for this study, 26 patients in the TOF group (15 males, age 12.55 ± 2.9) and 26 patients in the ARVC group (15 males, age 15.6 ± 2.3). In both groups, the RPA sizes were not significantly different between the DIR images and diastolic cine SSFP (p > 0.05). Measurements on DIR were significantly smaller than those made on

  10. Remote disconnect of 87'' diameter Conoseal joint applied to pressure vessel closures

    International Nuclear Information System (INIS)

    Forrest, G.

    The design of the Conoseal joint and its application for the pressure vessel closure are described. The tested joint was made of stainless steel-347. In helium testing, joints of 1/8'' to 87'' in dia showed leaks less than 10 -8 to 2.5x10 -8 cm 3 .s -1 depending on the joint diameter. The total time required for the remote disconnection of the joint segments by an air motor shortens the time needed for closure opening from 60 to 4 hours. Flange and joint packing materials are listed with a view to joint applications at various operating temperatures. (J.B.)

  11. Retinal vessel diameters in relation to hematocrit variation during acclimatization of highlanders to sea level altitude

    DEFF Research Database (Denmark)

    Kofoed, Peter Kristian; Sander, Birgit; Zubieta-Calleja, Gustavo

    2009-01-01

    PURPOSE: To examine variations in retinal vessel diameters during acclimatization of native highlanders to normobaric normoxia at sea level. METHODS: Fifteen healthy residents of the greater La Paz region in Bolivia (3600 m above sea level) were examined thrice over a 72-day period, after having...... traveled by airplane to Copenhagen, Denmark, near sea level. RESULTS: In the study subjects, hematocrit decreased from 49.6% (day 2) to 45.9% (P = 0.0066, day 23) and 41.7% (P ... diameters were indistinguishable from baseline after 72 days. No funduscopic signs of retinopathy were observed. Arterial blood pressure remained stable throughout the study. CONCLUSIONS: Although a 16% reduction in hematocrit occurred between days 2 and 72 after arrival at sea level, the only significant...

  12. Retinal vessel diameters and reactivity in diabetes mellitus and/or cardiovascular disease.

    Science.gov (United States)

    Heitmar, R; Lip, G Y H; Ryder, R E; Blann, A D

    2017-04-26

    Retinal vessel calibre and vascular dilation/constriction in response to flicker light provocation may provide a measure distinguishing patients suffering from diabetes mellitus and/or cardiovascular disease. One hundred and sixteen age and sex matched patients with diabetes mellitus (DM), cardiovascular disease (CVD) and both DM and CVD (DM + CVD) underwent systemic and intraocular pressure measurements. Retinal vessel calibres were assessed using a validated computer-based program to compute central retinal artery and vein equivalents (CRVE) from monochromatic retinal images. Vessel dilation and constriction responses to flicker light provocation were assessed by continuous retinal vessel diameter recordings. Plasma endothelial markers von Willebrand factor (vWf) and soluble E selectin (sEsel) were measured by ELISA. Retinal vessel calibres were comparable across groups but CRVE correlated significantly with disease duration in DM patients (r = 0.57, p < 0.001). Patients suffering DM only exhibited reduced arterial vasomotion at rest and reduced arterial constriction following flicker light induced vessel dilation compared to patients with CVD and those suffering both CVD + DM (p = 0.030). Patients suffering from CVD + DM exhibited significant differences between each flicker cycle in regards to arterial maximum constriction (p = 0.006) and time needed to reach arterial maximum dilation (p = 0.004), whereas the other two groups did not show such inconsistencies between individual flicker cycles. vWf was raised in CVD + DM compared to the other two groups (p ≤ 0.02), whilst sEsel was raised in CVD + DM compared to DM alone (p = 0.044). Dynamic retinal vascular calibres as obtained by continuous diameter measurements using flicker light provocation can reveal subtle differences between groups suffering from CVD with and without DM. This difference in reaction pattern and lack of arterial constriction in DM may provide a suitable marker to

  13. Analysis of Peripapillary Retinal Vessel Diameter in Unilateral Normal-Tension Glaucoma

    Directory of Open Access Journals (Sweden)

    Yong Un Shin

    2017-01-01

    Full Text Available Purpose. This study sought to analyze peripapillary retinal vessel diameter and evaluate its correlation with retinal nerve fiber layer (RNFL thickness in patients with unilateral normal-tension glaucoma (NTG. Methods. This retrospective study included 37 patients with unilateral NTG and 40 healthy controls. The unilateral NTG patients were selected based on RNFL photography and unilateral visual field (VF defects from the Humphrey central 30-2 threshold test. The central retinal arteriolar equivalent (CRAE and central retinal venular equivalent (CRVE were measured and calculated using retinal photographs and a computer-assisted calculation program. The RNFL thickness was measured using spectral domain optical coherence tomography. Results. The mean CRAE and CRVE were significantly narrower in the glaucomatous and fellow eyes of the unilateral NTG patients than they were in the normal subjects (p<0.001. There was no significant correlation between CRAE/CRVE and RNFL thickness. There was only a significant correlation between VF severity and RNFL thickness in unilateral NTG eyes. Conclusions. Both NTG-affected eyes and NTG-fellow eyes in the unilateral NTG patients had narrower central retinal vessel diameters than did the eyes of normal subjects. Our results show that vascular factors may play a role in the NTG pathogenesis.

  14. Retinal hemodynamic oxygen reactivity assessed by perfusion velocity, blood oximetry and vessel diameter measurements

    DEFF Research Database (Denmark)

    Klefter, Oliver Niels; Lauritsen, Anne Øberg; Larsen, Michael

    2015-01-01

    PURPOSE: To test the oxygen reactivity of a fundus photographic method of measuring macular perfusion velocity and to integrate macular perfusion velocities with measurements of retinal vessel diameters and blood oxygen saturation. METHODS: Sixteen eyes in 16 healthy volunteers were studied at two...... (ICC) and limits of agreement. RESULTS: Fifteen minutes of hyperoxia was accompanied by mean reductions in arterial and venous perfusion velocities of 14% and 16%, respectively (p = 0.0080; p = 0.0019), constriction of major arteries and veins by 5.5% and 8.2%, respectively (p ...). For perfusion velocities, short-term ICCs were 0.79-0.82 and long-term ICCs were 0.06-0.11. Intersession increases in blood glucose were associated with reductions in perfusion velocities (arterial p = 0.0067; venous p = 0.018). CONCLUSION: Oxygen reactivity testing supported that motion-contrast velocimetry...

  15. Retinal Oximetry and Vessel Diameter Measurements With a Commercially Available Scanning Laser Ophthalmoscope in Diabetic Retinopathy.

    Science.gov (United States)

    Blair, Norman P; Wanek, Justin; Felder, Anthony E; Joslin, Charlotte E; Kresovich, Jacob K; Lim, Jennifer I; Chau, Felix Y; Leiderman, Yannek; Shahidi, Mahnaz

    2017-10-01

    To test the hypothesis that retinal vascular diameter and hemoglobin oxygen saturation alterations, according to stages of diabetic retinopathy (DR), are discernible with a commercially available scanning laser ophthalmoscope (SLO). One hundred eighty-one subjects with no diabetes (No DM), diabetes with no DR (No DR), nonproliferative DR (NPDR), or proliferative DR (PDR, all had photocoagulation) underwent imaging with an SLO with dual lasers (532 nm and 633 nm). Customized image analysis software determined the diameters of retinal arteries and veins (DA and DV) and central retinal artery and vein equivalents (CRAE and CRVE). Oxygen saturations of hemoglobin in arteries and veins (SO2A and SO2V) were estimated from optical densities of vessels on images at the two wavelengths. Statistical models were generated by adjusting for effects of sex, race, age, eye, and fundus pigmentation. DA, CRAE, and CRVE were reduced in PDR compared to No DM (P ≤ 0.03). DV and CRVE were similar between No DM and No DR, but they were higher in NPDR than No DR (P ≤ 0.01). Effect of stage of disease on SO2A differed by race, being increased relative to No DM in NPDR and PDR in Hispanic participants only (P ≤ 0.02). Relative to No DM, SO2V was increased in NPDR and PDR (P ≤ 0.05). Alterations in retinal vascular diameters and SO2 by diabetic retinopathy stage can be detected with a widely available SLO, and covariates such as race can influence the results.

  16. LumenRECON Guidewire: Pilot Study of a Novel, Nonimaging Technology for Accurate Vessel Sizing and Delivery of Therapy in Femoropopliteal Disease.

    Science.gov (United States)

    Nair, Pradeep K; Carr, Jeffrey G; Bigelow, Brian; Bhatt, Deepak L; Berwick, Zachary C; Adams, George

    2018-01-01

    Proper vessel sizing during endovascular interventions is crucial to avoid adverse procedural and clinical outcomes. LumenRECON (LR) is a novel, nonimaging, 0.035-inch wire-based technology that uses the physics-based principle of Ohm's law to provide a simple, real-time luminal size while also providing a platform for therapy delivery. This study evaluated the accuracy, reliability, and safety of the LR system in patients presenting for a femoropopliteal artery intervention. This multicenter, prospective pilot study of 24 patients presenting for peripheral intervention compared LR measurements of femoropopliteal artery size to angiographic visual estimation, duplex ultrasound, quantitative angiography, and intravascular ultrasound. The primary effectiveness and safety end point was comparison against core laboratory adjudicated intravascular ultrasound values and major adverse events, respectively. Additional preclinical studies were also performed in vitro and in vivo in swine to determine the accuracy of the LR guidewire system. No intra- or postprocedure device-related adverse events occurred. A balloon or stent was successfully delivered in 12 patients (50%) over the LR wire. Differences in repeatability between successive LR measurements was 2.5±0.40% ( R 2 =0.96) with no significant bias. Differences in measurements of LR to other modalities were 0.5±1.7%, 5.0±1.8%, -1.5±2.0%, and 6.8±3.4% for intravascular ultrasound core laboratory, quantitative angiography, angiographic, and duplex ultrasound, respectively. This study demonstrates that through a physics-based principle, LR provides a real-time, safe, reproducible, and accurate vessel size of the femoropopliteal artery during intervention and can additionally serve as a conduit for therapy delivery over its wire-based platform. © 2018 American Heart Association, Inc.

  17. A study of magnification effect to precision of computerized diameter measurement of a 3-mm vessel phantom in cineangiograms

    International Nuclear Information System (INIS)

    Yanagihara, Yoshio; Sugahara, Tetsuo; Sugimoto, Naozou; Fukunishi, Yasunobu.

    1994-01-01

    To estimate influence of magnification on digitizing to Precision of computerized measurement of coronary vessel diameter, the two measurement methods, i.e., a combined filter and Entropy filter, were applied to magnified images (x1-x6) of cineangiograms radiographed for a 3-mm vessel phantom. In conclusion, the desirable precision in clinical use, we thought, was obtainable at the magnification of x3 to x4. (author)

  18. Does Physical Fitness Buffer the Relationship between Psychosocial Stress, Retinal Vessel Diameters, and Blood Pressure among Primary Schoolchildren?

    Science.gov (United States)

    Gerber, Markus; Endes, Katharina; Herrmann, Christian; Colledge, Flora; Brand, Serge; Donath, Lars; Faude, Oliver; Pühse, Uwe; Hanssen, Henner; Zahner, Lukas

    2016-01-01

    Background . Strong evidence exists showing that psychosocial stress plays an important part in the development of cardiovascular diseases. Because physical inactivity is associated with less favourable retinal vessel diameter and blood pressure profiles, this study explores whether physical fitness is able to buffer the negative effects of psychosocial stress on retinal vessel diameters and blood pressure in young children. Methods . 325 primary schoolchildren (51% girls, M age = 7.28 years) took part in this cross-sectional research project. Retinal arteriolar diameters, retinal venular diameters, arteriolar to venular ratio, and systolic and diastolic blood pressure were assessed in all children. Interactions terms between physical fitness (performance in the 20 m shuttle run test) and four indicators of psychosocial stress (parental reports of critical life events, family, peer and school stress) were tested in a series of hierarchical regression analyses. Results . Critical life events and family, peer, and school-related stress were only weakly associated with retinal vessel diameters and blood pressure. No support was found for a stress-buffering effect of physical fitness. Conclusion . More research is needed with different age groups to find out if and from what age physical fitness can protect against arteriolar vessel narrowing and the occurrence of other cardiovascular disease risk factors.

  19. The relationship of retinal vessel diameters and fractal dimensions with blood pressure and cardiovascular risk factors.

    Directory of Open Access Journals (Sweden)

    Pengli Zhu

    Full Text Available BACKGROUND: This study aimed to investigate the correlation between quantitative retinal vascular parameters such as central retinal arteriolar equivalent (CRAE and retinal vascular fractal dimension (D(f, and cardiovascular risk factors in the Chinese Han population residing in the in islands of southeast China. METHODOLOGY/PRINCIPLE FINDINGS: In this cross-sectional study, fundus photographs were collected and semi-automated analysis software was used to analyze retinal vessel diameters and fractal dimensions. Cardiovascular risk factors such as relevant medical history, blood pressure (BP, lipids, and blood glucose data were collected. Subjects had a mean age of 51.9 ± 12.0 years and included 812 (37.4% males and 1,357 (62.6% females. Of the subjects, 726 (33.5% were overweight, 226 (10.4% were obese, 272 (12.5% had diabetes, 738 (34.0% had hypertension, and 1,156 (53.3% had metabolic syndrome. After controlling for the effects of potential confounders, multivariate analyses found that age (β = 0.06, P = 0.008, sex (β = 1.33, P = 0.015, mean arterial blood pressure (β = -0.12, P<0.001, high-sensitivity C-reactive protein (β = -0.22, P = 0.008, and CRVE (β = 0.23, P<0.001 were significantly associated with CRAE. Age (β = -0.0012, P < 0.001, BP classification (prehypertension: β = -0.0075, P = 0.014; hypertension: β = -0.0131, P = 0.002, and hypertension history (β = -0.0007, P = 0.009 were significantly associated with D(f. CONCLUSIONS/SIGNIFICANCE: D(f exhibits a stronger association with BP than CRAE. Thus, D(f may become a useful indicator of cardiovascular risk.

  20. Turbulent flow in a vessel agitated by side entering inclined blade turbine with different diameter using CFD simulation

    Science.gov (United States)

    Fathonah, N. N.; Nurtono, T.; Kusdianto; Winardi, S.

    2018-03-01

    Single phase turbulent flow in a vessel agitated by side entering inclined blade turbine has simulated using CFD. The aim of this work is to identify the hydrodynamic characteristics of a model vessel, which geometrical configuration is adopted at industrial scale. The laboratory scale model vessel is a flat bottomed cylindrical tank agitated by side entering 4-blade inclined blade turbine with impeller rotational speed N=100-400 rpm. The effect of the impeller diameter on fluid flow pattern has been investigated. The fluid flow patterns in a vessel is essentially characterized by the phenomena of macro-instabilities, i.e. the flow patterns change with large scale in space and low frequency. The intensity of fluid flow in the tank increase with the increase of impeller rotational speed from 100, 200, 300, and 400 rpm. It was accompanied by shifting the position of the core of circulation flow away from impeller discharge stream and approached the front of the tank wall. The intensity of fluid flow in the vessel increase with the increase of the impeller diameter from d=3 cm to d=4 cm.

  1. Effects of pomegranate extract on blood flow and vessel diameter after high-intensity exercise in young, healthy adults.

    Science.gov (United States)

    Roelofs, Erica J; Smith-Ryan, Abbie E; Trexler, Eric T; Hirsch, Katie R; Mock, Meredith G

    2017-04-01

    The effects of pomegranate extract (PE) supplementation were evaluated on high-intensity exercise performance, blood flow, vessel diameter, oxygen saturation (SPO 2 ), heart rate (HR), and blood pressure (BP). In a randomized, crossover design, nineteen recreationally resistance-trained participants were randomly assigned to PE (1000 mg) or placebo (PL), which were consumed 30 min prior to a repeated sprint ability (RSA) test and repetitions to fatigue (RTF) on bench and leg press. The RSA consisted of ten six-second sprints on a friction-loaded cycle ergometer with 30 s recovery. Brachial artery blood flow and vessel diameter were assessed by ultrasound. Blood flow, vessel diameter, SPO 2 , HR, and BP were assessed at baseline, 30 min post ingestion, immediately post exercise (IPost), and 30 min post exercise (30minPost). With PE, blood flow significantly increased IPost RSA (mean difference = 18.49 mL min -1 ; P exercise performance enhancement from increased delivery of substrates and oxygen. The acute timing and capsule form of PE may be advantageous to athletic populations due to ergogenic effects, taste, and convenience.

  2. Inter-method agreement in retinal blood vessels diameter analysis between Dynamic Vessel Analyzer and optical coherence tomography.

    Science.gov (United States)

    Benatti, Lucia; Corvi, Federico; Tomasso, Livia; Mercuri, Stefano; Querques, Lea; Ricceri, Fulvio; Bandello, Francesco; Querques, Giuseppe

    2017-06-01

    To analyze the inter-methods agreement in arteriovenous ratio (AVR) evaluation between spectral-domain optical coherence tomography (SD-OCT) and Dynamic Vessel Analyzer (DVA). Healthy volunteers underwent DVA and SD-OCT examination. AVR was measured by SD-OCT using the four external lines of the optic nerve head-centered 7-line cube and by DVA using an automated AVR estimation. The mean AVR was calculated, twice, separately by two independent readers for each tool. Twenty-two eyes of 11 healthy subjects (five women and six men, mean age 35) were included. AVR analysis by DVA showed high inter-observer agreement between reader 1 and 2, and high intra-observer agreement for both reader 1 and reader 2. With regard to AVR analysis on SD-OCT, we found high inter-observer agreement between reader 1 and 2, and low intra-observer agreement for reader 2 but high intra-observer agreement for reader 1. Overall, the mean AVR measured on SD-OCT turned out to be significantly higher than mean AVR measured through DVA (reader 1, 0.9023 ± 0.06 vs 0.8036 ± 0.08; p DVA and SD-OCT). We found significant difference in the two noninvasive methods for AVR measurement, with a tendency for SD-OCT to overestimate retinal vascular caliber in comparison to DVA. This may be useful for achieving greater accuracy in the evaluation of retinal vessel in ocular as well as systemic diseases.

  3. The influence of the blood vessel diameter on the full scattering profile from cylindrical tissues: experimental evidence for the shielding effect.

    Science.gov (United States)

    Feder, Idit; Duadi, Hamootal; Dreifuss, Tamar; Fixler, Dror

    2016-10-01

    Optical methods for detecting physiological state based on light-tissue interaction are noninvasive, inexpensive, simplistic, and thus very useful. The blood vessels in human tissue are the main cause of light absorbing and scattering. Therefore, the effect of blood vessels on light-tissue interactions is essential for optically detecting physiological tissue state, such as oxygen saturation, blood perfusion and blood pressure. We have previously suggested a new theoretical and experimental method for measuring the full scattering profile, which is the angular distribution of light intensity, of cylindrical tissues. In this work we will present experimental measurements of the full scattering profile of heterogenic cylindrical phantoms that include blood vessels. We show, for the first time that the vessel diameter influences the full scattering profile, and found higher reflection intensity for larger vessel diameters accordance to the shielding effect. For an increase of 60% in the vessel diameter the light intensity in the full scattering profile above 90° is between 9% to 40% higher, depending on the angle. By these results we claim that during respiration, when the blood-vessel diameter changes, it is essential to consider the blood-vessel diameter distribution in order to determine the optical path in tissues. A CT scan of the measured silicon-based phantoms. The phantoms contain the same blood volume in different blood-vessel diameters. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Automated detection and classification of major retinal vessels for determination of diameter ratio of arteries and veins

    Science.gov (United States)

    Muramatsu, Chisako; Hatanaka, Yuji; Iwase, Tatsuhiko; Hara, Takeshi; Fujita, Hiroshi

    2010-03-01

    Abnormalities of retinal vasculatures can indicate health conditions in the body, such as the high blood pressure and diabetes. Providing automatically determined width ratio of arteries and veins (A/V ratio) on retinal fundus images may help physicians in the diagnosis of hypertensive retinopathy, which may cause blindness. The purpose of this study was to detect major retinal vessels and classify them into arteries and veins for the determination of A/V ratio. Images used in this study were obtained from DRIVE database, which consists of 20 cases each for training and testing vessel detection algorithms. Starting with the reference standard of vasculature segmentation provided in the database, major arteries and veins each in the upper and lower temporal regions were manually selected for establishing the gold standard. We applied the black top-hat transformation and double-ring filter to detect retinal blood vessels. From the extracted vessels, large vessels extending from the optic disc to temporal regions were selected as target vessels for calculation of A/V ratio. Image features were extracted from the vessel segments from quarter-disc to one disc diameter from the edge of optic discs. The target segments in the training cases were classified into arteries and veins by using the linear discriminant analysis, and the selected parameters were applied to those in the test cases. Out of 40 pairs, 30 pairs (75%) of arteries and veins in the 20 test cases were correctly classified. The result can be used for the automated calculation of A/V ratio.

  5. Remote ischemia affects the diameter of larger retinal vessels in normal persons

    DEFF Research Database (Denmark)

    El Dabagh, Yasmin Sanaya Hauge; Petersen, Line; Pedersen, Michael

    2017-01-01

    and flicker stimulation before, immediately after, and one hour after RIC induced by transient ischemia in the left arm. Results:The baseline diameter of retinal venules was reduced non-significantly immediately after (p = 0.07) and significantly one hour after RIC (p

  6. Retinal vessel diameters decrease with macular ganglion cell layer thickness in autosomal dominant optic atrophy and in healthy subjects

    DEFF Research Database (Denmark)

    Rönnbäck, Cecilia; Grønskov, Karen; Larsen, Michael

    2014-01-01

    diameters (central retinal artery equivalent, CRAE, and central retinal vein equivalent, CRVE). Statistical analysis was corrected for age, gender, spherical equivalent refraction, axial length and mean arterial blood pressure (MABP) in a mixed model analysis. RESULTS: Retinal arteries and veins were...... ganglion cell-inner plexiform layer (GC-IPL) thickness (p = 0.0017 and p = 0.0057, respectively). CONCLUSION: Narrow retinal arteries and veins were associated not only with the severity of ADOA but with ganglion cell volume in patients with ADOA and in healthy subjects. This suggests that narrow vessels...

  7. About a mechanism of the influence of shear stress for viscosity of the blood in vessels of small diameter

    Directory of Open Access Journals (Sweden)

    Лев Николаевич Катюхин

    2014-12-01

    Full Text Available It is proposed a physiological and experimentally confirmed explanation of Fåhraeus-Lindqvist-effect in capillaries using the profile analyses of osmotic deformability of red blood cells. It was shown the dose-dependent change of the erythrocytes deformability in the stage of isotropic spheres after forming artificial water pores (nystatin and occlusion (PbCl2 of available pores. The Sigma-effect reducing of hematocrit and viscosity in a shear flow of blood through the vessels of a small diameter was conditioned by the interchange of liquid phase between the erythrocyte and the plasma.

  8. Investigation of umbilical venous vessels anatomy and diameters as a guideline for catheter placement in newborns.

    Science.gov (United States)

    Eifinger, F; Fuchs, Z; Koerber, F; Persigehl, T; Scaal, M

    2018-03-01

    Umbilical cord catheters (UCC) are important for the primary care of critically ill newborns. To analyze anatomical variations of the umbilical vein (UV) and its further course, we performed abdominal spiral-CT examinations on stillborns. The aim of the study was to explore the high incidence of mal-positioned UCCs and to improve their positioning. Eighteen stillborns were investigated (29.2 weeks ± 6.7 weeks (IQR)). CTs were performed using either air or contrast medium injection into the UV. We measured the diameter at the narrowest points of (i) the umbilical vein, (ii) the segmental portal vein, (iii) the left portal vein, (iv) the umbilical recess, and (v) the ductus venosus. The branching angles between (a) the umbilical vein and intrahepatic veins and (b) the ductus venosus and umbilical recess were measured. The diameter of the UV increases from 3.4 to 11 mm (median [IQR]:4.6 mm [4.2-6.9]: r 2  = 0.64). The left portal vein has a larger diameter (3.6 mm [2.6-4.55]; r 2  = 0.43) than the left segmental portal vein (2.3 mm [1.8-2.75]; r 2  = 0.23). The diameter of the ductus venosus (2.5 mm [1.6-3.4]; r 2  = 0.59) is half that of the umbilical recess (5.1 mm [3.3-6.2]; r 2  = 0.43). The most obtuse angle is formed by the junction between the umbilical recess and ductus venosus (151° [133-159]; r 2  = 0.001). The branch angle from the outgoing UV into the left portal vein is more obtuse (128° [123-144]; r 2  = 0.0001) than that of the segmental portal vein (115° [105-119]; r 2  = 0.0001). To avoid mal-positioning, our data suggest the use of a soft catheter. The UV and its extensions are wide enough to admit a 4 Fr. catheter without complete obstruction. Clin. Anat. 31:269-274, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  9. Carotid Atherosclerosis, Cerebrospinal Fluid Pressure, and Retinal Vessel Diameters: The Asymptomatic Polyvascular Abnormalities in Community Study.

    Directory of Open Access Journals (Sweden)

    Jing Yan Yang

    Full Text Available To assess relationships between carotid artery atherosclerosis and retinal arteriolar and venular diameters.The community-based longitudinal Asymptomatic Polyvascular Abnormalities Community Study (APAC included a sub-population of the Kailuan study which consisted of 101,510 employees and retirees of a coal mining industry. Based on the Chinese National Census 2010 and excluding individuals with history of cerebrovascular ischemic events, 4004 individuals were included into the APAC. All participants underwent a detailed clinical examination including blood laboratory tests and carotid artery duplex ultrasound examination. The cerebrospinal fluid pressure (CSFP was estimated using the formula: CSFP[mmHg] = 0.44xBody Mass Index[kg/m2]+0.16xDiastolic Blood Pressure[mmHg]-0.18 x Age[Years]-1.91.In multivariable analysis (goodness of fit r2:0.12, thicker retinal arteries were associated with a thinner common carotid artery intima-media thickness (IMT (P = 0.002; standardized regression coefficient beta:-0.06; non-standardized regression coefficient B:-6.92;95% confidence interval (CI:-11.2,-2.61 after adjusting for thicker retinal nerve fiber layer (P<0.001;beta:0.18;B:0.35;95%CI:0.28,0.42, lower diastolic blood pressure (P<0.001;beta:-0.16;B:-0.17;95%CI:-0.21,-0.3, younger age (P<0.001;beta:-0.08; B:-0.16;95%;CI:-0.25,-0.08, and less abdominal circumference (P = 0.003;beta:-0.06;B:-0.11;95%CI:-0.18,-0.03. Thicker retinal vein diameter was associated (r = 0.40 with higher estimated CSFP (P<0.001;beta:0.09;B:0.78;95%CI:0.47,1.08 after adjusting for wider retinal arteries (P<0.001;beta:0.27;B:0.36;95%CI:0.31,0.41, thicker retinal nerve fiber layer thickness (P = 0.03;beta:0.22;B:0.56;95%CI:0.46,0.65 and male gender (P<0.001;beta:-0.08;B:-3.98;95%CI:-5.88,2.09.Thinner retinal artery diameter was significantly, however weakly, associated with increased common carotid artery IMT. It suggests that retinal microvascular changes were only week indicators

  10. Automatic Segmentation of Vessels in In-Vivo Ultrasound Scans

    DEFF Research Database (Denmark)

    Tamimi-Sarnikowski, Philip; Brink-Kjær, Andreas; Moshavegh, Ramin

    2017-01-01

    was evaluated empirically and applied to a dataset of in-vivo 1770 images recorded from 8 healthy subjects. The segmentation results were compared to manual delineation performed by two experienced users. The results showed a sensitivity and specificity of 90.41 ± 11.2 % and 97.93 ± 5.7 % (mean ± standard......Ultrasound has become highly popular to monitor atherosclerosis, by scanning the carotid artery. The screening involves measuring the thickness of the vessel wall and diameter of the lumen. An automatic segmentation of the vessel lumen, can enable the determination of lumen diameter. This paper...... presents a fully automatic segmentation algorithm, for robustly segmenting the vessel lumen in longitudinal B-mode ultrasound images. The automatic segmentation is performed using a combination of B-mode and power Doppler images. The proposed algorithm includes a series of preprocessing steps, and performs...

  11. Porous hybrid structures based on P(DLLA-co-TMC) and collagen for tissue engineering of small-diameter blood vessels

    NARCIS (Netherlands)

    Buttafoco, L.; Boks, Niels P.; Engbers-Buijtenhuijs, P.; Grijpma, Dirk W.; Poot, Andreas A.; Dijkstra, Pieter J.; Vermes, I.; Feijen, Jan

    2006-01-01

    Poly (D,L-lactide)-7co-(1,3-trimethylene carbonate) [P(DLLA-co-TMC)] (83 mol % DLLA) was used to produce matrices suitable for tissue engineering of small-diameter blood vessels. The copolymer was processed into tubular structures with a porosity of 98% by melt spinning and fiber winding, thus

  12. Comparison between MDCT and Grayscale IVUS in a Quantitative Analysis of Coronary Lumen in Segments with or without Atherosclerotic Plaques

    Energy Technology Data Exchange (ETDEWEB)

    Falcão, João L. A. A.; Falcão, Breno A. A. [Heart Institute (InCor), University of São Paulo Medical School (USP), São Paulo, SP (Brazil); Gurudevan, Swaminatha V. [Cedars-Sinai Heart Institute, Los Angeles, California, USA (United States); Campos, Carlos M.; Silva, Expedito R.; Kalil-Filho, Roberto; Rochitte, Carlos E.; Shiozaki, Afonso A.; Coelho-Filho, Otavio R.; Lemos, Pedro A. [Heart Institute (InCor), University of São Paulo Medical School (USP), São Paulo, SP (Brazil)

    2015-04-15

    The diagnostic accuracy of 64-slice MDCT in comparison with IVUS has been poorly described and is mainly restricted to reports analyzing segments with documented atherosclerotic plaques. We compared 64-slice multidetector computed tomography (MDCT) with gray scale intravascular ultrasound (IVUS) for the evaluation of coronary lumen dimensions in the context of a comprehensive analysis, including segments with absent or mild disease. The 64-slice MDCT was performed within 72 h before the IVUS imaging, which was obtained for at least one coronary, regardless of the presence of luminal stenosis at angiography. A total of 21 patients were included, with 70 imaged vessels (total length 114.6 ± 38.3 mm per patient). A coronary plaque was diagnosed in segments with plaque burden > 40%. At patient, vessel, and segment levels, average lumen area, minimal lumen area, and minimal lumen diameter were highly correlated between IVUS and 64-slice MDCT (p < 0.01). However, 64-slice MDCT tended to underestimate the lumen size with a relatively wide dispersion of the differences. The comparison between 64-slice MDCT and IVUS lumen measurements was not substantially affected by the presence or absence of an underlying plaque. In addition, 64-slice MDCT showed good global accuracy for the detection of IVUS parameters associated with flow-limiting lesions. In a comprehensive, multi-territory, and whole-artery analysis, the assessment of coronary lumen by 64-slice MDCT compared with coronary IVUS showed a good overall diagnostic ability, regardless of the presence or absence of underlying atherosclerotic plaques.

  13. Relationship between vessel diameter and depth measurements within the limbus using ultra-high resolution optical coherence tomography

    Directory of Open Access Journals (Sweden)

    Emmanuel Alabi

    2018-01-01

    Conclusion: This study demonstrated that the UHR-OCT was capable of imaging morphometric characteristics such as the size and depth of vessels in the limbus. The results of this study suggest a difference in the size and depth of vessels across different positions of the limbus, which may be indicative of adaptations to chronic hypoxia caused by the covering of the superior limbus by the upper eyelid. UHR-OCT may be a useful tool to evaluate the effect of contact lenses on the microvascular properties within the limbus.

  14. The Time Course of Changes in Retinal Vessel Diameter in Response to Differing Durations of Flicker Light Provocation.

    Science.gov (United States)

    Heitmar, Rebekka; Summers, Robert J

    2015-11-01

    To determine the response of retinal vessels to differing durations of flicker light (FL) stimulation. We recorded retinal arterial and venous vessel dilation to 12.5 Hz FL provocation of varying duration (5, 7, 10, and 20 seconds) in 12 healthy young individuals (age range, 26-45 years). All participants underwent a full ocular examination including IOP and blood pressure measurements. Maximum dilation (MD) did not show a significant dependence on flicker duration in arteries, whereas maximum constriction (MC) did. In veins, however, MD significantly increased with flicker duration. Approximately 80% to 90% of MD in arteries is reached within 10 seconds of FL stimulation. The vast majority of arterial dilatory capacity is reached within 10 seconds of FL stimulation even though venous dilation continues strongly. Since MC of arteries shows a significant dependence on flicker duration, measurements at two different durations can provide more information about the retinal vascular system than at a single flicker duration alone.

  15. Cerebro-afferent vessel and pupillary basal diameter variation induced by stomatognathic trigeminal proprioception: a case report.

    Science.gov (United States)

    De Cicco, Vincenzo

    2012-09-03

    A patient affected by asymmetric hemodynamics of cerebro-afferent vessels underwent duplex color scanner investigations in occlusal proprioceptive un- and rebalance conditions. Pupillometric video-oculographic examinations were performed in order to spot connected trigeminal proprioceptive motor patterns able to interfere on sympathetic autonomic activity. The aim of this case report is to verify if involuntary jaw closing during swallowing, executed in unbalance and rebalance myoelectric activity, would be able to modify cerebral hemodynamics. A 56-year-old Caucasian Italian woman affected by asymmetric blood flow of cerebro-afferent vessels underwent an electromyographic investigation of her occlusal muscles in order to assess their occlusal functional balance. The extreme asymmetry of myoelectric activity in dental occlusion evidenced by electromyographic values suggested the rebalancing of the functions of occlusal muscles through concurrent transcutaneous stimulation of the trigeminal nerve supra- and submandibular motor branches. The above-mentioned method allowed the detection of a symmetric craniomandibular muscular relation that can be kept constant through the use of a cusp bite modeled on the inferior dental arch: called orthotic-syntropic bite for its peculiar use of electrostimulation. A few days later, the patient underwent a duplex color scanner investigation and pupillometric video-oculographic examinations in occlusal unbalance and rebalance conditions. A comparative data analysis showed that an unbalanced dental occlusal function may represent an interferential pattern on cerebral hemodynamics velocity and pupillometric evaluations have proved useful both in the analysis of locus coeruleus functional modalities and as a diagnostic tool in the assessment of pathologies involving locus coeruleus and autonomic systems. The inclusion of myoelectric masseter examinations can be useful in patients with asymmetric hemodynamics of cerebro

  16. Optimization of microCT imaging and blood vessel diameter quantitation of preclinical specimen vasculature with radiopaque polymer injection medium.

    Directory of Open Access Journals (Sweden)

    Sergio X Vasquez

    2011-04-01

    Full Text Available Vascular networks within a living organism are complex, multi-dimensional, and challenging to image capture. Radio-angiographic studies in live animals require a high level of infrastructure and technical investment in order to administer costly perfusion mediums whose signals metabolize and degrade relatively rapidly, diminishing within a few hours or days. Additionally, live animal specimens must not be subject to long duration scans, which can cause high levels of radiation exposure to the specimen, limiting the quality of images that can be captured. Lastly, despite technological advances in live-animal specimen imaging, it is quite difficult to minimize or prevent movement of a live animal, which can cause motion artifacts in the final data output. It is demonstrated here that through the use of postmortem perfusion protocols of radiopaque silicone polymer mediums and ex-vivo organ harvest, it is possible to acquire a high level of vascular signal in preclinical specimens through the use of micro-computed tomographic (microCT imaging. Additionally, utilizing high-order rendering algorithms, it is possible to further derive vessel morphometrics for qualitative and quantitative analysis.

  17. Network of endocardial vessels.

    Science.gov (United States)

    Lee, Byung-Cheon; Kim, Hong Bae; Sung, Baeckkyoung; Kim, Ki Woo; Sohn, Jamin; Son, Boram; Chang, Byung-Joon; Soh, Kwang-Sup

    2011-01-01

    Although there have been reports on threadlike structures inside the heart, they have received little attention. We aimed to develop a method for observing such structures and to reveal their ultrastructures. An in situ staining method, which uses a series of procedures of 0.2-0.4% trypan blue spraying and washing, was applied to observe threadlike structures on the surfaces of endocardia. The threadlike structures were isolated and observed by using confocal laser scanning microscopy (CLSM) and transmission electron microscopy (TEM). Networks of endocardial vessels (20 μm in thickness) with expansions (40-100 μm in diameter) were visualized; they were movable on the endocardium of the bovine atrium and ventricle. CLSM showed that (1) rod-shaped nuclei were aligned along the longitudinal direction of the endocardial vessel and (2) there were many cells inside the expansion. TEM on the endocardial vessel revealed that (1) there existed multiple lumens (1-7 μm in diameter) and (2) the extracellular matrices mostly consisted of collagen fibers, which were aligned along the longitudinal direction of the endocardial vessel or were locally organized in reticular structures. We investigated the endocardial circulatory system in bovine cardiac chambers and its ultrastructures, such as nucleic distributions, microlumens, and collagenous extracellular matrices. Copyright © 2011 S. Karger AG, Basel.

  18. Neurovascular Network Explorer 1.0: a database of 2-photon single-vessel diameter measurements with MATLAB® graphical user interface

    Directory of Open Access Journals (Sweden)

    Vishnu B Sridhar

    2014-05-01

    Full Text Available We present a database client software – Neurovascular Network Explorer 1.0 (NNE 1.0 – that uses MATLAB® based Graphical User Interface (GUI for interaction with a database of 2-photon single-vessel diameter measurements from our previous publication [1]. These data are of particular interest for modeling the hemodynamic response. NNE 1.0 is downloaded by the user and then runs either as a MATLAB script or as a standalone program on a Windows platform. The GUI allows browsing the database according to parameters specified by the user, simple manipulation and visualization of the retrieved records (such as averaging and peak-normalization, and export of the results. Further, we provide NNE 1.0 source code. With this source code, the user can database their own experimental results, given the appropriate data structure and naming conventions, and thus share their data in a user-friendly format with other investigators. NNE 1.0 provides an example of seamless and low-cost solution for sharing of experimental data by a regular size neuroscience laboratory and may serve as a general template, facilitating dissemination of biological results and accelerating data-driven modeling approaches.

  19. Neurovascular Network Explorer 1.0: a database of 2-photon single-vessel diameter measurements with MATLAB(®) graphical user interface.

    Science.gov (United States)

    Sridhar, Vishnu B; Tian, Peifang; Dale, Anders M; Devor, Anna; Saisan, Payam A

    2014-01-01

    We present a database client software-Neurovascular Network Explorer 1.0 (NNE 1.0)-that uses MATLAB(®) based Graphical User Interface (GUI) for interaction with a database of 2-photon single-vessel diameter measurements from our previous publication (Tian et al., 2010). These data are of particular interest for modeling the hemodynamic response. NNE 1.0 is downloaded by the user and then runs either as a MATLAB script or as a standalone program on a Windows platform. The GUI allows browsing the database according to parameters specified by the user, simple manipulation and visualization of the retrieved records (such as averaging and peak-normalization), and export of the results. Further, we provide NNE 1.0 source code. With this source code, the user can database their own experimental results, given the appropriate data structure and naming conventions, and thus share their data in a user-friendly format with other investigators. NNE 1.0 provides an example of seamless and low-cost solution for sharing of experimental data by a regular size neuroscience laboratory and may serve as a general template, facilitating dissemination of biological results and accelerating data-driven modeling approaches.

  20. Neurovascular Network Explorer 1.0: a database of 2-photon single-vessel diameter measurements with MATLAB® graphical user interface

    Science.gov (United States)

    Sridhar, Vishnu B.; Tian, Peifang; Dale, Anders M.; Devor, Anna; Saisan, Payam A.

    2014-01-01

    We present a database client software—Neurovascular Network Explorer 1.0 (NNE 1.0)—that uses MATLAB® based Graphical User Interface (GUI) for interaction with a database of 2-photon single-vessel diameter measurements from our previous publication (Tian et al., 2010). These data are of particular interest for modeling the hemodynamic response. NNE 1.0 is downloaded by the user and then runs either as a MATLAB script or as a standalone program on a Windows platform. The GUI allows browsing the database according to parameters specified by the user, simple manipulation and visualization of the retrieved records (such as averaging and peak-normalization), and export of the results. Further, we provide NNE 1.0 source code. With this source code, the user can database their own experimental results, given the appropriate data structure and naming conventions, and thus share their data in a user-friendly format with other investigators. NNE 1.0 provides an example of seamless and low-cost solution for sharing of experimental data by a regular size neuroscience laboratory and may serve as a general template, facilitating dissemination of biological results and accelerating data-driven modeling approaches. PMID:24904401

  1. Laser photothermolysis of single blood vessels in the chick chorioallantoic membrane (CAM)

    Science.gov (United States)

    Kimel, Sol; Svaasand, Lars O.; Milner, Thomas E.; Hammer-Wilson, Marie J.; Schell, Michael J.; Nelson, J. Stuart; Berns, Michael W.

    1994-02-01

    Individual blood vessels in the chick chorioallantoic membrane (CAM) were selectively coagulated through photothermolysis, using pulsed laser irradiation at 585 nm. Pulse durations were chosen to be 0.45 ms and 10 ms, which correspond to the thermal relaxation times in blood vessels of 30 micrometers and 150 micrometers diameter, respectively. The dose vs diameter (D vs d) relationship for coagulation was calculated for the two pulse shapes. The energy deposited in a cylindrical absorber of diameter d by an optical field, incident perpendicular to the vessel, was expressed analytically and compared with the energy required to coagulate a blood vessel of the same lumen diameter. When thermal diffusion is incorporated into the model, our findings can be accounted for quantitatively. This information will be of use for improving the laser treatment of port wine stains and other vasculopathies.

  2. Retrospective analysis of the effect of aflibercept loading dose on the retinal vessel diameters in patients with treatment-naive neovascular AMD.

    Science.gov (United States)

    Tetikoğlu, Mehmet; Kurt, Muhammed Mustafa; Sağdık, Hacı Murat; Aktaş, Serdar; Yıldırım, Medine Aslı; Özcura, Fatih

    2018-03-01

    To evaluate the effects of intravitreal aflibercept (IVA) on retinal vessel diameters in patients with neovascular age-related macular degeneration (AMD). A retrospective study conducted at the Kutahya Dumlupinar University Faculty of Medicine included 15 eyes of 15 patients with treatment naive neovascular AMD. All eyes received IVA injections once per month for 3 months; untreated contralateral eyes were used as controls. The central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and artery-vein ratio (AVR) values were measured using a computer-based program before the first IVA injection and 30 days after the first, second, and third injections. The main outcome measurements were the central macular thickness (CMT), best-corrected visual acuity (BCVA), choroidal thickness, CRAE, CRVE, and AVR. Significant vasoconstriction of the retinal arterioles was observed in all eyes treated with IVA when compared to baseline (p = 0.009). However, no significant differences were found for CRVE or AVR throughout the study period in treated eyes. In the control group, all parameters measured during each visit were similar to baseline measurements (p > 0.05). The mean BCVA significantly improved at the end of the loading dose of IVA, when compared to baseline (p = 0.006). After the IVA injections, the mean CMT and choroidal thickness were significantly reduced at all visits, compared to baseline (p < 0.001). The current study showed that IVA led to significant retinal arteriolar vasoconstriction and choroidal thinning, which may cause reduced retinal blood flow.

  3. Thoracic Endovascular Aortic Repair into the False Lumen in Chronic Aortic Dissection.

    Science.gov (United States)

    Kamman, Arnoud V; Williams, David M; Patel, Himanshu J

    2017-07-01

    Deployment of a stent graft for the treatment of aortic dissections is normally performed in the true lumen. However, in some rare occasions landing in the false lumen may be appropriate. We present 2 different cases of chronic aortic dissection, where we opted to land the stent graft into the false lumen to treat the associated aneurysm. For the first case, the goal of thoracic endovascular aortic repair (TEVAR) was to exclude the aneurysm from within the false lumen because of a slit-like true lumen. In the second case, the visceral arteries came off the false lumen, with the renal vessels from the true lumen. False lumen TEVAR was performed, and the infrarenal aorta fenestrated, as to ensure adequate perfusion. These different clinical scenarios show how false lumen TEVAR for chronic dissections with associated aneurysms can be an alternative treatment approach and highlight the importance of assessing the origin of branch vessels and the possible necessity of reperfusion of these, before TEVAR is performed. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Evaluation of an improved technique for automated center lumen line definition in cardiovascular image data

    International Nuclear Information System (INIS)

    Gratama van Andel, Hugo A.F.; Meijering, Erik; Vrooman, Henri A.; Stokking, Rik; Lugt, Aad van der; Monye, Cecile de

    2006-01-01

    The aim of the study was to evaluate a new method for automated definition of a center lumen line in vessels in cardiovascular image data. This method, called VAMPIRE, is based on improved detection of vessel-like structures. A multiobserver evaluation study was conducted involving 40 tracings in clinical CTA data of carotid arteries to compare VAMPIRE with an established technique. This comparison showed that VAMPIRE yields considerably more successful tracings and improved handling of stenosis, calcifications, multiple vessels, and nearby bone structures. We conclude that VAMPIRE is highly suitable for automated definition of center lumen lines in vessels in cardiovascular image data. (orig.)

  5. Lumen segmentation in magnetic resonance images of the carotid artery.

    Science.gov (United States)

    Jodas, Danilo Samuel; Pereira, Aledir Silveira; R S Tavares, João Manuel

    2016-12-01

    Investigation of the carotid artery plays an important role in the diagnosis of cerebrovascular events. Segmentation of the lumen and vessel wall in Magnetic Resonance (MR) images is the first step towards evaluating any possible cardiovascular diseases like atherosclerosis. However, the automatic segmentation of the lumen is still a challenge due to the low quality of the images and the presence of other elements such as stenosis and malformations that compromise the accuracy of the results. In this article, a method to identify the location of the lumen without user interaction is presented. The proposed method uses the modified mean roundness to calculate the circularity index of the regions identified by the K-means algorithm and return the one with the maximum value, i.e. the potential lumen region. Then, an active contour is employed to refine the boundary of this region. The method achieved an average Dice coefficient of 0.78±0.14 and 0.61±0.21 in 181 3D-T1-weighted and 181 proton density-weighted MR images, respectively. The results show that this method is promising for the correct identification and location of the lumen even in images corrupted by noise. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Regional blood flow analysis and its relationship with arterial branch lengths and lumen volume in the coronary arterial tree

    International Nuclear Information System (INIS)

    Molloi, Sabee; Wong, Jerry T

    2007-01-01

    The limitations of visually assessing coronary artery disease are well known. These limitations are particularly important in intermediate coronary lesions (30-70% diameter stenosis) where it is difficult to determine whether a particular lesion is the cause of ischaemia. Therefore, a functional measure of stenosis severity is needed. The purpose of this study is to determine whether the expected maximum coronary blood flow in an arterial tree is predictable from its sum of arterial branch lengths or lumen volume. Using a computer model of a porcine coronary artery tree, an analysis of blood flow distribution was conducted through a network of millions of vessels that included the entire coronary artery tree down to the first capillary branch. The flow simulation results show that there is a linear relationship between coronary blood flow and the sum of its arterial branch lengths. This relationship holds over the entire arterial tree. The flow simulation results also indicate that there is a 3/4 er relation between coronary blood flow (Q) and the sum of its arterial lumen volume (V). Moreover, there is a linear relationship between normalized Q and normalized V raised to a power of 3/4 over the entire arterial tree. These results indicate that measured arterial branch lengths or lumen volumes can be used to predict the expected maximum blood flow in an arterial tree. This theoretical maximum blood flow, in conjunction with an angiographically measured blood flow, can potentially be used to calculate fractional flow reserve based entirely on angiographic data

  7. Imaging of pediatric great vessel stents: Computed tomography or magnetic resonance imaging?

    Directory of Open Access Journals (Sweden)

    A M den Harder

    Full Text Available Complications might occur after great vessel stent implantation in children. Therefore follow-up using imaging is warranted.To determine the optimal imaging modality for the assessment of stents used to treat great vessel obstructions in children.Five different large vessel stents were evaluated in an in-vitro setting. All stents were expanded to the maximal vendor recommended diameter (20mm; n = 4 or 10mm; n = 1, placed in an anthropomorphic chest phantom and imaged with a 256-slice CT-scanner. MRI images were acquired at 1.5T using a multi-slice T2-weighted turbo spin echo, an RF-spoiled three-dimensional T1-weighted Fast Field Echo and a balanced turbo field echo 3D sequence. Two blinded observers assessed stent lumen visibility (measured diameter/true diameter *100% in the center and at the outlets of the stent. Reproducibility of diameter measurements was evaluated using the intraclass correlation coefficient for reliability and 95% limits of agreement for agreement analysis.Median stent lumen visibility was 88 (IQR 86-90% with CT for all stents at both the center and outlets. With MRI, the T2-weighted turbo spin echo sequence was preferred which resulted in 82 (78-84% stent lumen visibility. Interobserver reliability and agreement was good for both CT (ICC 0.997, mean difference -0.51 [-1.07-0.05] mm and MRI measurements (ICC 0.951, mean difference -0.05 [-2.52 --2.41] mm.Good in-stent lumen visibility was achievable in this in-vitro study with both CT and MRI in different great vessel stents. Overall reliability was good with clinical acceptable limits of agreement for both CT and MRI. However, common conditions such as in-stent stenosis and associated aneurysms were not tested in this in-vitro study, limiting the value of the in-vitro study.

  8. A distinct mechanism of vascular lumen formation in Xenopus requires EGFL7.

    Directory of Open Access Journals (Sweden)

    Marta S Charpentier

    Full Text Available During vertebrate blood vessel development, lumen formation is the critical process by which cords of endothelial cells transition into functional tubular vessels. Here, we use Xenopus embryos to explore the cellular and molecular mechanisms underlying lumen formation of the dorsal aorta and the posterior cardinal veins, the primary major vessels that arise via vasculogenesis within the first 48 hours of life. We demonstrate that endothelial cells are initially found in close association with one another through the formation of tight junctions expressing ZO-1. The emergence of vascular lumens is characterized by elongation of endothelial cell shape, reorganization of junctions away from the cord center to the periphery of the vessel, and onset of Claudin-5 expression within tight junctions. Furthermore, unlike most vertebrate vessels that exhibit specialized apical and basal domains, we show that early Xenopus vessels are not polarized. Moreover, we demonstrate that in embryos depleted of the extracellular matrix factor Epidermal Growth Factor-Like Domain 7 (EGFL7, an evolutionarily conserved factor associated with vertebrate vessel development, vascular lumens fail to form. While Claudin-5 localizes to endothelial tight junctions of EGFL7-depleted embryos in a timely manner, endothelial cells of the aorta and veins fail to undergo appropriate cell shape changes or clear junctions from the cell-cell contact. Taken together, we demonstrate for the first time the mechanisms by which lumens are generated within the major vessels in Xenopus and implicate EGFL7 in modulating cell shape and cell-cell junctions to drive proper lumen morphogenesis.

  9. In 6- to 8-year-old children, hair cortisol is associated with body mass index and somatic complaints, but not with stress, health-related quality of life, blood pressure, retinal vessel diameters, and cardiorespiratory fitness.

    Science.gov (United States)

    Gerber, Markus; Endes, Katharina; Brand, Serge; Herrmann, Christian; Colledge, Flora; Donath, Lars; Faude, Oliver; Pühse, Uwe; Hanssen, Henner; Zahner, Lukas

    2017-02-01

    Hair cortisol measurement has become an increasingly accepted approach in endocrinology and biopsychology. However, while in adult research hair cortisol has been proposed as a relevant biomarker for chronic stress (and its adverse consequences), studies with children are scarce. Therefore, the goal of the present exploratory study was to examine the associations between hair cortisol concentrations (HCCs), stress, and a series of health-related outcomes in a sample of Swiss first grade schoolchildren. The sample consisted of 318 children (53% girls, M age =7.26, SD=0.35). Hair strands were taken near the scalp from a posterior vertex position, and HCCs were tested for the first 3-cm hair segment. Parents provided information about their children's age, gender, parental education, children's stress (recent critical life events, daily hassles), health-related quality of life, and psychosomatic complaints. Body composition, blood pressure, retinal vessel diameters, and cardiorespiratory fitness were measured with established methods. In multiple regression analyses, higher HCCs were weakly associated with increased BMI in girls (β=0.22, phealth-related quality of life, blood pressure, retinal vessel diameters, and cardiorespiratory fitness. Although small significant relationships were found between HCCs, BMI and somatic complaints, the findings of this exploratory study challenge the view that HCCs can be used as a reliable biomarker of recent critical life events, daily hassles, health-related quality of life, and cardiovascular health indicators in non-clinical young children. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Influence of Root Diameter and Soil Depth on the Xylem Anatomy of Fine- to Medium-Sized Roots of Mature Beech Trees in the Top- and Subsoil.

    Science.gov (United States)

    Kirfel, Kristina; Leuschner, Christoph; Hertel, Dietrich; Schuldt, Bernhard

    2017-01-01

    Despite their importance for water uptake and transport, the xylem anatomical and hydraulic properties of tree roots have only rarely been studied in the field. We measured mean vessel diameter ( D ), vessel density (VD), relative vessel lumen area (lumen area per xylem area) and derived potential hydraulic conductivity ( K p ) in the xylem of 197 fine- to medium-diameter roots (1-10 mm) in the topsoil and subsoil (0-200 cm) of a mature European beech forest on sandy soil for examining the influence of root diameter and soil depth on xylem anatomical and derived hydraulic traits. All anatomical and functional traits showed strong dependence on root diameter and thus root age but no significant relation to soil depth. Averaged over topsoil and deep soil and variable flow path lengths in the roots, D increased linearly with root diameter from ∼50 μm in the smallest diameter class (1-2 mm) to ∼70 μm in 6-7 mm roots (corresponding to a mean root age of ∼12 years), but remained invariant in roots >7 mm. D never exceeded ∼82 μm in the 1-10 mm roots, probably in order to control the risk of frost- or drought-induced cavitation. This pattern was overlain by a high variability in xylem anatomy among similar-sized roots with K p showing a higher variance component within than between root diameter classes. With 8% of the roots exceeding average K p in their diameter class by 50-700%, we obtained evidence of the existence of 'high-conductivity roots' indicating functional differentiation among similar-sized roots. We conclude that the hydraulic properties of small to medium diameter roots of beech are mainly determined by root age, rendering root diameter a suitable predictor of hydraulic functioning, while soil depth - without referring to path length - had a negligible effect.

  11. Influence of Root Diameter and Soil Depth on the Xylem Anatomy of Fine- to Medium-Sized Roots of Mature Beech Trees in the Top- and Subsoil

    Directory of Open Access Journals (Sweden)

    Kristina Kirfel

    2017-07-01

    Full Text Available Despite their importance for water uptake and transport, the xylem anatomical and hydraulic properties of tree roots have only rarely been studied in the field. We measured mean vessel diameter (D, vessel density (VD, relative vessel lumen area (lumen area per xylem area and derived potential hydraulic conductivity (Kp in the xylem of 197 fine- to medium-diameter roots (1–10 mm in the topsoil and subsoil (0–200 cm of a mature European beech forest on sandy soil for examining the influence of root diameter and soil depth on xylem anatomical and derived hydraulic traits. All anatomical and functional traits showed strong dependence on root diameter and thus root age but no significant relation to soil depth. Averaged over topsoil and deep soil and variable flow path lengths in the roots, D increased linearly with root diameter from ∼50 μm in the smallest diameter class (1–2 mm to ∼70 μm in 6–7 mm roots (corresponding to a mean root age of ∼12 years, but remained invariant in roots >7 mm. D never exceeded ∼82 μm in the 1–10 mm roots, probably in order to control the risk of frost- or drought-induced cavitation. This pattern was overlain by a high variability in xylem anatomy among similar-sized roots with Kp showing a higher variance component within than between root diameter classes. With 8% of the roots exceeding average Kp in their diameter class by 50–700%, we obtained evidence of the existence of ‘high-conductivity roots’ indicating functional differentiation among similar-sized roots. We conclude that the hydraulic properties of small to medium diameter roots of beech are mainly determined by root age, rendering root diameter a suitable predictor of hydraulic functioning, while soil depth – without referring to path length – had a negligible effect.

  12. Performance improvements of the BNC tubes from unique double-silicone-tube bioreactors by introducing chitosan and heparin for application as small-diameter artificial blood vessels.

    Science.gov (United States)

    Li, Xue; Tang, Jingyu; Bao, Luhan; Chen, Lin; Hong, Feng F

    2017-12-15

    In order to improve property of bacterial nano-cellulose (BNC) to achieve the requirements of clinical application as small caliber vascular grafts, chitosan (CH) was deposited into the fibril network of the BNC tubes fabricated in unique Double-Silicone-Tube bioreactors. Heparin (Hep) was then chemically grafted into the BNC-based tubes using EDC/NHS crosslinking to improve performance of anticoagulation and endothelialization. Physicochemical and mechanical property, blood compatibility, and cytocompatibility were compared before and after compositing. The results indicated that strength at break was increased but burst pressure decreased slightly after compositing. Performance of the BNC tubes was improved remarkably after introducing chitosan and heparin. The EDC/NHS crosslinking catalyzed both amide bonds and ester bonds formation in the BNC/CH-Hep composites. Three-dimensional surface structure and roughness were firstly obtained and discussed in relation to the hemocompatibility of BNC-based tubes. This work demonstrates the heparinized BNC-based tubes have great potential in application as small-diameter vascular prosthesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Histomorphometric study of lumen of human vermiform appendix.

    Science.gov (United States)

    Rahman, M M; Khalil, M; Sultana, S Z; Jahan, M K; Shafiquzzaman, M; Parvin, B; Islam, M T

    2012-01-01

    This study was done to find out the histomorphometry of lumen of vermiform appendix in Bangladeshi people. Total 100 fresh appendixes were collected for morphometric study of different age and sex during postmortem examination in the autopsy laboratory of Forensic Medicine Department of Mymensingh Medical College. This cross sectional descriptive study was done by convenient sampling technique. For convenience of differentiating the luminal diameter of vermiform appendix in relation to age and sex, findings were classified in four groups. Group A was up to 20 years, Group B 21-35 years, Group C 36-55 years and Group D 56-70 years. In the study the maximum diameter was in group A of female (87.00 μm) and minimum was (4.70 μm) in group B of female. The mean luminal diameter of vermiform appendix was more in female (60.71 μm) than in male (60.11 μm).

  14. High-salt diet increases hormonal sensitivity in skin pre-capillary resistance vessels.

    Science.gov (United States)

    Helle, F; Karlsen, T V; Tenstad, O; Titze, J; Wiig, H

    2013-03-01

    Recent data indicate that the skin of rats on a high-salt diet is able to accumulate Na(+) without commensurate water. This extrarenal mechanism of Na(+) homoeostasis could affect skin vasoregulation. We hypothesized that the major resistance vessel of rat skin, the pre-capillary arterioles, has increased vasoreactivity within the physiological range of circulating ANG II, a hormone relevant to salt-sensitive hypertension. Skin arterioles from skin and muscle were isolated using the agar-infusion technique. Vessels from rats fed high-salt and low-salt diet had similar lumen diameter and media area/lumen area ratio. Contractile sensitivity to ANG II was increased in skin vessels from high-salt vessels at all doses tested starting at 10(-10) m (P diet. As ANG II and the renin-angiotensin system are strongly involved in salt conservation, we explored whether vasoreactivity for noradrenaline was increased as well, because this is a functionally unrelated hormone. At low doses, contractions were similar, but at 10(-5) and 10(-4) m, noradrenaline produced stronger contractions in skin vessels from high-salt compared with low-salt rats (P high-salt diet, which could increase peripheral resistance in many situations and contribute to higher pressure in salt-sensitive hypertension. As vessels from adjacent muscle were unaffected, we raise the interesting possibility that increased vasoreactivity in the skin could be linked to osmotically inactive Na(+) accumulation. © 2012 The Authors Acta Physiologica © 2012 Scandinavian Physiological Society.

  15. Technical Note: Measurement of common carotid artery lumen dynamics using black-blood MR cine imaging.

    Science.gov (United States)

    Dai, Erpeng; Dong, Li; Zhang, Zhe; Li, Lyu; Zhang, Hui; Zhao, Xihai; Wang, Jinnan; Yuan, Chun; Guo, Hua

    2017-03-01

    To demonstrate the feasibility of measuring the common carotid artery (CCA) lumen dynamics using a black-blood cine (BB-cine) imaging method. Motion-sensitized driven-equilibrium (MSDE) prepared spoiled gradient sequence was used for the BB-cine imaging. CCAs of eleven healthy volunteers were studied using this method. Lumen dynamics, including lumen area evolution waveforms and distension values, were measured and evaluated by comparing this method with bright-blood cine (BrB-cine) imaging. Compared with the BrB-cine images, flow artifacts were effectively suppressed in the BB-cine images. BrB-cine images generally show larger lumen areas than BB-cine images. The lumen area waveforms and distension measurements from BB-cine imaging showed smaller variances among different subjects than BrB-cine imaging. The proposed BB-cine imaging technique can suppress the flow artifacts effectively and reduce the partial volume effects from the vessel wall. This might allow more accurate lumen dynamics measurements than traditional BrB-cine imaging, which may further be valuable for investigating biomechanical and functional properties of the cardiovascular system. © 2017 American Association of Physicists in Medicine.

  16. Effects of irradiation on renal vessels of rabbits

    International Nuclear Information System (INIS)

    Hanayama, Hirotaka

    1982-01-01

    The male rabbits weighing approximately 3 kg were divided into two groups: one group received irradiation to the left kidney through 6 x 4 cm field size with doses of 5 Gy, while the other group was irradiated with 50 Gy. The vessel casts were observed using the injection replica scanning electron microscopic method. In 50 Gy irradiated group, the surface of blood vessel's lumen became irregular with a decrease in the number of glomeruli at 5 days. Partial narrowing was also seen in the cortex and glomerular vessels. The number of glomeruli decreased by 48% one week later and 90% 4 weeks later. The cortex vessels progressively narrowed, and irregularity of the net-like structure was also observed. Similarly, a decrease in the number of glomeruli and partial narrowing of the blood vessels were seen at 5 days on the nonirradiated side, but the damage was considerably less than that on the irradiated side. In the 5 Gy irradiated group, a decrease in the number of glomeruli was seen 5 days later and it became 71% 5 days later and 81% one week later. It returned to 95% 4 weeks later. No changes whatsoever were seen in the non-irradiated side after 4 weeks and changes in the number of glomeruli were not observed. The vasculation of medulla showed no changes in the 50 Gy or the 5 Gy irradiated group. There were seen no significant changes in the blood vessel diameter. (J.P.N.)

  17. ARCOCT: Automatic detection of lumen border in intravascular OCT images.

    Science.gov (United States)

    Cheimariotis, Grigorios-Aris; Chatzizisis, Yiannis S; Koutkias, Vassilis G; Toutouzas, Konstantinos; Giannopoulos, Andreas; Riga, Maria; Chouvarda, Ioanna; Antoniadis, Antonios P; Doulaverakis, Charalambos; Tsamboulatidis, Ioannis; Kompatsiaris, Ioannis; Giannoglou, George D; Maglaveras, Nicos

    2017-11-01

    Intravascular optical coherence tomography (OCT) is an invaluable tool for the detection of pathological features on the arterial wall and the investigation of post-stenting complications. Computational lumen border detection in OCT images is highly advantageous, since it may support rapid morphometric analysis. However, automatic detection is very challenging, since OCT images typically include various artifacts that impact image clarity, including features such as side branches and intraluminal blood presence. This paper presents ARCOCT, a segmentation method for fully-automatic detection of lumen border in OCT images. ARCOCT relies on multiple, consecutive processing steps, accounting for image preparation, contour extraction and refinement. In particular, for contour extraction ARCOCT employs the transformation of OCT images based on physical characteristics such as reflectivity and absorption of the tissue and, for contour refinement, local regression using weighted linear least squares and a 2nd degree polynomial model is employed to achieve artifact and small-branch correction as well as smoothness of the artery mesh. Our major focus was to achieve accurate contour delineation in the various types of OCT images, i.e., even in challenging cases with branches and artifacts. ARCOCT has been assessed in a dataset of 1812 images (308 from stented and 1504 from native segments) obtained from 20 patients. ARCOCT was compared against ground-truth manual segmentation performed by experts on the basis of various geometric features (e.g. area, perimeter, radius, diameter, centroid, etc.) and closed contour matching indicators (the Dice index, the Hausdorff distance and the undirected average distance), using standard statistical analysis methods. The proposed method was proven very efficient and close to the ground-truth, exhibiting non statistically-significant differences for most of the examined metrics. ARCOCT allows accurate and fully-automated lumen border

  18. Extraluminal laser angioplasty (ELAN): a new method for treating atherosclerotic vessels

    Science.gov (United States)

    Will, Fabian; Singh, Ajoy I.; Ertmer, Wolfgang; Welling, Herbert; Lubatschowski, Holger

    2003-06-01

    ELAN is a new method for treating atherosclerotic vessels. Its purpose is to restore wall flexibility by removing arterial wall tissue from the outer arterial layer. This leads to expansion of the narrowed vessel resulting in increased blood flow. We generated cuts in dissected arteries of sheep and pigs by photo-ablation with an ArF-Excimer Laser operating at a wavelength of 193 nm. During the cutting process the vessel diameter was monitored by measuring the running time of the laser induced pressure transients with a pressure transducer lying under the artery. A nearly linear increase of the diameter dependent on the residual wall thickness was found with a maximum increase of vessel diameter about 10%. We also observed that the arterial wall maintains stable to very small residual wall thicknesses i.e. deep cutting. To support the experiments and to test different geometries of tissue removal we performed FEM-Analysis. We simulated vessel deformation and the total strain depending on the depth, width and number of cuts in the outer artieral wall. We also found a significant increase of the "lumen" in a model with atherosclerotic shape obtained from a histological section.

  19. FFTF and CRBRP reactor vessels

    International Nuclear Information System (INIS)

    Morgan, R.E.

    1977-01-01

    The Fast Flux Test Facility (FFTF) reactor vessel and the Clinch River Breeder Reactor Plant (CRBRP) reactor vessel each serve to enclose a fast spectrum reactor core, contain the sodium coolant, and provide support and positioning for the closure head and internal structure. Each vessel is located in its reactor cavity and is protected by a guard vessel which would ensure continued decay heat removal capability should a major system leak develop. Although the two plants have significantly different thermal power ratings, 400 megawatts for FFTF and 975 megawatts for CRBRP, the two reactor vessels are comparable in size, the CRBRP vessel being approximately 28% longer than the FFTF vessel. The FFTF vessel diameter was controlled by the space required for the three individual In-Vessel Handling Machines and Instrument Trees. Utilization of the triple rotating plug scheme for CRBRP refueling enables packaging of the larger CRBRP core in a vessel the same diameter as the FFTF vessel

  20. The requirement for fibroblasts in angiogenesis: fibroblast-derived matrix proteins are essential for endothelial cell lumen formation.

    Science.gov (United States)

    Newman, Andrew C; Nakatsu, Martin N; Chou, Wayne; Gershon, Paul D; Hughes, Christopher C W

    2011-10-01

    A role for fibroblasts in physiological and pathological angiogenesis is now well recognized; however, the precise mechanisms underlying their action have not been determined. Using an in vitro angiogenesis model in combination with a candidate gene approach, column chromatography, and mass spectrometry, we identify two classes of fibroblast-derived factors--one that supports vessel sprouting but not lumen formation, and one that promotes lumen formation. In the absence of fibroblasts a combination of angiopoietin-1, angiogenin, hepatocyte growth factor, transforming growth factor-α, and tumor necrosis factor drives robust endothelial cell (EC) sprouting; however, lumens fail to form. Subsequent addition of fibroblast-conditioned medium restores lumenogenesis. Using small interfering RNA-mediated knockdown, we show that five genes expressed in fibroblasts--collagen I, procollagen C endopeptidase enhancer 1, secreted protein acidic and rich in cysteine, transforming growth factor-β-induced protein ig-h3, and insulin growth factor-binding protein 7--are necessary for lumen formation. Moreover, lumen formation can be rescued by addition of purified protein to knockdown cultures. Finally, using rheology, we demonstrate that the presence of these matricellular proteins results in significantly stiffer gels, which correlates with enhanced lumen formation. These findings highlight the critical role that fibroblast-derived extracellular matrix components play in EC lumen formation and provide potential insight into the role of fibroblasts in the tumor microenvironment.

  1. Correction of lumen contrast-enhancement influence on non-calcified coronary atherosclerotic plaque quantification on CT.

    Science.gov (United States)

    Kristanto, Wisnumurti; Tuncay, Volkan; Vliegenthart, Rozemarijn; van Ooijen, Peter M A; Oudkerk, Matthijs

    2015-02-01

    Lumen contrast-enhancement influences non-calcified atherosclerotic plaque Hounsfield-unit (HU) values in computed tomography (CT). This study aimed to construct and validate an algorithm to correct for this influence. Three coronary vessel phantoms with 1, 2, and 4 mm circular hollow lumina; with normal and plaque-infested walls were scanned simultaneously in oil using a dual-source CT scanner. Scanning was repeated as the lumina were alternately filled with water and four contrast solutions (100-400 HU, at 100 HU intervals). Images were reconstructed at 0.4 mm x-y pixel size. Pixel-by-pixel comparisons of contrast-enhanced and non-contrast-enhanced images confirmed exponential declining patterns in lumen contrast-enhancement influence on wall HU-values from the lumen border (y = Ae(-λx) + c). The median difference of the inside and outside 2-pixel radius part of the contrast-enhanced coronary phantom wall to the reference (non-contrast-enhanced images) was 45 and 2 HU, respectively. Based on the lumen contrast-enhancement influence patterns, a generalized correction algorithm was formulated. Application of the generalized correction algorithm to the inside 2-pixel radius part of the wall reduced the median difference to the reference to 4 HU. In conclusion, lumen contrast-enhancement influence on the vessel wall can be defined by an exponential approximation, allowing correction of the CT density of the vessel wall closest to the lumen. With this correction, a more accurate determination of vessel wall composition can be made.

  2. Correction of lumen contrast-enhancement influence on non-calcified coronary atherosclerotic plaque quantification on CT

    NARCIS (Netherlands)

    Kristanto, Wisnumurti; Tuncay, Volkan; Vliegenthart, Rozemarijn; van Ooijen, Peter M. A.; Oudkerk, Matthijs

    Lumen contrast-enhancement influences non-calcified atherosclerotic plaque Hounsfield-unit (HU) values in computed tomography (CT). This study aimed to construct and validate an algorithm to correct for this influence. Three coronary vessel phantoms with 1, 2, and 4 mm circular hollow lumina; with

  3. Automatic segmentation of the lumen region in intravascular images of the coronary artery.

    Science.gov (United States)

    Jodas, Danilo Samuel; Pereira, Aledir Silveira; Tavares, João Manuel R S

    2017-08-01

    Image assessment of the arterial system plays an important role in the diagnosis of cardiovascular diseases. The segmentation of the lumen and media-adventitia in intravascular (IVUS) images of the coronary artery is the first step towards the evaluation of the morphology of the vessel under analysis and the identification of possible atherosclerotic lesions. In this study, a fully automatic method for the segmentation of the lumen in IVUS images of the coronary artery is presented. The proposed method relies on the K-means algorithm and the mean roundness to identify the region corresponding to the potential lumen. An approach to identify and eliminate side branches on bifurcations is also proposed to delimit the area with the potential lumen regions. Additionally, an active contour model is applied to refine the contour of the lumen region. In order to evaluate the segmentation accuracy, the results of the proposed method were compared against manual delineations made by two experts in 326 IVUS images of the coronary artery. The average values of the Jaccard measure, Hausdorff distance, percentage of area difference and Dice coefficient were 0.88 ± 0.06, 0.29 ± 0.17  mm, 0.09 ± 0.07 and 0.94 ± 0.04, respectively, in 324 IVUS images successfully segmented. Additionally, a comparison with the studies found in the literature showed that the proposed method is slight better than the majority of the related methods that have been proposed. Hence, the new automatic segmentation method is shown to be effective in detecting the lumen in IVUS images without using complex solutions and user interaction. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Vascular diameter measurement in CT angiography: comparison of model-based iterative reconstruction and standard filtered back projection algorithms in vitro.

    Science.gov (United States)

    Suzuki, Shigeru; Machida, Haruhiko; Tanaka, Isao; Ueno, Eiko

    2013-03-01

    The purpose of this study was to evaluate the performance of model-based iterative reconstruction (MBIR) in measurement of the inner diameter of models of blood vessels and compare performance between MBIR and a standard filtered back projection (FBP) algorithm. Vascular models with wall thicknesses of 0.5, 1.0, and 1.5 mm were scanned with a 64-MDCT unit and densities of contrast material yielding 275, 396, and 542 HU. Images were reconstructed images by MBIR and FBP, and the mean diameter of each model vessel was measured by software automation. Twenty separate measurements were repeated for each vessel, and variance among the repeated measures was analyzed for determination of measurement error. For all nine model vessels, CT attenuation profiles were compared along a line passing through the luminal center on axial images reconstructed with FBP and MBIR, and the 10-90% edge rise distances at the boundary between the vascular wall and the lumen were evaluated. For images reconstructed with FBP, measurement errors were smallest for models with 1.5-mm wall thickness, except those filled with 275-HU contrast material, and errors grew as the density of the contrast material decreased. Measurement errors with MBIR were comparable to or less than those with FBP. In CT attenuation profiles of images reconstructed with MBIR, the 10-90% edge rise distances at the boundary between the lumen and vascular wall were relatively short for each vascular model compared with those of the profile curves of FBP images. MBIR is better than standard FBP for reducing reconstruction blur and improving the accuracy of diameter measurement at CT angiography.

  5. Multiple versus single lumen umbilical venous catheters for newborn infants.

    Science.gov (United States)

    Kabra, N S; Kumar, M; Shah, S S

    2005-07-20

    needed to treat (NNT) or number needed to harm (NNH) was calculated. Three studies qualified for inclusion in this review (Khilnani 1991; Loisel 1996; Soupre 1998). There was a decrease in the ML-UVCs group in the number of additional PIVs used in the first week of life [WMD -1.42, (95% CI -1.74, -1.10), pcatheter malfunction in the ML-UVCs group [typical RR 3.69 (95% CI 0.99, 13.81), p=0.05; RD 0.15 (95% CI 0.03, 0.27), p=0.01; NNH was 7, 95% CI 4, 33; n=99]. The following outcomes were not significantly different in the two groups: clinical sepsis, catheter related blood stream infection, catheter-associated thrombosis, complications related to catheter malposition in heart and great vessels, NEC and early neonatal mortality. The use of ML-UVCs in comparison to SL-UVCs in neonates is associated with decrease in the usage of PIVs in first week of life, but an increase in catheter malfunctions. As the quality of included randomized studies is poor and the estimates of clinically important complications are imprecise, no firm recommendations can be made regarding the choice of UVC. Adequately powered, properly randomized and properly blinded controlled trials are needed that address the effectiveness and safety of ML-UVCs (double and triple lumen) in comparison to SL-UVCs. These studies should also address the impact of type of catheter material.

  6. Linear-regression convolutional neural network for fully automated coronary lumen segmentation in intravascular optical coherence tomography

    Science.gov (United States)

    Yong, Yan Ling; Tan, Li Kuo; McLaughlin, Robert A.; Chee, Kok Han; Liew, Yih Miin

    2017-12-01

    Intravascular optical coherence tomography (OCT) is an optical imaging modality commonly used in the assessment of coronary artery diseases during percutaneous coronary intervention. Manual segmentation to assess luminal stenosis from OCT pullback scans is challenging and time consuming. We propose a linear-regression convolutional neural network to automatically perform vessel lumen segmentation, parameterized in terms of radial distances from the catheter centroid in polar space. Benchmarked against gold-standard manual segmentation, our proposed algorithm achieves average locational accuracy of the vessel wall of 22 microns, and 0.985 and 0.970 in Dice coefficient and Jaccard similarity index, respectively. The average absolute error of luminal area estimation is 1.38%. The processing rate is 40.6 ms per image, suggesting the potential to be incorporated into a clinical workflow and to provide quantitative assessment of vessel lumen in an intraoperative time frame.

  7. Linear-regression convolutional neural network for fully automated coronary lumen segmentation in intravascular optical coherence tomography.

    Science.gov (United States)

    Yong, Yan Ling; Tan, Li Kuo; McLaughlin, Robert A; Chee, Kok Han; Liew, Yih Miin

    2017-12-01

    Intravascular optical coherence tomography (OCT) is an optical imaging modality commonly used in the assessment of coronary artery diseases during percutaneous coronary intervention. Manual segmentation to assess luminal stenosis from OCT pullback scans is challenging and time consuming. We propose a linear-regression convolutional neural network to automatically perform vessel lumen segmentation, parameterized in terms of radial distances from the catheter centroid in polar space. Benchmarked against gold-standard manual segmentation, our proposed algorithm achieves average locational accuracy of the vessel wall of 22 microns, and 0.985 and 0.970 in Dice coefficient and Jaccard similarity index, respectively. The average absolute error of luminal area estimation is 1.38%. The processing rate is 40.6 ms per image, suggesting the potential to be incorporated into a clinical workflow and to provide quantitative assessment of vessel lumen in an intraoperative time frame. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  8. Vessel Operating Units (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data for vessels that are greater than five net tons and have a current US Coast Guard documentation number. Beginning in1979, the NMFS...

  9. Understanding the roles of the thylakoid lumen in photosynthesis regulation

    Directory of Open Access Journals (Sweden)

    Sari eJärvi

    2013-10-01

    Full Text Available It has been known for a long time that the thylakoid lumen provides the environment for oxygen evolution, plastocyanin-mediated electron transfer and photoprotection. More recently lumenal proteins have been revealed to play roles in numerous processes, most often linked with regulating thylakoid biogenesis and the activity and turnover of photosynthetic protein complexes, especially the PSII and NAD(PH dehydrogenase-like complexes. Still, the functions of the majority of lumenal proteins in Arabidopsis thaliana are unknown. Interestingly, while the thylakoid lumen proteome of at least 80 proteins contains several large protein families, individual members of many protein families have highly divergent roles. This is indicative of evolutionary pressure leading to neofunctionalisation of lumenal proteins, emphasizing the important role of thylakoid lumen for photosynthetic electron transfer and ultimately for the plant fitness. Furthermore, the involvement of anterograde and retrograde signaling networks that regulate the expression and activity of lumen proteins is increasingly pertinent. Recent studies have also highlighted the importance of thiol/disulphide modulation in controlling the functions of many lumenal proteins and photosynthetic regulation pathways.

  10. Polarized protein transport and lumen formation during epithelial tissue morphogenesis.

    Science.gov (United States)

    Blasky, Alex J; Mangan, Anthony; Prekeris, Rytis

    2015-01-01

    One of the major challenges in biology is to explain how complex tissues and organs arise from the collective action of individual polarized cells. The best-studied model of this process is the cross talk between individual epithelial cells during their polarization to form the multicellular epithelial lumen during tissue morphogenesis. Multiple mechanisms of apical lumen formation have been proposed. Some epithelial lumens form from preexisting polarized epithelial structures. However, de novo lumen formation from nonpolarized cells has recently emerged as an important driver of epithelial tissue morphogenesis, especially during the formation of small epithelial tubule networks. In this review, we discuss the latest findings regarding the mechanisms and regulation of de novo lumen formation in vitro and in vivo.

  11. Intracranial vessel wall imaging at 7.0 tesla MRI

    NARCIS (Netherlands)

    van der Kolk, A.G.

    2014-01-01

    Intracranial atherosclerosis is one of the main causes of ischemic stroke. Current conventional imaging techniques assessing intracranial arterial disease in vivo only visualize the vessel wall lumen instead of the pathological vessel wall itself. Therefore, not much is known about the imaging

  12. Evaluation of Retinal Vessel Morphology in Patients with Parkinson's Disease Using Optical Coherence Tomography.

    Directory of Open Access Journals (Sweden)

    Robert Kromer

    Full Text Available The retina has been found affected in Parkinson's disease (PD. It is unclear if this is due to neurodegeneration of local dopamine-dependent retinal cells, a result of central nervous degeneration including the optic nerve or retinal small vessel disease. This study aimed to detect changes of the retinal vasculature in PD patients compared to controls.We examined 49 PD patients and 49 age- and sex-matched healthy controls by spectral domain optical coherence tomography (SD-OCT with a circular scan centred at the optic disc. Vessels within the retinal nerve fibre layer were identified by an automated algorithm and thereafter manually labelled as artery or vein. Layer segmentation, vessel lumen and direct surrounding tissue were marked automatically with a grey value and the contrast between both values in relation to the surrounding tissue was calculated. The differences in these grey value ratios among subjects were determined and used as an indicator for differences in vessel morphology. Furthermore, the diameters of the veins and arteries were measured and then compared between the groups.The contrast of retinal veins was significantly lower in PD patients compared to controls, which indicates changes in vessel morphology in PD. The contrast of arteries was not significantly different. Disease duration, disease stage according to Hoehn and Yahr or age did not influence the grey value ratios in PD patients. Vessel diameter in either veins or arteries did not differ between subject groups. The contrast of retinal veins contralateral to the clinically predominant and first affected side was significantly lower compared to the ipsilateral side.Our data show a potential difference of the retinal vasculature in PD patients compared to controls. Vascular changes in the retina of PD patients might contribute to vision-related complaints in PD.

  13. Spermine oxidase promotes bile canalicular lumen formation through acrolein production.

    Science.gov (United States)

    Uemura, Takeshi; Takasaka, Tomokazu; Igarashi, Kazuei; Ikegaya, Hiroshi

    2017-11-01

    Spermine oxidase (SMOX) catalyzes oxidation of spermine to generate spermidine, hydrogen peroxide (H 2 O 2 ) and 3-aminopropanal, which is spontaneously converted to acrolein. SMOX is induced by a variety of stimuli including bacterial infection, polyamine analogues and acetaldehyde exposure. However, the physiological functions of SMOX are not yet fully understood. We investigated the physiological role of SMOX in liver cells using human hepatocellular carcinoma cell line HepG2. SMOX localized to the bile canalicular lumen, as determined by F-actin staining. Knockdown of SMOX reduced the formation of bile canalicular lumen. We also found that phospho-Akt (phosphorylated protein kinase B) was localized to canalicular lumen. Treatment with Akt inhibitor significantly reduced the formation of bile canalicular lumen. Acrolein scavenger also inhibited the formation of bile canalicular lumen. PTEN, phosphatase and tensin homolog and an inhibitor of Akt, was alkylated in a SMOX-dependent manner. Our results suggest that SMOX plays a central role in the formation of bile canalicular lumen in liver cells by activating Akt pathway through acrolein production.

  14. Failure Diameter Resolution Study

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-12-19

    Previously the SURFplus reactive burn model was calibrated for the TATB based explosive PBX 9502. The calibration was based on fitting Pop plot data, the failure diameter and the limiting detonation speed, and curvature effect data for small curvature. The model failure diameter is determined utilizing 2-D simulations of an unconfined rate stick to find the minimum diameter for which a detonation wave propagates. Here we examine the effect of mesh resolution on an unconfined rate stick with a diameter (10mm) slightly greater than the measured failure diameter (8 to 9 mm).

  15. Research vessels

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, P.S.

    The role of the research vessels as a tool for marine research and exploration is very important. Technical requirements of a suitable vessel and the laboratories needed on board are discussed. The history and the research work carried out...

  16. Is quantitative coronary angiography reliable in assessing the late lumen loss of the everolimus-eluting bioresorbable polylactide scaffold in comparison with the cobalt-chromium metallic stent?

    NARCIS (Netherlands)

    Sotomi, Yohei; Onuma, Yoshinobu; Miyazaki, Yosuke; Asano, Taku; Katagiri, Yuki; Tenekecioglu, Erhan; Jonker, Hans; Dijkstra, Jouke; de Winter, Robbert J.; Wykrzykowska, Joanna J.; Stone, Gregg W.; Popma, Jeffrey J.; Kozuma, Ken; Tanabe, Kengo; Serruys, Patrick W.; Kimura, Takeshi

    2017-01-01

    Aims: Immediately after stent/scaffold implantation, quantitative coronary angiography (QCA) in comparison to optical coherence tomography (OCT) more severely underestimates the lumen diameter (LD) in Absorb than in XIENCE. This OCT-QCA discrepancy has not been evaluated at long-term follow-up. The

  17. Evaluation of flow volume and flow patterns in the patent false lumen of chronic aortic dissections using velocity-encoded cine magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Toshihisa; Watanabe, Shigeru; Sakurada, Hideki; Ono, Katsuhiro; Urano, Miharu; Hijikata, Yasuyoshi; Saito, Isao; Masuda, Yoshiaki [Chiba Univ. (Japan). School of Medicine

    2000-10-01

    In 21 patients with chronic aortic dissections and proven patent false lumens, the flow volume and flow patterns in the patent false lumens was evaluated using velocity-encoded cine magnetic resonance imaging (VENC-MRI) and the relationship between the flow characteristics and aortic enlargement was retrospectively examined. Flow patterns in the false lumen were divided into 3 groups: pattern A with primarily antegrade flow (n=6), pattern R with primarily retrograde flow (n=3), and pattern B with bidirectional flow (n=12). In group A, the rate of flow volume in the false lumen compared to the total flow volume in true and false lumens (%TFV) and the average rate of enlargement of the maximum diameter of the dissected aorta per year ({delta}D) were significantly greater than in groups R and B (%TFV: 74.1{+-}0.07 vs 15.2{+-}0.03 vs 11.8{+-}0.04, p<0.01; {delta}D: 3.62{+-}0.82 vs 0 vs 0.58{+-}0.15 mm/year, p<0.05, respectively). There was a significant correlation between %TFV and {delta}D (r=0.79, p<0.0001). Evaluation of flow volume and flow patterns in the patent false lumen using VENC-MRI may be useful for predicting enlargement of the dissected aorta. (author)

  18. Candy-Plug Technique Using an Excluder Aortic Extender for Distal Occlusion of a Large False Lumen Aneurysm in Chronic Aortic Dissection.

    Science.gov (United States)

    Ogawa, Yukihisa; Nishimaki, Hiroshi; Chiba, Kiyoshi; Murakami, Kenji; Sakurai, Yuka; Fujiwara, Keishi; Miyairi, Takeshi; Nakajima, Yasuo

    2016-06-01

    To describe the candy-plug technique using an Excluder aortic extender for distal occlusion of a large false lumen aneurysm in chronic aortic dissection. A 60-year-old female patient with a history of chronic type B aortic dissection and high-dose steroid use for Churg-Strauss syndrome developed a large 6.2 cm maximum diameter false lumen aneurysm. She underwent thoracic endovascular aortic repair from the left common carotid artery to the descending aorta to cover the proximal entry at the level of distal arch, with coil embolization of the left subclavian artery. To occlude the large false lumen from the reentry just below the level of the left renal artery ostium, a modified 32×45-mm Excluder aortic extender was deployed in the false lumen through the reentry, and a 16-mm Amplatzer Vascular Plug I was deployed in the waist of the modified Excluder aortic extender for complete occlusion. No obvious technical complication was seen. Contrast-enhanced computed tomography at 1 and 14 months revealed no endoleaks and showed complete false lumen thrombosis. The candy-plug technique using the Excluder aortic extender is feasible for occlusion of a large false lumen aneurysm in chronic aortic dissection. © The Author(s) 2016.

  19. Evaluation of flow volume and flow patterns in the patent false lumen of chronic aortic dissections using velocity-encoded cine magnetic resonance imaging

    International Nuclear Information System (INIS)

    Inoue, Toshihisa; Watanabe, Shigeru; Sakurada, Hideki; Ono, Katsuhiro; Urano, Miharu; Hijikata, Yasuyoshi; Saito, Isao; Masuda, Yoshiaki

    2000-01-01

    In 21 patients with chronic aortic dissections and proven patent false lumens, the flow volume and flow patterns in the patent false lumens was evaluated using velocity-encoded cine magnetic resonance imaging (VENC-MRI) and the relationship between the flow characteristics and aortic enlargement was retrospectively examined. Flow patterns in the false lumen were divided into 3 groups: pattern A with primarily antegrade flow (n=6), pattern R with primarily retrograde flow (n=3), and pattern B with bidirectional flow (n=12). In group A, the rate of flow volume in the false lumen compared to the total flow volume in true and false lumens (%TFV) and the average rate of enlargement of the maximum diameter of the dissected aorta per year (ΔD) were significantly greater than in groups R and B (%TFV: 74.1±0.07 vs 15.2±0.03 vs 11.8±0.04, p<0.01; ΔD: 3.62±0.82 vs 0 vs 0.58±0.15 mm/year, p<0.05, respectively). There was a significant correlation between %TFV and ΔD (r=0.79, p<0.0001). Evaluation of flow volume and flow patterns in the patent false lumen using VENC-MRI may be useful for predicting enlargement of the dissected aorta. (author)

  20. Quantitative coronary CT angiography: absolute lumen sizing rather than %stenosis predicts hemodynamically relevant stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Plank, Fabian [Innsbruck Medical University, Department of Radiology, Innsbruck (Austria); Innsbruck Medical University, Department of Internal Medicine III - Cardiology, Innsbruck (Austria); Burghard, Philipp; Mayr, Agnes; Klauser, Andrea; Feuchtner, Gudrun [Innsbruck Medical University, Department of Radiology, Innsbruck (Austria); Friedrich, Guy; Dichtl, Wolfgang [Innsbruck Medical University, Department of Internal Medicine III - Cardiology, Innsbruck (Austria); Wolf, Florian [Vienna Medical University, Department of Cardiovascular and Interventional Radiology, Vienna (Austria)

    2016-11-15

    To identify the most accurate quantitative coronary stenosis parameter by CTA for prediction of functional significant coronary stenosis resulting in coronary revascularization. 160 consecutive patients were prospectively examined with CTA. Proximal coronary stenosis was quantified by minimal lumen area (MLA) and minimal lumen diameter (MLD), %area and %diameter stenosis. Lesion length (LL) was measured. The reference standard was invasive coronary angiography (ICA) (>70 % stenosis, FFR <0.8). 210 coronary segments were included (59 % positive). MLA of ≤1.8 mm{sup 2} was identified as the optimal cut-off (c = 0.97, p < 0.001; 95 % CI 0.94-0.99) (sensitivity 90.9 %, specificity 89.3 %) for prediction of functional-relevant stenosis (for MLA >2.1 mm{sup 2} sensitivity was 100 %). The optimal cut-off for MLD was 1.2 mm (c = 0.92; p < 0.001; 95 % CI 0.88-95) (sensitivity 90.9, specificity 85.2) while %area and %diameter stenosis were less accurate (c = 0.89; 95 % CI 0.84-93, c = 0.87; 95 % CI 0.82-92, respectively, with thresholds at 73 % and 61 % stenosis). Accuracy for LL was c = 0.74 (95 % CI 0.67-81), and for LL/MLA and LL/MLD ratio c = 0.90 and c = 0.84. MLA ≤1.8 mm{sup 2} and MLD ≤1.2 mm are the most accurate cut-offs for prediction of haemodynamically significant stenosis by ICA, with a higher accuracy than relative % stenosis. (orig.)

  1. [Telescopic adhesive anastomosis of small blood vessel applied in formation of arteriovenous fistula for hemodialysis].

    Science.gov (United States)

    Shen, G; Leng, Y; Rong, G

    1997-03-01

    The formation of an arteriovenous fistual for dialysis by routine interrupted sutures anastomosing the vein and artery is difficult to perform and time-consuming. A new method, telescopic adhesive anastomosis was studied and applied in 10 hemodialysis patients, who were in need of an arteriovenous fistula. The external diameter of the vessels anastomosed was 2.40 +/- 0.20 mm (radial artery) or 2.40 +/- 0.35 mm (cephalic vein). After thorough debridement of the vascular ends, the arterial end was put in the venous lumen. In order to fix the telescopic vessels, two stitches were applied 180 degrees apart from each other and tied. Each stitch was inserted from vein (penetrating the whole wall) to artery (just through the adventitia and partial thickness of the media vasorum). The distance from the stitch to the edge of the vein was 0.5 mm, and that of the artery was approximated to the external diameter of the vessle. The medical adhesive was then applied for sealing the anastomotic adventitia. Ten seconds were given for the solidification of the adhesive. The patients were followed up for 8 months. The patency rate was 100%, and the rate of blood flow was more than 300 ml/min (measured by ultrasonography). It was shown that this method could be managed easily and quickly, and the so-formed fistula would fulfill the need of hemodialysis.

  2. ASSEMBLY AND METHOD FOR DISINFECTING LUMENS OF MEDICAL DEVICES

    DEFF Research Database (Denmark)

    2010-01-01

    comprising -a medical device for transporting fluids having a lumen and a first connector part, and -at least one light source configured to emit light having bactericidal effect which light source has a corresponding second connector part, and comprises an optical window being transparent for light from...

  3. One lung ventilation using double‑lumen tubes: Initial experience ...

    African Journals Online (AJOL)

    2014-05-09

    May 9, 2014 ... Background: One lung ventilation (OLV) is a technique routinely used in thoracic anesthesia to facilitate thoracic surgery. Double‑lumen tubes (DLT) remain the most popular and reliable choice for one lung ventilation especially in adult patients though use in Nigeria is limited. This study aimed to describe ...

  4. Hollow fiber membrane lumen modified by polyzwitterionic grafting

    KAUST Repository

    Le, Ngoc Lieu

    2016-08-24

    In this study, we demonstrate an effective way to modify the lumen of polyetherimide hollow fibers by grafting zwitterionic poly(sulfobetaine) to increase the membrane resistance to fouling. Surface-selective grafting of the protective hydrogel layers has been achieved in a facile two-step process. The first step is the adsorption of a macromolecular redox co-initiator on the lumen-side surface of the membrane, which in the second step, after flushing the lumen of the membrane with a solution comprising monomers and a complementary redox initiator, triggers the in situ cross-linking copolymerization at room temperature. The success of grafting reaction has been verified by the surface elemental analyses using X-ray photoelectron spectroscopy (XPS) and the surface charge evaluation using zeta potential measurements. The hydrophilicity of the grafted porous substrate is improved as indicated by the change of contact angle value from 44° to 30°, due to the hydration layer on the surface produced by the zwitterionic poly(sulfobetaine). Compared to the pristine polyetherimide (PEI) substrate, the poly(sulfobetaine) grafted substrates exhibit high fouling resistance against bovine serum albumin (BSA) adsorption, E. coli attachment and cell growth on the surface. Fouling minimization in the lumen is important for the use of hollow fibers in different processes. For instance, it is needed to preserve power density of pressure-retarded osmosis (PRO). In high-pressure PRO tests, a control membrane based on PEI with an external polyamide selective layer was seriously fouled by BSA, leading to a high water flux drop of 37%. In comparison, the analogous membrane, whose lumen was modified with poly(sulfobetaine), not only had a less water flux decline but also had better flux recovery, up to 87% after cleaning and hydraulic pressure impulsion. Clearly, grafting PRO hollow fiber membranes with zwitterionic polymeric hydrogels as a protective layer potentially sustains PRO

  5. Public relations ve firmě LUMEN INTERNATIONAL a.s.

    OpenAIRE

    DICHTLOVÁ, Hana

    2012-01-01

    Goal of the thesis was to assess current significance and usage of public relations in LUMEN INTERNATIONAL a.s. company and to create plan of another development. The author analysed development and current situation of public relations in LUMEN holding. There are a few suggestions in this thesis how to improve public relations in whole LUMEN holding.

  6. Design and in-vitro evaluation of a tissue engineered large vessel prosthesis

    Science.gov (United States)

    Mahmood, Ayesha

    Tissue engineering of large diameter blood vessels can offer a promising long-term solution to the large population suffering from congenital vascular defects and other vascular disease. In this report design, assembly, in vitro maturation and evaluation of a large diameter, chitosan-based prosthesis is described. To facilitate cell adhesion and proliferation, collagen was included as a scaffold component to a chitosan scaffold. In vitro studies evaluated the role of collagen content, crosslinker type and crosslinking density on degradation kinetics, mechanical properties and cellular interactions. Finally, the vessel scaffold (ID = 12 mm, OD = 15 mm) was fabricated from a moderately cross-linked, 90%/10% chitosan/collagen material. A tubular scaffold with gradient porosity and interconnected pores was generated by controlled freezing and lyophilization of the polymer. For graft culture laminar and pulsatile flow systems were designed and porous scaffolds were seeded with vascular cells under static conditions. Laminar system grafts were seeded and cultured/analyzed over an 8 week period (15ml/min). For the pulsatile system SMC were seeded and after 2 weeks of pulsatile flow culture (360ml/min, 82 beats/min) microvascular EC were seeded lumenally to initiate a microvascular network followed by aortic EC seeding at 3 weeks. For both systems, cell viability at different culture periods showed the formation of high density of cell within few weeks of graft culture. However, the pulsatile flow system graft showed a significant increase in mechanical properties and ECM protein (collagen and elastin) deposition overtime. This novel chitosan based tissue engineered vascular graft shows promising results for large vessel replacements.

  7. Reactor vessel

    NARCIS (Netherlands)

    Makkee, M.; Kapteijn, F.; Moulijn, J.A.

    1999-01-01

    A reactor vessel (1) comprises a reactor body (2) through which channels (3) are provided whose surface comprises longitudinal inwardly directed parts (4) and is provided with a catalyst (6), as well as buffer bodies (8, 12) connected to the channels (3) on both sides of the reactor body (2) and

  8. Evolution of regular geometrical shapes in fiber lumens

    KAUST Repository

    Le, Ngoc Lieu

    2017-08-17

    The geometry of polymeric hollow fibers for hemodialysis or desalination is a key factor determining their performance. Deformations are frequently observed, but they are rather random. Here we were able to exactly control the shape evolution of the internal channels or lumens of polymeric hollow fibers, leading to polygonal geometries with increasing number of sides. The elasticity of the incipient channel skin and instabilities during fiber formation are affected by the internal coagulant fluid composition and flow rate; and highly influence the polygonal shape. We propose a holistic explanation by analyzing the thermodynamic, kinetic and rheological aspects involved in the skin formation and their synergy.

  9. Containment vessel

    International Nuclear Information System (INIS)

    Zbirohowski-Koscia, K.F.; Roberts, A.C.

    1980-01-01

    A concrete containment vessel for nuclear reactors is disclosed that is spherical and that has prestressing tendons disposed in first, second and third sets, the tendons of each set being all substantially concentric and centred around a respective one of the three orthogonal axes of the sphere; the tendons of the first set being anchored at each end at a first anchor rib running around a circumference of the vessel, the tendons of the second set being anchored at each end at a second anchor rib running around a circumference of the sphere and disposed at 90 0 to the first rib, and the tendons of the third set being anchored some to the first rib and the remainder to the second rib. (author)

  10. Reactor pressure vessel nozzle

    Science.gov (United States)

    Challberg, Roy C.; Upton, Hubert A.

    1994-01-01

    A nozzle for joining a pool of water to a nuclear reactor pressure vessel includes a tubular body having a proximal end joinable to the pressure vessel and a distal end joinable in flow communication with the pool. The body includes a flow passage therethrough having in serial flow communication a first port at the distal end, a throat spaced axially from the first port, a conical channel extending axially from the throat, and a second port at the proximal end which is joinable in flow communication with the pressure vessel. The inner diameter of the flow passage decreases from the first port to the throat and then increases along the conical channel to the second port. In this way, the conical channel acts as a diverging channel or diffuser in the forward flow direction from the first port to the second port for recovering pressure due to the flow restriction provided by the throat. In the backflow direction from the second port to the first port, the conical channel is a converging channel and with the abrupt increase in flow area from the throat to the first port collectively increase resistance to flow therethrough.

  11. Computed Tomographic Window Setting for Bronchial Measurement to Guide Double-Lumen Tube Size.

    Science.gov (United States)

    Seo, Jeong-Hwa; Bae, Jinyoung; Paik, Hyesun; Koo, Chang-Hoon; Bahk, Jae-Hyon

    2018-04-01

    The bronchial diameter measured on computed tomography (CT) can be used to guide double-lumen tube (DLT) sizes objectively. The bronchus is known to be measured most accurately in the so-called bronchial CT window. The authors investigated whether using the bronchial window results in the selection of more appropriately sized DLTs than using the other windows. CT image analysis and prospective randomized study. Tertiary hospital. Adults receiving left-sided DLTs. The authors simulated selection of DLT sizes based on the left bronchial diameters measured in the lung (width 1,500 Hounsfield unit [HU] and level -700 HU), bronchial (1,000 HU and -450 HU), and mediastinal (400 HU and 25 HU) CT windows. Furthermore, patients were randomly assigned to undergo imaging with either the bronchial or mediastinal window to guide DLT sizes. Using the underwater seal technique, the authors assessed whether the DLT was appropriately sized, undersized, or oversized for the patient. On 130 CT images, the bronchial diameter (9.9 ± 1.2 mm v 10.5 ± 1.3 mm v 11.7 ± 1.3 mm) and the selected DLT size were different in the lung, bronchial, and mediastinal windows, respectively (p window suggested too small DLTs (28 Fr) for adults. In the prospective study, oversized tubes were chosen less frequently in the bronchial window than in the mediastinal window (6/110 v 23/111; risk ratio 0.38; 95% CI 0.19-0.79; p = 0.003). No tubes were undersized after measurements in these two windows. The bronchial measurement in the bronchial window guided more appropriately sized DLTs compared with the lung or mediastinal windows. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Small diameter carbon nanopipettes

    Science.gov (United States)

    Singhal, Riju; Bhattacharyya, Sayan; Orynbayeva, Zulfiya; Vitol, Elina; Friedman, Gary; Gogotsi, Yury

    2010-01-01

    Nanoscale multifunctional carbon probes facilitate cellular studies due to their small size, which makes it possible to interrogate organelles within living cells in a minimally invasive fashion. However, connecting nanotubes to macroscopic devices and constructing an integrated system for the purpose of fluid and electrical signal transfer is challenging, as is often the case with nanoscale components. We describe a non-catalytic chemical vapor deposition based method for batch fabrication of integrated multifunctional carbon nanopipettes (CNPs) with tip diameters much smaller (10-30 nm) than previously reported (200 nm and above) and approaching those observed for multiwalled carbon nanotubes. This eliminates the need for complicated attachment/assembly of nanotubes into nanofluidic devices. Variable tip geometries and structures were obtained by controlled deposition of carbon inside and outside quartz pipettes. We have shown that the capillary length and gas flow rate have a marked effect on the carbon deposition. This gives us a flexible protocol, useful for growing carbon layers of different thicknesses at selective locations on a glass pipette to yield a large variety of cellular probes in bulk quantities. The CNPs possess an open channel for fluid transfer with the carbon deposited inside at 875 °C behaving like an amorphous semiconductor. Vacuum annealing of the CNP tips at temperatures up to 2000 °C yields graphitic carbon structures with an increase in conductivity of two orders of magnitude. Penetration of the integrated carbon nanoprobes into cells was shown to produce minimal Ca2+ signals, fast recovery of basal Ca2+ levels and no adverse activation of the cellular metabolism during interrogation times as long as 0.5-1 h.

  13. The DIAMET campaign

    Science.gov (United States)

    Vaughan, G.

    2012-04-01

    DIAMET (DIAbatic influences on Mesoscale structures in ExTratropical storms) is a joint project between the UK academic community and the Met Office. Its focus is on understanding and predicting mesoscale structures in synoptic-scale storms, and in particular on the role of diabatic processes in generating and maintaining them. Such structures include fronts, rain bands, secondary cyclones, sting jets etc, and are important because much of the extreme weather we experience (e.g. strong winds, heavy rain) comes from such regions. The project conducted two field campaigns in the autumn of 2011, from September 14 - 30 and November 24 - December 14, based around the FAAM BAe146 aircraft with support from ground-based radar and radiosonde measurements. Detailed modelling, mainly using the Met Office Unified model, supported the planning and interpretation of these campaigns. This presentation will give a brief overview of the campaigns. Both in September and November-December the weather regime was westerly, with a strong jet stream directed across the Atlantic. Three IOPs were conducted in September, to observe a convective band ahead of an upper-level trough, waves on a long trailing cold front, and a warm conveyor belt associated with a secondary cyclone. In November-December six IOPs were conducted, to observe frontal passages and high winds. This period was notable for a number of very strong windstorms passing across the north of the UK, and gave us an opportunity to examine bent-back warm fronts in the southern quadrant of these storms where the strongest winds are found. The case studies fell into two basic patterns. In the majority of cases, dropsonde legs at high level were used to obtain a cross-section of winds and thermodynamic structure (e.g. across a front), followed by in situ legs at lower levels (generally where the temperature was between 0 and -10°) to examine microphysical processes, especially ice multiplication and the extent of supercooled water

  14. Coronary lumen volume to myocardial mass ratio in primary microvascular angina.

    Science.gov (United States)

    Grover, Rominder; Leipsic, Jonathon A; Mooney, John; Kueh, Shaw-Hua; Ohana, Mickael; Nørgaard, Bjarne L; Eftekhari, Ashkan; Bax, Jeroen J; Murphy, Darra T; Hague, Cameron J; Seidman, Michael A; Blanke, Philipp; Sedlak, Tara; Sellers, Stephanie L

    2017-11-01

    Microvascular angina (MVA) is an incompletely understood clinical entity. Computational analysis of coronary Computed Tomography Angiography (CTA) has shown an association between low coronary lumen volume to myocardial mass (V/M) ratio and lower Fractional Flow Reserve values, independent of plaque measures. We hypothesized that low V/M ratio may be present in patients with MVA. A retrospective case-control analysis was performed using patients fulfilling guideline criteria for MVA with controls matched for age, gender, coronary risk factors and atherosclerotic plaque burden. V/M was extracted off site (Heartflow Inc; Redwood City, CA) employing allometric scaling laws that allow the definition of the coronary circulation beyond the epicardium. FFR CT values were calculated in the major epicardial coronary arteries for each group. A total of 30 patients with MVA and 32 matched controls were included in the study. Mean total coronary lumen volume (2302 mm 3  ± 109 vs 2978 mm 3  ± 134, p < 0.001) and mean myocardial mass (90.4 g ± 13.7 vs 100.4 g ± 20.1, p = 0.029) were lower in MVA patients compared to controls. Mean V/M ratio was significantly lower in MVA compared to controls (25.6 mm 3 /g ± 5.9 vs 30.0 mm 3 /g ± 6.5, p = 0.007; c-statistic 0.69). V/M ratio did not differ significantly between subclasses of angina severity (p = 0.747). No difference in mean nadir FFR CT values was found between MVA and control groups in the LAD (0.86 ± 0.07 vs 0.83 ± 0.07, p = 0.154), LCX (0.90 ± 0.05 vs 0.90 ± 0.06, p = 0.240) and RCA (0.90 ± 0.04 vs 0.90 ± 0.03, p = 0.773) vessels. Patients with microvascular angina demonstrate a significantly lower coronary CTA-derived coronary volume/myocardial mass ratio than asymptomatic controls. Copyright © 2017 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

  15. Differences in mean fibre diameter and fibre diameter variance in ...

    African Journals Online (AJOL)

    sampled at five different body locations (Figure 1) at an age of 15 months. Samples were analysed by the Wool Testing. Bureaux, using an Optical Fibre Diameter Analyser which measured 4000 individual fibres in each sample. Apart from the mean, the variance of fibre diameter within samples was available. The statistical ...

  16. A novel photochemical cross-linking technology to improve luminal gain, vessel compliance, and buckling post-angioplasty in porcine arteries.

    Science.gov (United States)

    Munger, Karen A; Downey, Therese M; Haberer, Barb; Pohlson, Katie; Marshall, Lindsey L; Utecht, Ronald E

    2016-02-01

    Development of substituted 1,8-naphthalimides for photochemical cross-linking of biomolecules is the focus of this research. This study describes limited cross-linking of collagen in the artery wall to control recoil and buckling in arteries following balloon angioplasty. Isolated porcine arteries were overstretched (25%) with balloon angioplasty (BA) +/- light-activated naphthalimide treatment (NVS). Lumen size and recoil were measured as retention of stretch after angioplasty. Cross-sectional compliance and distensibility coefficients were measured as slope of cross-sectional area versus increasing hydrostatic pressure. Buckling was measured, with 30% axial pre-stretch and 200 mmHg, as deviation from the center line. Electron microscopy evaluation of collagen fibers was conducted. Uninjured arteries have low compliance and low levels of buckling, whereas the BA-injured arteries demonstrated much greater compliance and buckling behavior. Treatment of the injured artery with NVS reduced buckling and demonstrated compliance midway between the two groups while retaining the increased luminal diameter imparted by angioplasty compared to untreated vessels. In summary, limited collagen cross-linking with NVS treatment resulted in lumen retention, as well as improved compliance without the accompanying rigidity and stiffness of conventional stent therapy or current cross-linking materials. This treatment shows great promise for dilation, repair and strengthening of arteries damaged by injury or vascular disease. © 2015 Wiley Periodicals, Inc.

  17. Automated quantification of bronchiectasis, airway wall thickening and lumen tapering in chest CT

    DEFF Research Database (Denmark)

    Perez-Rovira, Adria; Kuo, Wieying; Petersen, Jens

    Purpose: To automatically quantify airway structural properties visualised on CT in children with cystic fibrosis (CF) and controls, including: bronchiectasis, airway wall thickening, and lumen tapering. Methods and materials: The 3D surface of the airway lumen, outer wall, and bronchial arteries...

  18. Preparation of lumen-loaded kenaf pulp with magnetite (Fe3O4)

    International Nuclear Information System (INIS)

    Zakaria, S.; Ong, B.H.; Ahmad, S.H.; Abdullah, M.; Yamauchi, T.

    2005-01-01

    Magnetic pulps were prepared from unbleached kenaf (hibiscus cannabinus L.) kraft pulps. Fe 3 O 4 or magnetite powder was used to load into the pulp's lumen and pit. Aluminum sulphate [Al 2 (SO 4 ) 3 ] (alum) and polyethylenimine (PEI), both mainly function as retention aid were used throughout the experiment and found to be beneficial in the preparation of this magnetic pulps. The ash content method was used to determine the amount of magnetite retained in the lumen and pit. The utilization of PEI up to 2% per pulp fibres was found to be the best result on lumen loading. The deposition of magnetite powder in lumen and pit is found decrease as the addition of PEI used is more than 2% per pulp fibres. Scanning electron microscope (SEM) clearly shows the distribution of magnetite deposited in the lumen. Tensile index and folding endurance of the loaded fibre decreased slightly as the percentage of loading pigment increased

  19. Analysis of nuclear reactor pressure vessel flanges

    International Nuclear Information System (INIS)

    Oliveira, C.A.N. de; Augusto, O.B.

    1985-01-01

    This work proposes a methodology for the structural analysis of high diameter nuclear reactor pressure vessel flanges. In the analysis the vessel is divided into shell-of-revolution elements, the flanges are represented by rigid rings, and the bolts are treated as beams. The flexibility method is used for solving the problem, and the results are compared with results obtained by the finite element method. (Author) [pt

  20. Wheel Diameter and Speedometer Reading

    Science.gov (United States)

    Murray, Clifton

    2010-01-01

    Most introductory physics students have seen vehicles with nonstandard wheel diameters; some may themselves drive "low-rider" cars or "big-wheel" pickup trucks. But how does changing wheel diameter affect speedometer readout for a given speed? Deriving the answer can be followed readily by students who have been introduced to rotation, and it…

  1. The passive biomechanics of human pelvic collecting lymphatic vessels.

    Directory of Open Access Journals (Sweden)

    Dimitrios Athanasiou

    Full Text Available The lymphatic system has a major significance in the metastatic pathways in women's cancers. Lymphatic pumping depends on both extrinsic and intrinsic mechanisms, and the mechanical behavior of lymphatic vessels regulates the function of the system. However, data on the mechanical properties and function of human lymphatics are lacking. Our aim is to characterize, for the first time, the passive biomechanical behavior of human collecting lymphatic vessels removed at pelvic lymph node dissection during primary debulking surgeries for epithelial ovarian cancer. Isolated vessels were cannulated and then pressurized at varying levels of applied axial stretch in a calcium-free Krebs buffer. Pressurized vessels were then imaged using multi-photon microscopy for collagen-elastin structural composition and fiber orientation. Both pressure-diameter and force-elongation responses were highly nonlinear, and axial stretching of the vessel served to decrease diameter at constant pressure. Pressure-diameter behavior for the human vessels is very similar to data from rat mesenteric vessels, though the human vessels were approximately 10× larger than those from rats. Multiphoton microscopy revealed the vessels to be composed of an inner layer of elastin with an outer layer of aligned collagen fibers. This is the first study that successfully described the passive biomechanical response and composition of human lymphatic vessels in patients with ovarian cancer. Future work should expand on this knowledge base with investigations of vessels from other anatomical locations, contractile behavior, and the implications on metastatic cell transport.

  2. Vessel Operator System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operator cards are required for any operator of a charter/party boat and or a commercial vessel (including carrier and processor vessels) issued a vessel permit from...

  3. Induction of embolism in xylem conduits of pre-defined diameter

    NARCIS (Netherlands)

    Ieperen, van W.; Nijsse, J.; Keijzer, C.J.; Meeteren, van U.

    2001-01-01

    A new method is presented that enables the induction of embolisms in a fraction of all xylem vessels, based on diameter, at one cut end of a stem segment. The method is based on the different capillary characteristic of xylem vessels of different cross-sectional size. To verify the method, air

  4. Nuclear reactor vessel fuel thermal insulating barrier

    Energy Technology Data Exchange (ETDEWEB)

    Keegan, C. Patrick; Scobel, James H.; Wright, Richard F.

    2013-03-19

    The reactor vessel of a nuclear reactor installation which is suspended from the cold leg nozzles in a reactor cavity is provided with a lower thermal insulating barrier spaced from the reactor vessel that has a hemispherical lower section that increases in volume from the center line of the reactor to the outer extent of the diameter of the thermal insulating barrier and smoothly transitions up the side walls of the vessel. The space between the thermal insulating harrier and the reactor vessel forms a chamber which can be flooded with cooling water through passive valving to directly cool the reactor vessel in the event of a severe accident. The passive inlet valve for the cooling water includes a buoyant door that is normally maintained sealed under its own weight and floats open when the cavity is Hooded. Passively opening steam vents are also provided.

  5. An artificial blood vessel implanted three-dimensional microsystem for modeling transvascular migration of tumor cells.

    Science.gov (United States)

    Wang, Xue-Ying; Pei, Ying; Xie, Min; Jin, Zi-He; Xiao, Ya-Shi; Wang, Yang; Zhang, Li-Na; Li, Yan; Huang, Wei-Hua

    2015-02-21

    Reproducing a tumor microenvironment consisting of blood vessels and tumor cells for modeling tumor invasion in vitro is particularly challenging. Here, we report an artificial blood vessel implanted 3D microfluidic system for reproducing transvascular migration of tumor cells. The transparent, porous and elastic artificial blood vessels are obtained by constructing polysaccharide cellulose-based microtubes using a chitosan sacrificial template, and possess excellent cytocompatibility, permeability, and mechanical characteristics. The artificial blood vessels are then fully implanted into the collagen matrix to reconstruct the 3D microsystem for modeling transvascular migration of tumor cells. Well-defined simulated vascular lumens were obtained by proliferation of the human umbilical vein endothelial cells (HUVECs) lining the artificial blood vessels, which enables us to reproduce structures and functions of blood vessels and replicate various hemodynamic parameters. Based on this model, the adhesion and transvascular migration of tumor cells across the artificial blood vessel have been well reproduced.

  6. Claudin5a is required for proper inflation of Kupffer's vesicle lumen and organ laterality.

    Directory of Open Access Journals (Sweden)

    Jeong-Gyun Kim

    Full Text Available Left-right asymmetric organ development is critical to establish a proper body plan of vertebrates. In zebrafish, the Kupffer's vesicle (KV is a fluid-filled sac which controls asymmetric organ development, and a properly inflated KV lumen by means of fluid influx is a prerequisite for the asymmetric signal transmission. However, little is known about the components that support the paracellular tightness between the KV luminal epithelial cells to sustain hydrostatic pressure during KV lumen expansion. Here, we identified that the claudin5a (cldn5a is highly expressed at the apical surface of KV epithelial cells and tightly seals the KV lumen. Downregulation of cldn5a in zebrafish showed a failure in organ laterality that resulted from malformed KV. In addition, accelerated fluid influx into KV by combined treatment of forskolin and 3-isobutyl-1-methylxanthine failed to expand the partially-formed KV lumen in cldn5a morphants. However, malformed KV lumen and defective heart laterality in cldn5a morphants were significantly rescued by exogenous cldn5a mRNA, suggesting that the tightness between the luminal epithelial cells is important for KV lumen formation. Taken together, these findings suggest that cldn5a is required for KV lumen inflation and left-right asymmetric organ development.

  7. Claudin5a is required for proper inflation of Kupffer's vesicle lumen and organ laterality.

    Science.gov (United States)

    Kim, Jeong-Gyun; Bae, Sung-Jin; Lee, Hye Shin; Park, Ji-Hyeon; Kim, Kyu-Won

    2017-01-01

    Left-right asymmetric organ development is critical to establish a proper body plan of vertebrates. In zebrafish, the Kupffer's vesicle (KV) is a fluid-filled sac which controls asymmetric organ development, and a properly inflated KV lumen by means of fluid influx is a prerequisite for the asymmetric signal transmission. However, little is known about the components that support the paracellular tightness between the KV luminal epithelial cells to sustain hydrostatic pressure during KV lumen expansion. Here, we identified that the claudin5a (cldn5a) is highly expressed at the apical surface of KV epithelial cells and tightly seals the KV lumen. Downregulation of cldn5a in zebrafish showed a failure in organ laterality that resulted from malformed KV. In addition, accelerated fluid influx into KV by combined treatment of forskolin and 3-isobutyl-1-methylxanthine failed to expand the partially-formed KV lumen in cldn5a morphants. However, malformed KV lumen and defective heart laterality in cldn5a morphants were significantly rescued by exogenous cldn5a mRNA, suggesting that the tightness between the luminal epithelial cells is important for KV lumen formation. Taken together, these findings suggest that cldn5a is required for KV lumen inflation and left-right asymmetric organ development.

  8. Diameter 2 properties and convexity

    Czech Academy of Sciences Publication Activity Database

    Abrahamsen, T. A.; Hájek, Petr Pavel; Nygaard, O.; Talponen, J.; Troyanski, S.

    2016-01-01

    Roč. 232, č. 3 (2016), s. 227-242 ISSN 0039-3223 R&D Projects: GA ČR GA16-07378S Institutional support: RVO:67985840 Keywords : diameter 2 property * midpoint locally uniformly rotund * Daugavet property Subject RIV: BA - General Mathematics Impact factor: 0.535, year: 2016 https://www.impan.pl/pl/wydawnictwa/czasopisma-i-serie-wydawnicze/studia- mathematica /all/232/3/91534/diameter-2-properties-and-convexity

  9. Lumen Maintenance Testing of the Philips 60-Watt Replacement Lamp L Prize Entry

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, Kelly L.; Hafen, Ryan P.; Hathaway, John E.; McCullough, Jeffrey J.

    2012-09-01

    This paper describes testing conducted to evaluate the Philips' L Prize award winning 60-watt LED replacement product's ability to meet the lifetime/lumen maintenance requirement of the competition, which was: "having 70 percent of the lumen value under subparagraph (A) [producing a luminous flux greater than 900 lumens] exceeding 25,000 hours under typical conditions expected in residential use." A custom test apparatus was designed and constructed for this testing and a statistical approach was developed for use in evaluating the test results. This will be the only publicly available, third-party data set of long-term LED product operation.

  10. The influence of lumenal pH on the severity of acute radiation enteritis

    International Nuclear Information System (INIS)

    Delaney, J.P.; Kimm, G.E.; Bonsack, M.E.

    1992-01-01

    The severity of acute radiation injury to small bowel mucosa in rats was studied as a function of lumenal pH at the time of irradiation. Indices of injury were surviving crypt numbers, mucosal height and mucous-containing goblet cells. Animals were sacrificed 5 days postirradiation. For all three parameters and on each day postirradiation, the pH 9 segment showed less damage than segments with lumenal pH 7 or 5. The authors conclude that lumenal pH at the time of irradiation plays a significant role in the severity of acute mucosal injury. Alkaline pH is relatively protective. (author)

  11. Successful Embolization Therapy through Reentry Tear in the Right Subclavian Artery for Treating Patent False Lumen in the Aortic Arch Formed after Type A Dissection Repair

    Science.gov (United States)

    Ishii, Hirohito; Nakamura, Kunihide; Nakamura, Eisaku; Furukawa, Koji; Ochiai, Kouichiro

    2017-01-01

    A 73-year-old woman had undergone hemiarch replacement with primary entry resection for treating acute type A dissection 6 years ago. Postoperative computed tomography (CT) showed a patent false lumen (FL) in the aortic arch and a reentry tear in the right subclavian artery. The remaining aortic arch enlarged, which resulted in formation of a 55-mm-diameter aneurysm. We performed reentry occlusion using embolization with glue and coil. The patient’s clinical course after the procedure was uneventful, and subsequent CT showed that FL was thrombosed and had decreased in size. PMID:29147154

  12. Double-lumen tubes and auto-PEEP during one-lung ventilation.

    Science.gov (United States)

    Spaeth, J; Ott, M; Karzai, W; Grimm, A; Wirth, S; Schumann, S; Loop, T

    2016-01-01

    Double-lumen tubes (DLT) are routinely used to enable one-lung-ventilation (OLV) during thoracic anaesthesia. The flow-dependent resistance of the DLT's bronchial limb may be high as a result of its narrow inner diameter and length, and thus potentially contribute to an unintended increase in positive end-expiratory pressure (auto-PEEP). We therefore studied the impact of adult sized DLTs on the dynamic auto-PEEP during OLV. In this prospective clinical study, dynamic auto-PEEP was determined in 72 patients undergoing thoracic surgery, with right- and left-sided DLTs of various sizes. During OLV, air trapping was provoked by increasing inspiration to expiration ratio from 1:2 to 2:1 (five steps). Based on measured flow rate, airway pressure (Paw) and bronchial pressure (Pbronch), the pressure gradient across the DLT (ΔPDLT) and the total auto-PEEP in the respiratory system (i.e. the lungs, the DLT and the ventilator circuit) were determined. Subsequently the DLT's share in total auto-PEEP was calculated. ΔPDLT was 2.3 (0.7) cm H2O over the entire breathing cycle. At the shortest expiratory time the mean total auto-PEEP was 2.9 (1.5) cm H2O (range 0-5.9 cm H2O). The DLT caused 27 to 31% of the total auto-PEEP. Size and side of the DLT's bronchial limb did not impact auto-PEEP significantly. Although the DLT contributes to the overall auto-PEEP, its contribution is small and independent of size and side of the DLT's bronchial limb. The choice of DLT does not influence the risk of auto-PEEP during OLV to a clinically relevant extent. DRKS00005648. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Segmentation of the lumen and media-adventitia boundaries of the common carotid artery from 3D ultrasound images

    Science.gov (United States)

    Ukwatta, E.; Awad, J.; Ward, A. D.; Samarabandu, J.; Krasinski, A.; Parraga, G.; Fenster, A.

    2011-03-01

    Three-dimensional ultrasound (3D US) vessel wall volume (VWV) measurements provide high measurement sensitivity and reproducibility for the monitoring and assessment of carotid atherosclerosis. In this paper, we describe a semiautomated approach based on the level set method to delineate the media-adventitia and lumen boundaries of the common carotid artery from 3D US images to support the computation of VWV. Due to the presence of plaque and US image artifacts, the carotid arteries are challenging to segment using image information alone. Our segmentation framework combines several image cues with domain knowledge and limited user interaction. Our method was evaluated with respect to manually outlined boundaries on 430 2D US images extracted from 3D US images of 30 patients who have carotid stenosis of 60% or more. The VWV given by our method differed from that given by manual segmentation by 6.7% +/- 5.0%. For the media-adventitia and lumen segmentations, respectively, our method yielded Dice coefficients of 95.2% +/- 1.6%, 94.3% +/- 2.6%, mean absolute distances of 0.3 +/- 0.1 mm, 0.2 +/- 0.1 mm, maximum absolute distances of 0.8 +/- 0.4 mm, 0.6 +/- 0.3 mm, and volume differences of 4.2% +/- 3.1%, 3.4% +/- 2.6%. The realization of a semi-automated segmentation method will accelerate the translation of 3D carotid US to clinical care for the rapid, non-invasive, and economical monitoring of atherosclerotic disease progression and regression during therapy.

  14. Heavy wall pressure vessels for energy systems

    International Nuclear Information System (INIS)

    Canonico, D.A.

    Modifications of steels currently accepted in the Code appear to provide improved mechanical properties. These steels may permit the fabrication of larger diameter vessels with thinner section sizes and improved reliability and integrity. Adapting current specifications should expedite Code approval. Finally the challenge of improving welding procedures and adapting processes for field applications will result in higher quality weldments

  15. Atherosclerosis of coronary blood vessels - local or systemic inflamation?

    Science.gov (United States)

    Pejkov, Hristo; Kedev, Sasko; Panov, Saso; Srbinovska-Kostovska, Elizabeta; Lang, Irene

    2013-01-01

    The presence of atherosclerotic lesions in the blood vessels is a predisposition for the development and occurrence of acute ischaemic attacks. Bigger atherosclerotic lesions in the coronary blood vessels cause lumen occlusion, which is a cause of acute myocardial infarction. Endothelial dysfunction is defined as an ability of the endothelium to produce vasorelaxing nitric oxide (NO), or deregulation of the other vasoactive substances, such as angiotensin II and endothelin [13]. This definition describes endothelial dysfunction as an improper vasomotor constriction of the vessel, that leads to lumen occlusion of the already existing atherosclerotic lesions. According to the modern model, the development of atherosclerotic plaque and inappropriate endothelial NO production have a synergistic role in patho-physiological and molecular processes in the blood vessels [14]. Lesions in the coronary arteries are deposits of huge quantities of foamy cells and fibrous plaques. The thin fibrous plaques are 10-20% of the total plaque population and are the cause of 80-90% of clinical cases due to their ability to rupture [48]. According to all the results from published studies by far, it has been pointed out that the plaque stability, not the absolute size influences the rupture potential. Elucidating the risk factors that may modify in the atherogenesis and the consequent atherothrombic effect is the first step to this goal.

  16. Diameters of classes of smooth functions

    Science.gov (United States)

    Kudryavtsev, S. N.

    1995-08-01

    We describe the weak asymptotic behaviour of diameters of n-th order of the unit ball of W_p^l H^\\omega (I^d) in L_q(I^d), where I=(0,1), in dependence on n. Namely we consider the Kolmogorov diameter, the Gel'fand diameter, the linear diameter, the Aleksandrov diameter and the entropy diameter.

  17. Keeping control when cutting through a reactor vessel

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    UK Robotics' Advanced Teleoperation Controller (ATC) is a key component of one of the most extensive remote handling operations currently being undertaken - the removal of 165 mm diameter, 90 mm thick samples of carbon-manganese steel from the base of the Trawsfyndd reactor pressure vessel. These will then be used to assess the material properties of the vessel welds. (author)

  18. Determination of the critical buckling pressure of blood vessels using the energy approach.

    Science.gov (United States)

    Han, Hai-Chao

    2011-03-01

    The stability of blood vessels under lumen blood pressure is essential to the maintenance of normal vascular function. Differential buckling equations have been established recently for linear and nonlinear elastic artery models. However, the strain energy in bent buckling and the corresponding energy method have not been investigated for blood vessels under lumen pressure. The purpose of this study was to establish the energy equation for blood vessel buckling under internal pressure. A buckling equation was established to determine the critical pressure based on the potential energy. The critical pressures of blood vessels with small tapering along their axis were estimated using the energy approach. It was demonstrated that the energy approach yields both the same differential equation and critical pressure for cylindrical blood vessel buckling as obtained previously using the adjacent equilibrium approach. Tapering reduced the critical pressure of blood vessels compared to the cylindrical ones. This energy approach provides a useful tool for studying blood vessel buckling and will be useful in dealing with various imperfections of the vessel wall.

  19. BY FRUSTUM CONFINING VESSEL

    Directory of Open Access Journals (Sweden)

    Javad Khazaei

    2016-09-01

    Full Text Available Helical piles are environmentally friendly and economical deep foundations that, due to environmental considerations, are excellent additions to a variety of deep foundation alternatives available to the practitioner. Helical piles performance depends on soil properties, the pile geometry and soil-pile interaction. Helical piles can be a proper alternative in sensitive environmental sites if their bearing capacity is sufficient to support applied loads. The failure capacity of helical piles in this study was measured via an experimental research program that was carried out by Frustum Confining Vessel (FCV. FCV is a frustum chamber by approximately linear increase in vertical and lateral stresses along depth from top to bottom. Due to special geometry and applied bottom pressure, this apparatus is a proper choice to test small model piles which can simulate field stress conditions. Small scale helical piles are made with either single helix or more helixes and installed in fine grained sand with three various densities. Axial loading tests including compression and tension tests were performed to achieve pile ultimate capacity. The results indicate the helical piles behavior depends essentially on pile geometric characteristics, i.e. helix configuration and soil properties. According to the achievements, axial uplift capacity of helical model piles is about equal to usual steel model piles that have the helixes diameter. Helical pile compression bearing capacity is too sufficient to act as a medium pile, thus it can be substituted other piles in special geoenvironmental conditions. The bearing capacity also depends on spacing ratio, S/D, and helixes diameter.

  20. Afadin orients cell division to position the tubule lumen in developing renal tubules.

    Science.gov (United States)

    Gao, Lei; Yang, Zhufeng; Hiremath, Chitkale; Zimmerman, Susan E; Long, Blake; Brakeman, Paul R; Mostov, Keith E; Bryant, David M; Luby-Phelps, Katherine; Marciano, Denise K

    2017-10-01

    In many types of tubules, continuity of the lumen is paramount to tubular function, yet how tubules generate lumen continuity in vivo is not known. We recently found that the F-actin-binding protein afadin is required for lumen continuity in developing renal tubules, though its mechanism of action remains unknown. Here, we demonstrate that afadin is required for lumen continuity by orienting the mitotic spindle during cell division. Using an in vitro 3D cyst model, we find that afadin localizes to the cell cortex adjacent to the spindle poles and orients the mitotic spindle. In tubules, cell division may be oriented relative to two axes: longitudinal and apical-basal. Unexpectedly, in vivo examination of early-stage developing nephron tubules reveals that cell division is not oriented in the longitudinal (or planar-polarized) axis. However, cell division is oriented perpendicular to the apical-basal axis. Absence of afadin in vivo leads to misorientation of apical-basal cell division in nephron tubules. Together, these results support a model whereby afadin determines lumen placement by directing apical-basal spindle orientation, resulting in a continuous lumen and normal tubule morphogenesis. © 2017. Published by The Company of Biologists Ltd.

  1. Influence of inspiration level on bronchial lumen measurements with computed tomography.

    Science.gov (United States)

    Bakker, M Els; Stolk, Jan; Reiber, Johan H C; Stoel, Berend C

    2012-05-01

    Bronchial dimensions measured in CT images generally do not take inspiration level into consideration. However, some studies showed that the bronchial membrane is distensible with airway inflation. Therefore, re-examination of the elasticity of bronchi is needed. To assess the influence of respiration on bronchial lumen area (defined as distensibility) in different segmental bronchi and to explore the correlations between distensibility and both lung function and emphysema severity. In 44 subjects with COPD related to alpha-1-antitrypsin deficiency (AATD), bronchial lumen area was measured in CT images, acquired at different inspiration levels. Measurements were done at matched locations in one apical and two basal segmental airways (RB1, RB10 and LB10). Airway distensibility was calculated as lumen area difference divided by lung volume difference. Bronchial lumen area in the lower lobes (RB10 and LB10) correlated positively with FEV(1)%predicted (p=0.027 for RB10; and p=0.037 for LB10, respectively). Lumen area is influenced by respiration (p=0.006, p=0.045, and, p=0.005 for RB1, RB10 and LB10, respectively). Airway distensibility was different between upper and lower bronchi (pinspiration level and this distensibility is different between bronchi in the upper and lower lobes. Therefore, changes in lumen area over time should be studied whilst accounting for the lung volume changes, in order to estimate the progression of bronchial disease while excluding the effects of hyperinflation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Conduit diameter and wall remodeling in elite athletes and spinal cord injury.

    Science.gov (United States)

    Rowley, Nicola Jayne; Dawson, Ellen Adele; Hopman, Maria T E; George, Keith P; Whyte, Greg P; Thijssen, Dick H J; Green, Daniel John

    2012-05-01

    This study aimed to investigate localized and systemic effects of chronic exercise and inactivity on conduit artery remodeling in humans. We recruited elite athletes engaged in predominantly lower limb (LL runners/cyclists, n = 10) or upper limb (UL canoe paddlers, n = 12) exercise and matched able-bodied, recreationally active, controls (C, n = 16). We also studied wheelchair controls (spinal cord injury, n = 9) and athletes (spinal cord injury, n = 1; spina bifida, n = 4). Carotid, brachial, and superficial femoral (SF) artery diameter and wall thickness were assessed using high-resolution ultrasound. Brachial diameters were significantly larger in UL and wheelchair users (athletes and controls) compared with C (both P athletes having significantly greater lumen diameter than controls (both P athletes compared with C, including wheelchair athletes compared with wheelchair controls (P athletes and higher in wheelchair controls compared with able-bodied controls (P athletes demonstrated lower wall-to-lumen-ratio than less active wheelchair controls and able-bodied controls (P < 0.001). These findings suggest that remodeling of the arterial wall occurs systemically in response to exercise training and is unrelated to exercise type in humans. Conversely, localized effects are evident with respect to the effect of exercise on arterial diameter. These findings have implications for our understanding of the effects of exercise on arterial structure and function in humans.

  3. Absorbed dose calculations to blood and blood vessels for internally deposited radionuclides

    International Nuclear Information System (INIS)

    Akabani, G.; Poston, J.W. Sr.

    1992-01-01

    At present, absorbed dose calculations for radionuclides in the human circulatory system use relatively simple models and are restricted in their applications. To determine absorbed doses to the blood and to the surface of the blood vessel wall, Monte Carlo calculations were performed using the code Electron Gamma Shower (EGS4). Absorbed doses were calculated for the blood and the blood vessel wall (lumen) for different blood vessel sizes. The radionuclides chosen for this study were those commonly used in nuclear medicine. No diffusion of the radionuclide into the blood vessel was or cross fire between blood vessels was assumed. Results are useful in assessing the doses to blood and blood vessel walls for different nuclear medicine procedures

  4. Absorbed dose calculations to blood and blood vessels for internally deposited radionuclides

    International Nuclear Information System (INIS)

    Akabani, G.; Poston, J.W.

    1991-05-01

    At present, absorbed dose calculations for radionuclides in the human circulatory system used relatively simple models and are restricted in their applications. To determine absorbed doses to the blood and to the surface of the blood vessel wall, EGS4 Monte Carlo calculations were performed. Absorbed doses were calculated for the blood and the blood vessel wall (lumen) for different blood vessels sizes. The radionuclides chosen for this study were those commonly used in nuclear medicine. No diffusion of the radionuclide into the blood vessel was assumed nor cross fire between vessel was assumed. Results are useful in assessing the dose in blood and blood vessel walls for different nuclear medicine procedures. 6 refs., 6 figs., 5 tabs

  5. Improvement to reactor vessel

    International Nuclear Information System (INIS)

    1974-01-01

    The vessel described includes a prestressed concrete vessel containing a chamber and a removable cover closing this chamber. The cover is in concrete and is kept in its closed position by main and auxiliary retainers, comprising fittings integral with the concrete of the vessel. The auxiliary retainers pass through the concrete of the cover. This improvement may be applied to BWR, PWR and LMFBR type reactor vessel [fr

  6. Long-term lumen depreciation behavior and failure modes of multi-die array LEDs

    Science.gov (United States)

    Jayawardena, Asiri; Marcus, Daniel; Prugue, Ximena; Narendran, Nadarajah

    2013-09-01

    One of the main advantages of multi-die array light-emitting diodes (LEDs) is their high flux density. However, a challenge for using such a product in lighting fixture applications is the heat density and the need for thermal management to keep the junction temperatures of all the dies low for long-term reliable performance. Ten multi-die LED array samples for each product from four different manufacturers were subjected to lumen maintenance testing (as described in IES-LM-80-08), and their resulting lumen depreciation and failure modes were studied. The products were tested at the maximum case (or pin) temperature reported by the respective manufacturer by appropriately powering the LEDs. In addition, three samples for each product from two different manufacturers were subjected to rapid thermal cycling, and the resulting lumen depreciation and failure modes were studied. The results showed that the exponential lumen decay model using long-term lumen maintenance data as recommended in IES TM-21 does not fit for all package types. The failure of a string of dies and single die failure in a string were observed in some of the packages.

  7. ALICE HMPID Radiator Vessel

    CERN Multimedia

    2003-01-01

    View of the radiator vessels of the ALICE/HMPID mounted on the support frame. Each HMPID module is equipped with 3 indipendent radiator vessels made out of neoceram and fused silica (quartz) windows glued together. The spacers inside the vessel are needed to stand the hydrostatic pressure. http://alice-hmpid.web.cern.ch/alice-hmpid

  8. Targeted True Lumen Re-Entry With the Outback Catheter: Accuracy, Success, and Complications in 100 Peripheral Chronic Total Occlusions and Systematic Review of the Literature.

    Science.gov (United States)

    Kitrou, Panagiotis; Parthipun, Aneeta; Diamantopoulos, Athanasios; Paraskevopoulos, Ioannis; Karunanithy, Narayan; Katsanos, Konstantinos

    2015-08-01

    To report a single-center experience with the Outback re-entry device for targeted distal true lumen re-entry during subintimal recanalization of chronic total occlusions (CTOs) and compare the results with a systematic review of the literature. Between February 2011 and July 2013, 104 Outback devices were employed in 91 patients (mean age 64±9 years; 57 men) for subintimal recanalization of 100 vessels with CTOs after initial failure of spontaneous reentry. Fifty-two cases involved a retrograde approach to aortoiliac occlusions and 48 were re-entry attempts in infrainguinal CTOs. Outcome measures included complications and technical success, defined as successful targeted re-entry at the preplanned site of the distal true lumen. To evaluate device accuracy, the re-entry distance (between the point of true vessel reconstitution and the eventual re-entry point) was measured. Outback success was 93% (93/100); only 7 cases failed owing to heavy calcification (5/52 aortoiliac vs 2/48 infrainguinal, p=0.44). Re-entry was highly accurate, with a re-entry distance of ~1 cm in both subgroups (1.2±0.1 cm in aortoiliac vs 1.3±0.1 cm in infrainguinal, p=0.40). There were no major and 17 minor complications (9/52 aortoiliac vs 8/48 infrainguinal, p=0.93). Results are in line with the systematic review that identified 11 studies (only 1 randomized trial) involving mostly the femoropopliteal segment (119 aortoiliac and 464 infrainguinal segments). The pooled Outback success rate was 90% (95% confidence interval 85% to 94%) and the pooled complication rate was 4.3% (95% confidence interval 1.6% to 8.3%). The Outback device is safe and has a very high rate of achieving targeted true lumen re-entry, which minimizes the sacrifice of healthy vessel in the aortoiliac and infrainguinal arteries. © The Author(s) 2015.

  9. Automatic Lumen Detection on Longitudinal Ultrasound B-Mode Images of the Carotid Using Phase Symmetry

    Directory of Open Access Journals (Sweden)

    José Rouco

    2016-03-01

    Full Text Available This article describes a method that improves the performance of previous approaches for the automatic detection of the common carotid artery (CCA lumen centerline on longitudinal B-mode ultrasound images. We propose to detect several lumen centerline candidates using local symmetry analysis based on local phase information of dark structures at an appropriate scale. These candidates are analyzed with selection mechanisms that use symmetry, contrast or intensity features in combination with position-based heuristics. Several experimental results are provided to evaluate the robustness and performance of the proposed method in comparison with previous approaches. These results lead to the conclusion that our proposal is robust to noise, lumen artifacts, contrast variations and that is able to deal with the presence of CCA-like structures, significantly improving the performance of our previous approach, from 87.5% ± 0.7% of correct detections to 98.3% ± 0.3% in a set of 200 images.

  10. Activated host neutrophils in the larval midgut lumen of the human bot fly Dermatobia hominis.

    Science.gov (United States)

    Leite, Antônio C R; Evangelista, L G

    2002-04-01

    Light microscopy (LM) and transmission electron microscopy (TEM) were used to observe activated polymorphonuclear neutrophils from mammalian hosts as well as invading bacteria in the midgut lumen of larvae of the human bot fly Dermatobia hominis. Other resident or recruited cells associated with dermal myiasis were fed on by larvae and digested more rapidly than neutrophils. The latter were observed moving towards bacteria and particles of food, extending the filopodia and engulfing material to be digested within phagosomes. The larval midgut lumen, thus, appears to be a suitable environment to produce neutrophil activation at least for short periods, as seen in mammalian hosts. Although interactions between phagocytes and bacteria in the midgut lumen may be important in bot fly larval development, further studies are required to confirm this.

  11. Blood vessels pattern heparan sulfate gradients between their apical and basolateral aspects.

    Directory of Open Access Journals (Sweden)

    Liat Stoler-Barak

    Full Text Available A hallmark of immune cell trafficking is directional guidance via gradients of soluble or surface bound chemokines. Vascular endothelial cells produce, transport and deposit either their own chemokines or chemokines produced by the underlying stroma. Endothelial heparan sulfate (HS was suggested to be a critical scaffold for these chemokine pools, but it is unclear how steep chemokine gradients are sustained between the lumenal and ablumenal aspects of blood vessels. Addressing this question by semi-quantitative immunostaining of HS moieties around blood vessels with a pan anti-HS IgM mAb, we found a striking HS enrichment in the basal lamina of resting and inflamed post capillary skin venules, as well as in high endothelial venules (HEVs of lymph nodes. Staining of skin vessels with a glycocalyx probe further suggested that their lumenal glycocalyx contains much lower HS density than their basolateral extracellular matrix (ECM. This polarized HS pattern was observed also in isolated resting and inflamed microvascular dermal cells. Notably, progressive skin inflammation resulted in massive ECM deposition and in further HS enrichment around skin post capillary venules and their associated pericytes. Inflammation-dependent HS enrichment was not compromised in mice deficient in the main HS degrading enzyme, heparanase. Our results suggest that the blood vasculature patterns steep gradients of HS scaffolds between their lumenal and basolateral endothelial aspects, and that inflammatory processes can further enrich the HS content nearby inflamed vessels. We propose that chemokine gradients between the lumenal and ablumenal sides of vessels could be favored by these sharp HS scaffold gradients.

  12. A new evaluation of the upper esophageal sphincter using the functional lumen imaging probe: a preliminary report.

    LENUS (Irish Health Repository)

    Regan, J

    2012-03-06

    Objective and reliable evaluation of upper esophageal sphincter (UES) opening during swallowing based on videofluoroscopy and pharyngeal manometry challenges dysphagia clinicians. The functional lumen imaging probe (FLIP) is a portable tool based on impedance planimetry originally designed to measure esophogastric junction compliance. It is hypothesized that FLIP can evaluate UES distensibility, and can provide UES diameter and pressure measurements at rest, during swallowing, and during voluntary maneuvers. Eleven healthy adult subjects consented to FLIP evaluation. The probe was inserted transorally, and the balloon was positioned across the UES. Two 20-mL ramp distensions were completed. Changes in UES diameter and intraballoon pressure were measured during dry and 5-mL liquid swallows, and during voluntary swallow postures and maneuvers employed in clinical practice. The protocol was completed by 10 of 11 healthy subjects. Mean intraballoon pressure increased throughout 5-mL (5.8 mmHg; -4.5-18.6 mmHg), 10-mL (8.7 mmHg; 2.3-28.5 mmHg), 15-mL (17.3 mmHg; 9.5-34.8 mmHg), and 20-mL (31.2 mmHg; 16-46.3 mmHg) balloon volumes. Mean resting UES diameter (4.9 mm) increased during dry swallows (9.2 mm) and 5-mL liquid swallows (7.7 mm). Mean UES diameter increased during 5-mL liquid swallows with head turn to right (8.1 mm) and left (8.3 mm), chin tuck (8.4 mm), effortful swallow (8.5 mm), Mendelsohn maneuver (8.1 mm), and supraglottic swallow (7.8 mm). FLIP was safely inserted and distended in the UES, and provided useful quantitative data regarding UES distensibility and UES diameter changes during swallowing maneuvers. Further research is being conducted to explore the role of FLIP in UES evaluation.

  13. Light induced changes in protein expression and uniform regulation of transcription in the thylakoid lumen of Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Irene Granlund

    Full Text Available In plants oxygenic photosynthesis is performed by large protein complexes found in the thylakoid membranes of chloroplasts. The soluble thylakoid lumen space is a narrow and compressed region within the thylakoid membrane which contains 80-200 proteins. Because the thylakoid lumen proteins are in close proximity to the protein complexes of photosynthesis, it is reasonable to assume that the lumen proteins are highly influenced by the presence of light. To identify light regulated proteins in the thylakoid lumen of Arabidopsis thaliana we developed a faster thylakoid preparation and combined this with difference gel electrophoresis (DIGE of dark-adapted and light-adapted lumen proteomes. The DIGE experiments revealed that 19 lumen proteins exhibit increased relative protein levels after eight hour light exposure. Among the proteins showing increased abundance were the PsbP and PsbQ subunits of Photosystem II, major plastocyanin and several other proteins of known or unknown function. In addition, co-expression analysis of publicly available transcriptomic data showed that the co-regulation of lumen protein expression is not limited to light but rather that lumen protein genes exhibit a high uniformity of expression. The large proportion of thylakoid lumen proteins displaying increased abundance in light-adapted plants, taken together with the observed uniform regulation of transcription, implies that the majority of thylakoid lumen proteins have functions that are related to photosynthetic activity. This is the first time that an analysis of the differences in protein level during a normal day/night cycle has been performed and it shows that even a normal cycle of light significantly influences the thylakoid lumen proteome. In this study we also show for the first time, using co-expression analysis, that the prevalent lumenal chloroplast proteins are very similarly regulated at the level of transcription.

  14. Confinement Vessel Assay System: Calibration and Certification Report

    Energy Technology Data Exchange (ETDEWEB)

    Frame, Katherine C. [Los Alamos National Laboratory; Bourne, Mark M. [Los Alamos National Laboratory; Crooks, William J. [Los Alamos National Laboratory; Evans, Louise [Los Alamos National Laboratory; Gomez, Cipriano [Retired CMR-OPS: OPERATIONS; Mayo, Douglas R. [Los Alamos National Laboratory; Miko, David K. [Los Alamos National Laboratory; Salazar, William R. [Los Alamos National Laboratory; Stange, Sy [Los Alamos National Laboratory; Vigil, Georgiana M. [Los Alamos National Laboratory

    2012-07-17

    Los Alamos National Laboratory has a number of spherical confinement vessels (CVs) remaining from tests involving nuclear materials. These vessels have an inner diameter of 6 feet with 1 to 2 inch thick steel walls. The goal of the Confinement Vessel Disposition (CVD) project is to remove debris and reduce contamination inside the vessels. The Confinement Vessel Assay System (CVAS) was developed to measure the amount of SNM in CVs before and after cleanout. Prior to cleanout, the system will be used to perform a verification measurement of each vessel. After cleanout, the system will be used to perform safeguards-quality assays of {le} 100-g {sup 239}Pu equivalent in a vessel for safeguards termination. The system was calibrated in three different mass regions (low, medium, and high) to cover the entire plutonium mass range that will be assayed. The low mass calibration and medium mass calibration were verified for material positioned in the center of an empty vessel. The systematic uncertainty due to position bias was estimated using an MCNPX model to simulate the response of the system to material localized at various points along the inner surface of the vessel. The background component due to cosmic ray spallation was determined by performing measurements of an empty vessel and comparing to measurements in the same location with no vessel present. The CVAS has been tested and calibrated in preparation for verification and safeguards measurements of CVs before and after cleanout.

  15. CT study of branching characters of pulmonary small vessels

    International Nuclear Information System (INIS)

    Wang Lihua; Li Runming; Guo Yuomin; Yang Jian; Niu Gang; Liu Jihan

    2003-01-01

    Objective: To study the branching geometry of the pulmonary small vessels in vivo by using imaging and branching geometrical methods, and to explore the branching configuration of pulmonary vessels. Methods: 2008 sets of dichotomous small pulmonary vessels were measured in chest helical CT of 63 normal cases. The expansion and asymmetrical factors were calculated, and their characteristics and correlation with the mother branches were studied. Results: The two factors in vivo had significant differences and different trends compared with those in the specimens; the average of the expansion factor was 1.0022, there was negative linear correlation between the diameter of mother branches. The asymmetrical factor had the median of 1.4938, there was a positive linear correlation between this factor and the diameter of mother branches, and this trend was most apparent when the diameter of mother branch was blow 4 mm. The asymmetrical factor became not evident when the diameter of mother branch was above 6.0 mm. when the diameter of mother branch was equal to 2.5 mm, the expansion factor quickly increased to 1.622 and the asymmetrical factor decreased to about 1.500. Conclusion: The study of the branching character of the pulmonary small vessels by using branching geometry method not only contributed to realize the configuration and distribution characters of pulmonary vessels but also had potential theoretical and practical value in setting up the mathematic and physical model of blood stream and pressure

  16. Personal experiences in direct ultrasound-guided injection of thrombin into the lumen of pseudoaneurysm as a method of treatment in case of iatrogenic femoral artery damage

    International Nuclear Information System (INIS)

    Slonina, J.; Zaleska-Dorobisz, U.; Malczewska, J.; Kozminska, U.; Sasiadek, M.; Obremska, M.; Agrawal, A.

    2010-01-01

    Background: Pseudoaneurysms constitute a quite common complication of procedures requiring puncture of the common femoral artery. The risk factors of the condition include: obesity, arterial hypertension, sex (more prevalent in males) as well as antithrombotic therapy. Material/Methods: The US-guided injection of thrombin into the pseudoaneurysm lumen was performed in patients referred from the Department of Invasive Cardiology who had undergone coronarography or coronary angioplasty. Pseudoaneurysms constituted the complication of common femoral artery canulation. After setting the diagnosis of pseudoaneurysm by means of Doppler ultrasound, patients with large pseudoaneurysms of volume exceeding 10 mm were qualified for thrombin injection. Generally, 33 patients underwent the treatment. In 3 cases - due to the presence of multiocular pseudoaneurysm - thrombin was administered twice. Results: Taking into account the safety of the procedure, ultimately 33 patients were qualified for thrombin administration, in whom aneurism of diameter exceeding 10 mm was diagnosed. In 3 patients with aneurysm of less than 10 mm, only a compression band was used prophylactically. In one case, because of a considerable oedema surrounding the tissue, as well as deep location of the aneurysm in the groin, thrombin treatment was not given due to technical reasons. In 30 cases, single administration of thrombin was effective and resulted in a complete thrombosis of the pseudoaneurism lumen within a couple of seconds following thrombin injection. In 3 patients with multicellular aneurysm, thrombin was given twice, resulting in a total obliteration of the pseudoaneurysm in two cases only. No complications were observed after the performed procedures. No recanalisation of pseudoaneurysms was demonstrated in follow-up examinations. Conclusions: 1. Direct thrombin injection into the pseudoaneurysm lumen can constitute an alternative method of treatment for open surgical techniques. 2. The

  17. Personal experiences in direct ultrasound-guided injection of thrombin into the lumen of pseudoaneurysm as a method of treatment in case of iatrogenic femoral artery damage

    International Nuclear Information System (INIS)

    Słonina, Joanna; Obremska, Marta; Zaleska-Dorobisz, Urszula; Agrawal, Anil; Malczewska, Joanna; Koźmińska, Urszula; Sąsiadek, Marek

    2010-01-01

    Pseudoaneurysms constitute a quite common complication of procedures requiring puncture of the common femoral artery. The risk factors of the condition include: obesity, arterial hypertension, sex (more prevalent in males) as well as antithrombotic therapy. The US-guided injection of thrombin into the pseudoaneurysm lumen was performed in patients referred from the Department of Invasive Cardiology who had undergone coronarography or coronary angioplasty. Pseudoaneurysms constituted the complication of common femoral artery canulation. After setting the diagnosis of pseudoaneurysm by means of Doppler ultrasound, patients with large pseudoaneurysms of volume exceeding 10 mm were qualified for thrombin injection. Generally, 33 patients underwent the treatment. In 3 cases – due to the presence of multiocular pseudoaneurysm – thrombin was administered twice. Taking into account the safety of the procedure, ultimately 33 patients were qualified for thrombin administration, in whom aneurism of diameter exceeding 10 mm was diagnosed. In 3 patients with aneurysm of less than 10mm, only a compression band was used prophylactically. In one case, because of a considerable oedema surrounding the tissue, as well as deep location of the aneurysm in the groin, thrombin treatment was not given due to technical reasons. In 30 cases, single administration of thrombin was effective and resulted in a complete thrombosis of the pseudoaneurism lumen within a couple of seconds following thrombin injection. In 3 patients with multicellular aneurysm, thrombin was given twice, resulting in a total obliteration of the pseudoaneurysm in two cases only. No complications were observed after the performed procedures. No recanalisation of pseudoaneurysms was demonstrated in follow-up examinations. 1. Direct thrombin injection into the pseudoaneurysm lumen can constitute an alternative method of treatment for open surgical techniques. 2. The procedure is highly effective, cheap and minimally

  18. Pressure vessel design manual

    CERN Document Server

    Moss, Dennis R

    2013-01-01

    Pressure vessels are closed containers designed to hold gases or liquids at a pressure substantially different from the ambient pressure. They have a variety of applications in industry, including in oil refineries, nuclear reactors, vehicle airbrake reservoirs, and more. The pressure differential with such vessels is dangerous, and due to the risk of accident and fatality around their use, the design, manufacture, operation and inspection of pressure vessels is regulated by engineering authorities and guided by legal codes and standards. Pressure Vessel Design Manual is a solutions-focused guide to the many problems and technical challenges involved in the design of pressure vessels to match stringent standards and codes. It brings together otherwise scattered information and explanations into one easy-to-use resource to minimize research and take readers from problem to solution in the most direct manner possible. * Covers almost all problems that a working pressure vessel designer can expect to face, with ...

  19. An artificial neural network method for lumen and media-adventitia border detection in IVUS.

    Science.gov (United States)

    Su, Shengran; Hu, Zhenghui; Lin, Qiang; Hau, William Kongto; Gao, Zhifan; Zhang, Heye

    2017-04-01

    Intravascular ultrasound (IVUS) has been well recognized as one powerful imaging technique to evaluate the stenosis inside the coronary arteries. The detection of lumen border and media-adventitia (MA) border in IVUS images is the key procedure to determine the plaque burden inside the coronary arteries, but this detection could be burdensome to the doctor because of large volume of the IVUS images. In this paper, we use the artificial neural network (ANN) method as the feature learning algorithm for the detection of the lumen and MA borders in IVUS images. Two types of imaging information including spatial, neighboring features were used as the input data to the ANN method, and then the different vascular layers were distinguished accordingly through two sparse auto-encoders and one softmax classifier. Another ANN was used to optimize the result of the first network. In the end, the active contour model was applied to smooth the lumen and MA borders detected by the ANN method. The performance of our approach was compared with the manual drawing method performed by two IVUS experts on 461 IVUS images from four subjects. Results showed that our approach had a high correlation and good agreement with the manual drawing results. The detection error of the ANN method close to the error between two groups of manual drawing result. All these results indicated that our proposed approach could efficiently and accurately handle the detection of lumen and MA borders in the IVUS images. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Minimization of lumen depreciation in LED lamps using thermal transient behavior analysis and design optimizations.

    Science.gov (United States)

    Khan, M Nisa

    2016-02-10

    We expansively investigate thermal behaviors of various general-purpose light-emitting diode (LED) lamps and apply our measured results, validated by simulation, to establish lamp design rules for optimizing their optical and thermal properties. These design rules provide the means to minimize lumen depreciation over time by minimizing the periods for lamps to reach thermal steady-state while maintaining their high luminous efficacy and omnidirectional light distribution capability. While it is well known that minimizing the junction temperature of an LED leads to a longer lifetime and an increased lumen output, our study demonstrates, for the first time, to the best of our knowledge, that it is also important to minimize the time it takes to reach thermal equilibrium because doing so minimizes lumen depreciation and enhances light output and color stability during operation. Specifically, we have found that, in addition to inadequate heat-sink fin areas for a lamp configuration, LEDs mounted on multiple boards, as opposed to a single board, lead to longer periods for reaching thermal equilibrium contributing to larger lumen depreciation.

  1. Pressure-Guided Positioning of Bicaval Dual-Lumen Catheters for Venovenous Extracorporeal Gas Exchange

    Science.gov (United States)

    2013-01-01

    using a bicaval dual-lumen catheter in neonates . J Pediatr Surg 47:430–434 3. Turner DA, Cheifetz IM, Rehder KJ, Williford WL, Bonadonna D, Banuelos SJ...Defreyne L, Benoit DD, Decruyenaere J (2011) Epidemiology of contrast-associated acute kidney injury in ICU patients: a retrospective cohort analysis

  2. Fate of the dissecting lumen by CT study following surgical repair

    International Nuclear Information System (INIS)

    Nakajima, Nobuyuki; Ando, Taizo; Kawazoe, Kohei; Tomino, Tetsuo; Fujita, Takeshi; Naito, Hiroaki; Yamaguchi, Toshio.

    1983-01-01

    A postoperative follow-up study on the fate of dissecting lumen by mean of computer tomography has been evaluated. The materials were 21 patients who underwent surgery for dissection of the aorta, including 8 patients in type 1 of DeBakey classification, 3 in type 11, 8 in type 111 and 2 patients of localized dissection in descending and abdominal aorta. The susceptibility for thrombus formation in dissecting lumen appeared to be relating to the background etiology of dissection where poor tendency for thrombus formation was observed in group of patients with Marfan syndrome and its' incomplete form. On the other hand in those group of patients who had a history of hypertension and atherosclerosis probable, a strong tendency of thrombus formation and eventual occlusion of lumen was obtained. On the basis of above findings, it will be said that the surgical intervention for type 1 of DeBakey classification in Marfan patient is merely creating type 111 dissection, closed observation in the future change of dissecting lumen is utmost important especially in those group of patients. (author)

  3. Lumen degradation analysis of LED lamps based on the subsystem isolation method.

    Science.gov (United States)

    Ke, Hong-Liang; Hao, Jian; Tu, Jian-Hui; Miao, Pei-Xian; Wang, Chao-Quan; Cui, Jing-Zhong; Sun, Qiang; Sun, Ren-Tao

    2018-02-01

    The lumen degradation of LED lamps undergoing an accelerated aging test is investigated. The entire LED lamp is divided into three subsystems, namely, driver, lampshade, and LED light source. The parameters of output power [Watts (W)], transmittance (%), and lumen flux (lm) are adopted in the analysis of the degradation of the driver, lampshade, and LED light source, respectively. Two groups of LED lamps are aged under the ambient temperatures of 25°C and 85°C, respectively, with the aging time of 2000 h. The lumen degradation of the lamps is from 3.8% to 4.9% for the group under a temperature of 25°C and from 10.6% to 12.7% for the group under a temperature of 85°C. The LED light source is the most aggressive part of the three subsystems, which accounts for 70.5% of the lumen degradation of the LED lamp on average. The lampshade is the second degradation source, which causes 21.5% of the total amount on average. The driver is the third degradation source, which causes 6.5% under 25°C and 2.8% under 85°C of the total amount on average.

  4. FACTORS AND COMPLICATIONS AFFECTING CATHETER AND TECHNIQUE SURVIVAL WITH PERMANENT SINGLE-LUMEN DIALYSIS CATHETERS

    NARCIS (Netherlands)

    DEMEESTER, J; VANHOLDER, R; DEROOSE, J; RINGOIR, S

    1994-01-01

    This long-term study on the outcome of permanent silicone single-lumen dialysis catheters consisted of 43 surgically inserted catheters in 33 patients. All catheters were attached to a pressure-pressure single-cannula dialysis system. Technique and catheter survival were 80 and 59% at 1 year, and 63

  5. Lumen-based detection of prostate cancer via convolutional neural networks

    Science.gov (United States)

    Kwak, Jin Tae; Hewitt, Stephen M.

    2017-03-01

    We present a deep learning approach for detecting prostate cancers. The approach consists of two steps. In the first step, we perform tissue segmentation that identifies lumens within digitized prostate tissue specimen images. Intensity- and texture-based image features are computed at five different scales, and a multiview boosting method is adopted to cooperatively combine the image features from differing scales and to identify lumens. In the second step, we utilize convolutional neural networks (CNN) to automatically extract high-level image features of lumens and to predict cancers. The segmented lumens are rescaled to reduce computational complexity and data augmentation by scaling, rotating, and flipping the rescaled image is applied to avoid overfitting. We evaluate the proposed method using two tissue microarrays (TMA) - TMA1 includes 162 tissue specimens (73 Benign and 89 Cancer) and TMA2 comprises 185 tissue specimens (70 Benign and 115 Cancer). In cross-validation on TMA1, the proposed method achieved an AUC of 0.95 (CI: 0.93-0.98). Trained on TMA1 and tested on TMA2, CNN obtained an AUC of 0.95 (CI: 0.92-0.98). This demonstrates that the proposed method can potentially improve prostate cancer pathology.

  6. Thrombosis caused by polyurethane double-lumen subclavian superior vena cava catheter and hemodialysis

    DEFF Research Database (Denmark)

    Wanscher, Maria Rørbæk; Frifelt, J J; Smith-Sivertsen, C

    1988-01-01

    During an 18-month period, 82 consecutive patients (37 women and 45 men), with a mean age of 50 yr (range 15 to 74), underwent hemodialysis with 91 polyurethane double-lumen subclavian superior vena cava catheters inserted via the right subclavian vein. Upon catheter removal, venograms were...

  7. The diagnostic value of cine-MR imaging in diseases of great vessels

    International Nuclear Information System (INIS)

    Sasaki, Shigeyuki; Yoshida, Hideaki; Matsui, Yoshiro; Sakuma, Makoto; Yasuda, Keihide; Tanabe, Tatsuzo; Chouji, H.

    1990-01-01

    The diagnostic value of cine magnetic resonance imaging (cine-MRI) was evaluated in 10 patients with diseases of great vessels. The parameters necessary to decide the appropriate treatment, such as presence and extension of intimal flap, DeBakey type classification, identification of the entry, differentiation between true and false lumen, and between thrombosis and slow flow were demonstrated in all patients with dissecting aortic aneurysm. However, abdominal aortic branches could not be demonstrated enough by cine-MRI, therefore conventional AOG was necessary to choose the operative procedure in these cases. In patients with thoracic aortic aneurysm (TAA), cine-MRI was valuable in demonstrating both blood flow and thrombus in the lumen of aneurysm, and AOG was thought to be unnecessary in most cases. Cine-MRI is a promising new technique for the evaluation of diseases of great vessels. (author)

  8. Small Vessel Security Strategy

    National Research Council Canada - National Science Library

    2008-01-01

    ...), narcotics, aliens, and other contraband, and other criminals. Small vessels have also been successfully employed overseas by terrorists to deliver Waterborne Improvised Explosive Devices (WBIEDs...

  9. Maury Journals - German Vessels

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — German vessels observations, after the 1853 Brussels Conference that set International Maritime Standards, modeled after Maury Marine Standard Observations.

  10. Nuclear reactor pressure vessel

    International Nuclear Information System (INIS)

    McDonald, B.N.

    1976-01-01

    In nuclear power reactor systems which have a reactor core inside a pressure vessel, the feedwater inlet pipe and steam discharge nozzle usually require separate pressure vessel penetrations. This requirement involves a great deal of expensive high quality special machining, welding and weld joint testing. The invention overcomes most of these problems by nestling the feedwater inlet pipe inside the steam discharge nozzle. At the same time the individual heat exchanger modules are supported from the pressure vessel at the same location as the nested feedwater inlet pipe and steam discharge nozzle combination, thus eliminating the need to accomodate troublesome differential thermal expansion problems through special structures within the pressure vessel

  11. The Prevalence of Sleep Apnea in Type B Aortic Dissection: Implications for False Lumen Thrombosis.

    Science.gov (United States)

    Wang, Ling; Chen, Jiyan; Li, Guangxi; Luo, Songyuan; Wang, Rui; Li, Wei; Zhang, Jiawei; Liu, Yuan; Huang, Wenhui; Cao, Yingshu; Zhou, Yingling; Chen, Pingyan; Pressman, Gregg S; Somers, Virend K; Luo, Jianfang

    2017-03-01

    Obstructive sleep apnea (OSA) has been implicated in aortic dissection. Thrombosis of the false lumen is associated with a prognosis of type B aortic dissection (AoD), and partial thrombosis has been reported to be an independent predictor of mortality. This study sought to explore whether the severity of OSA is associated with false lumen thrombosis. In this observational study, 151 type B AoD patients were recruited consecutively from 2013 to 2015. The status of the false lumen was classified as patent, partially thrombosed, or completely thrombosed based on a computer tomography angiography image. Patients were divided into non-OSA group (apnea-hypopnea index [AHI] 30) using the AHI. The prevalence of OSA in type B dissection was 66.2%. Among 151 cases, 51 patients (33.8%) were in the non-OSA group, 56 (37.1%) were in the mild group, 21 (13.9%) were in the moderate group, and 23 (15.2%) were in the severe group. Additionally, a partially thrombosed false lumen was observed in 88 patients (58.3%). Multivariable analysis revealed that OSA severity was positively associated with partial thrombosis (odds ratio, 1.784, 95% confidence interval: 1.182-2.691, P = .006) after adjusting for other confounding factors. OSA was present in two-thirds of patients with type B AoD. The severity of OSA was significantly associated with an increased risk of partial false lumen thrombosis. OSA may therefore be implicated in both the etiology and prognosis of AoD.

  12. Sonographic assessment of vessel invasion by cervical masses in dogs

    Directory of Open Access Journals (Sweden)

    C.F. Carvalho

    2012-10-01

    Full Text Available Tumor invasion of the vessels displays both therapeutic and prognostic implications and represents a challenge for head and neck surgeons. Although previous research has shown that ultrasound can detect such invasions, accurate sonographic parameters to do so have not yet been established. We sought to determine sonographic criteria which are able to characterize these invasions. A high-resolution transducer was used to perform ultrasound examinations of 15 patients selected from a group with inconclusive radiography and computed tomography diagnosis. We found that encasement of the vessel, tumor immobility or fixation in the vessel wall, and narrowing and/or deformity of the lumen were the best criteria. Indeed, when loss of hyperechoic interface of the vessel wall was used as a single criterion it generated false positive results. This study shows that a combination of parameters can be used to provide the best sensitivity and specificity values to produce conclusive diagnosis of vessel invasion by tumors in the cervical region.

  13. PRESSURE-RESISTANT VESSEL

    NARCIS (Netherlands)

    Beukers, A.; De Jong, T.

    1997-01-01

    Abstract of WO 9717570 (A1) The invention is directed to a wheel-shaped pressure-resistant vessel for gaseous, liquid or liquefied material having a substantially rigid shape, said vessel comprising a substantially continuous shell of a fiber-reinforced resin having a central opening, an inner

  14. Volumetric analysis demonstrates that true and false lumen remodeling persists for 12 months after thoracic endovascular aortic repair

    Directory of Open Access Journals (Sweden)

    Ga-Young Suh, PhD

    2016-09-01

    Full Text Available A 62-year-old man underwent an elephant trunk procedure followed by thoracic endovascular aortic repair (TEVAR. Computed tomography angiography-based models were built to quantify volume of the whole aorta and true and false lumens preoperatively, before TEVAR, after TEVAR, and at follow-up at 3, 6, and 12 months. With TEVAR, descending aortic true lumen volume increased by 54%, then increased additionally by 60% during 12 months. The descending aortic false lumen volume regressed continuously for 12 months following TEVAR, with the most rapid rate from 6 to 12 months at 16 cm3/month. TEVAR immediately increased true lumen volume and continued to remodel the true and false lumens throughout the following 12 months.

  15. A model for ultrasound contrast agent in a phantom vessel

    KAUST Repository

    Qamar, Adnan

    2014-02-01

    A theoretical framework to model the dynamics of Ultrasound Contrast Agent (UCA) inside a phantom vessel is presented. The model is derived from the reduced Navier-Stokes equation and is coupled with the evolving flow field solution inside the vessel by a similarity transformation approach. The results are computed, and compared with experiments available in literature, for the initial UCA radius of Ro=1.5 μm and 2 μm for the vessel diameter of D=12 μm and 200 μm with the acoustic parameters as utilized in the experiments. When compared to other models, better agreement on smaller vessel diameter is obtained with the proposed coupled model. The model also predicts, quite accurately, bubble fragmentation in terms of acoustic and geometric parameters. © 2014 IEEE.

  16. Defining an adequate sample of earlywood vessels for retrospective injury detection in diffuse-porous species.

    Directory of Open Access Journals (Sweden)

    Estelle Arbellay

    Full Text Available Vessels of broad-leaved trees have been analyzed to study how trees deal with various environmental factors. Cambial injury, in particular, has been reported to induce the formation of narrower conduits. Yet, little or no effort has been devoted to the elaboration of vessel sampling strategies for retrospective injury detection based on vessel lumen size reduction. To fill this methodological gap, four wounded individuals each of grey alder (Alnus incana (L. Moench and downy birch (Betula pubescens Ehrh. were harvested in an avalanche path. Earlywood vessel lumina were measured and compared for each tree between the injury ring built during the growing season following wounding and the control ring laid down the previous year. Measurements were performed along a 10 mm wide radial strip, located directly next to the injury. Specifically, this study aimed at (i investigating the intra-annual duration and local extension of vessel narrowing close to the wound margin and (ii identifying an adequate sample of earlywood vessels (number and intra-ring location of cells attesting to cambial injury. Based on the results of this study, we recommend analyzing at least 30 vessels in each ring. Within the 10 mm wide segment of the injury ring, wound-induced reduction in vessel lumen size did not fade with increasing radial and tangential distances, but we nevertheless advise favoring early earlywood vessels located closest to the injury. These findings, derived from two species widespread across subarctic, mountainous, and temperate regions, will assist retrospective injury detection in Alnus, Betula, and other diffuse-porous species as well as future related research on hydraulic implications after wounding.

  17. Small-Diameter PTFE Portosystemic Shunts: Portocaval vs Mesocaval

    Directory of Open Access Journals (Sweden)

    Robert Shields

    1998-01-01

    Full Text Available Fifty-seven patients with failed sclerotherapy received a mesocaval interposition shunt with an externally supported, ringed polytetrafluoroethylene prosthesis of either 10 or 12 mm diameter. Thirty-one patients had Child-Pugh gradeA disease and 26 grade B; all had a liver volume of 1000– 2500 ml. Follow-up ranged from 16 months to 6 years 3 months. Three patients (5 per cent died in the postoperative period. There were two postoperative recurrences of variceal haemorrhage and one recurrent bleed in the second year after surgery. The cumulative shunt patency rate was 95 per cent and the incidence of encephalopathy 9 per cent; the latter was successfully managed by protein restriction and/or lactulose therapy. The actuarial survival rate for the whole group at 6 years was 78 per cent, for those with Child-Pugh grade A 88 per cent and for grade B 67 per cent. Small-lumen mesocaval interposition shunting achieves portal decompression, preserves hepatopetal flow, has a low incidence of shunt thrombosis, prevents recurrent variceal bleeding and is not associated with significant postoperative encephalopathy.

  18. Containment vessel drain system

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Scott G.

    2018-01-30

    A system for draining a containment vessel may include a drain inlet located in a lower portion of the containment vessel. The containment vessel may be at least partially filled with a liquid, and the drain inlet may be located below a surface of the liquid. The system may further comprise an inlet located in an upper portion of the containment vessel. The inlet may be configured to insert pressurized gas into the containment vessel to form a pressurized region above the surface of the liquid, and the pressurized region may operate to apply a surface pressure that forces the liquid into the drain inlet. Additionally, a fluid separation device may be operatively connected to the drain inlet. The fluid separation device may be configured to separate the liquid from the pressurized gas that enters the drain inlet after the surface of the liquid falls below the drain inlet.

  19. Reactor vessel sealing plug

    International Nuclear Information System (INIS)

    Dooley, R.A.

    1986-01-01

    This invention relates to an apparatus and method for sealing the cold leg nozzles of a nuclear reactor pressure vessel from a remote location during maintenance and inspection of associated steam generators and pumps while the pressure vessel and refueling canal are filled with water. The apparatus includes a sealing plug for mechanically sealing the cold leg nozzle from the inside of a reactor pressure vessel. The sealing plugs include a primary and a secondary O-ring. An installation tool is suspended within the reactor vessel and carries the sealing plug. The tool telescopes to insert the sealing plug within the cold leg nozzle, and to subsequently remove the plug. Hydraulic means are used to activate the sealing plug, and support means serve to suspend the installation tool within the reactor vessel during installation and removal of the sealing plug

  20. Automated registration of multispectral MR vessel wall images of the carotid artery

    Energy Technology Data Exchange (ETDEWEB)

    Klooster, R. van ' t; Staring, M.; Reiber, J. H. C.; Lelieveldt, B. P. F.; Geest, R. J. van der, E-mail: rvdgeest@lumc.nl [Department of Radiology, Division of Image Processing, Leiden University Medical Center, 2300 RC Leiden (Netherlands); Klein, S. [Department of Radiology and Department of Medical Informatics, Biomedical Imaging Group Rotterdam, Erasmus MC, Rotterdam 3015 GE (Netherlands); Kwee, R. M.; Kooi, M. E. [Department of Radiology, Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht 6202 AZ (Netherlands)

    2013-12-15

    Purpose: Atherosclerosis is the primary cause of heart disease and stroke. The detailed assessment of atherosclerosis of the carotid artery requires high resolution imaging of the vessel wall using multiple MR sequences with different contrast weightings. These images allow manual or automated classification of plaque components inside the vessel wall. Automated classification requires all sequences to be in alignment, which is hampered by patient motion. In clinical practice, correction of this motion is performed manually. Previous studies applied automated image registration to correct for motion using only nondeformable transformation models and did not perform a detailed quantitative validation. The purpose of this study is to develop an automated accurate 3D registration method, and to extensively validate this method on a large set of patient data. In addition, the authors quantified patient motion during scanning to investigate the need for correction. Methods: MR imaging studies (1.5T, dedicated carotid surface coil, Philips) from 55 TIA/stroke patients with ipsilateral <70% carotid artery stenosis were randomly selected from a larger cohort. Five MR pulse sequences were acquired around the carotid bifurcation, each containing nine transverse slices: T1-weighted turbo field echo, time of flight, T2-weighted turbo spin-echo, and pre- and postcontrast T1-weighted turbo spin-echo images (T1W TSE). The images were manually segmented by delineating the lumen contour in each vessel wall sequence and were manually aligned by applying throughplane and inplane translations to the images. To find the optimal automatic image registration method, different masks, choice of the fixed image, different types of the mutual information image similarity metric, and transformation models including 3D deformable transformation models, were evaluated. Evaluation of the automatic registration results was performed by comparing the lumen segmentations of the fixed image and

  1. SEX DETERMINATION FROM FEMORAL HEAD DIAMETERS IN ...

    African Journals Online (AJOL)

    hi-tech

    2000-03-01

    Mar 1, 2000 ... Request for reprints to: Dr. P S Igbigbi, Department of Anatomy, College of Medicine, Private Bag 360 Chichiri, Blantyre 3 Malawi. SEX DETERMINATION .... Figure 2. Bar chart showing the ranges of head diameters of male and female femurs. (RVD-Right vertical diameter; LVD-Left vertical diameter; RTD -.

  2. 7 CFR 51.2850 - Diameter.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Diameter. 51.2850 Section 51.2850 Agriculture... Diameter. Diameter means the greatest dimension measured at right angles to a straight line running from the stem to the root. ...

  3. 7 CFR 51.3211 - Diameter.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Diameter. 51.3211 Section 51.3211 Agriculture... Standards for Grades of Bermuda-Granex-Grano Type Onions Definitions § 51.3211 Diameter. Diameter means the greatest dimension of the onion at right angles to a line running from the stem to the root. Metric...

  4. Impact of balloon inflation pressure on cell viability with single and multi lumen catheters.

    Science.gov (United States)

    Dib, N; Schwalbach, D B; Plourde, B D; Kohler, R E; Dana, D; Abraham, J P

    2014-12-01

    Infusion catheters, when used in combination with balloons, are subjected to pressure created by inflation of the balloon. The compression can reduce the catheter flow area and cause elevated shear stresses in the fluid. A model and experiments were developed with a range of applied balloon pressures to investigate whether such situations may cause cell lysis during stem-cell infusion through single-lumen catheters. It was found that for balloon inflation pressures in excess of ~7 atm, it is possible for cell injury to occur, although the critical pressure depends on the fluid viscosity. The study was then applied to a multi-lumen catheter which was designed to resist compression. That device was able to handle very elevated balloon pressures and flow rates before cell lysis became a concern.

  5. Regulating Ion Transport in Peptide Nanotubes by Tailoring the Nanotube Lumen Chemistry.

    Science.gov (United States)

    Ruiz, Luis; Benjamin, Ari; Sullivan, Matthew; Keten, Sinan

    2015-05-07

    We use atomistic nonequilibrium molecular dynamics simulations to demonstrate how specific ionic flux in peptide nanotubes can be regulated by tailoring the lumen chemistry through single amino acid substitutions. By varying the size and polarity of the functional group inserted into the nanotube interior, we are able to adjust the Na(+) flux by over an order of magnitude. Cl(-) is consistently denied passage. Bulky, nonpolar groups encourage interactions between the Na(+) and the peptide backbone carbonyl groups, disrupting the Na(+) solvation shell and slowing the transport of Na(+). Small groups have the opposite effect and accelerate flow. These results suggest that relative ion flux and selectivity can be precisely regulated in subnanometer pores by molecularly defining the lumen according to biological principles.

  6. Misoprostol in the intestinal lumen protects against radiation injury of the mucosa of the small bowel

    Energy Technology Data Exchange (ETDEWEB)

    Delaney, J.P.; Bonsack, M.E.; Felemovicius, I. (Univ. of Minnesota Medical School, Minneapolis, MN (United States))

    1994-03-01

    Systemically administered misoprostol, a PGE analog, has been shown to be an intestinal radioprotector. The purpose of this study was to determine if administration of misoprostol into the intestinal lumen can also reduce the severity of acute radiation enteritis. The rat small bowel was operatively exteriorized and segmented by means of suture ties. The remainder of the intestine and the rat were shielded in a lead box. Misoprostol was introduced into the lumen in various doses. After 30 min exposure to misoprostol, the isolated, exteriorized, segmented bowel was subjected to 11 Gy X irradiation. Five days later the animals were sacrificed and the intestines harvested for evaluation. Surviving crypt numbers per circumference and mucosal height were the criteria used for quantification of damage. Mucosa exposed to misoprostol at the time of radiation delivery showed significantly increased crypt numbers and mucosal height compared to adjacent saline-filled intestine. 24 refs., 2 figs., 2 tabs.

  7. Misoprostol in the intestinal lumen protects against radiation injury of the mucosa of the small bowel

    International Nuclear Information System (INIS)

    Delaney, J.P.; Bonsack, M.E.; Felemovicius, I.

    1994-01-01

    Systemically administered misoprostol, a PGE analog, has been shown to be an intestinal radioprotector. The purpose of this study was to determine if administration of misoprostol into the intestinal lumen can also reduce the severity of acute radiation enteritis. The rat small bowel was operatively exteriorized and segmented by means of suture ties. The remainder of the intestine and the rat were shielded in a lead box. Misoprostol was introduced into the lumen in various doses. After 30 min exposure to misoprostol, the isolated, exteriorized, segmented bowel was subjected to 11 Gy X irradiation. Five days later the animals were sacrificed and the intestines harvested for evaluation. Surviving crypt numbers per circumference and mucosal height were the criteria used for quantification of damage. Mucosa exposed to misoprostol at the time of radiation delivery showed significantly increased crypt numbers and mucosal height compared to adjacent saline-filled intestine. 24 refs., 2 figs., 2 tabs

  8. Difficulty in inserting left double-lumen endobronchial tubes at the cricoid level in small-statured women: A retrospective study

    Directory of Open Access Journals (Sweden)

    Mika Sato

    2017-01-01

    Full Text Available Background and Aims: Left double-lumen endobronchial tube (DLT sizes are selected using tracheal diameters and left mainstem bronchial diameters (LMBDs determined from chest radiographs or computed tomography (CT scans. In Western women, 35-Fr or 37-Fr DLTs are often selected. However, difficulties can be encountered when inserting 32-Fr or 35-Fr DLTs in Japanese women. We investigated success rates for 32-Fr or 35-Fr DLT insertion in Japanese women and determined the causes of unsuccessful DLT insertion. Methods: We searched anaesthesia records of Japanese women aged ≥20 years who underwent thoracic surgery with 32-Fr or 35-Fr DLTs between April 2010 and March 2015 in our hospital. In the successful group (SG, patients were intubated using the initially selected DLTs. By contrast, in the unsuccessful group (UG, the DLT size had to be changed. The Mann–Whitney U-test and Fisher's exact test were used to compare groups. Results: The SG included 149 (96.1% of 155 cases of 32-Fr DLT use and 119 (95.2% of 125 cases of 35-Fr DLT use. Patient height was significantly lower in the UG than in the SG for the 35-Fr DLT (P = 0.0036. In seven of 12 UG patients (three for 32-Fr and four for 35-Fr, the transverse diameters of cricoid cartilages were smaller than the DLTs' tracheal diameters, thereby preventing passage through the cricoid cartilages. Conclusion: Along with LMBDs, transverse diameters of cricoid cartilages based on CT scans or ultrasonogram findings may help in selecting the appropriate left DLT size.

  9. Two-year outcomes with a novel, double-lumen, saline-filled breast implant.

    Science.gov (United States)

    Nichter, Larry S; Hamas, Robert S

    2012-09-01

    A double-lumen, saline-filled breast implant with a baffle structure (IDEAL IMPLANT Saline-Filled Breast Implant; Ideal Implant Incorporated, Irving, Texas) was developed to overcome the limitations of single-lumen saline implants by controlling saline movement and providing internal support to the implant edge and upper pole. The authors report 2-year data from a 10-year US clinical trial evaluating the safety and effectiveness of this investigational implant. Women seeking primary breast augmentation or replacement of existing augmentation implants were enrolled between February 2009 and February 2010 at 35 private practice sites, where the women underwent surgery to receive the new technology implant. Data collection included incidence and grade of capsular contracture (CC) and wrinkling as well as patient- and surgeon-reported satisfaction measures. All clinical data were reported as Kaplan-Meier risk rates of first occurrence, per patient, in each cohort. Two-year follow-up visits were completed by 472 of 502 enrolled women (94.0%), 378 of whom had undergone primary breast augmentation and 94 of whom had received replacement augmentation. Patient-reported satisfaction with the outcome was 94.3% for primary augmentations and 92.3% for replacement augmentations; surgeon-reported satisfaction was also high (96.5% and 93.4%, respectively). Baker Grade III and IV CC rates were 3.8% (primary) and 8.2% (replacement), whereas moderate-to-severe wrinkling was 3.8% (primary) and 12.0% (replacement). Deflations occurred in 4.8% of primary augmentations and 3.3% of replacement augmentations. No deflations were caused by a shell fold flaw. Two-year data from 472 women indicate that this double-lumen saline implant containing a baffle structure has a low rate of wrinkling and a lower rate of CC at 2 years than was reported for current single-lumen saline implants at 1 year.

  10. Lumen and Chromaticity Maintenance of LED PAR38 Lamps Operated in Steady-State Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Royer, Michael P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-12-01

    The lumen depreciation and color shift of 38 different lamps (32 LED, 2 CFL, 1 ceramic metal halide [CMH], 3 halogen) were monitored in a specially developed automated long-term test apparatus (ALTA2) for nearly 14,000 hours. Five samples of each lamp model were tested, with measurements recorded on a weekly basis. The lamps were operated continuously at a target ambient temperature between 44°C and 45°C.

  11. Transport of UDP-galactose into the Golgi lumen regulates the biosynthesis of proteoglycans.

    Science.gov (United States)

    Toma, L; Pinhal, M A; Dietrich, C P; Nader, H B; Hirschberg, C B

    1996-02-16

    The lumen of the Golgi apparatus is the subcellular site where galactose is transferred, from UDP-galactose, to the oligosaccharide chains of glycoproteins, glycolipids, and proteoglycans. The nucleotide sugar, which is synthesized in the cytosol, must first be transported into the Golgi lumen by a specific UDP-galactose transporter. Previously, a mutant polarized epithelial cell (MDCKII-RCAr) with a 2% residual rate of transport of UDP-galactose into the lumen of Golgi vesicles was described (Brandli, A. W., Hansson, G. C., Rodriguez-Boulan, E., and Simons, K. (1988) J. Biol. Chem. 263, 16283-16290). The mutant has an enrichment in glucosyl ceramide and cell surface glycoconjugates bearing terminal N-acetylglucosamine, as well as a 75% reduction in sialylation of cell surface glycoproteins and glycosphingolipids. We have now studied the biosynthesis of galactose containing proteoglycans in this mutant and the corresponding parental cell line. Wild-type Madin-Darby canine kidney cells synthesize significant amounts of chondroitin sulfate, heparan sulfate, and keratan sulfate, while the above mutant synthesizes chondroitin sulfate and heparan sulfate but not keratan sulfate, the only proteoglycan containing galactose in its glycosaminoglycan polymer. The mutant also synthesizes chondroitin 6-sulfate rather than only chondroitin 4-sulfate as wild-type cells. Together, the above results demonstrate that the Golgi membrane UDP-galactose transporter is rate-limiting in the supply of UDP-galactose into the Golgi lumen; this in turn results in selective galactosylation of macromolecules. Apparently, the Km for galactosyltransferases involved in the synthesis of linkage regions of heparan sulfate and chondroitin sulfate are significantly lower than those participating in the synthesis of keratan sulfate polymer, glycoproteins, and glycolipids. The results also suggest that the 6-O-sulfotransferases, in the absence of their natural substrates (keratan sulfate) may catalyze

  12. Vertebral Artery Diameter and Flow: Nature or Nurture.

    Science.gov (United States)

    Tarnoki, Adam Domonkos; Fejer, Bence; Tarnoki, David Laszlo; Littvay, Levente; Lucatelli, Pierleone; Cirelli, Carlo; Fanelli, Fabrizio; Sacconi, Beatrice; Fagnani, Corrado; Medda, Emanuela; Farina, Filippo; Meneghetti, Giorgio; Horvath, Tamas; Pucci, Giacomo; Schillaci, Giuseppe; Stazi, Maria Antonietta; Baracchini, Claudio

    2017-09-01

    In contrast with the carotid arteries, the vertebral arteries (VAs) show considerable variation in length, caliber, and vessel course. This study investigated whether the variation in diameter and flow characteristics of the VAs might be inherited. A total of 172 Italian twins from Padua, Perugia, and Terni (54 monozygotic, 32 dizygotic) recruited from the Italian Twin Registry underwent B-mode and pulsed-wave Doppler ultrasound assessment of their VAs. VA diameters, peak systolic velocity (PSV) and end diastolic velocity (EDV) were assessed at the level of a horizontal V2 segment. Univariate quantitative genetic modeling was performed. Fourteen percent of the sample had VA hypoplasia. Within pair correlation in monozygotic twins was higher than in dizygotics (.552 vs. .229) for VA diameter. Age- and sex-adjusted genetic effect, under the most parsimonious model, accounted for 54.7% (95% CI: 42.2-69.1%) of the variance of VA diameter, and unshared environmental effect for 45.3% (95% CI: 30.9-57.8%). No heritability was found for the PSV of VA, but shared (34.1%; 95% CI: 16.7-53.7%) and unshared (65.9%; 95% CI: 45.9-83.1%) environmental factors determined the variance. EDV of VA is moderately genetically influenced (42.4%; 95% CI: 16.1-64.9%) and also determined by the unshared environment (57.6%; 95% CI: 34.7-83.7%). The diameter of the VAs is moderately genetically determined. Different factors influence the PSV and EDV of VAs, which may highlight the complex hemodynamic background of VA flow and help to understand the vertebral flow anomalies found by ultrasound. Copyright © 2017 by the American Society of Neuroimaging.

  13. Lumen Maintenance and Light Loss Factors: Consequences of Current Design Practices for LED's

    Energy Technology Data Exchange (ETDEWEB)

    Royer, Michael P.

    2013-09-17

    Synopsis: Light loss factors are used to help lighting systems meet quantitative design criteria throughout the life of the installation, but they also influence energy use. As the light sources currently being specified continue to evolve, it is necessary to reevaluate the methods used in calculating light loss factors, as well as carefully consider the consequences of different product performance attributes. Because of the unique operating characteristics of LEDs and lack of a comprehensive lifetime rating—as well as the problematic relationship between lifetime and lumen maintenance—determining an appropriate lamp lumen depreciation (LLD) factor for LED products is difficult. As a result, a unique solution has been advocated: when quantity of light is an important design consideration, the IES recommends using an LLD of not greater than 0.70. This method deviates from the typical practice for conventional sources of using the ratio of mean to initial lumen output, and can misrepresent actual performance, increase energy use, and inhibit comparisons between products. This paper discusses the complications related to LLD and LEDs, compares the performance of conventional and LED products, and examines alternatives to a maximum LLD of 0.70 for LEDs.

  14. Receptor-Type Guanylyl Cyclase at 76C (Gyc76C Regulates De Novo Lumen Formation during Drosophila Tracheal Development.

    Directory of Open Access Journals (Sweden)

    Monn Monn Myat

    Full Text Available Lumen formation and maintenance are important for the development and function of essential organs such as the lung, kidney and vasculature. In the Drosophila embryonic trachea, lumena form de novo to connect the different tracheal branches into an interconnected network of tubes. Here, we identify a novel role for the receptor type guanylyl cyclase at 76C (Gyc76C in de novo lumen formation in the Drosophila trachea. We show that in embryos mutant for gyc76C or its downsteam effector protein kinase G (PKG 1, tracheal lumena are disconnected. Dorsal trunk (DT cells of gyc76C mutant embryos migrate to contact each other and complete the initial steps of lumen formation, such as the accumulation of E-cadherin (E-cad and formation of an actin track at the site of lumen formation. However, the actin track and E-cad contact site of gyc76C mutant embryos did not mature to become a new lumen and DT lumena did not fuse. We also observed failure of the luminal protein Vermiform to be secreted into the site of new lumen formation in gyc76C mutant trachea. These DT lumen formation defects were accompanied by altered localization of the Arf-like 3 GTPase (Arl3, a known regulator of vesicle-vesicle and vesicle-membrane fusion. In addition to the DT lumen defect, lumena of gyc76C mutant terminal cells were shorter compared to wild-type cells. These studies show that Gyc76C and downstream PKG-dependent signaling regulate de novo lumen formation in the tracheal DT and terminal cells, most likely by affecting Arl3-mediated luminal secretion.

  15. Cheboygan Vessel Base

    Data.gov (United States)

    Federal Laboratory Consortium — Cheboygan Vessel Base (CVB), located in Cheboygan, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). CVB was established by congressional...

  16. Coastal Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch (landed catch) and effort for fishing trips made by vessels that have been issued a Federal permit for the Gulf of Mexico reef fish,...

  17. Vessel Sewage Discharges

    Science.gov (United States)

    Vessel sewage discharges are regulated under Section 312 of the Clean Water Act, which is jointly implemented by the EPA and Coast Guard. This homepage links to information on marine sanitation devices and no discharge zones.

  18. High Performance Marine Vessels

    CERN Document Server

    Yun, Liang

    2012-01-01

    High Performance Marine Vessels (HPMVs) range from the Fast Ferries to the latest high speed Navy Craft, including competition power boats and hydroplanes, hydrofoils, hovercraft, catamarans and other multi-hull craft. High Performance Marine Vessels covers the main concepts of HPMVs and discusses historical background, design features, services that have been successful and not so successful, and some sample data of the range of HPMVs to date. Included is a comparison of all HPMVs craft and the differences between them and descriptions of performance (hydrodynamics and aerodynamics). Readers will find a comprehensive overview of the design, development and building of HPMVs. In summary, this book: Focuses on technology at the aero-marine interface Covers the full range of high performance marine vessel concepts Explains the historical development of various HPMVs Discusses ferries, racing and pleasure craft, as well as utility and military missions High Performance Marine Vessels is an ideal book for student...

  19. 2013 Fishing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  20. Reactor pressure vessel support

    International Nuclear Information System (INIS)

    Butti, J.P.

    1978-01-01

    A link and pin support system provides the primary vertical and lateral support for a nuclear reactor pressure vessel without restricting thermally induced radial and vertical expansion and contraction

  1. 2013 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  2. Maury Journals - US Vessels

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. vessels observations, after the 1853 Brussels Conference that set International Maritime Standards, modeled after Maury Marine Standard Observations.

  3. 2013 Tanker Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  4. 2013 Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  5. Ocean Station Vessel

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ocean Station Vessels (OSV) or Weather Ships captured atmospheric conditions while being stationed continuously in a single location. While While most of the...

  6. 2011 Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  7. 2011 Fishing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  8. 2011 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  9. Pressurized Vessel Slurry Pumping

    International Nuclear Information System (INIS)

    Pound, C.R.

    2001-01-01

    This report summarizes testing of an alternate ''pressurized vessel slurry pumping'' apparatus. The principle is similar to rural domestic water systems and ''acid eggs'' used in chemical laboratories in that material is extruded by displacement with compressed air

  10. 2013 Passenger Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  11. Diffusion MRI for rectal cancer staging: ADC measurements before and after ultrasonographic gel lumen distension

    Energy Technology Data Exchange (ETDEWEB)

    Palmucci, S., E-mail: spalmucci@sirm.org; Piccoli, M.; Piana, S.; Foti, P.V.; Siverino, R.O.A.; Mauro, L.A.; Milone, P.; Ettorre, G.C.

    2017-01-15

    Objectives: To compare Apparent Diffusion Coefficient (ADC) measurements in rectal neoplastic lesions before and after lumen distension obtained with sonography transmission gel. Methods: From January 2014 to July 2016, 25 patients (average age 63.7, range 41–85, 18 males) were studied for pre-treatment rectal cancer staging using a 1.5 T MRI. Diffusion MRI was obtained using echo-planar imaging with b = 800 value; all patients were studied acquiring diffusion sequences with and without rectal lumen distension obtained using sonography transmission gel. In both diffusion sequences, two blinded readers calculated border ADC values and small ADC values, drawing regions of interest respectively along tumour borders and far from tumour borders. Mean ADC values among readers − for each type of ADC measurement − were compared using Wilcoxon matched pairs signed rank test. Correlation was assessed using Pearson analysis. Results: Border ADC mean value for diffusion MR sequences without endorectal contrast was 1.122 mm{sup 2}/sec, with 95% Confidence Interval (CI) = 1.02–1.22; using gel lumen distension, higher border ADC mean value of 1.269 mm{sup 2}/s (95% CI = 1.16–1.38) was obtained. Wilcoxon matched pairs signed rank test revealed statistical difference (p < 0.01); a strong Pearson correlation was reported, with r value of 0.69. Small-ADC mean value was 1.038 mm{sup 2}/s (95% CI = 0.91–1.16) for diffusion sequences acquired without endorectal distension and 1.127 mm{sup 2}/s (95% CI = 0.98–1.27) for diffusion sequences obtained after endorectal gel lumen distension. Wilcoxon analysis did not show statistical difference (p = 0.13). A very strong positive correlation was observed, with r value of 0.81. Conclusions: ADC measurements are slightly higher using endorectal sonographic transmission gel; ROI should be traced far from tumour borders, to minimize gel filled-pixel along the interface between lumen and lesion. Further studies are needed to

  12. Oesophageal lumen pH in yearling horses and effects of management and administration of omeprazole.

    Science.gov (United States)

    Wilson, C S; Brookes, V J; Hughes, K J; Trope, G D; Ip, H; Gunn, A J

    2017-05-01

    In human subjects, arytenoid chondritis can be caused by chemical trauma of mucosa attributable to gastro-oesophageal reflux. Although a similar process may be involved in the aetiopathogenesis of arytenoid chondritis in horses, the oesophageal lumen pH in this species is poorly understood. To determine if gastro-oesophageal reflux occurs in horses by characterising oesophageal lumen pH. Blinded, randomised, placebo-controlled, crossover, experimental study. Luminal oesophageal pH in six yearling horses was recorded over four 24 h periods using an ambulatory pH recorder attached to a catheter with two electrodes (proximal and distal) inserted into the oesophagus. Recordings of pH were made during three management protocols. Initially, horses grazed in a paddock (Protocol A). Horses were then moved to stables to simulate sale preparation of Thoroughbred yearlings, and were given either omeprazole (Protocol B) or placebo paste (Protocol C) orally once per day. Protocol A was repeated for each horse (after a 13 day washout period) between Protocols B and C. Summary statistics described pH range and frequency of pH changes. Associations with predictor variables were investigated using linear mixed-effects models. Data are presented as the mean ± s.d. Oesophageal lumen pH ranged from 4.90 to 9.70 (7.36 ± 0.27 and 7.18 ± 0.24 for the proximal and distal electrodes, respectively) and varied frequently (1.2 ± 0.9 changes/min and 0.8 ± 0.8 changes/min for the proximal and distal electrodes, respectively). Oesophageal lumen pH was associated with time since concentrate feeding, activity and time of day, but not with treatment of omeprazole. A small number of horses were used and measurement periods were limited. Gastro-oesophageal reflux occurs in clinically normal yearling horses. Although omeprazole had no detectable effect, oesophageal lumen pH recorded during this study did not fall within the therapeutic range of omeprazole. © 2016 EVJ Ltd.

  13. LANL Robotic Vessel Scanning

    Energy Technology Data Exchange (ETDEWEB)

    Webber, Nels W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-25

    Los Alamos National Laboratory in J-1 DARHT Operations Group uses 6ft spherical vessels to contain hazardous materials produced in a hydrodynamic experiment. These contaminated vessels must be analyzed by means of a worker entering the vessel to locate, measure, and document every penetration mark on the vessel. If the worker can be replaced by a highly automated robotic system with a high precision scanner, it will eliminate the risks to the worker and provide management with an accurate 3D model of the vessel presenting the existing damage with the flexibility to manipulate the model for better and more in-depth assessment.The project was successful in meeting the primary goal of installing an automated system which scanned a 6ft vessel with an elapsed time of 45 minutes. This robotic system reduces the total time for the original scope of work by 75 minutes and results in excellent data accumulation and transmission to the 3D model imaging program.

  14. Pressure vessel, in particular reactor pressure vessel

    International Nuclear Information System (INIS)

    1976-01-01

    The task to design the pre-stressing facility for a pressure vessel, especially for nuclear reactors, wiht pre-stressed jacket and pre-stressing facility, the latter one showing circumferential steel tendons supported polygonally on the outer side of the jacket by means of supporting shoes, in such a way that simply defined tensions can be generated and re-tensioning of the tendons can be carried out easily is solved according to the invention by keeping the circumference of the steel tendons fixed and by designing the supporting shoes as stressing shoes. The defined tensions are applied through the stressing shoes. (ORU) [de

  15. Summary of Activities for Health Monitoring of Composite Overwrapped Pressure Vessels Updated January 2014

    Science.gov (United States)

    Skow, Miles G.

    2014-01-01

    This three year project (FY12-14) will design and demonstrate the ability of new Magnetic Stress Gages for the measurement of stresses on the inner diameter of a Composite Overwrapped Pressure Vessel overwrap.

  16. Characterization of swallow modulation in response to bolus volume in healthy subjects accounting for catheter diameter.

    Science.gov (United States)

    Ferris, Lara; Schar, Mistyka; McCall, Lisa; Doeltgen, Sebastian; Scholten, Ingrid; Rommel, Nathalie; Cock, Charles; Omari, Taher

    2017-08-31

    Characterization of the pharyngeal swallow response to volume challenges is important for swallowing function assessment. The diameter of the pressure-impedance recording catheter may influence these results. In this study, we captured key physiological swallow measures in response to bolus volume utilizing recordings acquired by two catheters of different diameter. Ten healthy adults underwent repeat investigations with 8- and 10-Fr catheters. Liquid bolus swallows of volumes 2.5, 5, 10, 20, and 30 mL were recorded. Measures indicative of distension, contractility, and flow timing were assessed. Pressure-impedance recordings with pressure-flow analysis were used to capture key distension, contractility, and pressure-flow timing parameters. Larger bolus volumes increased upper esophageal sphincter distension diameter (P < .001) and distension pressures within the hypopharynx and upper esophageal sphincter (P < .05). Bolus flow timing measures were longer, particularly latency of bolus propulsion ahead of the pharyngeal stripping wave (P < .001). Use of a larger-diameter catheter produced higher occlusive pressures, namely upper esophageal sphincter basal pressure (P < .005) and upper esophageal sphincter postdeglutitive pressure peak (P < .001). The bolus volume swallowed changed measurements indicative of distension pressure, luminal diameter, and pressure-flow timing; this is physiologically consistent with swallow modulation to accommodate larger, faster-flowing boluses. Additionally, catheter diameter predominantly affects lumen occlusive pressures. Appropriate physiological interpretation of the pressure-impedance recordings of pharyngeal swallowing requires consideration of the effects of volume and catheter diameter. NA Laryngoscope, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  17. Mast cells present protrusions into blood vessels upon tracheal allergen challenge in mice.

    Directory of Open Access Journals (Sweden)

    Oishee Bose

    Full Text Available Mast cells (MC and myeloid dendritic cells (DC act proximally in detecting and processing antigens and immune insults. We sought to understand their comparative dynamic behavior with respect to the airway epithelium in the steady state and in response to an allergic stimulus in mouse trachea. We devised methods to label MC in living trachea and to demonstrate that MC and DC occupy distinct layers of the tracheal mucosa, with DC being closer to the lumen. DC numbers doubled after allergen challenge, but MC numbers remained stable. MC and DC migrated minimally in either steady state or allergen-challenge conditions, and their interactions with one another appeared to be stochastic and relatively infrequent. While DC, unlike MC, exhibited probing behaviors involving dendrites, these projections did not cross the epithelium into the airway lumen. MC typically were located too far from the epithelial surface to contact the tracheal lumen. However, MC had protrusions toward and into blood vessels, likely to load with IgE. Thus, DC and MC occupy distinct niches and engage in sessile surveillance in the mouse trachea. Little or no access of these cell types to the airway lumen suggests that trans-epithelial transport of proteins in the steady state would be required for them to access luminal antigens.

  18. Modular Small Diameter Vascular Grafts with Bioactive Functionalities

    Science.gov (United States)

    Neufurth, Meik; Wang, Xiaohong; Tolba, Emad; Dorweiler, Bernhard; Schröder, Heinz C.; Link, Thorben; Diehl-Seifert, Bärbel; Müller, Werner E. G.

    2015-01-01

    We report the fabrication of a novel type of artificial small diameter blood vessels, termed biomimetic tissue-engineered blood vessels (bTEBV), with a modular composition. They are composed of a hydrogel scaffold consisting of two negatively charged natural polymers, alginate and a modified chitosan, N,O-carboxymethyl chitosan (N,O-CMC). Into this biologically inert scaffold two biofunctionally active biopolymers are embedded, inorganic polyphosphate (polyP) and silica, as well as gelatin which exposes the cell recognition signal, Arg-Gly-Asp (RGD). These materials can be hardened by exposure to Ca2+ through formation of Ca2+ bridges between the polyanions, alginate, N,O-CMC, and polyP (alginate-Ca2+-N,O-CMC-polyP). The bTEBV are formed by pressing the hydrogel through an extruder into a hardening solution, containing Ca2+. In this universal scaffold of the bTEBV biomaterial, polycations such as poly(l-Lys), poly(d-Lys) or a His/Gly-tagged RGD peptide (three RGD units) were incorporated, which promote the adhesion of endothelial cells to the vessel surface. The mechanical properties of the biopolymer material (alginate-Ca2+-N,O-CMC-polyP-silica) revealed a hardness (elastic modulus) of 475 kPa even after a short incubation period in CaCl2 solution. The material of the artificial vascular grafts (bTEBVs with an outer size 6 mm and 1.8 mm, and an inner diameter 4 mm and 0.8 mm, respectively) turned out to be durable in 4-week pulsatile flow experiments at an alternating pressure between 25 and 100 mbar (18.7 and 75.0 mm Hg). The burst pressure of the larger (smaller) vessels was 850 mbar (145 mbar). Incorporation of polycationic poly(l-Lys), poly(d-Lys), and especially the His/Gly-tagged RGD peptide, markedly increased the adhesion of human, umbilical vein/vascular endothelial cells, EA.HY926 cells, to the surface of the hydrogel. No significant effect of the polyP samples on the clotting of human plasma is measured. We propose that the metabolically degradable

  19. Defective pericyte recruitment of villous stromal vessels as the possible etiologic cause of hydropic change in complete hydatidiform mole.

    Directory of Open Access Journals (Sweden)

    Kyu Rae Kim

    Full Text Available The pathogenetic mechanism underlying the hydropic change in complete hydatidiform moles (CHMs is poorly understood. A growing body of data suggests that pericytes play a role in vascular maturation. Since maturation of villous stromal vessels in CHMs is markedly impaired at early stages, we postulated that a defect in pericytes around stromal vessels in chorionic villi might cause vascular immaturity and subsequent hydropic change. To investigate this, we examined several markers of pericytes, namely, α-smooth muscle actin (α-SMA, platelet-derived growth factor receptor-β (PDGFR-β, and desmin, in 61 normally developing placentas and 41 CHMs with gestational ages of 4-12 weeks. The ultrastructure of villous stromal vessels was also examined. Mature blood vessels from normal placentas show patent vascular lumens and formed hematopoietic components in the villous stroma. α-SMA and PDGFR-β expression in the villous stroma gradually increased and extended from the chorionic plate to peripheral villous branches. The labeled cells formed a reticular network in the villous stroma and, after week 7, encircled villous stromal vessels. In comparison, α-SMA and PDGFR-β expression in the villous stroma and stromal vessels of CHMs was significantly lower (p<0.05. Ultrastructurally, endothelial cells in villous stromal vessels in normal placentas were consistently attached by pericytes after week 7 when the vessels formed distinct lumen, whereas the villous stromal vessels in CHMs consisted of linear chains of endothelial cells, often disclosing primitive clefts without hematopoietic cells inside, and neither pericytes nor basal lamina surrounded the endothelial cells at any gestational age studied. This suggests that pericytes recruitment around villous stromal vessels is defective in CHMs and links to the persistent vascular immaturity of the villous stroma in CHMs, which in turns leads to hydropic villi.

  20. Construction of tissue-engineered small-diameter vascular grafts in fibrin scaffolds in 30 days.

    Science.gov (United States)

    Gui, Liqiong; Boyle, Michael J; Kamin, Yishai M; Huang, Angela H; Starcher, Barry C; Miller, Cheryl A; Vishnevetsky, Michael J; Niklason, Laura E

    2014-05-01

    Tissue-engineered small-diameter vascular grafts have been developed as a promising alternative to native veins or arteries for replacement therapy. However, there is still a crucial need to improve the current approaches to render the tissue-engineered blood vessels more favorable for clinical applications. A completely biological blood vessel (3-mm inner diameter) was constructed by culturing a 50:50 mixture of bovine smooth muscle cells (SMCs) with neonatal human dermal fibroblasts in fibrin gels. After 30 days of culture under pulsatile stretching, the engineered blood vessels demonstrated an average burst pressure of 913.3±150.1 mmHg (n=6), a suture retention (53.3±15.4 g) that is suitable for implantation, and a compliance (3.1%±2.5% per 100 mmHg) that is comparable to native vessels. These engineered grafts contained circumferentially aligned collagen fibers, microfibrils and elastic fibers, and differentiated SMCs, mimicking a native artery. These promising mechanical and biochemical properties were achieved in a very short culture time of 30 days, suggesting the potential of co-culturing SMCs with fibroblasts in fibrin gels to generate functional small-diameter vascular grafts for vascular reconstruction surgery.

  1. Assessment of lumen degradation and remaining useful life of LEDs using particle filter

    Energy Technology Data Exchange (ETDEWEB)

    Lall, Pradeep [Auburn Univ., AL (United States); Zhang, Hao [Auburn Univ., AL (United States); Davis, Lynn [Auburn Univ., AL (United States)

    2013-07-16

    With the development of light-emitting diode (LED) technology, light emitting diodes system is becoming a popular light source in daily life and industry area. It has shown that Led from same factory and work under same working condition, may have significantly different behavior. Therefore, it is very important to learn the fail mechanisms, especially in the case of safety critical and harsh environment application. This paper focus on a prognostic health management (PHM) method based on the measurement of forward voltage and forward current of bare LED under harsh environment. In this paper, experiment has been done with ten samples. Ten pristine bare LEDs have been tested at 85°C while simultaneously being subjected to 85% humid environment. Pulse width modulation (PWM) control method has been employed to drive the bare LED in order to reduce the heat effect caused by forward current and high frequency (300HZ) data acquisition has been used to measure the peak forward voltage and forward current. Test to failure (lumen drops to 70 percent) data has been measured to study the effects of high temperature and humid environment loadings on the bare LED. Also, solid state cooling method with peltier cooler has been used to control the temperature of LED in the integrating sphere when take the measurement of lumen flux. The shift of forward voltage forward current curve and lumen degradation has been recorded to help build the fail model and predicted the remaining useful life. In this method, particle filter has been employed to predict the remaining useful life (RUL) of the bare LED and give us a whole picture how Led system fails. Result shows that predication of remaining useful life of Led, made by the particle filter model works under reasonable limit, and hence this method can be employed to predict the failure of Led caused by thermal and humid stress under harsh environment.

  2. Select nutrients in the uterine lumen of sheep and pigs affect conceptus development.

    Science.gov (United States)

    Bazer, Fuller W; Kim, Jinyoung; Ka, Hakhyun; Johnson, Gregory A; Wu, Guoyao; Song, Gwonhwa

    2012-01-01

    Interferon tau (IFNT) is the pregnancy recognition signal from ruminant conceptuses. IFNT also acts with P4 to induce expression of genes for transport of nutrients, such as glucose (Gluc) and arginine (Arg) into the uterine lumen to activate mechanistic mammalian target of rapamycin (MTOR) cell signaling that stimulates proliferation, migration, gene transcription and mRNA translation by conceptus trophectoderm (Tr). In ewes, Arg and Gluc increase significantly in the uterine lumen between Days 10 and 15 of pregnancy due to increased expression of transporters for Gluc (SLC2A1 and SLC5A1) and Arg (SLC7A2B) by uterine epithelia. Arg and Gluc stimulate proliferation, migration and mRNA translation by Tr. Arg increases expression of GTP cyclohydrolase 1 (GCH1) and IFNT mRNAs while Arg and Gluc increase ornithine decarboxylase, nitric oxide synthase 2, and GCH1 mRNAs and proteins by Tr cells. GCH1 is required for synthesis of tetrahydrobiopterin, an essential cofactor for all NOS isoforms. Arg is metabolized to nitric oxide and polyamines that increase proliferation and migration of Tr cells. In pigs, Gluc, Arg, leucine (Leu) and glutamine (Gln) increase in the uterine lumen between Days 12 and 15 of pregnancy due to enhanced expression of transporters for Gluc and amino acids. Transporters for Gluc in porcine uterine LE (SLC2A1) and conceptus trophectoderm (SLC2A2) are abundant. Transporters for glutamate and neutral (SLC1A1, SLC1A4) and cationic (SLC7A1, SLC7A2, SLC7A7, SLC7A9) amino acids are expressed in uterine LE and SLC7A3 mRNA is expressed in conceptus Tr. Arg and Leu increase MTOR cell signaling and proliferation of pig Tr, as do Gluc and fructose. Azaserine, an inhibitor of hexosamine biosynthesis, inhibits effects of Gluc and fructose. Thus, select nutrients in the uterine lumen affect gene transcription and mRNA translation to affect conceptus development.

  3. Migration of ingested sewing needle from within sigmoid colon to outside of the lumen.

    Science.gov (United States)

    Cevizci, Mehmet Nuri; Demir, Muhammet; Demir, Berrin; Demir, Ilknur; Kilic, Omer

    2014-01-01

    Foreign body ingestion is a frequently observed condition in children. However, migration of an ingested foreign body from the gastrointestinal tract toward any abdominal organ is extremely rare. We report herein a case of a 2-year-old female patient in whom an ingested sewing needle was palpable by rectal examination and was determined to have migrated from within the sigmoid colon to outside of the lumen. The needle was surgically removed. In cases of foreign body ingestion, both physical examination and radiological follow-up should be performed.

  4. Prediction of L70 lumen maintenance and chromaticity for LEDs using extended Kalman filter models

    Energy Technology Data Exchange (ETDEWEB)

    Lall, Pradeep; Wei, Junchao; Davis, Lynn

    2013-09-30

    Solid-state lighting (SSL) luminaires containing light emitting diodes (LEDs) have the potential of seeing excessive temperatures when being transported across country or being stored in non-climate controlled warehouses. They are also being used in outdoor applications in desert environments that see little or no humidity but will experience extremely high temperatures during the day. This makes it important to increase our understanding of what effects high temperature exposure for a prolonged period of time will have on the usability and survivability of these devices. Traditional light sources “burn out” at end-of-life. For an incandescent bulb, the lamp life is defined by B50 life. However, the LEDs have no filament to “burn”. The LEDs continually degrade and the light output decreases eventually below useful levels causing failure. Presently, the TM-21 test standard is used to predict the L70 life of LEDs from LM-80 test data. Several failure mechanisms may be active in a LED at a single time causing lumen depreciation. The underlying TM-21 Model may not capture the failure physics in presence of multiple failure mechanisms. Correlation of lumen maintenance with underlying physics of degradation at system-level is needed. In this paper, Kalman Filter (KF) and Extended Kalman Filters (EKF) have been used to develop a 70-percent Lumen Maintenance Life Prediction Model for LEDs used in SSL luminaires. Ten-thousand hour LM-80 test data for various LEDs have been used for model development. System state at each future time has been computed based on the state space at preceding time step, system dynamics matrix, control vector, control matrix, measurement matrix, measured vector, process noise and measurement noise. The future state of the lumen depreciation has been estimated based on a second order Kalman Filter model and a Bayesian Framework. The measured state variable has been related to the underlying damage using physics-based models. Life

  5. The microbiota mediates pathogen clearance from the gut lumen after non-typhoidal Salmonella diarrhea.

    Directory of Open Access Journals (Sweden)

    Kathrin Endt

    Full Text Available Many enteropathogenic bacteria target the mammalian gut. The mechanisms protecting the host from infection are poorly understood. We have studied the protective functions of secretory antibodies (sIgA and the microbiota, using a mouse model for S. typhimurium diarrhea. This pathogen is a common cause of diarrhea in humans world-wide. S. typhimurium (S. tm(att, sseD causes a self-limiting gut infection in streptomycin-treated mice. After 40 days, all animals had overcome the disease, developed a sIgA response, and most had cleared the pathogen from the gut lumen. sIgA limited pathogen access to the mucosal surface and protected from gut inflammation in challenge infections. This protection was O-antigen specific, as demonstrated with pathogens lacking the S. typhimurium O-antigen (wbaP, S. enteritidis and sIgA-deficient mice (TCRβ(-/-δ(-/-, J(H (-/-, IgA(-/-, pIgR(-/-. Surprisingly, sIgA-deficiency did not affect the kinetics of pathogen clearance from the gut lumen. Instead, this was mediated by the microbiota. This was confirmed using 'L-mice' which harbor a low complexity gut flora, lack colonization resistance and develop a normal sIgA response, but fail to clear S. tm(att from the gut lumen. In these mice, pathogen clearance was achieved by transferring a normal complex microbiota. Thus, besides colonization resistance ( = pathogen blockage by an intact microbiota, the microbiota mediates a second, novel protective function, i.e. pathogen clearance. Here, the normal microbiota re-grows from a state of depletion and disturbed composition and gradually clears even very high pathogen loads from the gut lumen, a site inaccessible to most "classical" immune effector mechanisms. In conclusion, sIgA and microbiota serve complementary protective functions. The microbiota confers colonization resistance and mediates pathogen clearance in primary infections, while sIgA protects from disease if the host re-encounters the same pathogen. This has

  6. Reactor pressure vessel materials

    International Nuclear Information System (INIS)

    Suzuki, K.

    1998-01-01

    As a result of the popularity of the Agencies report 'Neutron Irradiation Embrittlement of Reactor Pressure Vessel Steels' of 1975, it was decided that another report on this broad subject would be of use. In this report, background and contemporary views on specially identified areas of the subject are considered as self-contained chapters, written by experts. Chapter 3 offers a detailed treatment of the selection criteria and properties of reactor pressure vessel materials. The main attention is directed towards steel and ingot making and the subsequent material processing

  7. Sapphire tube pressure vessel

    Science.gov (United States)

    Outwater, John O.

    2000-01-01

    A pressure vessel is provided for observing corrosive fluids at high temperatures and pressures. A transparent Teflon bag contains the corrosive fluid and provides an inert barrier. The Teflon bag is placed within a sapphire tube, which forms a pressure boundary. The tube is received within a pipe including a viewing window. The combination of the Teflon bag, sapphire tube and pipe provides a strong and inert pressure vessel. In an alternative embodiment, tie rods connect together compression fittings at opposite ends of the sapphire tube.

  8. Vasodilator effect of nicorandil on retinal blood vessels in rats.

    Science.gov (United States)

    Ogawa, Naoto; Saito, Maki; Mori, Asami; Sakamoto, Kenji; Kametaka, Sokichi; Nakahara, Tsutomu; Ishii, Kunio

    2007-07-01

    We examined the effect of nicorandil on retinal blood vessels in rats in vivo. Male Wistar rats (8 to 10 weeks old) were anaesthetised with thiobutabarbital (120 mg/kg, intraperitoneal). Fundus images were captured with a digital camera that was equipped with a special objective lens. Diameters of retinal blood vessels were measured with a personal computer. Nicorandil (1-300 microg kg(-1) min(-1), intravenous [i.v.]) increased diameters of retinal blood vessels and decreased systemic blood pressure in a dose-dependent manner. Both responses to nicorandil were attenuated by glibenclamide (20 mg/kg, i.v.), an adenosine triphosphate (ATP)-dependent K(+) (K(ATP)) channel blocker. On the other hand, indomethacin (5 mg/kg, i.v.), a cyclooxygenase inhibitor, attenuated the vasodilation of retinal blood vessels, but not depressor response, to nicorandil and sodium nitroprusside. Pinacidil (1-300 microg kg(-1) min(-1), i.v.), a K(ATP) channel opener, also dilated retinal blood vessels and decreased systemic blood pressure. The responses to pinacidil were prevented by glibenclamide, but not by indomethacin. The vasodilation of retinal arteriole, but not depressor response, to sodium nitroprusside (1-30 microg kg(-1) min(-1), i.v.), a nitric oxide donor, was attenuated by indomethacin. These results suggest that nicorandil dilates retinal blood vessels through opening of K(ATP) channels and production of prostaglandins that are probably generated by nitric oxide.

  9. The use of a Colapinto TIPS Needle under cone-beam computed tomography guidance for true lumen re-entry in subintimal recanalization of chronic iliac artery occlusion.

    Science.gov (United States)

    Liang, Huei-Lung; Li, Ming-Feng; Chiang, Chia-Ling; Chen, Matt Chiung-Yu; Wu, Chieh-Jen; Pan, Huay-Ben

    2017-06-01

    To report the technique and clinical outcome of subintimal re-entry in chronic iliac artery occlusion by using a Colapinto transjugular intrahepatic portosystemic shunt (TIPS) needle under rotational angiography (cone-beam computed tomography; CT) imaging guidance. Patients with chronic iliac artery occlusion with earlier failed attempts at conventional percutaneous recanalization during the past 5 years were enrolled in our study. In these patients, an ipsilateral femoral access route was routinely utilized in a retrograde fashion. A Colapinto TIPS Needle was used to aid the true lumen re-entry after failed conventional intraluminal or subintimal guidewire and catheter-based techniques. The puncture was directed under rotational angiography cone-beam CT guidance to re-enter the abdominal aorta. Bare metallic stents 8-10 mm in diameter were deployed in the common iliac artery, and followed by balloon dilation. Ten patients (9 male; median age, 75 years) were included in our investigation. The average occlusion length was 10.2 cm (range, 4-15 cm). According to the Trans-Atlantic Inter-Society Consensus (TASC) II classification, there were five patients each with Class B and D lesions. Successful re-entry was achieved in all patients without procedure-related complications. The ankle-brachial index (ABI) values increased from 0.38-0.79 to 0.75-1.28 after the procedure. Imaging follow-up (> 6 months) was available in six patients with patency of all stented iliac artery. Thereafter, no complaints of recurrent clinical symptoms occurred during the follow-up period. The use of Colapinto TIPS needle, especially under cone-beam CT image guidance, appears to be safe and effective to re-enter the true lumen in a subintimal angioplasty for a difficult chronic total iliac occlusion. Copyright © 2017. Published by Elsevier Taiwan LLC.

  10. Demystifying the use of internal mammary vessels as recipient vessels in free flap breast reconstruction.

    Science.gov (United States)

    Chang, Eric I; Chang, Edward I; Soto-Miranda, Miguel A; Nosrati, Naveed; Robb, Geoffrey L; Chang, David W

    2013-10-01

    The internal mammary vessels are commonly used as primary recipient vessels for free flap breast reconstruction. However, there is debate about the reliability of the left internal mammary vein. The authors explored the anatomy of the internal mammary vessels as revealed during free flap breast reconstruction to determine whether microvascular complications differed between the left and right sides. All free flap breast reconstructions performed using internal mammary recipient vessels at the authors' institution between January of 2000 and December of 2010 were reviewed. The authors compared left and right breast reconstructions for internal mammary vessel diameters and microvascular complications, pedicle thrombosis, and total flap losses. Overall, 1773 free flap breast reconstructions were performed in 1336 patients using the internal mammary vessels: 899 unilateral and 437 bilateral. The left side was used in 904 cases and the right side in 869 cases. Although the mean sizes of the left and right internal mammary arteries (2.44 and 2.47 mm, respectively) did not differ significantly, the left vein was significantly smaller than the right vein (2.47 mm versus 2.93 mm; p = 0.038). The overall rate of venous thrombosis was significantly higher on the left than on the right (3.0 percent versus 2.3 percent; p = 0.028). The rates of flap loss in left and right breast reconstructions did not differ significantly (1.9 percent versus 2.2 percent). Although the left internal mammary vein is smaller than the right and is at higher risk for venous complications, it remains an acceptable recipient vessel for free flap breast reconstruction. Therapeutic, III.

  11. The reactor vessel steels

    International Nuclear Information System (INIS)

    Bilous, W.; Hajewska, E.; Szteke, W.; Przyborska, M.; Wasiak, J.; Wieczorkowski, M.

    2005-01-01

    In the paper the fundamental steels using in the construction of pressure vessel water reactor are discussed. The properties of these steels as well as the influence of neutron irradiation on its degradation in the time of exploitation are also done. (authors)

  12. GOLD PRESSURE VESSEL SEAL

    Science.gov (United States)

    Smith, A.E.

    1963-11-26

    An improved seal between the piston and die member of a piston-cylinder type pressure vessel is presented. A layer of gold, of sufficient thickness to provide an interference fit between the piston and die member, is plated on the contacting surface of at least one of the members. (AEC)

  13. Reactor vessel stud tensioner

    International Nuclear Information System (INIS)

    Malandra, L.J.; Beer, R.W.; Salton, R.B.; Spiegelman, S.R.; Cognevich, M.L.

    1982-01-01

    A quick-acting stud tensioner, for facilitating the loosening or tightening of a stud nut on a reactor vessel stud, has gripper jaws which when the tensioner is lowered into engagement with the upper end of the stud are moved inwards to grip the upper end and which when the tensioner is lifted move outward to release the upper end. (author)

  14. Nuclear reactor vessels

    International Nuclear Information System (INIS)

    Sato, Yoshimi; Fukuda, Yoshio.

    1987-01-01

    Purpose: To improve the strength and reliability by moderating thermal stresses produced to the furnace walls of a reactor vessel by the thermal shocks upon reactor shutdown and tripping and reducing the generation of developing thermal ratchet strains produced upon repeating thermal shocks. Constitution: Upon occurrence of reactor shutdown or tripping, the temperature is detected and the pressure of the cover gas is controlled such that the axial temperature slope is decreased to displace the liquid surface in an annular vessel. Then, for attaining the stress reducing temperature, control is so conducted that the temperature of the lower portion is not higher than the upper portion in the axial temperature distribution of the reactor vessel. By controlling the pressure of the cover gas in the annular vessel in this way, the liquid level can be raised to a cover gas portion remaining at a high temperature state. Further, the temperature of the furnace wall can always be decreased to a temperature of the high temperature plenum thereby enabling to moderate the thermal stresses. (Yoshihara, H.)

  15. Pressure vessel integrity 1991

    International Nuclear Information System (INIS)

    Bhandari, S.; Doney, R.O.; McDonald, M.S.; Jones, D.P.; Wilson, W.K.; Pennell, W.E.

    1991-01-01

    This volume contains papers relating to the structural integrity assessment of pressure vessels and piping, with special emphasis on nuclear industry applications. The papers were prepared for technical sessions developed under the sponsorship of the ASME Pressure Vessels and Piping Division Committees for Codes and Standards, Computer Technology, Design and Analysis, and Materials Fabrication. They were presented at the 1991 Pressure Vessels and Piping Division Conference in San Diego, California, June 23-27. The primary objective of the sponsoring organization is to provide a forum for the dissemination and discussion of information on development and application of technology for the structural integrity assessment of pressure vessels and piping. This publication includes contributions from authors from Australia, France, Japan, Sweden, Switzerland, the United Kingdom, and the United States. The papers here are organized in six sections, each with a particular emphasis as indicated in the following section titles: Fracture Technology Status and Application Experience; Crack Initiation, Propagation and Arrest; Ductile Tearing; Constraint, Stress State, and Local-Brittle-Zones Effects; Computational Techniques for Fracture and Corrosion Fatigue; and Codes and Standards for Fatigue, Fracture and Erosion/Corrosion

  16. Intestinal fructose malabsorption is associated with increased lactulose fermentation in the intestinal lumen.

    Science.gov (United States)

    Ozaki, Roberto Koity Fujihara; Speridião, Patrícia da Graça Leite; Soares, Ana Cristina Fontenele; Morais, Mauro Batista de

    2017-10-28

    To study fructose malabsorption in children and adolescents with abdominal pain associated with functional gastrointestinal disorders. As an additional objective, the association between intestinal fructose malabsorption and food intake, including the estimated fructose consumption, weight, height, and lactulose fermentability were also studied. The study included 31 patients with abdominal pain (11 with functional dyspepsia, 10 with irritable bowel syndrome, and 10 with functional abdominal pain). The hydrogen breath test was used to investigate fructose malabsorption and lactulose fermentation in the intestinal lumen. Food consumption was assessed by food registry. Weight and height were measured. Fructose malabsorption was characterized in 21 (67.7%) patients (nine with irritable bowel syndrome, seven with functional abdominal pain, and five with functional dyspepsia). Intolerance after fructose administration was observed in six (28.6%) of the 21 patients with fructose malabsorption. Fructose malabsorption was associated with higher (pfructose intake by patients with and without fructose malabsorption were, respectively, 16.1 and 10.5g/day (p=0.087). Fructose malabsorption is associated with increased lactulose fermentability in the intestinal lumen. Body mass index was higher in patients with fructose malabsorption. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  17. Utility of dark-lumen MR colonography for the assessment of extra-colonic organs

    International Nuclear Information System (INIS)

    Ajaj, Waleed; Goyen, Mathias; Ruehm, Stefan G.; Ladd, Susanne C.; Gerken, Guido

    2007-01-01

    The aim of the study was to evaluate the utility of dark-lumen MR colonography (MRC) for the assessment of extra-colonic organs. Three hundred seventy-five subjects with suspected colonic disease underwent a complete MRC examination. MRC data were evaluated by two radiologists in a blinded fashion. In addition to the large bowel, the extra-intestinal organs from the lung bases to the pelvis were assessed for the presence of pathologies. All findings were divided into known or unknown findings and therapeutically relevant or irrelevant findings. If deemed necessary, other diagnostic imaging tests to further assess those findings were performed. In total, 510 extra-colonic findings were found in 260 (69%) of the 375 subjects. Known extra-colonic findings were found in 140 subjects (54%) and unknown findings in 120 subjects (46%). Thirty-one (12%) of the 260 subjects had therapeutically relevant findings (45 findings); 229 patients (88%) had irrelevant findings (465 findings). Dark-lumen MRC is a useful tool not only for the assessment of the entire colon, but also for the evaluation of extra-colonic organs. Thus, intra- and extra-colonic pathologies can be diagnosed within the same examination. (orig.)

  18. Pten facilitates epiblast epithelial polarization and proamniotic lumen formation in early mouse embryos.

    Science.gov (United States)

    Meng, Yue; Cai, Kathy Q; Moore, Robert; Tao, Wensi; Tse, Jeffrey D; Smith, Elizabeth R; Xu, Xiang-Xi

    2017-07-01

    Phosphatase and tensin homologue on chromosome 10 (Pten), a lipid phosphatase originally identified as a tumor-suppressor gene, regulates the phosphoinositol 3 kinase signaling pathway and impacts cell death and proliferation. Pten mutant embryos die at early stages of development, although the particular developmental deficiency and the mechanisms are not yet fully understood. We analyzed Pten mutant embryos in detail and found that the formation of the proamniotic cavity is impaired. Embryoid bodies derived from Pten-null embryonic stem cells failed to undergo cavitation, reproducing the embryonic phenotype in vitro. Analysis of embryoid bodies and embryos revealed a role of Pten in the initiation of the focal point of the epithelial rosette that develops into the proamniotic lumen, and in establishment of epithelial polarity to transform the amorphous epiblast cells into a polarized epithelium. We conclude that Pten is required for proamniotic cavity formation by establishing polarity for epiblast cells to form a rosette that expands into the proamniotic lumen, rather than facilitating apoptosis to create the cavity. Developmental Dynamics 246:517-530, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. PDX vacuum vessel stress analysis

    International Nuclear Information System (INIS)

    Nikodem, Z.D.

    1975-01-01

    A stress analysis of PDX vacuum vessel is described and the summary of results is presented. The vacuum vessel is treated as a toroidal shell of revolution subjected to an internal vacuum. The critical buckling pressure is calculated. The effects of the geometrical discontinuity at the juncture of toroidal shell head and cylindrical outside wall, and the concavity of the cylindrical wall are examined. An effect of the poloidal field coil supports and the vessel outside supports on the stress distribution in the vacuum vessel is determined. A method evaluating the influence of circular ports in the vessel wall on the stress level in the vessel is outlined

  20. Composite Overwrapped Pressure Vessel (COPV) Stress Rupture Testing

    Science.gov (United States)

    Greene, Nathanael J.; Saulsberry, Regor L.; Leifeste, Mark R.; Yoder, Tommy B.; Keddy, Chris P.; Forth, Scott C.; Russell, Rick W.

    2010-01-01

    This paper reports stress rupture testing of Kevlar(TradeMark) composite overwrapped pressure vessels (COPVs) at NASA White Sands Test Facility. This 6-year test program was part of the larger effort to predict and extend the lifetime of flight vessels. Tests were performed to characterize control parameters for stress rupture testing, and vessel life was predicted by statistical modeling. One highly instrumented 102-cm (40-in.) diameter Kevlar(TradeMark) COPV was tested to failure (burst) as a single-point model verification. Significant data were generated that will enhance development of improved NDE methods and predictive modeling techniques, and thus better address stress rupture and other composite durability concerns that affect pressure vessel safety, reliability and mission assurance.

  1. In vitro fabrication of functional three-dimensional tissues with perfusable blood vessels.

    Science.gov (United States)

    Sekine, Hidekazu; Shimizu, Tatsuya; Sakaguchi, Katsuhisa; Dobashi, Izumi; Wada, Masanori; Yamato, Masayuki; Kobayashi, Eiji; Umezu, Mitsuo; Okano, Teruo

    2013-01-01

    In vitro fabrication of functional vascularized three-dimensional tissues has been a long-standing objective in the field of tissue engineering. Here we report a technique to engineer cardiac tissues with perfusable blood vessels in vitro. Using resected tissue with a connectable artery and vein as a vascular bed, we overlay triple-layer cardiac cell sheets produced from coculture with endothelial cells, and support the tissue construct with media perfused in a bioreactor. We show that endothelial cells connect to capillaries in the vascular bed and form tubular lumens, creating in vitro perfusable blood vessels in the cardiac cell sheets. Thicker engineered tissues can be produced in vitro by overlaying additional triple-layer cell sheets. The vascularized cardiac tissues beat and can be transplanted with blood vessel anastomoses. This technique may create new opportunities for in vitro tissue engineering and has potential therapeutic applications.

  2. Evaluation of the normal thoracic and abdominal aorta diameters by computerized tomography

    International Nuclear Information System (INIS)

    Lucarelli, Claudio Luiz

    1995-01-01

    The study was undertaken to evaluate, through computerized tomography, the diameters of the normal thoracic and abdominal aorta, as well as they are connected to gender, age and body surface area; and the ratio between measurements obtained at the ascending and descending limbs of the thoracic aorta, and between the abdominal aortic diameters. For that reason, we measured the widest anteroposterior diameters of the thoracic aortas at the levels of the arch, the root, the pulmonary artery, and the thoracic-abdominal transition, as well as the level of the emergence of the superior mesenteric artery, of the renal hila and just cephalad to the bifurcation of the abdominal aortas of 350 patients without cardiovascular diseases who had undergone computerized tomography of the thorax and/or abdomen for any other reasons. Observation and statistic analyses led us to conclude that: 1) both the thoracic and abdominal aortic diameters are reduced from their proximal to their distal portions; 2) the body surface influences the size of the aorta, although only extreme variations alter the vessel's caliber; 3) vessel diameter was observed to gradually increase with age; 4) men were found to have larger diameters than age matched women; 5) the ratio between the ascending and descending aortic diameters varies according to gender and age; 6) the relations between abdominal aortic diameters measured at the level of renal hila and cephalad to the bifurcation are independent from gender and age. But the relation between those measured at the level of the superior mesenteric artery and cephalad to the bifurcation are linked to gender, but not to age. (author)

  3. Intracranial arterial aneurysm vasculopathies: targeting the outer vessel wall

    International Nuclear Information System (INIS)

    Krings, Timo; Piske, Ronie L.; Lasjaunias, Pierre L.

    2005-01-01

    The pathogenesis of intracranial arterial aneurysms (AA) remains unclear, despite their clinical importance. An improved understanding of this disease is important in choosing therapeutic options. In addition to the ''classical'' berry-type aneurysm, there are various other types of intracranial AA such as infectious, dissecting or giant, partially-thrombosed aneurysms. From the clinician's perspective, the hypothesis that some of these intracranial AA might be due to abluminal factors has been proposed for several years. Indeed, this hypothesis and the empirical use of anti-inflammatory drugs in giant intracranial aneurysms have been confirmed by recent studies reporting that an enzyme involved in the inflammatory cascade (5-lipoxygenase or 5-LO) promotes the pathogenesis of specific aneurysms in humans. 5-LO generates different forms of leukotrienes which are potent mediators of inflammation. Adventitial inflammation leads to a weakening of the media from the abluminal part of the vessel wall due to the release of proinflammatory factors that invade the media, thereby degrading the extracellular matrix, the elastic lamina of the vascular wall, and, finally, the integrity of the vessel lumen. This in turn results in a dilation of the vessel and aneurysm formation. Moreover, neoangiogenesis of vasa vasorum is found in close proximity to 5-LO activated macrophages. In addition to this biological cascade, we argue that repeated subadventitial haemorrhages from the new vasa vasorum play an important role in aneurysm pathogenesis, due to a progressive increase in size mediated by the apposition of new layers of intramural haematoma within the vessel wall. Intracranial giant AA can therefore be regarded as a proliferative disease of the vessel wall induced by extravascular activity. (orig.)

  4. Effective diameters and corresponding states of fluids

    Science.gov (United States)

    Del Río, Fernando

    Effective hard-sphere diameters of fluids with purely repulsive interactions are derived from a generalized corresponding-states principle of Leland, Rowlinson and coworkers. Various alternative definitions are discussed and related. Virial expansions of the effective diameters and their corresponding volumes are obtained and compared with results of perturbation theory. Applications are made to inverse-power potentials, the repulsive part of the Lennard-Jones potential and hard spherocylinders and dumbells.

  5. Appendiceal diameter: CT versus sonographic measurements

    Energy Technology Data Exchange (ETDEWEB)

    Orscheln, Emily S. [University of Cincinnati Medical Center, Department of Radiology, Cincinnati, OH (United States); Trout, Andrew T. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2016-03-15

    Ultrasound and CT are the dominant imaging modalities for assessment of suspected pediatric appendicitis, and the most commonly applied diagnostic criterion for both modalities is appendiceal diameter. The classically described cut-off diameter for the diagnosis of appendicitis is 6 mm when using either imaging modality. To demonstrate the fallacy of using the same cut-off diameter for both CT and US in the diagnosis of appendicitis. We conducted a retrospective review of patients younger than 18 years who underwent both US and CT of the appendix within 24 h. The shortest transverse dimension of the appendix was measured at the level of the proximal, mid and distal appendix on US and CT images. We compared mean absolute difference in appendiceal diameter between US and CT, using the paired t-test. We reviewed exams of 155 children (58.7% female) with a mean age of 11.3 ± 4.2 years; 38 of the children (24.5%) were diagnosed with appendicitis. The average time interval between US and CT was 7.0 ± 5.4 h. Mean appendiceal diameter measured by CT was significantly larger than that measured by US in cases without appendicitis (5.3 ± 1.0 mm vs. 4.7 ± 1.1 mm, P < 0.0001) and in cases with appendicitis (8.3 ± 2.2 mm vs. 7.0 ± 2.0 mm, P < 0.0001). Mean absolute diameter difference at any location along the appendix was 1.3-1.4 mm in normal appendices and 2 mm in cases of appendicitis. Measured appendiceal diameter differs between US and CT by 1-2 mm, calling into question use of the same diameter cut-off (6 mm) for both modalities for the diagnosis of appendicitis. (orig.)

  6. Bijective Diameters of Gene Tree Parsimony Costs.

    Science.gov (United States)

    Gorecki, Pawel; Eulenstein, Oliver

    2017-08-04

    Synthesizing median trees from a collection of gene trees under the biologically motivated gene tree parsimony (GTP) costs has provided credible species tree estimates. GTP costs are defined for each of the classic evolutionary processes. These costs count the minimum number of events necessary to reconcile the gene tree with the species tree where the leaf-genes are mapped to the leaf-species through a function called labeling. To better understand the synthesis of median trees under these costs there is an increased interest in analyzing their diameters. The diameters of a GTP cost between a gene tree and a species tree are the maximum values of this cost of one or both topologies of the trees involved. We are concerned about the diameters of the GTP costs under bijective labelings. While these diameters are linear time computable for the gene duplication and deep coalescence costs, this has been unknown for the classic gene duplication and loss, and for the loss cost. For the first time, we show how to compute these diameters and proof that this can be achieved in linear time, and thus, completing the computational time analysis for all of the bijective diameters under the GTP costs.

  7. Preparation of lumen-loaded kenaf pulp with magnetite (Fe{sub 3}O{sub 4})

    Energy Technology Data Exchange (ETDEWEB)

    Zakaria, S.; Ong, B.H.; Ahmad, S.H.; Abdullah, M.; Yamauchi, T

    2005-02-15

    Magnetic pulps were prepared from unbleached kenaf (hibiscus cannabinus L.) kraft pulps. Fe{sub 3}O{sub 4} or magnetite powder was used to load into the pulp's lumen and pit. Aluminum sulphate [Al{sub 2}(SO{sub 4}){sub 3}] (alum) and polyethylenimine (PEI), both mainly function as retention aid were used throughout the experiment and found to be beneficial in the preparation of this magnetic pulps. The ash content method was used to determine the amount of magnetite retained in the lumen and pit. The utilization of PEI up to 2% per pulp fibres was found to be the best result on lumen loading. The deposition of magnetite powder in lumen and pit is found decrease as the addition of PEI used is more than 2% per pulp fibres. Scanning electron microscope (SEM) clearly shows the distribution of magnetite deposited in the lumen. Tensile index and folding endurance of the loaded fibre decreased slightly as the percentage of loading pigment increased.

  8. Src- and Fyn-dependent apical membrane trafficking events control endothelial lumen formation during vascular tube morphogenesis.

    Science.gov (United States)

    Kim, Dae Joong; Norden, Pieter R; Salvador, Jocelynda; Barry, David M; Bowers, Stephanie L K; Cleaver, Ondine; Davis, George E

    2017-01-01

    Here we examine the question of how endothelial cells (ECs) develop their apical membrane surface domain during lumen and tube formation. We demonstrate marked apical membrane targeting of activated Src kinases to this apical domain during early and late stages of this process. Immunostaining for phosphotyrosine or phospho-Src reveals apical membrane staining in intracellular vacuoles initially. This is then followed by vacuole to vacuole fusion events to generate an apical luminal membrane, which is similarly decorated with activated phospho-Src kinases. Functional blockade of Src kinases completely blocks EC lumen and tube formation, whether this occurs during vasculogenic tube assembly or angiogenic sprouting events. Multiple Src kinases participate in this apical membrane formation process and siRNA suppression of Src, Fyn and Yes, but not Lyn, blocks EC lumen formation. We also demonstrate strong apical targeting of Src-GFP and Fyn-GFP fusion proteins and increasing their expression enhances lumen formation. Finally, we show that Src- and Fyn-associated vacuoles track and fuse along a subapically polarized microtubule cytoskeleton, which is highly acetylated. These vacuoles generate the apical luminal membrane in a stereotypically polarized, perinuclear position. Overall, our study identifies a critical role for Src kinases in creating and decorating the EC apical membrane surface during early and late stages of lumen and tube formation, a central event in the molecular control of vascular morphogenesis.

  9. Src- and Fyn-dependent apical membrane trafficking events control endothelial lumen formation during vascular tube morphogenesis.

    Directory of Open Access Journals (Sweden)

    Dae Joong Kim

    Full Text Available Here we examine the question of how endothelial cells (ECs develop their apical membrane surface domain during lumen and tube formation. We demonstrate marked apical membrane targeting of activated Src kinases to this apical domain during early and late stages of this process. Immunostaining for phosphotyrosine or phospho-Src reveals apical membrane staining in intracellular vacuoles initially. This is then followed by vacuole to vacuole fusion events to generate an apical luminal membrane, which is similarly decorated with activated phospho-Src kinases. Functional blockade of Src kinases completely blocks EC lumen and tube formation, whether this occurs during vasculogenic tube assembly or angiogenic sprouting events. Multiple Src kinases participate in this apical membrane formation process and siRNA suppression of Src, Fyn and Yes, but not Lyn, blocks EC lumen formation. We also demonstrate strong apical targeting of Src-GFP and Fyn-GFP fusion proteins and increasing their expression enhances lumen formation. Finally, we show that Src- and Fyn-associated vacuoles track and fuse along a subapically polarized microtubule cytoskeleton, which is highly acetylated. These vacuoles generate the apical luminal membrane in a stereotypically polarized, perinuclear position. Overall, our study identifies a critical role for Src kinases in creating and decorating the EC apical membrane surface during early and late stages of lumen and tube formation, a central event in the molecular control of vascular morphogenesis.

  10. Vessels in Transit - Web Tool

    Data.gov (United States)

    Department of Transportation — A web tool that provides real-time information on vessels transiting the Saint Lawrence Seaway. Visitors may sort by order of turn, vessel name, or last location in...

  11. Radiant vessel auxiliary cooling system

    Science.gov (United States)

    Germer, John H.

    1987-01-01

    In a modular liquid-metal pool breeder reactor, a radiant vessel auxiliary cooling system is disclosed for removing the residual heat resulting from the shutdown of a reactor by a completely passive heat transfer system. A shell surrounds the reactor and containment vessel, separated from the containment vessel by an air passage. Natural circulation of air is provided by air vents at the lower and upper ends of the shell. Longitudinal, radial and inwardly extending fins extend from the shell into the air passage. The fins are heated by radiation from the containment vessel and convect the heat to the circulating air. Residual heat from the primary reactor vessel is transmitted from the reactor vessel through an inert gas plenum to a guard or containment vessel designed to contain any leaking coolant. The containment vessel is conventional and is surrounded by the shell.

  12. Attachment Fitting for Pressure Vessel

    Science.gov (United States)

    Smeltzer, Stanley S., III (Inventor); Carrigan, Robert W. (Inventor)

    2002-01-01

    This invention provides sealed access to the interior of a pressure vessel and consists of a tube. a collar, redundant seals, and a port. The port allows the seals to be pressurized and seated before the pressure vessel becomes pressurized.

  13. Confinement Vessel Assay System: Design and Implementation Report

    Energy Technology Data Exchange (ETDEWEB)

    Frame, Katherine C. [Los Alamos National Laboratory; Bourne, Mark M. [Los Alamos National Laboratory; Crooks, William J. [Los Alamos National Laboratory; Evans, Louise [Los Alamos National Laboratory; Mayo, Douglas R. [Los Alamos National Laboratory; Gomez, Cipriano D. [Retired CMR-OPS: OPERATIONS; Miko, David K. [Los Alamos National Laboratory; Salazar, William R. [Los Alamos National Laboratory; Stange, Sy [Los Alamos National Laboratory; Vigil, Georgiana M. [Los Alamos National Laboratory

    2012-07-18

    Los Alamos National Laboratory has a number of spherical confinement vessels remaining from tests involving nuclear materials. These vessels have an inner diameter of 6 feet with 1- to 2-inch thick steel walls. The goal of the Confinement Vessel Disposition (CVD) project is to remove debris and reduce contamination inside the vessels. We have developed a neutron assay system for the purposes of Materials Control and Accountability (MC&A) measurements of the vessel prior to and after cleanout. We present our approach to confronting the challenges in designing, building, and testing such a system. The system was designed to meet a set of functional and operational requirements. A Monte Carlo model was developed to aid in optimizing the detector design as well as to predict the systematic uncertainty associated with confinement vessel measurements. Initial testing was performed to optimize and determine various measurement parameters, and then the system was characterized using {sup 252}Cf placed a various locations throughout the measurement system. Measurements were also performed with a {sup 252}Cf source placed inside of small steel and HDPE shells to study the effect of moderation. These measurements compare favorably with their MCNPX model equivalent, making us confident that we can rely on the Monte Carlo simulation to predict the systematic uncertainty due to variations in response to material that may be localized at different points within a vessel.

  14. Axial vessel widening in arborescent monocots.

    Science.gov (United States)

    Petit, Giai; DeClerck, Fabrice A J; Carrer, Marco; Anfodillo, Tommaso

    2014-02-01

    Dicotyledons have evolved a strategy to compensate for the increase in hydraulic resistance to water transport with height growth by widening xylem conduits downwards. In monocots, the accumulation of hydraulic resistance with height should be similar, but the absence of secondary growth represents a strong limitation for the maintenance of xylem hydraulic efficiency during ontogeny. The hydraulic architecture of monocots has been studied but it is unclear how monocots arrange their axial vascular structure during ontogeny to compensate for increases in height. We measured the vessel lumina and estimated the hydraulic diameter (Dh) at different heights along the stem of two arborescent monocots, Bactris gasipaes (Kunth) and Guadua angustifolia (Kunth). For the former, we also estimated the variation in Dh along the leaf rachis. Hydraulic diameter increased basally from the stem apex to the base with a scaling exponent (b) in the range of those reported for dicot trees (b = 0.22 in B. gasipaes; b = 0.31 and 0.23 in G. angustifolia). In B. gasipaes, vessels decrease in Dh from the stem's centre towards the periphery, an opposite pattern compared with dicot trees. Along the leaf rachis, a pattern of increasing Dh basally was also found (b = 0.13). The hydraulic design of the monocots studied revealed an axial pattern of xylem conduits similar to those evolved by dicots to compensate and minimize the negative effect of root-to-leaf length on hydrodynamic resistance to water flow.

  15. Mobile nuclear reactor containment vessel

    International Nuclear Information System (INIS)

    Thompson, R.E.; Spurrier, F.R.; Jones, A.R.

    1978-01-01

    A containment vessel for use in mobile nuclear reactor installations is described. The containment vessel completely surrounds the entire primary system, and is located as close to the reactor primary system components as is possible in order to minimize weight. In addition to being designed to withstand a specified internal pressure, the containment vessel is also designed to maintain integrity as a containment vessel in case of a possible collision accident

  16. Dual-Lumen Chest Port Infection Rates in Patients with Head and Neck Cancer

    International Nuclear Information System (INIS)

    Bos, Aaron; Ahmed, Osman; Jilani, Danial; Giger, Maryellen; Funaki, Brian S.; Zangan, Steven M.

    2015-01-01

    PurposeThe aim of this study was to investigate dual-lumen chest port infection rates in patients with head and neck cancer (HNC) compared to those with other malignancies (non-HNC).Materials and MethodsAn IRB-approved retrospective study was performed on 1,094 consecutive chest ports placed over a 2-year period. Patients with poor follow-up (n = 53), no oncologic history (n = 13), or single-lumen ports (n = 183) were excluded yielding a study population of 845 patients. The electronic medical records were queried for demographic information, data regarding ports and infections, and imaging review.ResultsHNC patients experienced more infections (42 vs. 30), an increased infection rate per 1,000 catheter days (0.68 vs. 0.21), and more early infections within 30 days compared to non-HNC patients (10 vs. 6) (p < 0.001, p < 0.001, p = 0.02, respectively). An existing tracheostomy at the time of port placement was associated with infection in the HNC group (p = 0.02) but was not an independent risk factor for infection in the study population overall (p = 0.06). There was a significant difference in age, male gender, and right-sided ports between the HNC and non-HNC groups (p < 0.01, p < 0.001, and p = 0.01), although these were not found to be independent risk factors for infection (p = 0.32, p = 0.76, p = 0.16).ConclusionHNC patients are at increased risk for infection of dual-lumen chest ports placed via a jugular approach compared to patients with other malignancies. Tracheostomy is associated with infection in HNC patients but is not an independent risk factor for infection in the oncologic population as a whole

  17. Dual-Lumen Chest Port Infection Rates in Patients with Head and Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Bos, Aaron, E-mail: abos1210@gmail.com; Ahmed, Osman [University of Chicago Medical Center (United States); Jilani, Danial [Wright State University Boonshoft School of Medicine (United States); Giger, Maryellen; Funaki, Brian S.; Zangan, Steven M. [University of Chicago Medical Center (United States)

    2015-06-15

    PurposeThe aim of this study was to investigate dual-lumen chest port infection rates in patients with head and neck cancer (HNC) compared to those with other malignancies (non-HNC).Materials and MethodsAn IRB-approved retrospective study was performed on 1,094 consecutive chest ports placed over a 2-year period. Patients with poor follow-up (n = 53), no oncologic history (n = 13), or single-lumen ports (n = 183) were excluded yielding a study population of 845 patients. The electronic medical records were queried for demographic information, data regarding ports and infections, and imaging review.ResultsHNC patients experienced more infections (42 vs. 30), an increased infection rate per 1,000 catheter days (0.68 vs. 0.21), and more early infections within 30 days compared to non-HNC patients (10 vs. 6) (p < 0.001, p < 0.001, p = 0.02, respectively). An existing tracheostomy at the time of port placement was associated with infection in the HNC group (p = 0.02) but was not an independent risk factor for infection in the study population overall (p = 0.06). There was a significant difference in age, male gender, and right-sided ports between the HNC and non-HNC groups (p < 0.01, p < 0.001, and p = 0.01), although these were not found to be independent risk factors for infection (p = 0.32, p = 0.76, p = 0.16).ConclusionHNC patients are at increased risk for infection of dual-lumen chest ports placed via a jugular approach compared to patients with other malignancies. Tracheostomy is associated with infection in HNC patients but is not an independent risk factor for infection in the oncologic population as a whole.

  18. Spent fuel transporting vessel

    International Nuclear Information System (INIS)

    Kumagaya, Takeshi.

    1995-01-01

    A large number of annular cooling fins are disposed each at an equal distance on the outer circumferential surface of a vessel main body. An electric power generation module is disposed on the surface of the cooling fins. The electric power generation module comprises a plurality of thermoelectric power generation elements. In each of the thermoelectric generation elements, the inner side thereof in contact with the surface of the cooling fin is at a high temperature while the outer side thereof is at a low temperature nearly equal with an atmospheric temperature. A predetermined amount of electric power is generated by seebeck effect due to the temperature difference. The electric power is always stored in a battery. Accordingly, even if a power generator of a ship should fail and power supply is stopped during transportation of the vessels for spent nuclear fuels, an appropriate amount of electric power can be supplied to a cooling device of the ship. (I.N.)

  19. Reactor vessel sealing plug

    International Nuclear Information System (INIS)

    Dooley, R.A.

    1986-01-01

    An apparatus is described for sealing a cold leg nozzle of a nuclear reactor pressure vessel from a remote location comprising: at least one sealing plug for mechanically sealing the nozzle from the inside of the reactor pressure vessel. The sealing plug includes a plate and a cone assembly having an end part receptive in the nozzle, the plate being axially moveable relative to the cone assembly. The plate and cone assembly have confronting bevelled edges defining an opening therebetween. A primary O-ring is disposed about the opening and is supported on the bevelled edges, the plate being guidably mounted to the cone assembly for movement toward the cone assembly to radially expand the primary O-ring into sealing engagement with the nozzle. A means is included for providing relative movement between the outer plate and the cone assembly

  20. Reactor Pressure Vessel Steels

    Energy Technology Data Exchange (ETDEWEB)

    Van de Velde, J.; Fabry, A.; Van Walle, E.; Chaoudi, R

    1998-07-01

    SCK-CEN's R and D programme on Reactor Pressure Vessel (RPV) Steels in performed in support of the RVP integrity assessment. Its main objectives are: (1) to develop enhanced surveillance concepts by applying micromechanics and fracture-toughness tests to small specimens, and by performing damage modelling and microstructure characterization; (2) to demonstrate the applied methodology on a broad database; (3) to achieve regulatory acceptance and industrial use. Progress and achievements in 1999 are reported.

  1. High pressure storage vessel

    Science.gov (United States)

    Liu, Qiang

    2013-08-27

    Disclosed herein is a composite pressure vessel with a liner having a polar boss and a blind boss a shell is formed around the liner via one or more filament wrappings continuously disposed around at least a substantial portion of the liner assembly combined the liner and filament wrapping have a support profile. To reduce susceptible to rupture a locally disposed filament fiber is added.

  2. Geometric Deformations of the Thoracic Aorta and Supra-Aortic Arch Branch Vessels Following Thoracic Endovascular Aortic Repair.

    Science.gov (United States)

    Ullery, Brant W; Suh, Ga-Young; Hirotsu, Kelsey; Zhu, David; Lee, Jason T; Dake, Michael D; Fleischmann, Dominik; Cheng, Christopher P

    2018-04-01

    To utilize 3-D modeling techniques to better characterize geometric deformations of the supra-aortic arch branch vessels and descending thoracic aorta after thoracic endovascular aortic repair. Eighteen patients underwent endovascular repair of either type B aortic dissection (n = 10) or thoracic aortic aneurysm (n = 8). Computed tomography angiography was obtained pre- and postprocedure, and 3-D geometric models of the aorta and supra-aortic branch vessels were constructed. Branch angle of the supra-aortic branch vessels and curvature metrics of the ascending aorta, aortic arch, and stented thoracic aortic lumen were calculated both at pre- and postintervention. The left common carotid artery branch angle was lower than the left subclavian artery angles preintervention ( P Supra-aortic branch vessel angulation remains relatively static when proximal landing zones are distal to the left common carotid artery.

  3. Ionizing radiations and blood vessels

    International Nuclear Information System (INIS)

    Vorob'ev, E.I.; Stepanov, R.P.

    1985-01-01

    Data on phenomenology of radiation-induced changes in blood vessels are systematized and authors' experience is generalized. Modern concepts about processes leading to vessel structure injury after irradiation is critically analyzed. Special attention is paid to reparation and compensation of X-ray vessel injury, consideration of which is not yet sufficiently elucidated in literature

  4. Ionizing radiations and blood vessels

    International Nuclear Information System (INIS)

    Vorob'ev, E.I.; Stepanov, R.P.

    1985-01-01

    Data on phenomeology of radiation changes of blood vessels are systemized and the authors' experience is generalyzed. A critical analysis of modern conceptions on processes resulting in vessel structure damage after irradiation, is given. Special attention is paid to reparation and compensation of radiation injury of vessels

  5. Fabrication of mercury target vessel

    International Nuclear Information System (INIS)

    Wakui, Takashi; Kogawa, Hiroyuki; Haga, Katsuhiro; Futakawa, Masatoshi; Hayashi, Ryoichi; Uchiyama, Naoyoshi; Okamoto, Yoshinao; Nakamura, Koji

    2010-03-01

    The construction of materials and life science experimental facility in J-PARC (Japan Proton Accelerator Complex) project had been completed and accepted pulsed proton beams with low power. Since 2003, the detailed design, fabrication and examination for the mercury target vessel as a pulsed neutron source were carried out by the vender. The mercury target vessel consists of triple-walled structure in order to prevent the leak of mercury to outside at the failure of the mercury vessel and to remove the heat of the safety hull, which covers the mercury vessel, due to the injection of the pulsed proton beams. The high fabrication accuracy is required for the mercury target vessel assembled by the welding, because there are the relationships between the mercury target vessel and other components (target trolley, target storage container, flange of helium vessel, reflector and water-cooled shield). At each fabrication step, the examinations for the mercury target vessel with multi-walled structure were required. In this report, the required specification and basic structure of parts in the mercury target vessel are described and the fabrication procedure of the mercury target vessel by the vender is reported. In the fabrication of the mercury target vessel, there were many troubles such as large deformation due to the welding and then the vender repaired and brought the mercury target vessel to completion. Furthermore, improvements for the design and fabrication of the mercury target are reported. (author)

  6. Inservice inspection of Halden BWR pressure vessel

    International Nuclear Information System (INIS)

    Foerli, O.; Hernes, T.

    1978-01-01

    A description is given of how the recertification inspection of the 20 years old Halden Reactor pressure vessel was carried out in accordance with the latest ASME-CODES, despite the fact that inspection accessibility was poor. As no volumetric inspection had been carried out since the preservice radiography in 1957, the ultrasonic inspection included the high flux region of all welds. In total 70% of longitudinal welds and 20% of bottom circumferential welds were inspected as well as the bottom nozzle connection. The vessel was not designed with provisions for inservice inspection, the welds are unaccessible from the outside and removal of the lid is virtually impossible. The ultrasonic probes could only be loaded through 77 mm diameter holes in the top lid and remotely positioned inside the vessel. The inspection was performed using 450C and 60OC 1 MHz angle probes and 2.25 MHz normal probes in immersion technique. In a zone around the welds, small regions with lack of bonding between the stainless steel cladding and the boiler steel were revealed. One root defect known and accepted from the preservice radiographs was examined. The defect was found to be 6x30mm as a maximum and well within acceptable limits according to the fracture mechanics analysis method recommended in ASME X1. The inspection required a period of three weeks' work in the reactor hall. (UK)

  7. Further understanding of PbWO4 Scintillator characteristics and their optimisation. LUMEN activity in 1998

    CERN Document Server

    Baccaro, Stefania; Borgia, Bruno; Cecilia, Angelica; Dafinei, Ioan; Diemoz, Marcella; Fabeni, P; Festinesi, Armando; Longo, Egidio; Martini, M; Meinardi, F; Mihoková, E; Montecchi, Marco; Nikl, M; Pazzi, G P; Rosa, J; Sulc, Miroslav

    2000-01-01

    The aim of LUMEN collaboration was the investigation on single crystals of PbWO4 ( PWO): the results performed up to now provide the evidence of the possibility to optimise the optical properties of an intrinsic scintillator such as PWO. The control of essential requirements in the crystal preparation ( raw material purity, growing methods and post-growth annealing) as well as the introduction of selected dopants at suitable concentrations ( particularly trivalent and pentavalent ions) were found to be very successful in lowering the concentration of point defects in the lattice which strongly affect scintillation properties and radiation hardness. The systematic investigation effort to better understand the scintillation characteristics and to improve the quality of PWO crystals is due to their use for the CMS electromagnetic calorimeter.

  8. Subadventitial techniques for chronic total occlusion percutaneous coronary intervention: The concept of "vessel architecture".

    Science.gov (United States)

    Azzalini, Lorenzo; Carlino, Mauro; Brilakis, Emmanouil S; Vo, Minh; Rinfret, Stéphane; Uretsky, Barry F; Karmpaliotis, Dimitri; Colombo, Antonio

    2018-03-01

    Despite improvements in guidewire technologies, the traditional antegrade wire escalation approach to chronic total occlusion (CTO) recanalization is successful in only 60-80% of selected cases. In particular, long, calcified, and tortuous occlusions are less successfully approached with a true-to-true lumen approach. Frequently, the guidewire tracks into the subadventitial space, with no guarantee of distal re-entry into the true lumen. The ability to manage the subadventitial space has been a key step in the tremendous improvement in success rates of contemporary CTO percutaneous coronary intervention (PCI), whether operating antegradely or retrogradely. A modern approach to CTO PCI involves understanding the concept of "vessel architecture," which is based on the distinction between coronary structures (occlusive plaque, comprising the disrupted intima and media, and the outer adventitia) and extravascular space. The vessel architecture represents a safe work environment for guidewire and device manipulation. This review provides an anatomy-based description of the concept of vessel architecture, along with a historical perspective of subadventitial techniques for CTO PCI, and outcome data of CTO PCI utilizing the subadventitial space. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  9. Peptidases Compartmentalized to the Ascaris suum Intestinal Lumen and Apical Intestinal Membrane

    Science.gov (United States)

    Rosa, Bruce A.

    2015-01-01

    The nematode intestine is a tissue of interest for developing new methods of therapy and control of parasitic nematodes. However, biological details of intestinal cell functions remain obscure, as do the proteins and molecular functions located on the apical intestinal membrane (AIM), and within the intestinal lumen (IL) of nematodes. Accordingly, methods were developed to gain a comprehensive identification of peptidases that function in the intestinal tract of adult female Ascaris suum. Peptidase activity was detected in multiple fractions of the A. suum intestine under pH conditions ranging from 5.0 to 8.0. Peptidase class inhibitors were used to characterize these activities. The fractions included whole lysates, membrane enriched fractions, and physiological- and 4 molar urea-perfusates of the intestinal lumen. Concanavalin A (ConA) was confirmed to bind to the AIM, and intestinal proteins affinity isolated on ConA-beads were compared to proteins from membrane and perfusate fractions by mass spectrometry. Twenty-nine predicted peptidases were identified including aspartic, cysteine, and serine peptidases, and an unexpectedly high number (16) of metallopeptidases. Many of these proteins co-localized to multiple fractions, providing independent support for localization to specific intestinal compartments, including the IL and AIM. This unique perfusion model produced the most comprehensive view of likely digestive peptidases that function in these intestinal compartments of A. suum, or any nematode. This model offers a means to directly determine functions of these proteins in the A. suum intestine and, more generally, deduce the wide array functions that exist in these cellular compartments of the nematode intestine. PMID:25569475

  10. Analysis of the intestinal lumen microbiota in an animal model of colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Qingchao Zhu

    Full Text Available Recent reports have suggested that multiple factors such as host genetics, environment and diet can promote the progression of healthy mucosa towards sporadic colorectal carcinoma. Accumulating evidence has additionally associated intestinal bacteria with disease initiation and progression. In order to examine and analyze the composition of gut microbiota in the absence of confounding influences, we have established an animal model of 1, 2-dimethylhydrazine (DMH-induced colon cancer. Using this model, we have performed pyrosequencing of the V3 region of the 16S rRNA genes in this study to determine the diversity and breadth of the intestinal microbial species. Our findings indicate that the microbial composition of the intestinal lumen differs significantly between control and tumor groups. The abundance of Firmicutes was elevated whereas the abundance of Bacteroidetes and Spirochetes was reduced in the lumen of CRC rats. Fusobacteria was not detected in any of the healthy rats and there was no significant difference in observed Proteobacteria species when comparing the bacterial communities between our two groups. Interestingly, the abundance of Proteobacteria was higher in CRC rats. At the genus level, Bacteroides exhibited a relatively higher abundance in CRC rats compared to controls (14.92% vs. 9.22%, p<0.001. Meanwhile, Prevotella (55.22% vs. 26.19%, Lactobacillus (3.71% vs. 2.32% and Treponema (3.04% vs. 2.43%, were found to be significantly more abundant in healthy rats than CRC rats (p<0.001, respectively. We also demonstrate a significant reduction of butyrate-producing bacteria such as Roseburia and Eubacterium in the gut microbiota of CRC rats. Furthermore, a significant increase in Desulfovibrio, Erysipelotrichaceae and Fusobacterium was also observed in the tumor group. A decrease in probiotic species such as Ruminococcus and Lactobacillus was likewise observed in the tumor group. Collectively, we can conclude that a significant

  11. Double-lumen endotracheal tube positioning: Bag compliance Vs. fiberoptic bronchoscopy

    Directory of Open Access Journals (Sweden)

    Noyan Ashraf MA

    2012-11-01

    Full Text Available Background: Lung separation is the basis of thoracic anesthesia, which is performed by different instruments. Checking probable malpositioning of tracheal tube needs fiberoptic bronchoscopy. The aim of this study was to compare respirator suggested compliance with fiberoptic findings in detecting major tracheal tube malpositioning.Methods: A total of 256 patients undergoing thoracic surgery with double-lumen tracheal tube insertion in Imam Khomeini Hospital, Tehran, Iran, during 2010-11 were divided into three groups (n=86. We used left-sided double-lumen tube (DLT for left or right-sided surgeries (groups 1 and 2, and right-sided DLT for left-sided surgeries (group 3. The position of the tubes was evaluated and compared using bag compliance versus fiberoptic bronchoscopy.Results: The mean age of the study population was 44.7±13.4 (16-73 years, while 155 (59.9% were male. The sensitivity, specificity, positive and negative predictive values, and the accuracy of bag compliance test for left-sided DLT in supine position were 40% (95% CI: 20-60%, 99% (95% CI: 96-99%, 84% (95% CI: 54-94% 92% (95% CI: 88-95% and 92% (95% CI: 87-95%, respectively. The above-mentioned variables for lateral decubitus position respectively were 27%, 98%, 76%, 89%, and 88%. Malpositioning was more prevalent in right-sided DLTs (P=0.02.Conclusion: Based on the results of this study, and the high specificity, positive predictive value, and accuracy of bag compliance test, its use is encouraged as an alternative to fiberoptic bronchoscopy for checking DLT position, specially, in emergent surgeries or when fiberoptic bronchoscopy is unreachable due to lack of expertise or personnel.

  12. Inactivation of Bacteria on Explanted Dialysis Catheter Lumens with Fiber Optically Delivered Ultraviolet Light.

    Science.gov (United States)

    Lin, Roger C; Prologo, J David

    2015-12-01

    To evaluate the germicidal effect of fiber optically delivered ultraviolet (UV) light on colonized explanted dialysis catheters. Explanted dialysis catheters were screened for intraluminal colonization by culturing 1 mL of a saline flush. Catheters growing >10 colony-forming units were treated with doses of fiber optically delivered UV light (range, 40-1,300 mJ/cm2). For each UV-treated catheter, an unexposed segment was first cut and set aside as a control sample. A sterile optical fiber was inserted into the catheter hub and advanced to the catheter tip. The fiber was slowly withdrawn at a constant rate while exposing the inner lumen to UV light. A second UV-exposed segment was then removed. The UV-exposed and control segments were split and sonicated to remove the adherent bacteria. The bacteria were counted and identified. There were 14 colonized catheters treated with UV light. The catheters were primarily colonized with coagulase-negative staphylococci (60%) and Staphylococcus aureus (33%). There was a significant reduction in viable bacteria between the UV-treated versus untreated segments of each infected catheter (P = .04). In the seven treated catheters with >100,000 colony-forming units per cm2 of luminal surface area, there was a >99.5% reduction of viable bacteria in all UV-exposed samples, with no residual viable bacteria in four of seven (57%) of the samples. This study demonstrates the technical feasibility and benchtop efficacy of using fiber optics to deliver UV light into the lumen of a colonized dialysis catheter and inactivating bacteria on the intraluminal surface. Copyright © 2015 SIR. Published by Elsevier Inc. All rights reserved.

  13. Directed growth of diameter-tunable nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Ozturk, Birol; Talukdar, Ishan; Flanders, Bret N [Department of Physics, Oklahoma State University, 145 Physical Sciences II, Stillwater, OK 74078 (United States)

    2007-09-12

    This study characterizes a method for controlling the nanowire diameter in the directed electrochemical nanowire assembly technique, where alternating voltages applied to electrodes in simple salt solutions induce the crystallization of metallic wires. Dendritic solidification is identified as an important component of this technique. A characteristic of dendritic solidification is that the growth velocity and tip radius are anti-correlated. This relationship is exploited here to realize diameter-tunable nanowire growth. The experimental parameter that provides this control is {omega}, the frequency of the alternating voltage. Increasing {omega} effectively steepens the metal cation concentration gradient at the wire-solution interface, thereby increasing the growth velocity of the wire. For indium wires, increasing {omega} from 0.5 to 3.5 MHz increases their growth velocity from 11 to 78 {mu}m s{sup -1} and reduces their diameter from 770 to 114 nm. Gold wires exhibit diameter-tunability that ranges from 150 nm to 45 nm. Thus, it is possible to tune the wire diameter from the microscale down to the nanoscale. Moreover, this control is a consequence of non-stationary dendritic growth, which distinguishes this process from most previously studied examples of dendritic solidification.

  14. Mechano-transcription of COX-2 is a common response to lumen dilation of the rat gastrointestinal tract

    Science.gov (United States)

    Lin, You-Min; Li, Feng; Shi, Xuan-Zheng

    2014-01-01

    Background In obstructive bowel disorders (OBDs) such as achalasia, pyloric stenosis, and bowel obstruction, the lumen of the affected segments is markedly dilated and the motility function is significantly impaired. We tested the hypothesis that mechanical stress in lumen dilation leads to induction of cyclo-oxygenase-2 (COX-2) in smooth muscle throughout the gastrointestinal (GI) tract, contributing to motility dysfunction. Methods Lumen dilation was induced in vivo with obstruction bands (12 × 3 mm) applied over the lower esophageal sphincter (LES), the pyloric sphincter, and the ileum in rats for 48 hr. Mechanical stretch in vivo was also emulated by balloon distension of the distal colon. Direct stretch of muscle strips from the esophagus, gastric fundus, and ileum was mimicked in an in vitro tissue culture system. Key Results Partial obstruction in the LES, pylorus, and ileum significantly increased expression of COX-2 mRNA and protein in the muscularis externae of the dilated segment oral to the occlusions, but not in the aboral segment. Direct stretch of the lumen in vivo or of muscle strips in vitro markedly induced COX-2 expression. The smooth muscle contractility was significantly suppressed in the balloon distended segments. However, treatment with COX-2 inhibitor NS-398 restored the contractility. Furthermore, in vivo administration of NS-398 in gastric outlet obstruction significantly improved gastric emptying. Conclusions & Inferences Mechanical dilation of the gut lumen by occlusion or direct distension induces gene expression of COX-2 throughout the GI tract. Mechanical stress-induced COX-2 contributes to motility dysfunction in conditions with lumen dilation. PMID:22489918

  15. Learning-based automated segmentation of the carotid artery vessel wall in dual-sequence MRI using subdivision surface fitting.

    Science.gov (United States)

    Gao, Shan; van 't Klooster, Ronald; Kitslaar, Pieter H; Coolen, Bram F; van den Berg, Alexandra M; Smits, Loek P; Shahzad, Rahil; Shamonin, Denis P; de Koning, Patrick J H; Nederveen, Aart J; van der Geest, Rob J

    2017-10-01

    The quantification of vessel wall morphology and plaque burden requires vessel segmentation, which is generally performed by manual delineations. The purpose of our work is to develop and evaluate a new 3D model-based approach for carotid artery wall segmentation from dual-sequence MRI. The proposed method segments the lumen and outer wall surfaces including the bifurcation region by fitting a subdivision surface constructed hierarchical-tree model to the image data. In particular, a hybrid segmentation which combines deformable model fitting with boundary classification was applied to extract the lumen surface. The 3D model ensures the correct shape and topology of the carotid artery, while the boundary classification uses combined image information of 3D TOF-MRA and 3D BB-MRI to promote accurate delineation of the lumen boundaries. The proposed algorithm was validated on 25 subjects (48 arteries) including both healthy volunteers and atherosclerotic patients with 30% to 70% carotid stenosis. For both lumen and outer wall border detection, our result shows good agreement between manually and automatically determined contours, with contour-to-contour distance less than 1 pixel as well as Dice overlap greater than 0.87 at all different carotid artery sections. The presented 3D segmentation technique has demonstrated the capability of providing vessel wall delineation for 3D carotid MRI data with high accuracy and limited user interaction. This brings benefits to large-scale patient studies for assessing the effect of pharmacological treatment of atherosclerosis by reducing image analysis time and bias between human observers. © 2017 American Association of Physicists in Medicine.

  16. [Improvement of sonographic visualization of cannula needle tips by alignment of the needle lumen : In vitro investigation of established needle tip forms].

    Science.gov (United States)

    Schwemmer, U; Geppert, T; Steinfeldt, T; Wunder, C

    2015-10-13

    In the context of ultrasound-guided peripheral nerve blocks (regional anesthesia), clear visualization of the needle tip and the target structure are mandatory for the performance of a safe puncture and injection. The purpose of this in vitro study was to analyze the visualization of different forms of needle tips and calibers of cannulas in a phantom simulating human tissue, with the help of a standardized image analysis system. Different depths and angles of the puncture needle in relation to the ultrasound probe were tested. Cannula needles established for use in regional anesthesia with different surfaces, diameters and needle tip form in 23 different combinations were analyzed. A gelatine-based phantom was used to simulate human tissue. The standardized visualization of the needle tip with the ultrasound probe was performed in plane at different angles (30°, 45° and 60°), depths of penetration (1 cm, 2 cm and 3 cm) and two different alignments of the cannula needle lumen to the ultrasound probe (0° and 180°). The screenshots of the ultrasound pictures were analyzed by quantifying the pixel brightness around the needle tip (region of interest) with a standardized software (score 0-255). In this study 1104 ultrasound images of cannula needles were analyzed. Diminished scores (reduced pixel brightness) of the needle tips were documented with increasing distance from the ultrasound probe. Comparison of punctures at angles of 30° and 45° showed no differences in needle tip visibility (same scores) but punctures at an angle of 60° were poorly visualized compared with 30° and 45° (mean scores 87.90 ± 11.60 vs. 78.40 ± 12.07, p cannula lumen towards the ultrasound probe (0°) was significantly more easily visualized when compared with the reverse alignment of 180° (mean scores 86.90 ± 12.74 vs. 84.80 ± 11.66, p = 0.003, respectively). No differences in visibility were detected between the different cannula needle diameters

  17. Endoscopic visualization of luminal organ and great vessels with three dimensional CT scanner

    International Nuclear Information System (INIS)

    Kobayashi, Hisashi; Okumura, Toshiyuki; Amemiya, Ryuta; Hasegawa, Hiroshi

    1992-01-01

    Thirty cases examined by three dimensional CT scanner (3DCT) are reported. The observation of inner view using 3DCT were performed in 12 large vessels with vascular disorder, 10 pulmonary bronchi with lung cancer and 8 common bile ducts involved obstructive disease. In order to visualize interface of the lumen, a new software, which was developed by HITACHI MEDICO Inc., was used. In all cases but one the inner view of the luminal organ was clearly demonstrated as 3D images and it was possible to judge some changes of luminal interface involved by the diseases. The 3DCT endoscopic image might be useful as a new endoscopic technique without fiberscopy. (author)

  18. Effect of collagen and elastin content on the burst pressure of human blood vessel seals formed with a bipolar tissue sealing system.

    Science.gov (United States)

    Latimer, Cassandra A; Nelson, Meghan; Moore, Camille M; Martin, Kimberly E

    2014-01-01

    Bipolar devices are routinely used to seal blood vessels instead of sutures and clips. Recent work examining the impact of vascular proteins on bipolar seal performance found that collagen and elastin (CE) content within porcine arteries was a significant predictor of a vessel's burst pressure (VBPr). This study examined seal performance across a range of human blood vessels to investigate whether a similar relationship existed. In addition, we compared VBPr and CE content between porcine and human blood vessels. Our primary hypothesis is that higher collagen-to-elastin ratio will predict higher VBPr in human vasculature. In six cadavers, 185 blood vessels from nine anatomic locations were sealed using a bipolar electrosurgical system. A linear mixed model framework was used to evaluate the impact of vessel diameter and CE content on VBPr. The effect of CE ratio on VBPr is modified by vessel size, with CE ratio having larger influence on VBPr in smaller diameter vessels. Seal burst pressure of vessels 2-5 mm in diameter was significantly associated with their CE content. Comparison of average VBPr between species revealed porcine carotid and iliac arteries (440-670 mmHg) to be the best vessel types for predicting the seal strength of most human blood vessels (420-570 mmHg) examined. CE content significantly modified the seal strength of small to medium sized blood vessels but had limited impact on vessels >5 mm. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Green Arctic Patrol Vessel

    Science.gov (United States)

    2011-08-01

    Complement Flexible space for hovercraft , airboats, USVs and RHIBs Naval Surface Warfare Center Carderock Division Green Arctic Patrol Vessel 1...through Sea State 3 (SS3). Flexible capability for a variety of organic craft, such as boat, hovercraft and/or Unmanned Underwater Vehicles (UUVs...2.0, Finland 6.0 2.7 2.8 6 1.8 Hovercraft Griffon/500TD 8.04 3.92 2.41 99 5 ~1.5 Hovercraft Griffon/2000TD 12.7 6.1 3.93 450 20

  20. Refueling system with small diameter rotatable plugs

    International Nuclear Information System (INIS)

    Ritz, W.C.

    1987-01-01

    This patent describes a liquid-metal fastbreeder nuclear reactor comprising a reactor pressure vessel and closure head therefor, a reactor core barrel disposed within the reactor vessel and enclosing a reactor core having therein a large number of closely spaced fuel assemblies, and the reactor core barrel and the reactor core having an approximately concentric circular cross-sectional configuration with a geometric center in predetermined location within the reactor vessel. The improved refueling system described here comprises: a large controllably rotatable plug means comprising the substantial portion of the closure head, a reactor upper internals structure mounted from the large rotatable plug means. The large rotatable plug means has an approximately circular configuration which approximates the cross-sectional configuration of the reactor core barrel with a center of rotation positioned a first predetermined distance from the geometric center of the reactor core barrel so that the large rotatable plug means rotates eccentrically with respect to the reactor core barrel; a small controllably rotatable plug means affixed to the large rotatable plug means and rotatable with respect thereto. The small rotatable plug means has a center of rotation which is offset a second predetermined distance from the rotational center of the large rotatable plug means so that the small rotatable plug means rotates eccentrically with respect to the large rotatable plug means

  1. Modelling of pressure increase protection system for the vacuum vessel of W7-X device

    Energy Technology Data Exchange (ETDEWEB)

    Kaliatka, Tadas, E-mail: tadas.kaliatka@lei.lt; Uspuras, Eugenijus; Kaliatka, Algirdas

    2016-11-01

    Highlights: • Two in-vessel LOCAs (partial and guillotine break of 40 mm diameter pipe of cooling system) for Wendelstein 7-X fusion device were analyzed. • The analysis of the processes in the cooling system, vacuum vessel and pressure increase protection system were performed using thermal-hydraulic RELAP5 Mod3.3 code. • The suitability of pressure increase protection system was assessed. - Abstract: In fusion devices, plasma is contained in a vacuum vessel. The vacuum vessel cannot withstand a pressure above atmospheric. Any damage of in-vessel components could lead to water ingress and may lead to pressure increase and possible damage of vacuum vessel. In order to avoid such undesirable consequences, the pressure increase protection system is designed. In this article, the processes occurring in the vacuum vessel and pressure increase protection system of W7-X device during LOCA (small and guillotine pipe break) event are analyzed. The model of W7-X cooling system, vacuum vessel and pressure increase protection system was developed using RELAP5 code. Numerical analysis of partial and guillotine break of 40 mm diameter pipe of cooling system was performed. Calculation results showed that burst disc of the pressure increase protection system does not open when the cross section area of partial break in the cooling system is smaller than 1 mm{sup 2}. During the guillotine break of cooling system, the burst disc opens, but pressure increase protection system is capable to prevent overpressure of the vacuum vessel.

  2. Impact of final kissing balloon inflation on vessel healing following drug-eluting stent implantation: Insight from the optical coherence tomography sub-study of the J-REVERSE trial.

    Science.gov (United States)

    Takahashi, Hachidai; Otake, Hiromasa; Shinke, Toshiro; Murasato, Yoshinobu; Kinoshita, Yoshihisa; Yamawaki, Masahiro; Takeda, Yoshihiro; Fujii, Kenichi; Yamada, Shin-Ichiro; Shimada, Yoshihisa; Yamashita, Takehiro; Yumoto, Kazuhiko; Hirata, Ken-Ichi

    2016-12-01

    We sought to clarify the impact of final kissing inflation (FKI) after single stenting of bifurcation lesions on vessel healing. From the J-REVERSE registry enrolling 303 bifurcation lesions treated with provisional single stenting using sirolimus- (SES) or everolimus-eluting stent (EES), 65 lesions treated with (n=30) and without (n=35) FKI underwent 9-month follow-up optical coherence tomography. Average stent eccentricity index (SEI: minimum/maximum stent diameter) and neointimal unevenness score (NUS: maximum/average neointimal thickness of the same cross-section) for the proximal, bifurcation, and distal segments were compared between FKI and non-FKI groups. At the proximal segment, the FKI group demonstrated significantly larger average stent area with greater asymmetric stent expansion, and average lumen area remained significantly larger at 9-month follow-up despite a tendency toward greater neointimal proliferation. Jailed strut and thrombus incidence were also significantly lower at the side branch orifice, and NUS was significantly smaller at the bifurcation and proximal segments in the FKI group. Nine months after SES and EES treatment of bifurcation lesions, FKI reduced proximal-segment luminal narrowing. Considering its homogeneous neointimal distribution and fewer jailed struts, FKI may be beneficial for treating bifurcation lesions. Copyright © 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  3. Height - Diameter predictive equations for Rubber (Hevea ...

    African Journals Online (AJOL)

    BUKOLA

    The importance of calibrating models on height-diameter relationship can never be over emphasized in predicting mean ... parameters that variously important in forest growth modeling and many sustainable forest management options(e.g., Van ..... Natural forest Ecosystem, southwest Nigeria. Research Journal of Forestry ...

  4. Liquid-vapor rectilinear diameter revisited

    Science.gov (United States)

    Garrabos, Y.; Lecoutre, C.; Marre, S.; Beysens, D.; Hahn, I.

    2018-02-01

    In the modern theory of critical phenomena, the liquid-vapor density diameter in simple fluids is generally expected to deviate from a rectilinear law approaching the critical point. However, by performing precise scannerlike optical measurements of the position of the SF6 liquid-vapor meniscus, in an approach much closer to criticality in temperature and density than earlier measurements, no deviation from a rectilinear diameter can be detected. The observed meniscus position from far (10 K ) to extremely close (1 mK ) to the critical temperature is analyzed using recent theoretical models to predict the complete scaling consequences of a fluid asymmetry. The temperature dependence of the meniscus position appears consistent with the law of rectilinear diameter. The apparent absence of the critical hook in SF6 therefore seemingly rules out the need for the pressure scaling field contribution in the complete scaling theoretical framework in this SF6 analysis. More generally, this work suggests a way to clarify the experimental ambiguities in the simple fluids for the near-critical singularities in the density diameter.

  5. Maximum Diameter of Impacting Liquid Droplets

    NARCIS (Netherlands)

    Laan, N.; de Bruin, K.G.; Bartolo, D.; Josserand, C.; Bonn, D.

    2014-01-01

    The maximum diameter a droplet that impacts on a surface will attain is the subject of controversy, notably for high-velocity impacts of low-viscosity liquids such as water or blood. We study the impact of droplets of simple liquids of different viscosities, and a shear-thinning complex fluid

  6. Diameter preserving linear maps and isometries, II

    Indian Academy of Sciences (India)

    We study linear bijections of simplex spaces A ( S ) which preserve the diameter of the range, that is, the seminorm ϱ ( f ) = sup { | f ( x ) − f ( y ) | : x , y ∈ S } . Author Affiliations. Félix Cabello Sánchez1. Departamento de Matemáticas, Universidad de Extremadura, Avenida de Elvas 06071- Badajoz, Spain. Dates. Manuscript ...

  7. Vacuum vessels for the LHC magnets arrive at CERN

    CERN Multimedia

    2001-01-01

    The first batch of pre-series vacuum vessels for the LHC dipole magnets has just been delivered to CERN. The vessels are components of the cryostats and will provide the thermal insulation for the superconducting magnets. The first batch of vacuum vessels for the LHC dipole magnets with the team taking part at CERN in ordering and installing them. Left to right : Claude Hauviller, Monique Dupont, Lloyd Williams, Franck Gavin, Alain Jacob, Christophe Vuitton, Davide Bozzini, Laure Sandri, Mikael Sjoholm and André de Saever. In 2006 all that will be seen of the LHC superconducting dipoles in the LHC tunnel will be a line of over 1230 blue cylindrical vacuum vessels. Ten vessels, each weighing 4 tonnes, are already at CERN. On 6 July the first batch of pre-series vessels reached the Lab-oratory from the firm SIMIC Spa whose works are near Savona in north-western Italy. Despite appearances, these 15-metre long, 1-metre diameter blue tubes are much more sophisticated than sections of a run-of-the-mill...

  8. An automated vessel segmentation of retinal images using multiscale vesselness

    International Nuclear Information System (INIS)

    Ben Abdallah, M.; Malek, J.; Tourki, R.; Krissian, K.

    2011-01-01

    The ocular fundus image can provide information on pathological changes caused by local ocular diseases and early signs of certain systemic diseases, such as diabetes and hypertension. Automated analysis and interpretation of fundus images has become a necessary and important diagnostic procedure in ophthalmology. The extraction of blood vessels from retinal images is an important and challenging task in medical analysis and diagnosis. In this paper, we introduce an implementation of the anisotropic diffusion which allows reducing the noise and better preserving small structures like vessels in 2D images. A vessel detection filter, based on a multi-scale vesselness function, is then applied to enhance vascular structures.

  9. Discrimination of intravascular lumen and dissections in single intravascular ultrasound images using subtraction, conventional averaging and saline flush

    NARCIS (Netherlands)

    G. Pasterkamp (Gerard); M.S. van der Heiden (M.); M.J. Post (Mark); C. Borst (Cornelius); E.J. Gussenhoven (Elma); H. Pieterman; H. van Urk (Hero); N. Bom (Klaas)

    1995-01-01

    textabstractWith current 30-MHz intravascular ultrasound systems, flowing blood may cause considerable backscatter which in real-time images is characterized by dynamic speckle. However, in a single intravascular ultrasound image (still-frame) the discrimination between arterial lumen and wall may

  10. Is quantitative coronary angiography reliable in assessing the lumen gain after treatment with the everolimus-eluting bioresorbable polylactide scaffold?

    NARCIS (Netherlands)

    Sotomi, Yohei; Onuma, Yoshinobu; Suwannasom, Pannipa; Tateishi, Hiroki; Tenekecioglu, Erhan; Zeng, Yaping; Cavalcante, Rafael; Jonker, Hans; Dijkstra, Jouke; Foin, Nicolas; Koon, Jaryl Ng Chen; Collet, Carlos; de Winter, Robbert J.; Wykrzykowska, Joanna J.; Stone, Gregg W.; Popma, Jeffrey J.; Kozuma, Ken; Tanabe, Kengo; Serruys, Patrick W.; Kimura, Takeshi

    2016-01-01

    The current study aimed to assess the difference in lumen dimension measurements between optical coherence tomography (OCT) and quantitative coronary angiography (QCA) in the polymeric bioresorbable scaffold and metallic stent. In the randomised ABSORB Japan trial, 87 lesions in the Absorb arm and

  11. Vessel Wall Reaction after Vena Cava Filter Placement

    International Nuclear Information System (INIS)

    Hoekstra, Arend; Elstrodt, Jan M.; Nikkels, Peter G.J.; Tiebosch, Anton T.M.G.

    2002-01-01

    Purpose: To evaluate the interaction between the Cordis Keeper vena caval filter and vessel wall in aporcine model.Methods: Implantation of the filter was performed in five pigs. Radiologic data concerning inferior vena cava(IVC) diameter and filter patency, filter leg span, and stability were collected. At 2 or 6 months post-implantation, histopathologic analysis of the IVC wall was performed.Results: All filters remained patent with no evidence of migration. However, at 6 months follow-up, two legs of one filter penetrated the vessel wall and were adherent to the liver. These preliminary results suggest that with the observed gradual increase in the filter span, the risk of caval wall penetration increases with time, especially in a relatively small IVC(average diameter 16 mm).Conclusion: The Cordis Keeper filter was well tolerated, but seems to be prone to caval wall penetration in the long term

  12. Diameter of the lymphoid follicles in the vermiform appendix of Bangladeshi cadaver.

    Science.gov (United States)

    Rahman, M A; Parash, T H; Banu, L A

    2014-04-01

    Appendicitis is the most common clinical condition of the appendix. Many cases of acute appendicitis result from obstruction of the lumen of the appendix by lymphoid hyperplasia. The vermiform appendix is a worm-like, closed-ended, narrow, small tubular structure, projecting from posteromedial wall of cecum. It is an integral part of the Gut Associated Lymphoid Tissue (GALT) system. The lymphoid follicles of the vermiform appendix vary in respect to their number, diameter and location in different ages. This study was done to measure and establish the normal diameter with age related variation of the lymphoid follicles of vermiform appendix in Bangladeshi population. This descriptive cross sectional study was carried out in the Department of Anatomy, Sir Salimullah Medical College, Dhaka, from January 2008 to June 2009. Sixty (60) postmortem vermiform appendices of different age groups of Bangladeshi cadavers. For studying the diameter of lymphoid follicles in the vermiform appendix in relation to age, the collected samples were divided into five groups namely Group-A between age ranges 0-20 years, Group-B between age ranges 21-30 years, Group-C between age ranges 31-40 years, Group-D 41-50 years and Group-E age above 50 years. From each age group, six (6) fresh samples were selected for histological study. From each vermiform appendix three slides were prepared each from its base, middle part and near the tip and were stained with routine H & E stain. The normal diameter of the follicles of the vermiform appendix ranged from 0.40 mm to 0.66 mm. The highest average group diameter was 0.62±1.10mm in Group-A and the lowest value was 0.45±2.73mm in Group-E. It was obvious that the diameter decreased gradually with advancing age. The average normal diameter of the lymphoid follicles per histological section of vermiform appendix reduced with advancing age and showed a significant negative correlation with age (pvermiform appendix reduced significantly with advancing

  13. Phosphorylation of CEACAM1 molecule by calmodulin kinase IID in a three-dimensional model of mammary gland lumen formation.

    Science.gov (United States)

    Nguyen, Tung; Chen, Charng-Jui; Shively, John E

    2014-01-31

    Carcinoembryonic antigen-related cell adhesion molecule-1 (CEACAM1), a transmembrane protein, expressed on normal breast epithelial cells is down-regulated in breast cancer. Phosphorylation of Thr-457 on the short cytoplasmic domain isoform (CEACAM1-SF) that is predominant in normal epithelial cells is required for lumen formation in a three-dimensional model that involves apoptosis of the central acinar cells. Calmodulin kinase IID (CaMKIID) was selected as a candidate for the kinase required for Thr-457 phosphorylation from a gene chip analysis comparing genes up-regulated in MCF7 cells expressing wild type CEACAM1-SF compared with the T457A-mutated gene (Chen, C. J., Kirshner, J., Sherman, M. A., Hu, W., Nguyen, T., and Shively, J. E. (2007) J. Biol. Chem. 282, 5749-5760). Up-regulation of CaMKIID during lumen formation was confirmed by analysis of mRNA and protein levels. CaMKIID was able to phosphorylate a synthetic peptide corresponding to the cytoplasmic domain of CEACAM1-SF and was covalently bound to biotinylated and T457C-modified peptide in the presence of a kinase trap previously described by Shokat and co-workers (Maly, D. J., Allen, J. A., and Shokat, K. M. (2004) J. Am. Chem. Soc. 126, 9160-9161). When cell lysates from wild type-transfected MCF7 cells undergoing lumen formation were incubated with the peptide and kinase trap, a cross-linked band corresponding to CaMKIID was observed. When these cells were treated with an RNAi that inhibits CaMKIID expression, lumen formation was blocked by over 90%. We conclude that CaMKIID specifically phosphorylates Thr-457 on CEACAM1-SF, which in turn regulates the process of lumen formation via apoptosis of the central acinar cells.

  14. The vessel fluence; Fluence cuve

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This book presents the proceedings of the technical meeting on the reactors vessels fluence. They are grouped in eight sessions: the industrial context and the stakes of the vessels control; the organization and the methodology for the fluence computation; the concerned physical properties; the reference computation methods; the fluence monitoring in an industrial context; vessels monitoring under irradiation; others methods in the world; the research and development programs. (A.L.B.)

  15. Vessel segmentation in screening mammograms

    Science.gov (United States)

    Mordang, J. J.; Karssemeijer, N.

    2015-03-01

    Blood vessels are a major cause of false positives in computer aided detection systems for the detection of breast cancer. Therefore, the purpose of this study is to construct a framework for the segmentation of blood vessels in screening mammograms. The proposed framework is based on supervised learning using a cascade classifier. This cascade classifier consists of several stages where in each stage a GentleBoost classifier is trained on Haar-like features. A total of 30 cases were included in this study. In each image, vessel pixels were annotated by selecting pixels on the centerline of the vessel, control samples were taken by annotating a region without any visible vascular structures. This resulted in a total of 31,000 pixels marked as vascular and over 4 million control pixels. After training, the classifier assigns a vesselness likelihood to the pixels. The proposed framework was compared to three other vessel enhancing methods, i) a vesselness filter, ii) a gaussian derivative filter, and iii) a tubeness filter. The methods were compared in terms of area under the receiver operating characteristics curves, the Az values. The Az value of the cascade approach is 0:85. This is superior to the vesselness, Gaussian, and tubeness methods, with Az values of 0:77, 0:81, and 0:78, respectively. From these results, it can be concluded that our proposed framework is a promising method for the detection of vessels in screening mammograms.

  16. Americium behaviour in plastic vessels

    Energy Technology Data Exchange (ETDEWEB)

    Legarda, F.; Herranz, M. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R., E-mail: raquel.idoeta@ehu.e [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Abelairas, A. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain)

    2010-07-15

    The adsorption of {sup 241}Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of {sup 241}Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of {sup 241}Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.

  17. Americium behaviour in plastic vessels

    International Nuclear Information System (INIS)

    Legarda, F.; Herranz, M.; Idoeta, R.; Abelairas, A.

    2010-01-01

    The adsorption of 241 Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of 241 Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of 241 Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.

  18. War injuries of the blood vessels of the extremities

    Directory of Open Access Journals (Sweden)

    Radulović Svetozar

    2002-01-01

    Full Text Available Treatment results of 200 injured with the lesions of 282 magisterial blood vessels were analyzed. All were combat injuries, and the majority was caused by the fragments of explosive device. The mechanism of such the injuries produced large defects of soft tissues as well as the high level of the wound contamination, which aggravated reconstructive procedures and increased the risk of infection. In the majority of cases anatomic reconstruction of the artery was performed, and the ligature was used only in the case of graft infection and in the injuries of one artery of the lower leg or the forearm. The majority of injuries was solved by lateral suture or patch plastic, since postoperative constriction caused by those methods did not cause greater hemodynamic disorders due to the size of venous lumen. The duration of ischemic interval was of the utmost importance for the favorable final result of the treatment, as well as the adequate debridement of the wound, good soft-tissue cover of the reconstructed blood vessel and precise a traumatic technique. Total percentage of amputations was 14.5%, and all were involving the lower extremities, and were mostly caused by popliteal artery lesion.

  19. Noninvasive diagnosis of thrombus in the heart and large vessels

    International Nuclear Information System (INIS)

    Masuda, Yoshiaki; Morooka, Nobuhiro; Yoshida, Hideo; Watanabe, Shigeru; Inagaki, Yoshiaki

    1984-01-01

    The usefulness of two dimensional echocardiography (2-D echocardiography) and x-ray computed tomography (CT) for the diagnosis of thrombi in the cardiac cavity and large vessels was studied by comparing them with the findings of invasive methods. Among 56 subjects with mitral stenosis, left atrial thrombi were noted in 12 cases (16 regions) by CT and 8 cases (9 regions) by 2-D echocardiography. In 16 subjects who underwent operations, one false negative case by CT and 3 false negative and one false positive cases by 2-D echocardiography were found. In 80 subjects with myocardial infarction 2-D echocardiography, CT and left ventriculography (LVG) were performed at approximately the same time. Thrombi were detected in 10 subjects (12.5%) by 2-D echocardiography, in 15 (18.8%) by CT and in 14 (17.5%) by LVG. Although mural thrombi in abdominal aortic aneurysm were detected very easily, thin thrombi surrounding the false lumen of the dissecting aneurysm were not detected ultrasonographically. These thrombi were only detected by the enhanced CT. Our results show the usefulness of both methods for detecting thrombi in the heart and large vessels. CT can distinguish the thrombi more clearly than 2-D echocardiography, but 2-D echocardiography is performed more easily, safely and economically than CT. (author)

  20. Multiple Coronary Chamber Microfistulas or Persistent Thebesian Vessels?

    Directory of Open Access Journals (Sweden)

    Cernica Daniel

    2017-09-01

    Full Text Available Coronary fistulas are rare, not gender-specific congenital conditions, consisting of communications between the coronary arteries and either another coronary vessel or a cardiac chamber. In contrast to large fistulas, small fistulas, named “minimae cordis veneae” or the Thebesius venous system, are draining into heart chambers and form a vascular network in the cardiac lumen. In this article, we present the case of a 72-year-old female with a significant history of cardiovascular disease, admitted to our clinic because of rest dyspnea, fatigue, and minimal chest pain. The 12-lead electrocardiogram showed a trifascicular block (a second-degree atrioventricular block Mobitz II, associated with a right bundle branch block and left anterior fascicle block and negative T waves in DII, DIII, aVF, V4–V6 leads. An invasive coronary angiography was performed, which revealed no significant atherosclerotic lesions. However, a persistent capillary blush was present at the apex site of the left ventricular chamber, draining from the distal segments of both the anterior descending coronary artery and the posterior interventricular coronary artery. The intramural vascular network generating a left ventricle angiogram image of this kind was suggestive for persistent Thebesian vessels connecting the two coronaries with the left ventricular chamber.

  1. Coke from small-diameter tubes analyzed

    International Nuclear Information System (INIS)

    Albright, L.F.

    1988-01-01

    The mechanism for coke deposit formation and the nature of the coke itself can vary with the design of the ethylene furnace tube bank. In this article, coke deposits from furnaces with small-diameter pyrolysis tubes are examined. The samples were taken from four furnaces of identical design (Plant B). As in both the first and second installments of the series, the coke deposits were examined using a scanning electron microscope (SEM) and an energy dispersive X-ray analyzer (EDAX). The deposits from the small-diameter tubes are compared with the coke deposits from the furnace discussed in earlier articles. Analysis of the coke in both sets of samples are then used to offer recommendations for improved decoking procedures, operating procedures, better feed selection, and better selection of the metallurgy used in furnace tubes, to extend the operating time of the furnace tubes by reducing the amount and type of coke build up

  2. On finding minimum-diameter clique trees

    Energy Technology Data Exchange (ETDEWEB)

    Blair, J.R.S. (Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science); Peyton, B.W. (Oak Ridge National Lab., TN (United States))

    1991-08-01

    It is well-known that any chordal graph can be represented as a clique tree (acyclic hypergraph, join tree). Since some chordal graphs have many distinct clique tree representations, it is interesting to consider which one is most desirable under various circumstances. A clique tree of minimum diameter (or height) is sometimes a natural candidate when choosing clique trees to be processed in a parallel computing environment. This paper introduces a linear time algorithm for computing a minimum-diameter clique tree. The new algorithm is an analogue of the natural greedy algorithm for rooting an ordinary tree in order to minimize its height. It has potential application in the development of parallel algorithms for both knowledge-based systems and the solution of sparse linear systems of equations. 31 refs., 7 figs.

  3. Ultrasound assessment of the posterior circumflex humeral artery in elite volleyball players: Aneurysm prevalence, anatomy, branching pattern and vessel characteristics

    OpenAIRE

    van de Pol, Daan; Maas, Mario; Terpstra, Aart; Pannekoek-Hekman, Marja; Alaeikhanehshir, Sena; Kuijer, P. Paul F. M.; Planken, R. Nils

    2016-01-01

    Objectives To determine the prevalence of posterior circumflex humeral artery (PCHA) aneurysms and vessel characteristics of the PCHA and deep brachial artery (DBA) in elite volleyball players. Methods Two-hundred and eighty players underwent standardized ultrasound assessment of the dominant arm by a vascular technologist. Assessment included determination of PCHA aneurysms (defined as segmental vessel dilatation ?150 %), PCHA and DBA anatomy, branching pattern, vessel course and diameter. R...

  4. [Large vessel vasculitides].

    Science.gov (United States)

    Morović-Vergles, Jadranka; Puksić, Silva; Gracanin, Ana Gudelj

    2013-01-01

    Large vessel vasculitis includes Giant cell arteritis and Takayasu arteritis. Giant cell arteritis is the most common form of vasculitis affect patients aged 50 years or over. The diagnosis should be considered in older patients who present with new onset of headache, visual disturbance, polymyalgia rheumatica and/or fever unknown cause. Glucocorticoides remain the cornerstone of therapy. Takayasu arteritis is a chronic panarteritis of the aorta ant its major branches presenting commonly in young ages. Although all large arteries can be affected, the aorta, subclavian and carotid arteries are most commonly involved. The most common symptoms included upper extremity claudication, hypertension, pain over the carotid arteries (carotidynia), dizziness and visual disturbances. Early diagnosis and treatment has improved the outcome in patients with TA.

  5. Reactor pressure vessel embrittlement

    International Nuclear Information System (INIS)

    1992-07-01

    Within the framework of the IAEA extrabudgetary programme on the Safety of WWER-440/230 NPPs, a list of safety issues requiring broad studies of generic interest have been agreed upon by an Advisory Group who met in Vienna in September 1990. The list was later revised in the light of the programme findings. The information on the status of the issues, and on the amount of work already completed and under way in the various countries, needs to be compiled. Moreover, an evaluation of what further work is required to resolve each one of the issues is also necessary. In view of this, the IAEA has started the preparation of a series of status reports on the various issues. This report on the generic safety issue ''Reactor Pressure Vessel Embrittlement'' presents a comprehensive survey of technical information available in the field and identifies those aspects which require further investigation. 39 refs, 21 figs, 4 tabs

  6. Coronary single vessel disease

    International Nuclear Information System (INIS)

    Kaltenbach, M.; Kober, G.; Satter, P.; Gruentzig, A.; Myler, R.; Sterzer, S.

    1980-01-01

    The seven-years-survival rate is about 80 percent with respect to the most favourable long-time prognosis for coronary single vessel diseases under conservative therapy. In this contribution the control angiography of 76 patients after aorto-coronary bypass operation or transluminal angioplastic is reported. Only two patients subjected to a bypass operation. The recidivity rate is 10 percent after an operation, whereby it is not possible to make a recidivity prognosis. If a recidivity shows up it is being developped during the first three months. If the control angiography three months after the operation shows a good result, then a favourable steady state result can be expected. A comparison of the result with four different centers is given. (APR) [de

  7. A 2D driven 3D vessel segmentation algorithm for 3D digital subtraction angiography data

    Energy Technology Data Exchange (ETDEWEB)

    Spiegel, M; Hornegger, J [Pattern Recognition Lab, University Erlangen-Nuremberg, Erlangen (Germany); Redel, T [Siemens AG Healthcare Sector, Forchheim (Germany); Struffert, T; Doerfler, A, E-mail: martin.spiegel@informatik.uni-erlangen.de [Department of Neuroradiology, University Erlangen-Nuremberg, Erlangen (Germany)

    2011-10-07

    Cerebrovascular disease is among the leading causes of death in western industrial nations. 3D rotational angiography delivers indispensable information on vessel morphology and pathology. Physicians make use of this to analyze vessel geometry in detail, i.e. vessel diameters, location and size of aneurysms, to come up with a clinical decision. 3D segmentation is a crucial step in this pipeline. Although a lot of different methods are available nowadays, all of them lack a method to validate the results for the individual patient. Therefore, we propose a novel 2D digital subtraction angiography (DSA)-driven 3D vessel segmentation and validation framework. 2D DSA projections are clinically considered as gold standard when it comes to measurements of vessel diameter or the neck size of aneurysms. An ellipsoid vessel model is applied to deliver the initial 3D segmentation. To assess the accuracy of the 3D vessel segmentation, its forward projections are iteratively overlaid with the corresponding 2D DSA projections. Local vessel discrepancies are modeled by a global 2D/3D optimization function to adjust the 3D vessel segmentation toward the 2D vessel contours. Our framework has been evaluated on phantom data as well as on ten patient datasets. Three 2D DSA projections from varying viewing angles have been used for each dataset. The novel 2D driven 3D vessel segmentation approach shows superior results against state-of-the-art segmentations like region growing, i.e. an improvement of 7.2% points in precision and 5.8% points for the Dice coefficient. This method opens up future clinical applications requiring the greatest vessel accuracy, e.g. computational fluid dynamic modeling.

  8. A 2D driven 3D vessel segmentation algorithm for 3D digital subtraction angiography data

    International Nuclear Information System (INIS)

    Spiegel, M; Hornegger, J; Redel, T; Struffert, T; Doerfler, A

    2011-01-01

    Cerebrovascular disease is among the leading causes of death in western industrial nations. 3D rotational angiography delivers indispensable information on vessel morphology and pathology. Physicians make use of this to analyze vessel geometry in detail, i.e. vessel diameters, location and size of aneurysms, to come up with a clinical decision. 3D segmentation is a crucial step in this pipeline. Although a lot of different methods are available nowadays, all of them lack a method to validate the results for the individual patient. Therefore, we propose a novel 2D digital subtraction angiography (DSA)-driven 3D vessel segmentation and validation framework. 2D DSA projections are clinically considered as gold standard when it comes to measurements of vessel diameter or the neck size of aneurysms. An ellipsoid vessel model is applied to deliver the initial 3D segmentation. To assess the accuracy of the 3D vessel segmentation, its forward projections are iteratively overlaid with the corresponding 2D DSA projections. Local vessel discrepancies are modeled by a global 2D/3D optimization function to adjust the 3D vessel segmentation toward the 2D vessel contours. Our framework has been evaluated on phantom data as well as on ten patient datasets. Three 2D DSA projections from varying viewing angles have been used for each dataset. The novel 2D driven 3D vessel segmentation approach shows superior results against state-of-the-art segmentations like region growing, i.e. an improvement of 7.2% points in precision and 5.8% points for the Dice coefficient. This method opens up future clinical applications requiring the greatest vessel accuracy, e.g. computational fluid dynamic modeling.

  9. Dark-lumen magnetic resonance colonography in patients with suspected sigmoid diverticulitis: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Ajaj, Waleed; Lauenstein, Thomas; Goehde, Susanne; Kuehle, Christiane; Herborn, Christoph U. [University Hospital, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Ruehm, Stefan G. [University of California, Department of Radiology, David Geffen School of Medicine, Los Angeles, CA (United States); Langhorst, Jost; Zoepf, Thomas; Gerken, Guido [University Hospital, Department of Gastroenterology and Hepatology, Essen (Germany); Goyen, Mathias [Medical Center Hamburg-Eppendorf, Hamburg (Germany)

    2005-11-01

    To assess dark-lumen magnetic resonance colonography (MRC) for the evaluation of patients with suspected sigmoid diverticulitis. Forty patients with suspected sigmoid diverticulitis underwent MRC within 72 h prior to conventional colonoscopy (CC). A three-dimensional T1-weighted volumetric interpolated breath-hold examination sequence was acquired after an aqueous enema and intravenous administration of gadolinium-based contrast agents. All MRC data were evaluated by two radiologists. Based on wall thickness and focal uptake of contrast material and pericolic reaction including mesenteric infiltration on T1-weighted sequence the sigmoid colon was assessed for the presence of diverticulitis. MRC classified 17 of the 40 patients as normal with regard to sigmoid diverticulitis. However, CC confirmed the presence of light inflammatory signs in four patients which were missed in MRC. MRC correctly identified wall thickness and contrast uptake of the sigmoid colon in the other 23 patients. In three of these patients false-positive findings were observed, and MRC classified the inflammation of the sigmoid colon as diverticulitis whereas CC and histopathology confirmed invasive carcinoma. MRC detected additionally relevant pathologies of the entire colon and could be performed in cases where CC was incomplete. MRC may be considered a promising alternative to CC for the detection of sigmoid diverticulitis. (orig.)

  10. Rap1 integrates tissue polarity, lumen formation, and tumorigenicpotential in human breast epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Masahiko; Nelson, Celeste M.; Myers, Connie A.; Bissell,Mina J.

    2006-09-29

    Maintenance of apico-basal polarity in normal breast epithelial acini requires a balance between cell proliferation, cell death, and proper cell-cell and cell-extracellular matrix signaling. Aberrations in any of these processes can disrupt tissue architecture and initiate tumor formation. Here we show that the small GTPase Rap1 is a crucial element in organizing acinar structure and inducing lumen formation. Rap1 activity in malignant HMT-3522 T4-2 cells is appreciably higher than in S1 cells, their non-malignant counterparts. Expression of dominant-negative Rap1 resulted in phenotypic reversion of T4-2 cells, led to formation of acinar structures with correct apico-basal polarity, and dramatically reduced tumor incidence despite the persistence of genomic abnormalities. The resulting acini contained prominent central lumina not observed when other reverting agents were used. Conversely, expression of dominant-active Rap1 in T4-2 cells inhibited phenotypic reversion and led to increased invasiveness and tumorigenicity. Thus, Rap1 acts as a central regulator of breast architecture, with normal levels of activation instructing apical polarity during acinar morphogenesis, and increased activation inducing tumor formation and progression to malignancy.

  11. "Detachment of the carinal hook following endobronchial intubation with a double lumen tube"

    Directory of Open Access Journals (Sweden)

    Rocha Ana C

    2011-10-01

    Full Text Available Abstract Background Carinal hooks increases difficulty at endotracheal intubation. Amputation of the carinal hook during passage and malpositioning of the tube to the hook are some of the potential problems related with left-sided Carlens double lumen tube (DLT. This article reports an amputation of the hook during a difficult selective intubation and aimed at calling the attention to complications associated with DLTs and the importance of fiberoptic bronchoscopy. Case presentation A 68 year-old woman was scheduled for right-sided thoracotomy in whom blind DLT insertion was performed. Narrowed trachea causes difficulty in rotating the DLT 90° counter-clockwise. After carinal hook was noticed upon visual inspection of the DLT, fiberoptic bronchoscopy was used to remove the missing part (with the use of forceps from the right mainstem bronchus. Conclusion Insertion of DLTs with carinal hook is associated with technical problems and potentially life-threatening hazards have discouraged their use. Fiberoptic evaluation and repositioning solves most of the problems. Although amputation of the carinal hook has not been previously reported, clinicians should be alert. This case report emphasizes the utility of the fiberoptic bronchoscopy in the operating theatre for placement, positioning and inspection of the carinal hook DLT.

  12. Dark-lumen magnetic resonance colonography in patients with suspected sigmoid diverticulitis: a feasibility study

    International Nuclear Information System (INIS)

    Ajaj, Waleed; Lauenstein, Thomas; Goehde, Susanne; Kuehle, Christiane; Herborn, Christoph U.; Ruehm, Stefan G.; Langhorst, Jost; Zoepf, Thomas; Gerken, Guido; Goyen, Mathias

    2005-01-01

    To assess dark-lumen magnetic resonance colonography (MRC) for the evaluation of patients with suspected sigmoid diverticulitis. Forty patients with suspected sigmoid diverticulitis underwent MRC within 72 h prior to conventional colonoscopy (CC). A three-dimensional T1-weighted volumetric interpolated breath-hold examination sequence was acquired after an aqueous enema and intravenous administration of gadolinium-based contrast agents. All MRC data were evaluated by two radiologists. Based on wall thickness and focal uptake of contrast material and pericolic reaction including mesenteric infiltration on T1-weighted sequence the sigmoid colon was assessed for the presence of diverticulitis. MRC classified 17 of the 40 patients as normal with regard to sigmoid diverticulitis. However, CC confirmed the presence of light inflammatory signs in four patients which were missed in MRC. MRC correctly identified wall thickness and contrast uptake of the sigmoid colon in the other 23 patients. In three of these patients false-positive findings were observed, and MRC classified the inflammation of the sigmoid colon as diverticulitis whereas CC and histopathology confirmed invasive carcinoma. MRC detected additionally relevant pathologies of the entire colon and could be performed in cases where CC was incomplete. MRC may be considered a promising alternative to CC for the detection of sigmoid diverticulitis. (orig.)

  13. Using digital photo technology to improve visualization of gastric lumen CT images

    International Nuclear Information System (INIS)

    Pyrgioti, M.; Kyriakidis, A.; Chrysostomou, S.; Panaritis, V.

    2006-01-01

    In order to evaluate the gastric lumen CT images better, a new method is being applied to images using an Image Processing software. During a 12-month period, 69 patients with various gastric symptoms and 20 normal (as far as it concerns the upper gastrointestinal system) volunteers underwent computed tomography of the upper gastrointestinal system. Just before the examination the patients and the normal volunteers underwent preparation with 40 ml soda water and 10 ml gastrografin. All the CT images were digitized with an Olympus 3.2 Mpixel digital camera and further processed with an Image Processing software. The administration per os of gastrografin and soda water resulted in the distension of the stomach and consequently better visualization of all the anatomic parts. By using an Image Processing software in a PC, all the pathological and normal images of the stomach were better diagnostically estimated. We believe that the photo digital technology improves the diagnostic capacity not only of the CT image but also in MRI and probably many other imaging methods

  14. Improving lumen maintenance by nanopore array dispersed quantum dots for on-chip light emitting diodes

    Science.gov (United States)

    Chen, Quan; Yang, Fan; Wan, Renzhuo; Fang, Dong

    2017-12-01

    The temperature stability of quantum dots (QDs), which is crucial for integrating into high power light-emitting diodes (LEDs) in the on-chip configuration, needs to be further improved. In this letter, we report warm white LEDs, where CdSe/ZnS nanoparticles were incorporated into a porous anodic alumina (PAA) matrix with a chain structure by the self-assembly method. Experiments demonstrate that the QD concentration range in toluene solvent from 1% mg/μl to 1.2% mg/μl in combination with the PAA matrix shows the best luminous property. To verify the reliability of the as-prepared device, a comparison experiment was conducted. It indicates excellent lumen maintenance of the light source and less chromaticity coordinate shift under accelerated life testing conditions. Experiments also prove that optical depreciation was only up to 4.6% of its initial value after the 1500 h aging test at the junction temperature of 76 °C.

  15. Microembolism after Endovascular Treatment of Unruptured Cerebral Aneurysms: Reduction of its Incidence by Microcatheter Lumen Aspiration.

    Science.gov (United States)

    Kim, Dae Yoon; Park, Jung Cheol; Kim, Jae Kyun; Sung, Yu Sub; Park, Eun Suk; Kwak, Jae Hyuk; Choi, Choong-Gon; Lee, Deok Hee

    2015-09-01

    Diffusion-weighted MR images (DWI) obtained after endovascular treatment of cerebral aneurysms frequently show multiple high-signal intensity (HSI) dots. The purpose of this study was to see whether we could reduce their incidence after embolization of unruptured cerebral aneurysms by modification of our coiling technique, which involves the deliberate aspiration of the microcatheter lumen right after delivery of each detachable coil into the aneurysm sac. From January 2011 to June 2011, all 71 patients with unruptured cerebral aneurysms were treated using various endovascular methods. During the earlier period, 37 patients were treated using our conventional embolization technique (conventional period). Then 34 patients were treated with a modified coiling technique (modified period). DWI was obtained on the following day. We compared the occurrence of any DWI HSI lesions and the presence of the symptomatic lesions during the two time periods. The incidence of the DWI HSI lesions differed significantly at 89.2% (33/37) during the conventional period and 26.5% (9/34) during the modified period (p < 0.0001). The incidence of symptomatic lesions differed between the two periods (29.7% during the conventional period vs. 2.9% during the modified period, p < 0.003). Aspiration of the inner content of the microcatheter right after detachable coil delivery was helpful for the reduction of the incidence of microembolisms after endovascular coil embolization for the treatment of unruptured cerebral aneurysms.

  16. Numerical Investigation of Characteristic of Anisotropic Thermal Conductivity of Natural Fiber Bundle with Numbered Lumens

    Directory of Open Access Journals (Sweden)

    Guan-Yu Zheng

    2014-01-01

    Full Text Available Natural fiber bundle like hemp fiber bundle usually includes many small lumens embedded in solid region; thus, it can present lower thermal conduction than that of conventional fibers. In the paper, characteristic of anisotropic transverse thermal conductivity of unidirectional natural hemp fiber bundle was numerically studied to determine the dependence of overall thermal property of the fiber bundle on that of the solid region phase. In order to efficiently predict its thermal property, the fiber bundle was embedded into an imaginary matrix to form a unit composite cell consisting of the matrix and the fiber bundle. Equally, another unit composite cell including an equivalent solid fiber was established to present the homogenization of the fiber bundle. Next, finite element thermal analysis implemented by ABAQUS was conducted in the two established composite cells by applying proper thermal boundary conditions along the boundary of unit cell, and influences of the solid region phase and the equivalent solid fiber on the composites were investigated, respectively. Subsequently, an optional relationship of thermal conductivities of the natural fiber bundle and the solid region was obtained by curve fitting technique. Finally, numerical results from the obtained fitted curves were compared with the analytic Hasselman-Johnson’s results and others to verify the present numerical model.

  17. Hollowing or cavitation during follicular lumen formation in the differentiating thyroid of grass snake Natrix natrix L. (Lepidosauria, Serpentes) embryos? An ultrastructural study.

    Science.gov (United States)

    Rupik, Weronika

    2012-12-01

    The mechanism of follicular lumen differentiation during thyroid gland morphogenesis in vertebrate classes is still unclear and the current knowledge regarding the origin and the mechanism of follicular lumen formation during thyroid differentiation in reptiles is especially poor. The present study reports on an ultrastructural investigation of thyroid follicle formation and follicular lumen differentiation in grass snake (Natrix natrix L.) embryos. The results of this study show that the earliest morphogenesis of the presumptive thyroid follicles in grass snake embryos appears to be similar to that described in embryos of other vertebrate classes; however, differences appeared during the later stages of its differentiation when the follicular lumen was formed. The follicular lumen in grass snake embryos was differentiated by cavitation; during thyroid follicle formation, a population of centrally located cells was cleared through apoptosis to form the lumen. This manner of follicular lumen differentiation indicates that it has an extracellular origin. It cannot be excluded that other types of programmed cell death also occur during follicular lumen formation in this snake species. Copyright © 2012 Elsevier GmbH. All rights reserved.

  18. “Aroused and sustained by the Holy Spirit”? A Plea for a Pneumatological Reconsideration of Sensus Fidei on the Basis of Lumen Gentium 12

    NARCIS (Netherlands)

    Moons, Jos

    2018-01-01

    The author wishes to contribute to the reflection on sensus fidei by highlighting an aspect of Lumen gentium’s teaching on this topic that is often dealt with superficially, or not at all, namely its pneumatology. Revisiting Lumen gentium, no. 12, he firstly demonstrates that the drafting process is

  19. Intravital two-photon microscopy of immune cell dynamics in corneal lymphatic vessels.

    Directory of Open Access Journals (Sweden)

    Philipp Steven

    Full Text Available BACKGROUND: The role of lymphatic vessels in tissue and organ transplantation as well as in tumor growth and metastasis has drawn great attention in recent years. METHODOLOGY/PRINCIPAL FINDINGS: We now developed a novel method using non-invasive two-photon microscopy to simultaneously visualize and track specifically stained lymphatic vessels and autofluorescent adjacent tissues such as collagen fibrils, blood vessels and immune cells in the mouse model of corneal neovascularization in vivo. The mouse cornea serves as an ideal tissue for this technique due to its easy accessibility and its inducible and modifiable state of pathological hem- and lymphvascularization. Neovascularization was induced by suture placement in corneas of Balb/C mice. Two weeks after treatment, lymphatic vessels were stained intravital by intrastromal injection of a fluorescently labeled LYVE-1 antibody and the corneas were evaluated in vivo by two-photon microscopy (TPM. Intravital TPM was performed at 710 nm and 826 nm excitation wavelengths to detect immunofluorescence and tissue autofluorescence using a custom made animal holder. Corneas were then harvested, fixed and analyzed by histology. Time lapse imaging demonstrated the first in vivo evidence of immune cell migration into lymphatic vessels and luminal transport of individual cells. Cells immigrated within 1-5.5 min into the vessel lumen. Mean velocities of intrastromal corneal immune cells were around 9 µm/min and therefore comparable to those of T-cells and macrophages in other mucosal surfaces. CONCLUSIONS: To our knowledge we here demonstrate for the first time the intravital real-time transmigration of immune cells into lymphatic vessels. Overall this study demonstrates the valuable use of intravital autofluorescence two-photon microscopy in the model of suture-induced corneal vascularizations to study interactions of immune and subsequently tumor cells with lymphatic vessels under close as possible

  20. Auxin and ethylene regulation of diameter growth in trees.

    Science.gov (United States)

    Savidge, R A

    1988-12-01

    Recent studies on the phytohormonal regulation of seasonal cell-division activity in the cambium, primary-wall radial expansion of cambial derivatives, differentiation of xylem cells, and growth of the cortex in forest trees of the north temperate zone are reviewed. Indol-3-ylacetic acid (IAA, auxin) has been characterized by combined gas chromatography-mass spectrometry (GC-MS) in the cambial region of Abies balsamea, Pinus densiflora, Pinus sylvestris and Quercus robur. All of the evidence supports the hypothesis that developing leaves and extending shoots are primary sources of IAA. The rate of ethylene emanation varies among conifer species when adjoining phloem and cambial tissues are incubated in vitro. The cambium from young cuttings of Abies balsamea produces more ethylene than that from older cuttings. Ethylene production by seven-year-old Abies balsamea cambium is substantially increased in vitro when the tissue is provided with exogenous 1-aminocyclopropane-1-carboxylic acid and IAA. In response to elevated ethylene concentrations, cortex growth is accelerated in both hardwood and conifer seedlings. Ethrel (2-chloroethylphosphonic acid) increases ray size and ray-cell number and promotes traumatic resin-canal development in xylem. In Ulmus americana, endogenous ethylene concentrations are inversely correlated with cambial activity. Ethylene decreases vessel diameter in Acer negundo, Acer platanoides and Ulmus americana. Several studies suggest that ethylene has a role in regulating reaction-wood formation in both conifers and hardwoods.

  1. Ultrastructure of a Mobile Threadlike Tissue Floating in a Lymph Vessel

    Directory of Open Access Journals (Sweden)

    Sharon Jiyoon Jung

    2016-01-01

    Full Text Available Observations of the primo vascular system (PVS floating in lymph ducts were reported by various groups. There have been, however, no studies on the ultrastructure of the entire cross section of a primo vessel (PV inside a lymph vessel with a transmission electron microscope (TEM. In the current study we took the TEM images of a cross section of the PV inside a lymph vessel. We used the Alcian blue staining method for the finding of the target PV in a lymphatic vessel by injecting the dye into the inguinal lymph nodes. The stained PV was harvested together with the lymph vessel and some parts of the specimens were used for studying with optical microscopes. Some other parts were treated according to a standard protocol for TEM. As the results the TEM study revealed the loosely distributed collagen fibers with plenty of empty spaces and the lumens with the endothelial nuclei. It turned out to be very similar to the ultrastructure of the PVs observed on the surfaces of internal organs. It also showed how compactly the PV is surrounded with lymphocytes. In conclusion, the detailed morphological features like the distribution of fibers in the PV were revealed and shown to be similar to another kind of the PV on the surfaces of internal organs.

  2. Pressure vessel for nuclear reactors

    International Nuclear Information System (INIS)

    1975-01-01

    The invention applies to a pressure vessel for nuclear reactors whose shell, made of cast metal segments, has a steel liner. This liner must be constructed to withstand all operational stresses and to be easily repairable. The invention solves this problem by installing the liner at a certain distance from the inner wall of the pressure vessel shell and by filling this clearance with supporting concrete. Both the concrete and the steel liner must have a lower prestress than the pressure vessel shell. In order to avoid damage to the liner when prestressing the pressure vessel shell, special connecting elements are provided which consist of welded-on fastening elements projecting into recesses in the cast metal segments of the pressure vessel. Their design is described in detail. (TK) [de

  3. Fast and robust shape diameter function.

    Science.gov (United States)

    Chen, Shuangmin; Liu, Taijun; Shu, Zhenyu; Xin, Shiqing; He, Ying; Tu, Changhe

    2018-01-01

    The shape diameter function (SDF) is a scalar function defined on a closed manifold surface, measuring the neighborhood diameter of the object at each point. Due to its pose oblivious property, SDF is widely used in shape analysis, segmentation and retrieval. However, computing SDF is computationally expensive since one has to place an inverted cone at each point and then average the penetration distances for a number of rays inside the cone. Furthermore, the shape diameters are highly sensitive to local geometric features as well as the normal vectors, hence diminishing their applications to real-world meshes which often contain rich geometric details and/or various types of defects, such as noise and gaps. In order to increase the robustness of SDF and promote it to a wide range of 3D models, we define SDF by offsetting the input object a little bit. This seemingly minor change brings three significant benefits: First, it allows us to compute SDF in a robust manner since the offset surface is able to give reliable normal vectors. Second, it runs many times faster since at each point we only need to compute the penetration distance along a single direction, rather than tens of directions. Third, our method does not require watertight surfaces as the input-it supports both point clouds and meshes with noise and gaps. Extensive experimental results show that the offset-surface based SDF is robust to noise and insensitive to geometric details, and it also runs about 10 times faster than the existing method. We also exhibit its usefulness using two typical applications including shape retrieval and shape segmentation, and observe a significant improvement over the existing SDF.

  4. Conduit vessel blood flow during the trek to Mount Everest base camp.

    Science.gov (United States)

    Dumais, Valerie; Nault, Patrice; Tsertsvadze, Alexander; Forbes, Thomas L

    2011-12-01

    Hemodynamic changes in response to the hypoxic environment of high altitude are vascular bed-specific. The aim of the present study was to investigate diameter and blood flow changes in conduit vessels in response to hypobaric hypoxia. Eleven healthy subjects ascending Mount Everest to base camp participated in this study. Vessel diameter and blood velocity for brachial, carotid, common femoral, superficial femoral, and deep femoral arteries were measured by portable Doppler ultrasound. Blood flow was calculated from these values. Measurements were taken at sea level, at increasing altitudes on ascent to base camp (1310 m, 3470 m, 5330 m), and repeated on descent to lower altitude (1310 m). For all vessels except carotids, both vessel diameter and blood flow decreased between sea level and initial ascent to altitude, with subsequent persistence of these decreased values; there was no further significant change with continued ascent to higher altitude. Blood flow for all arteries (except carotids) increased significantly on descent to lower altitude, with an associated nonsignificant increase in velocity and decrease in diameter. This study showed that there is vasoconstriction of limb conduit vessels at altitude, which persists upon descent to lower altitude. Blood flow in these vessels also decreases with initial exposure to high altitude, yet increases when returning to lower altitude, reflecting variations in blood velocity. Carotid arteries responded differently to the stimulus of hypobaria than limb conduit vessels; there was no change in diameter seen on ascent or descent, but there was a progressive decrease in blood flow on ascent, with no change on subsequent descent. Copyright © 2011 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

  5. 29 mm Diameter Target Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olivas, Eric Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Naranjo, Angela Carol [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-10-23

    After numerous delays, the test of the 29 mm diameter target was conducted on 8/18/2017. The complete target design report, dated 8/15/2016, is reproduced below for completeness. This describes in detail the 10 disk target with varying thickness disks. The report presents and discusses the test results. In brief summary, there appears to have been multiple instrumentation errors. Measured temperatures, pressures and IR camera window temperature measurement are all suspect. All tests were done at 35 MeV, with 171 μA current, or 6 kW of beam power.

  6. A Posteriori-Derived Dietary Patterns and Retinal Vessel Caliber in an Elderly Population

    OpenAIRE

    McEvoy, CT; Cardwell, CR; Chakravarthy, U; Hogg, RE; McKinley, MC; Young, IS; Fletcher, AE; Woodside, JV

    2013-01-01

    PURPOSE. To examine the association between a posteriori-derived dietary patterns (DP) and retinal vessel caliber in an elderly population. METHODS. This was a cross-sectional study of 288 elderly adults (>65 years) who participated in the European Eye study (EUREYE) Northern Irish cohort. DP were extracted using principal component analysis from completed food frequency questionnaires. Semi-automated computer grading was used to determine the mean retinal vessel diameters (central retinal ar...

  7. Photoaffinity labeling of the lumenal K+ site of the gastric (H+ + K+)-ATPase

    International Nuclear Information System (INIS)

    Keeling, D.J.; Fallowfield, C.; Lawrie, K.M.; Saunders, D.; Richardson, S.; Ife, R.J.

    1989-01-01

    A photoaffinity label for the lumenal K+ site of the gastric (H+ + K+)-ATPase has been identified. Seven azido derivatives based upon the reversible K+ site inhibitor SCH 28080 were studied, one of which, m-ATIP (8-(3-azidophenylmethoxy)-1,2,3-trimethylimidazo[1,2-a] pyridinium iodide), was subsequently synthesized in radiolabeled form. In the absence of UV irradiation, m-ATIP inhibited K+ -stimulated ATPase activity in lyophilized gastric vesicles competitively with respect to K+, with a Ki value of 2.4 microM at pH 7.0. Irradiation of lyophilized gastric vesicles at pH 7.0 with [ 14 C]m-ATIP in the presence of 0.2 mM ATP resulted in a time-dependent inactivation of ATPase activity that was associated with an incorporation of radioactivity into a 100-kDa polypeptide representing the catalytic subunit of the (H+ + K+)-ATPase. Both inactivation and incorporation were blocked in the presence of 10 mM KCl but not with 10 mM NaCl, consistent with interaction at the K+ site. The level of incorporation required to produce complete inhibition of ATPase activity was 1.9 +/- 0.2 times the number of catalytic phosphorylation sites in the same preparation. Tryptic digestion of gastric vesicle membranes, labeled with [ 14 C]m-ATIP, failed to release the radioactivity from the membranes suggesting that the site of interaction was close to or within the membrane-spanning sections of this ion pump

  8. McGrath Series 5 videolaryngoscope vs Airtraq DL videolaryngoscope for double-lumen tube intubation

    Science.gov (United States)

    Wan, Li; Liao, Mingfeng; Li, Li; Qian, Wei; Hu, Rong; Chen, Kun; Zhang, Chuanhan; Yao, Wenlong

    2016-01-01

    Abstract Background: Many studies have shown Airtraq videolaryngoscope provided faster tracheal intubation and a higher success rate than other videolaryngoscopes. Recently, different types of videolaryngoscopes have been reported for use in double-lumen tube (DLT) intubation. However, the advantages and disadvantages between them remain undetermined for DLT intubation. In this study, we compared the Airtraq DL videolaryngoscope with the McGrath Series 5 videolaryngoscope for DLT intubation by experienced anesthesiologists. Methods: Ninety patients with expected normal airways were randomly allocated to either the Airtraq or McGrath group. The primary outcome was DLT intubation time. The secondary outcomes were glottic view, success rate, subjective ease of intubation (100-mm visual analog scale, 0 = easy; 100 = difficult), incidence of DLT malposition, and postoperative intubation-related complication. Results: The airway characteristics were comparable between the 2 groups. Cormack and Lehane grades significantly improved with the use of the McGrath and Airtraq videolaryngoscopes, compared with the Macintosh laryngoscope. The intubation success rate on the first attempt was 93% in the Airtraq group and 95% in the McGrath group (P > 0.05). The intubation time in the McGrath group is longer than that in the Airtraq group (39.9 [9.1]s vs 28.6 [13.6]s, P  0.05). Conclusions: When using videolaryngoscopes for DLT intubation, the Airtraq DL is superior to the McGrath Series 5 in intubation time, but it does not decrease intubation difficulty. PMID:28002347

  9. Polymeric immunoglobulin receptor in intestinal immune defense against the lumen-dwelling protozoan parasite Giardia.

    Science.gov (United States)

    Davids, Barbara J; Palm, J E Daniel; Housley, Michael P; Smith, Jennifer R; Andersen, Yolanda S; Martin, Martin G; Hendrickson, Barbara A; Johansen, Finn-Eirik; Svärd, Staffan G; Gillin, Frances D; Eckmann, Lars

    2006-11-01

    The polymeric Ig receptor (pIgR) is conserved in mammals and has an avian homologue, suggesting evolutionarily important functions in vertebrates. It transports multimeric IgA and IgM across polarized epithelia and is highly expressed in the intestine, yet little direct evidence exists for its importance in defense against common enteric pathogens. In this study, we demonstrate that pIgR can play a critical role in intestinal defense against the lumen-dwelling protozoan parasite Giardia, a leading cause of diarrheal disease. The receptor was essential for the eradication of Giardia when high luminal IgA levels were required. Clearance of Giardia muris, in which IgA plays a dominant role, was severely compromised in pIgR-deficient mice despite significant fecal IgA output at 10% of normal levels. In contrast, eradication of the human strain Giardia lamblia GS/M, for which adaptive immunity is less IgA dependent in mice, was unaffected by pIgR deficiency, indicating that pIgR had no physiologic role when lower luminal IgA levels were sufficient for parasite elimination. Immune IgA was greatly increased in the serum of pIgR-deficient mice, conferred passive protection against Giardia, and recognized several conserved giardial Ags, including ornithine carbamoyltransferase, arginine deiminase, alpha-enolase, and alpha- and beta-giardins, that are also detected in human giardiasis. Corroborative observations were made in mice lacking the J chain, which is required for pIgR-dependent transepithelial IgA transport. These results, together with prior data on pIgR-mediated immune neutralization of luminal cholera toxin, suggest that pIgR is essential in intestinal defense against pathogenic microbes with high-level and persistent luminal presence.

  10. SU-F-T-20: Novel Catheter Lumen Recognition Algorithm for Rapid Digitization

    Energy Technology Data Exchange (ETDEWEB)

    Dise, J; McDonald, D; Ashenafi, M; Peng, J; Mart, C; Koch, N; Vanek, K [Medical University of South Carolina, Charleston, SC (United States)

    2016-06-15

    Purpose: Manual catheter recognition remains a time-consuming aspect of high-dose-rate brachytherapy (HDR) treatment planning. In this work, a novel catheter lumen recognition algorithm was created for accurate and rapid digitization. Methods: MatLab v8.5 was used to create the catheter recognition algorithm. Initially, the algorithm searches the patient CT dataset using an intensity based k-means filter designed to locate catheters. Once the catheters have been located, seed points are manually selected to initialize digitization of each catheter. From each seed point, the algorithm searches locally in order to automatically digitize the remaining catheter. This digitization is accomplished by finding pixels with similar image curvature and divergence parameters compared to the seed pixel. Newly digitized pixels are treated as new seed positions, and hessian image analysis is used to direct the algorithm toward neighboring catheter pixels, and to make the algorithm insensitive to adjacent catheters that are unresolvable on CT, air pockets, and high Z artifacts. The algorithm was tested using 11 HDR treatment plans, including the Syed template, tandem and ovoid applicator, and multi-catheter lung brachytherapy. Digitization error was calculated by comparing manually determined catheter positions to those determined by the algorithm. Results: he digitization error was 0.23 mm ± 0.14 mm axially and 0.62 mm ± 0.13 mm longitudinally at the tip. The time of digitization, following initial seed placement was less than 1 second per catheter. The maximum total time required to digitize all tested applicators was 4 minutes (Syed template with 15 needles). Conclusion: This algorithm successfully digitizes HDR catheters for a variety of applicators with or without CT markers. The minimal axial error demonstrates the accuracy of the algorithm, and its insensitivity to image artifacts and challenging catheter positioning. Future work to automatically place initial seed

  11. Containment vessel stability analysis

    International Nuclear Information System (INIS)

    Harstead, G.A.; Morris, N.F.; Unsal, A.I.

    1983-01-01

    The stability analysis for a steel containment shell is presented herein. The containment is a freestanding shell consisting of a vertical cylinder with a hemispherical dome. It is stiffened by large ring stiffeners and relatively small longitudinal stiffeners. The containment vessel is subjected to both static and dynamic loads which can cause buckling. These loads must be combined prior to their use in a stability analysis. The buckling loads were computed with the aid of the ASME Code case N-284 used in conjunction with general purpose computer codes and in-house programs. The equations contained in the Code case were used to compute the knockdown factors due to shell imperfections. After these knockdown factors were applied to the critical stress states determined by freezing the maximum dynamic stresses and combining them with other static stresses, a linear bifurcation analysis was carried out with the aid of the BOSOR4 program. Since the containment shell contained large penetrations, the Code case had to be supplemented by a local buckling analysis of the shell area surrounding the largest penetration. This analysis was carried out with the aid of the NASTRAN program. Although the factor of safety against buckling obtained in this analysis was satisfactory, it is claimed that the use of the Code case knockdown factors are unduly conservative when applied to the analysis of buckling around penetrations. (orig.)

  12. Structural analysis of the JT-60SA cryostat vessel body

    Energy Technology Data Exchange (ETDEWEB)

    Botija, José, E-mail: jose.botija@ciemat.es [Association EURATOM – CIEMAT, Avda. Complutense 40, 28040 Madrid (Spain); Alonso, Javier; Fernández, Pilar; Medrano, Mercedes; Ramos, Francisco; Rincon, Esther; Soleto, Alfonso [Association EURATOM – CIEMAT, Avda. Complutense 40, 28040 Madrid (Spain); Davis, Sam; Di Pietro, Enrico; Tomarchio, Valerio [Fusion for Energy, JT-60SA European Home Team, 85748 Garching bei Munchen (Germany); Masaki, Kei; Sakasai, Akira; Shibama, Yusuke [JAEA – Japan Atomic Energy Agency, Naka Fusion Institute, Ibaraki 311-0193 (Japan)

    2013-10-15

    Highlights: ► Structural analysis to validate the JT-60SA cryostat vessel body design. ► Design code ASME 2007 “Boiler and Pressure Vessel Code. Section VIII”. ► First buckling mode: load multiplier of 10.644, higher than the minimum factor 4.7. ► Elastic and elastic–plastic stress analysis meets ASME against plastic collapse. ► Bolted fasteners have been analyzed showing small gaps closed by strong welding. -- Abstract: The JT-60SA cryostat is a stainless steel vacuum vessel (14 m diameter, 16 m height) which encloses the Tokamak providing the vacuum environment (10{sup −3} Pa) necessary to limit the transmission of thermal loads to the components at cryogenic temperature. It must withstand both external atmospheric pressure during normal operation and internal overpressure in case of an accident. The paper summarizes the structural analyses performed in order to validate the JT-60SA cryostat vessel body design. It comprises several analyses: a buckling analysis to demonstrate stability under the external pressure; an elastic and an elastic–plastic stress analysis according to ASME VIII rules, to evaluate resistance to plastic collapse including localized stress concentrations; and, finally, a detailed analysis with bolted fasteners in order to evaluate the behavior of the flanges, assuring the integrity of the vacuum sealing welds of the cryostat vessel body.

  13. Cold source vessel development for the advanced neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Williams, P.T.; Lucas, A.T. [Oak Ridge National Lab., TN (United States)

    1995-09-01

    The Advanced Neutron Source (ANS), in its conceptual design phase at Oak Ridge National Laboratory (ORNL), will be a user-oriented neutron research facility that will produce the most intense flux of neutrons in the world. Among its many scientific applications, the productions of cold neutrons is a significant research mission for the ANS. The cold neutrons come from two independent cold sources positioned near the reactor core. Contained by an aluminum alloy vessel, each cold source is a 410 mm diameter sphere of liquid deuterium that functions both as a neutron moderator and a cryogenic coolant. With nuclear heating of the containment vessel and internal baffling, steady-state operation requires close control of the liquid deuterium flow near the vessel`s inner surface. Preliminary thermal-hydraulic analyses supporting the cold source design are being performed with multi-dimensional computational fluid dynamics simulations of the liquid deuterium flow and heat transfer. This paper presents the starting phase of a challenging program and describes the cold source conceptual design, the thermal-hydraulic feasibility studies of the containment vessel, and the future computational and experimental studies that will be used to verify the final design.

  14. The outback catheter: a new device for true lumen re-entry after dissection during recanalization of arterial occlusions.

    Science.gov (United States)

    Hausegger, Klaus A; Georgieva, Borjana; Portugaller, Horst; Tauss, Josef; Stark, Gerhard

    2004-01-01

    To report the initial experience with a new catheter system (The Outback catheter) designed to allow fluoroscopically controlled re-entry of the true arterial lumen after subintimal guidewire passage during recanalization procedures of arterial occlusions. The catheter was used in 10 patients with intermittent claudication caused by chronic segmental occlusions of the superficial femoral or popliteal arteries. In all patients, conventional guidewire recanalization had failed. In 8 patients, successful true lumen re-entry was achieved with the Outback catheter. Percutaneous transluminal angioplasty was successfully performed in these patients without complications. Two technical failures occurred in heavily calcified arteries. The Outback catheter was safe and effective when used in complicated recanalization procedures in the superficial femoral and popliteal artery and the tibial trunk.

  15. Activity of LUMEN (1996-97) Understanding of PbWO4 Scintillator Characteristics and their Optimisation

    CERN Document Server

    Baccaro, Stefania; Borgia, Bruno; Cecilia, Angelica; Croci, S; Dafinei, Ioan; Diemoz, Marcella; Fabeni, P; Festinesi, Armando; Jarolímek, O; Longo, Egidio; Martini, M; Mihoková, E; Montecchi, Marco; Nikl, M; Nitsch, K; Organtini, Giovanni; Pazzi, G P; Spinolo, G; Vedda, A

    1998-01-01

    The aim of the LUMEN co-operation, supported by INFN, is to obtain ful experimental characterisation and deep expertise of heavy scintillator for high energy physics. The advantage of this collaboration was mainly in the complementary character of the experimental techniques available in the partner laboratories and in the availability of highly experienced scientists indifferent fields. Furthermore close feedback to technological laboratories preparing on request PWO samples appeared extremely helpful. The present paper reports on the most important results obtained during the LUMEN activity in 1996-97. The aim of the report is to provide also enough useful information for the PWO application and novel ideas to stimulate further interest for new detectors as well as application in different fields.

  16. Sagittal Abdominal Diameter: Application in Clinical Practice

    Directory of Open Access Journals (Sweden)

    Thaís Da Silva-Ferreira

    2014-05-01

    Full Text Available Excess visceral fat is associated with cardiovascular risk factors. Sagittal abdominal diameter (SAD has recently been highlighted as an indicator of abdominal obesity, and also may be useful in predicting cardiovascular risk. The purpose of the present study was to review the scientific literature on the use of SAD in adult nutritional assessment. A search was conducted for scientific articles in the following electronic databases: SciELO , MEDLINE (PubMed and Virtual Health Library. SAD is more associated with abdominal fat (especially visceral, and with different cardiovascular risk factors, such as, insulin resistance, blood pressure, and serum lipoproteins than the traditional methods of estimating adiposity, such as body mass index and waist-to-hip ratio. SAD can also be used in association with other anthropometric measures. There are still no cut-off limits established to classify SAD as yet. SAD can be an alternative measure to estimate visceral adiposity. However, the few studies on this diameter, and the lack of consensus on the anatomical site to measure SAD, are obstacles to establish cut-off limits to classify it.

  17. Comprehensive Analysis of Chicken Vessels as Microvascular Anastomosis Training Model

    Directory of Open Access Journals (Sweden)

    Bo Young Kang

    2017-01-01

    Full Text Available BackgroundNonliving chickens are commonly used as a microvascular anastomosis training model. However, previous studies have investigated only a few types of vessel, and no study has compared the characteristics of the various vessels. The present study evaluated the anatomic characteristics of various chicken vessels as a training model.MethodsEight vessels—the brachial artery, basilic vein, radial artery, ulnar artery, ischiatic artery and vein, cranial tibial artery, and common dorsal metatarsal artery—were evaluated in 26 fresh chickens and 30 chicken feet for external diameter (ED and thicknesses of the tunica adventitia and media. The dissection time from skin incision to application of vessel clamps was also measured.ResultsThe EDs of the vessels varied. The ischiatic vein had the largest ED of 2.69±0.33 mm, followed by the basilic vein (1.88±0.36 mm, ischiatic artery (1.68±0.24 mm, common dorsal metatarsal artery (1.23±0.23 mm, cranial tibial artery (1.18±0.19 mm, brachial artery (1.08±0.15 mm, ulnar artery (0.82±0.13 mm, and radial artery (0.56±0.12 mm, and the order of size was consistent across all subjects. Thicknesses of the tunica adventitia and media were also diverse, ranging from 74.09±19.91 µm to 158.66±40.25 µm (adventitia and from 31.2±7.13 µm to 154.15±46.48 µm (media, respectively. Mean dissection time was <3 minutes for all vessels.ConclusionsOur results suggest that nonliving chickens can provide various vessels with different anatomic characteristics, which can allow trainees the choice of an appropriate microvascular anastomosis training model depending on their purpose and skillfulness.

  18. Time course of arterial remodelling in diameter and wall thickness above and below the lesion after a spinal cord injury.

    Science.gov (United States)

    Thijssen, Dick H J; De Groot, Patricia C E; van den Bogerd, Arne; Veltmeijer, Matthijs; Cable, N Timothy; Green, Daniel J; Hopman, Maria T E

    2012-12-01

    Physical inactivity in response to a spinal cord injury (SCI) represents a potent stimulus for conduit artery remodelling. Changes in conduit artery characteristics may be induced by the local effects of denervation (and consequent extreme inactivity below the level of the lesion), and also by systemic adaptations due to whole body inactivity. Therefore, we assessed the time course of carotid (i.e. above lesion) and common femoral artery (i.e. below lesion) lumen diameter and wall thickness across the first 24 weeks after an SCI. Eight male subjects (mean age 35 ± 14 years) with a traumatic motor complete spinal cord lesion between T5 and L1 (i.e. paraplegia) were included. Four subjects were measured across the first 6 weeks after SCI, whilst another four subjects were measured from 8 until 24 weeks after SCI. Ultrasound was used to examine the diameter and wall thickness from the carotid and common femoral arteries. Carotid artery diameter did not change across 24 weeks, whilst femoral artery diameter stabilised after the rapid initial decrease during the first 3 weeks after the SCI. Carotid and femoral artery wall thickness showed no change during the first few weeks, but increased both between 6 and 24 weeks (P < 0.05). In conclusion, SCI leads to a rapid and localised decrease in conduit artery diameter which is isolated to the denervated and paralyzed region, whilst wall thickness gradually increases both above and below the lesion. This distinct time course of change in conduit arterial diameter and wall thickness suggests that distinct mechanisms may contribute to these adaptations.

  19. Engineering design and integration of in-vessel single turn segmental coil in vacuum vessel of SST-1

    Science.gov (United States)

    Jayswal, Snehal; Chauhan, P.; Santra, P.; Vasava, K.; Perekh, T.; Patel, H.; Biswas, P.; Pradhan, S.

    2017-04-01

    SST-1 tokamak is having the error field due to unsymmetrical positioning of Toroidal field coils which push the plasma to inner side from its major radius of 1100 mm. hence it is required to install the In-vessel Coil (PF6) at a location of 1350 mm radius and elevation of 350 mm above and below the mid plane of the toroidal field coils. The In-Vessel coil was decided to make in eight segments for futuristic use, to control the individual localized error field correction by supplying the different current. A single turn, eight segments, copper conductor with 18 mm diameter with GFRP insulation and in housed in SS304 L casing to carry 8000 A current for 10 s was designed and installed in vacuum vessel of SST-1. This paper will present the design drivers, material selection, advantages and constraints of the in-vessel coils, its conceptual and engineering design, CAD models, finite element analysis using ANSYS, its fabrication, quality assurance/control and assembly/integration aspects inside vacuum vessel of SST-1.

  20. Evaluation of the conformity of assistential practice in the maintenance of the temporary double-lumen dialysis catheter.

    Science.gov (United States)

    Rosetti, Késia Alves Gomes; Tronchin, Daisy Maria Rizatto

    2014-01-01

    to evaluate the conformity of the assistential practice in the maintenance of the temporary double-lumen catheter for hemodialysis, by means of the use of the process indicator, in the University Hospital of the University of São Paulo. a quantitative, exploratory-descriptive and observational study. The sample was made up of 155 observations of persons with temporary double-lumen catheters, in the period March-November 2011, using the Indicator of the Maintenance of the Temporary Double Lumen Catheter for Hemodialysis. the rate of general conformity of the assistential practice corresponded to 65.8%. Of the practice's 13 components, 9 (69.2%) attained 100% conformity. The hygienization of hands by the professionals and the use of a mask by the patients during the disconnection from the hemodialysis had the worst rates (83.9%). although the actions evaluated are implemented in the unit, it is necessary to propose and apply educational strategies with the health team, as well as to institute periodical assessments, so as to raise the conformity rates, ensuring the quality of the hemodialysis services.

  1. ERα-mediated repression of pro-inflammatory cytokine expression by glucocorticoids reveals a crucial role for TNFα and IL1α in lumen formation and maintenance

    Science.gov (United States)

    Eritja, Nuria; Mirantes, Cristina; Llobet, David; Masip, Gemma; Matias-Guiu, Xavier; Dolcet, Xavi

    2012-01-01

    Most glandular tissues comprise polarized epithelial cells organized around a single central lumen. Although there is active research investigating the molecular networks involved in the regulation of lumenogenesis, little is known about the extracellular factors that influence lumen formation and maintenance. Using a three-dimensional culture system of epithelial endometrial cells, we have revealed a new role for pro-inflammatory cytokines such as TNFα and IL1α in the formation and, more importantly, maintenance of a single central lumen. We also studied the mechanism by which glucocorticoids repress TNFα and IL1α expression. Interestingly, regulation of pro-inflammatory cytokine expression and subsequent lumen formation is mediated by estrogen receptor α (ERα) but not by the glucocorticoid receptor. Finally, we investigated the signaling pathways involved in the regulation of lumen formation by pro-inflammatory cytokines. Our results demonstrate that activation of the ERK/MAPK signaling pathway, but not the PI3K/Akt signaling pathway, is important for the formation and maintenance of a single central lumen. In summary, our results suggest a novel role for ERα-regulated pro-inflammatory cytokine expression in lumen formation and maintenance. PMID:22328525

  2. Vacuum vessel for thermonuclear device

    International Nuclear Information System (INIS)

    Hagiwara, Koji; Imura, Yasuya.

    1979-01-01

    Purpose: To provide constituted method for easily performing baking of vacuum vessel, using short-circuiting segments. Constitution: At the time of baking, one turn circuit is formed by the vacuum vessel and short-circuiting segments, and current transformer converting the one turn circuit into a secondary circuit by the primary coil and iron core is formed, and the vacuum vessel is Joule heated by an induction current from the primary coil. After completion of baking, the short-circuiting segments are removed. (Kamimura, M.)

  3. PWR vessel inspection performance improvements

    International Nuclear Information System (INIS)

    Blair Fairbrother, D.; Bodson, Francis

    1998-01-01

    A compact robot for ultrasonic inspection of reactor vessels has been developed that reduces setup logistics and schedule time for mandatory code inspections. Rather than installing a large structure to access the entire weld inspection area from its flange attachment, the compact robot examines welds in overlapping patches from a suction cup anchor to the shell wall. The compact robot size allows two robots to be operated in the vessel simultaneously. This significantly reduces the time required to complete the inspection. Experience to date indicates that time for vessel examinations can be reduced to fewer than four days. (author)

  4. The Candy-Plug Technique: Technical Aspects and Early Results of a New Endovascular Method for False Lumen Occlusion in Chronic Aortic Dissection.

    Science.gov (United States)

    Rohlffs, Fiona; Tsilimparis, Nikolaos; Fiorucci, Beatrice; Heidemann, Franziska; Debus, Eike Sebastian; Kölbel, Tilo

    2017-08-01

    To describe the technical aspects and early results of the Candy-Plug technique for endovascular false lumen occlusion in chronic aortic dissection. A retrospective single-center study analyzing 18 consecutive patients (mean age 63 years, range 44-76; 16 men) with thoracic false lumen aneurysm in chronic aortic dissection. All patients underwent thoracic endovascular aortic repair with false lumen occlusion using the Candy-Plug technique. Primary endpoints consisted of technical success (successful deployment) and clinical success (no false lumen backflow). Secondary endpoints included 30-day mortality and morbidity as well as aortic remodeling during follow-up. Technical success was 100%. Additional intraprocedural false lumen embolization at the Candy-Plug level was needed in 1 patient due to persisting false lumen backflow on the final angiogram (clinical success 94%). There were no intraprocedural complications. In the perioperative period, there were 3 minor complications: transient mild spinal cord ischemia, cervical hematoma after carotid-subclavian bypass, and a common femoral artery pseudoaneurysm. No deaths or reinterventions occurred. Complete distal false lumen occlusion was present on postoperative computed tomography in 15 patients, while 3 had minor contrast enhancement in the distal false lumen. Over a mean 9-month follow-up (range 0-26), 1 patient died due to rupture. Follow-up >6 months was available in 10 patients (mean 14.7 months, range 7-26): 7 patients showed aortic remodeling, while aneurysm size was stable in 3 patients. The Candy-Plug technique is a feasible endovascular method to achieve false lumen occlusion and aortic remodeling in chronic aortic dissection. It is associated with low morbidity and mortality due to its minimal invasiveness.

  5. Special enclosure for a pressure vessel

    International Nuclear Information System (INIS)

    Wedellsborg, B.W.; Wedellsborg, U.W.

    1993-01-01

    A pressure vessel enclosure is described comprising a primary pressure vessel, a first pressure vessel containment assembly adapted to enclose said primary pressure vessel and be spaced apart therefrom, a first upper pressure vessel jacket adapted to enclose the upper half of said first pressure vessel containment assembly and be spaced apart therefrom, said upper pressure vessel jacket having an upper rim and a lower rim, each of said rims connected in a slidable relationship to the outer surface of said first pressure vessel containment assembly, mean for connecting in a sealable relationship said upper rim of said first upper pressure vessel jacket to the outer surface of said first pressure vessel containment assembly, means for connecting in a sealable relationship said lower rim of said first upper pressure vessel jacket to the outer surface of said first pressure vessel containment assembly, a first lower pressure vessel jacket adapted to enclose the lower half of said first pressure vessel containment assembly and be spaced apart therefrom, said lower pressure vessel jacket having an upper rim connected in a slidable relationship to the outer surface of said first pressure vessel containment assembly, and means for connecting in a sealable relationship said upper rim of said first lower pressure vessel jacket to the outer surface of said first pressure vessel containment assembly, a second upper pressure vessel jacket adapted to enclose said first upper pressure vessel jacket and be spaced apart therefrom, said second upper pressure vessel jacket having an upper rim and a lower rim, each of said rims adapted to slidably engage the outer surface of said first upper pressure vessel jacket, means for sealing said rims, a second lower pressure vessel jacket adapted to enclose said first lower pressure vessel jacket and be spaced apart therefrom

  6. Passive pressure-diameter relationship and structural composition of rat mesenteric lymphangions.

    Science.gov (United States)

    Rahbar, Elaheh; Weimer, Jon; Gibbs, Holly; Yeh, Alvin T; Bertram, Christopher D; Davis, Michael J; Hill, Michael A; Zawieja, David C; Moore, James E

    2012-12-01

    Lymph flow depends on both the rate of lymph production by tissues and the extent of passive and active pumping. Here we aim to characterize the passive mechanical properties of a lymphangion in both mid-lymphangion and valve segments to assess regional differences along a lymphangion, as well as evaluating its structural composition. Mesenteric lymphatic vessels were isolated and cannulated in a microchamber for pressure-diameter (P-D) testing. Vessels were inflated from 0 to 20 cmH(2)O at a rate of 4 cmH(2)O/min, and vessel diameter was continuously tracked, using an inverted microscope, video camera, and custom LabVIEW program, at both mid-lymphangion and valve segments. Isolated lymphatic vessels were also pressure-fixed at 2 and 7 cmH(2)O and imaged using a nonlinear optical microscope (NLOM) to obtain collagen and elastin structural information. We observed a highly nonlinear P-D response at low pressures (3-5 cmH(2)O), which was modeled using a three-parameter constitutive equation. No significant difference in the passive P-D response was observed between mid-lymphangion and valve regions. NLOM imaging revealed an inner elastin layer and outer collagen layer at all locations. Lymphatic valve leaflets were predominantly elastin with thick axially oriented collagen bands at the insertion points. We observed a highly nonlinear P-D response at low pressures (3-5 cmH(2)O) and developed the first constitutive equation to describe the passive P-D response for a lymphangion. The passive P-D response did not vary among regions, in agreement with the composition of elastin and collagen in the lymphatic wall.

  7. Reactor Pressure Vessel (RPV) Acquisition Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Mizia, Ronald Eugene [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2008-04-01

    The Department of Energy has selected the High Temperature Gas-cooled Reactor design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production. It will have an outlet gas temperature in the range of 900°C and a plant design service life of 60 years. The reactor design will be a graphite moderated, helium-cooled, prismatic or pebble-bed reactor and use low-enriched uranium, TRISO-coated fuel. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Materials Research and Development (R&D) Program is responsible for performing R&D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. Selection of the technology and design configuration for the NGNP must consider both the cost and risk profiles to ensure that the demonstration plant establishes a sound foundation for future commercial deployments. The NGNP challenge is to achieve a significant advancement in nuclear technology while at the same time setting the stage for an economically viable deployment of the new technology in the commercial sector soon after 2020. The purpose of this report is to address the acquisition strategy for the NGNP Reactor Pressure Vessel (RPV). This component will be larger than any nuclear reactor pressure vessel presently in service in the United States. The RPV will be taller, larger in diameter, thicker walled, heavier and most likely fabricated at the Idaho National Laboratory (INL) site of multiple subcomponent pieces. The pressure vessel steel can either be a conventional materials already used in the nuclear industry such as listed within ASME A508/A533 specifications or it will be fabricated from newer pressure vessel materials never before used for a nuclear reactor in the US. Each of these characteristics will present a

  8. Three-dimensional reconstruction of rat dermal blood vessels in vivo

    Science.gov (United States)

    Barton, Jennifer K.; Izatt, Joseph A.; Kulkarni, Manish D.; Welch, Ashley J.

    1997-05-01

    We performed imaging and reconstruction of dermal and subdermal blood vessels in a rat skin flap window model. The window model consists of a double thickness of dorsal skin which is sutured to a holding fixture. A 1 cm circle of skin is removed from one thickness, exposing the dermal blood vessels of the opposing side. An optical coherence tomography system operating at 1310 nm was used to image the blood vessels. A series of transverse images of the window model characterized sections of tissue. Off-the-shelf software for desktop and workstation computers was used to preprocess the images, identify and reconstruct blood vessels, and to extract parameters such depth, diameter, and percent volume of blood vessels. Such parameters may be of interest in developing improved treatments for vascular disorders such as port wine stains.

  9. A system for the thermal insulation of a pre-stressed concrete vessel

    International Nuclear Information System (INIS)

    Aubert, Gilles; Petit, Guy.

    1975-01-01

    This invention concerns the thermal insulation of a pre-stressed concrete vessel for a pressurised water nuclear reactor, this vessel being fitted internally with a leak-proof metal lining. Two rings are placed at the lower and upper parts of the vessel respectively. The upper ring is closed with a cover. These rings differ in diameter, are fitted with a metal insulating and mark the limits of a chamber between the vaporisable fluid and the internal wall of the vessel. This chamber is filled with a fluid in the liquid phase up to the liquid/vapor interface level of the fluid and with a gas above that level, the covering of the rings forming a cold fluid liquid seal. Each ring is supported by the vessel. Leak-proof components take up the radial expansion of the rings [fr

  10. 2013 East Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  11. SC/OQ Vessel Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data tables holding information for the Surf Clam/Ocean Quahog vessel and dealer/processor logbooks (negative and positive), as well as individual tag information...

  12. 2013 West Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  13. 2011 Great Lakes Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  14. Targeting Therapy Resistant Tumor Vessels

    National Research Council Canada - National Science Library

    Ruoslahti, Erkki

    2007-01-01

    .... To achieve this, we have developed tumor models for vascular normalization and are using in vivo phage display and isolation of peptides that specifically home to normalized tumor vessels resistant...

  15. Targeting Therapy Resistant Tumor Vessels

    National Research Council Canada - National Science Library

    Ruoslahti, Erkki

    2008-01-01

    .... To achieve this, we have developed tumor models for vascular normalization and are using in vivo phage display and isolation of peptides that specifically home to normalized tumor vessels resistant...

  16. Vessel Permit System Data Set

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — GARFO issues federal fishing permits annually to owners of fishing vessels who fish in the Greater Atlantic region, as required by federal regulation. These permits...

  17. Level indicator for pressure vessels

    Science.gov (United States)

    Not Available

    1982-04-28

    A liquid-level monitor for tracking the level of a coal slurry in a high-pressure vessel including a toroidal-shaped float with magnetically permeable bands thereon disposed within the vessel, two pairs of magnetic-field generators and detectors disposed outside the vessel adjacent the top and bottom thereof and magnetically coupled to the magnetically permeable bands on the float, and signal-processing circuitry for combining signals from the top and bottom detectors for generating a monotonically increasing analog control signal which is a function of liquid level. The control signal may be utilized to operate high-pressure control valves associated with processes in which the high-pressure vessel is used.

  18. Caribbean PR Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch (landed catch) and effort for fishing trips made by vessels fishing in Puerto Rico. The catch and effort data for the entire trip are...

  19. Reactor pressure vessel status report

    International Nuclear Information System (INIS)

    Strosnider, J.; Wichman, K.; Elliot, B.

    1994-12-01

    This report gives a brief description of the reactor pressure vessel (RPV), followed by a discussion of the radiation embrittlement of RPV beltline materials and the two indicators for measuring embrittlement, the end-of-license (EOL) reference temperature and the EOL upper-shelf energy. It also summarizes the GL 92-01 effort and presents, for all 37 boiling water reactor plants and 74 pressurized water reactor plants in the United States, the current status of compliance with regulatory requirements related to ensuring RPV integrity. The staff has evaluated the material data needed to predict neutron embrittlement of the reactor vessel beltline materials. These data will be stored in a computer database entitled the reactor vessel integrity database (RVID). This database will be updated annually to reflect the changes made by the licensees in future submittals and will be used by the NRC staff to assess the issues related to vessel structural integrity

  20. 2013 Great Lakes Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  1. Coastal Discard Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data on the type and amount of marine resources that are discarded or interacted with by vessels that are selected to report to the Southeast...

  2. 2011 East Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  3. Prosopomorphic vessels from Moesia Superior

    Directory of Open Access Journals (Sweden)

    Nikolić Snežana

    2008-01-01

    Full Text Available The prosopomorphic vessels from Moesia Superior had the form of beakers varying in outline but similar in size. They were wheel-thrown, mould-made or manufactured by using a combination of wheel-throwing and mould-made appliqués. Given that face vessels are considerably scarcer than other kinds of pottery, more than fifty finds from Moesia Superior make an enviable collection. In this and other provinces face vessels have been recovered from military camps, civilian settlements and necropolises, which suggests that they served more than one purpose. It is generally accepted that the faces-masks gave a protective role to the vessels, be it to protect the deceased or the family, their house and possessions. More than forty of all known finds from Moesia Superior come from Viminacium, a half of that number from necropolises. Although tangible evidence is lacking, there must have been several local workshops producing face vessels. The number and technological characteristics of the discovered vessels suggest that one of the workshops is likely to have been at Viminacium, an important pottery-making centre in the second and third centuries.

  4. Computational Fluid Dynamics Analysis of Pulsatile Blood Flow Behavior in Modelled Stenosed Vessels with Different Severities

    Directory of Open Access Journals (Sweden)

    Mohsen Mehrabi

    2012-01-01

    Full Text Available This study focuses on the behavior of blood flow in the stenosed vessels. Blood is modelled as an incompressible non-Newtonian fluid which is based on the power law viscosity model. A numerical technique based on the finite difference method is developed to simulate the blood flow taking into account the transient periodic behaviour of the blood flow in cardiac cycles. Also, pulsatile blood flow in the stenosed vessel is based on the Womersley model, and fluid flow in the lumen region is governed by the continuity equation and the Navier-Stokes equations. In this study, the stenosis shape is cosine by using Tu and Devil model. Comparing the results obtained from three stenosed vessels with 30%, 50%, and 75% area severity, we find that higher percent-area severity of stenosis leads to higher extrapressure jumps and higher blood speeds around the stenosis site. Also, we observe that the size of the stenosis in stenosed vessels does influence the blood flow. A little change on the cross-sectional value makes vast change on the blood flow rate. This simulation helps the people working in the field of physiological fluid dynamics as well as the medical practitioners.

  5. Effects of Voluntary Locomotion and Calcitonin Gene-Related Peptide on the Dynamics of Single Dural Vessels in Awake Mice.

    Science.gov (United States)

    Gao, Yu-Rong; Drew, Patrick J

    2016-02-24

    The dura mater is a vascularized membrane surrounding the brain and is heavily innervated by sensory nerves. Our knowledge of the dural vasculature has been limited to pathological conditions, such as headaches, but little is known about the dural blood flow regulation during behavior. To better understand the dynamics of dural vessels during behavior, we used two-photon laser scanning microscopy (2PLSM) to measure the diameter changes of single dural and pial vessels in the awake mouse during voluntary locomotion. Surprisingly, we found that voluntary locomotion drove the constriction of dural vessels, and the dynamics of these constrictions could be captured with a linear convolution model. Dural vessel constrictions did not mirror the large increases in intracranial pressure (ICP) during locomotion, indicating that dural vessel constriction was not caused passively by compression. To study how behaviorally driven dynamics of dural vessels might be altered in pathological states, we injected the vasodilator calcitonin gene-related peptide (CGRP), which induces headache in humans. CGRP dilated dural, but not pial, vessels and significantly reduced spontaneous locomotion but did not block locomotion-induced constrictions in dural vessels. Sumatriptan, a drug commonly used to treat headaches, blocked the vascular and behavioral the effects of CGRP. These findings suggest that, in the awake animal, the diameters of dural vessels are regulated dynamically during behavior and during drug-induced pathological states. Copyright © 2016 the authors 0270-6474/16/362503-14$15.00/0.

  6. A Clinical Anatomic Study of Internal Mammary Perforators as Recipient Vessels for Breast Reconstruction

    Directory of Open Access Journals (Sweden)

    In-Soo Baek

    2013-11-01

    Full Text Available BackgroundPartially resecting ribs of the recipient site to facilitate easy anastomosis of the internal mammary vessels to free flaps during breast reconstruction can cause chest wall pain or deformities. To avoid this, the intercostal perforating branches of the internal mammary vessels can be used for anastomosis. The purpose of this study was to investigate the location and size of the internal mammary perforator vessels based on clinical intraoperative findings and to determine their reliability as recipient vessels for breast reconstruction with microsurgical free tissue transfer.MethodsTwelve patients were preoperatively screened for the presence of internal mammary perforators using Doppler tracing. After modified radical mastectomy was performed by a general surgeon, the location and size of the internal mammary perforator vessels were microscopically investigated. The external diameter was examined using a vessel-measuring gauge from a mechanical coupling device, and the distance from the mid-sternal line to the perforator was also measured.ResultsThe largest arterial perforator averaged 1.5 mm, and the largest venous perforator averaged 2.2 mm. Perforators emerging from the second intercostal space had the largest average external diameter; the second intercostal space also had the largest number of perforators arising from it. The average distance from the mid-sternal line to the perforator was 20.2 mm.ConclusionsInternal mammary perforators presented consistent and reliable anatomy in this study. Based on these results, the internal mammary perforators appear to have a suitable diameter for microvascular anastomosis and should be considered as an alternative recipient vessel to the internal mammary vessel.

  7. Packing configuration performance for small stem diameters

    International Nuclear Information System (INIS)

    Aikin, J.A.; Spence, C.G.; Cumming, D.

    1997-01-01

    The extensive use of graphite packing and its excellent track record for large isolating valves in CANDU, Primary Heat Transfer (PHT) systems has resulted in an increased application of graphite packing on the conventional side. Many of these applications are in air operated valves (AOVs) where the packing sets are used on small stem diameters (<1 inch) with frequent short-cycling strokes (± 10% of full stroke). The direct application of the proven packing configurations for large isolated valves to control valve application has generated problems such as stiction, packing wear and, in isolated cases, stem stall. To address this issue, a test program was conducted at AECL, CRL by MED branch. The testing showed that by reconfiguring the packing sets and using PTFE wafers reductions in stem friction of 50% at ambient conditions, a 3 fold at hot conditions are achievable. The test program also demonstrated benefits gained in packing wear with different stem roughness finishes and the potential need to exercise small stems valves that see less than full stroke cycling. The paper describes the tests results and provides field support experience. (author)

  8. CALiPER Retail Lamps Study 3.2: Lumen and Chromaticity Maintenance of LED A Lamps Operated in Steady-State Conditions

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-12-31

    This CALiPER report examines lumen depreciation and color shift of 17 different A lamps in steady-state conditions (15 LED, 1 CFL, 1 halogen). The goal of this investigation was to examine the long-term performance of complete LED lamps relative to benchmark halogen and CFL lamps—in this case, A lamps emitting approximately 800 lumens operated continuously at a relatively high ambient temperature of 45°C.

  9. The TPX vacuum vessel and in-vessel components

    International Nuclear Information System (INIS)

    Heitzenroeder, P.; Bialek, J.; Ellis, R.; Kessel, C.; Liew, S.

    1994-01-01

    The Tokamak Physics Experiment (TPX) is a superconducting tokamak with double-null diverters. TPX is designed for 1,000-second discharges with the capability of being upgraded to steady state operation. High neutron yields resulting from the long duration discharges require that special consideration be given to materials and maintainability. A unique feature of the TPX is the use of a low activation, titanium alloy vacuum vessel. Double-wall vessel construction is used since it offers an efficient solution for shielding, bakeout and cooling. Contained within the vacuum vessel are the passive coil system, Plasma Facing Components (PFCs), magnetic diagnostics, and the internal control coils. All PFCs utilize carbon-carbon composites for exposed surfaces

  10. Testing internal coatings in metal vessels

    Science.gov (United States)

    Ruby, A.; Perkins, P.

    1978-01-01

    Presence of pinholes or defects in nonconductive protective coating on inside surface of closed vessel is detected if vessel has one opening into which small stainless-steel probe can be introduced. By inserting probe and attaching another to outside surface, and by filling vessel with ten percent sodium chloride solution, integrity of coating is determined by measuring electrical conductivity through vessel wall.

  11. 46 CFR 119.330 - Pressure vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Pressure vessels. 119.330 Section 119.330 Shipping COAST... Machinery § 119.330 Pressure vessels. All unfired pressure vessels must be installed to the satisfaction of the cognizant OCMI. The design, construction, and original testing of such unfired pressure vessels...

  12. 46 CFR 182.330 - Pressure vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Pressure vessels. 182.330 Section 182.330 Shipping COAST...) MACHINERY INSTALLATION Auxiliary Machinery § 182.330 Pressure vessels. All unfired pressure vessels must be... unfired pressure vessels must meet the applicable requirements of subchapter F (Marine Engineering) of...

  13. 46 CFR 169.249 - Pressure vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Pressure vessels. 169.249 Section 169.249 Shipping COAST... and Certification Inspections § 169.249 Pressure vessels. Pressure vessels must meet the requirements of part 54 of this chapter. The inspection procedures for pressure vessels are contained in subpart...

  14. Contact-inhibited chemotaxis in de novo and sprouting blood-vessel growth.

    Directory of Open Access Journals (Sweden)

    Roeland M H Merks

    2008-09-01

    Full Text Available Blood vessels form either when dispersed endothelial cells (the cells lining the inner walls of fully formed blood vessels organize into a vessel network (vasculogenesis, or by sprouting or splitting of existing blood vessels (angiogenesis. Although they are closely related biologically, no current model explains both phenomena with a single biophysical mechanism. Most computational models describe sprouting at the level of the blood vessel, ignoring how cell behavior drives branch splitting during sprouting. We present a cell-based, Glazier-Graner-Hogeweg model (also called Cellular Potts Model simulation of the initial patterning before the vascular cords form lumens, based on plausible behaviors of endothelial cells. The endothelial cells secrete a chemoattractant, which attracts other endothelial cells. As in the classic Keller-Segel model, chemotaxis by itself causes cells to aggregate into isolated clusters. However, including experimentally observed VE-cadherin-mediated contact inhibition of chemotaxis in the simulation causes randomly distributed cells to organize into networks and cell aggregates to sprout, reproducing aspects of both de novo and sprouting blood-vessel growth. We discuss two branching instabilities responsible for our results. Cells at the surfaces of cell clusters attempting to migrate to the centers of the clusters produce a buckling instability. In a model variant that eliminates the surface-normal force, a dissipative mechanism drives sprouting, with the secreted chemical acting both as a chemoattractant and as an inhibitor of pseudopod extension. Both mechanisms would also apply if force transmission through the extracellular matrix rather than chemical signaling mediated cell-cell interactions. The branching instabilities responsible for our results, which result from contact inhibition of chemotaxis, are both generic developmental mechanisms and interesting examples of unusual patterning instabilities.

  15. Blood Vessel-Derived Acellular Matrix for Vascular Graft Application

    Directory of Open Access Journals (Sweden)

    Luigi Dall’Olmo

    2014-01-01

    Full Text Available To overcome the issues connected to the use of autologous vascular grafts and artificial materials for reconstruction of small diameter (<6 mm blood vessels, this study aimed to develop acellular matrix- (AM- based vascular grafts. Rat iliac arteries were decellularized by a detergent-enzymatic treatment, whereas endothelial cells (ECs were obtained through enzymatic digestion of rat skin followed by immunomagnetic separation of CD31-positive cells. Sixteen female Lewis rats (8 weeks old received only AM or previously in vitro reendothelialized AM as abdominal aorta interposition grafts (about 1 cm. The detergent-enzymatic treatment completely removed the cellular part of vessels and both MHC class I and class II antigens. One month after surgery, the luminal surface of implanted AMs was partially covered by ECs and several platelets adhered in the areas lacking cell coverage. Intimal hyperplasia, already detected after 1 month, increased at 3 months. On the contrary, all grafts composed by AM and ECs were completely covered at 1 month and their structure was similar to that of native vessels at 3 months. Taken together, our findings show that prostheses composed of AM preseeded with ECs could be a promising approach for the replacement of blood vessels.

  16. Design features of the KSTAR in-vessel control coils

    International Nuclear Information System (INIS)

    Kim, H.K.; Yang, H.L.; Kim, G.H.; Kim, Jin-Yong; Jhang, Hogun; Bak, J.S.; Lee, G.S.

    2009-01-01

    In-vessel control coils (IVCCs) are to be used for the fast plasma position control, field error correction (FEC), and resistive wall mode (RWM) stabilization for the Korea Superconducting Tokamak Advanced Research (KSTAR) device. The IVCC system comprises 16 segments to be unified into a single set to achieve following remarkable engineering advantages; (1) enhancement of the coil system reliability with no welding or brazing works inside the vacuum vessel, (2) simplification in fabrication and installation owing to coils being fabricated outside the vacuum vessel and installed after device assembly, and (3) easy repair and maintenance of the coil system. Each segment is designed in 8 turns coil of 32 mm x 15 mm rectangular oxygen free high conductive copper with a 7 mm diameter internal coolant hole. The conductors are enclosed in 2 mm thick Inconel 625 rectangular welded vacuum jacket with epoxy/glass insulation. Structural analyses were implemented to evaluate structural safety against electromagnetic loads acting on the IVCC for the various operation scenarios using finite element analysis. This paper describes the design features and structural analysis results of the KSTAR in-vessel control coils.

  17. Blood vessel classification into arteries and veins in retinal images

    Science.gov (United States)

    Kondermann, Claudia; Kondermann, Daniel; Yan, Michelle

    2007-03-01

    The prevalence of diabetes is expected to increase dramatically in coming years; already today it accounts for a major proportion of the health care budget in many countries. Diabetic Retinopathy (DR), a micro vascular complication very often seen in diabetes patients, is the most common cause of visual loss in working age population of developed countries today. Since the possibility of slowing or even stopping the progress of this disease depends on the early detection of DR, an automatic analysis of fundus images would be of great help to the ophthalmologist due to the small size of the symptoms and the large number of patients. An important symptom for DR are abnormally wide veins leading to an unusually low ratio of the average diameter of arteries to veins (AVR). There are also other diseases like high blood pressure or diseases of the pancreas with one symptom being an abnormal AVR value. To determine it, a classification of vessels as arteries or veins is indispensable. As to our knowledge despite the importance there have only been two approaches to vessel classification yet. Therefore we propose an improved method. We compare two feature extraction methods and two classification methods based on support vector machines and neural networks. Given a hand-segmentation of vessels our approach achieves 95.32% correctly classified vessel pixels. This value decreases by 10% on average, if the result of a segmentation algorithm is used as basis for the classification.

  18. Molten material-containing vessel

    International Nuclear Information System (INIS)

    Akagawa, Katsuhiko

    1998-01-01

    The molten material-containing vessel of the present invention comprises a vessel main body having an entrance opened at the upper end, a lid for closing the entrance, an outer tube having an upper end disposed at the lower surface of the lid, extended downwardly and having an closed lower end and an inner tube disposed coaxially with the outer tube. When a molten material is charged from the entrance to the inside of the vessel main body of the molten material-containing vessel and the entrance is closed by the lid, the outer tube and the inner tube are buried in the molten material in the vessel main body, accordingly, a fluid having its temperature elevated by absorption of the heat of the molten material rises along the inner circumferential surface of the outer tube, abuts against the lower surface of the lid and cooled by exchanging heat with the lid and forms a circulating flow. Since the heat in the molten material is continuously absorbed by the fluid, transferred to the lid and released from the lid to the atmospheric air, heat releasing efficiency can be improved compared with conventional cases. (N.H.)

  19. Vacuum vessel for thermonuclear device

    International Nuclear Information System (INIS)

    Kikuchi, Mitsuru; Nagashima, Keisuke; Suzuki, Masaru; Onozuka, Masaki.

    1997-01-01

    A vacuum vessel main body and structural members at the inside and the outside of the vacuum vessel main body are constituted by structural materials activated by irradiation of neutrons from plasmas such as stainless steels. Shielding members comprising tungsten or molybdenum are disposed on the surface of the vacuum vessel main body and the structural members of the inside and the outside of the main body. The shielding members have a function also as first walls or a seat member for the first walls. Armor tiles may be disposed to the shielding members. The shielding members and the armor tiles are secured to a securing seat member disposed, for example, to an inner plate of the vacuum vessel main body by bolts. Since the shielding members are disposed, it is not necessary to constitute the vacuum vessel main body and the structural members at the inside and the outside thereof by using a low activation material which is less activated, such as a titanium alloy. (I.N.)

  20. Accuracy of Motor Axon Regeneration Across Autograft, Single Lumen, and Multichannel Poly(lactic-co-glycolic Acid) (PLGA) Nerve Tubes

    Science.gov (United States)

    de Ruiter, Godard C.; Spinner, Robert J.; Malessy, Martijn J. A.; Moore, Michael J.; Sorenson, Eric J.; Currier, Bradford L.; Yaszemski, Michael J.; Windebank, Anthony J.

    2012-01-01

    Objective Accuracy of motor axon regeneration becomes an important issue in the development of a nerve tube for motor nerve repair. Dispersion of regeneration across the nerve tube may lead to misdirection and polyinnervation. In this study, we present a series of methods to investigate the accuracy of regeneration, which we used to compare regeneration across autografts and single lumen poly(lactic-co-glycolic acid) (PLGA) nerve tubes. We also present the concept of the multichannel nerve tube that may limit dispersion by separately guiding groups of regenerating axons. Methods Simultaneous tracing of the tibial and peroneal nerves with fast blue (FB) and diamidino yellow (DY), 8 weeks after repair of a 1-cm nerve gap in the rat sciatic nerve, was performed to determine the percentage of double-projecting motoneurons. Sequential tracing of the peroneal nerve with DY 1 week before and FB 8 weeks after repair was performed to determine the percentage of correctly directed peroneal motoneurons. Results In the cases in which there was successful regeneration across single lumen nerve tubes, more motoneurons had double projections to both the tibial and peroneal nerve branches after single lumen nerve tube repair (21.4%) than after autograft repair (5.9%). After multichannel nerve tube repair, this percentage was slightly reduced (16.9%), although not significantly. The direction of regeneration was nonspecific after all types of repair. Conclusion Retrograde tracing techniques provide new insights into the process of regeneration across nerve tubes. The methods and data presented in this study can be used as a basis in the development of a nerve tube for motor nerve repair. PMID:18728579

  1. Poor symptom control is associated with reduced CT scan segmental airway lumen area in smokers with asthma.

    Science.gov (United States)

    Thomson, Neil C; Chaudhuri, Rekha; Spears, Mark; Messow, Claudia-Martina; MacNee, William; Connell, Martin; Murchison, John T; Sproule, Michael; McSharry, Charles

    2015-03-01

    Cigarette smoking is associated with worse symptoms in asthma and abnormal segmental airways in healthy subjects. We tested the hypothesis that current symptom control in smokers with asthma is associated with altered segmental airway dimensions measured by CT scan. In 93 subjects with mild, moderate, and severe asthma (smokers and never smokers), we recorded Asthma Control Questionnaire-6 (ACQ-6) score, spirometry (FEV1; forced expiratory flow rate, midexpiratory phase [FEF(25%-75%)]), residual volume (RV), total lung capacity (TLC), and CT scan measures of the right bronchial (RB) and left bronchial (LB) segmental airway dimensions (wall thickness, mm; lumen area, mm²) in the RB3/LB3, RB6/LB6, and RB10/LB10 (smaller) airways. The CT scan segmental airway (RB10 and LB10) lumen area was reduced in smokers with asthma compared with never smokers with asthma; RB10, 16.6 mm² (interquartile range, 12.4-19.2 mm²) vs 19.6 mm² (14.7-24.2 mm²) (P = .01); LB10, 14.8 mm² (12.1-19.0 mm²) vs 19.9 mm² (14.5-25.0 mm²) (P = .003), particularly in severe disease, with no differences in wall thickness or in larger airway (RB3 and LB3) dimensions. In smokers with asthma, a reduced lumen area in fifth-generation airways (RB10 or LB10) was associated with poor symptom control (higher ACQ-6 score) (-0.463 [-0.666 to -0.196], P = .001, and -0.401 [-0.619 to -0.126], P = .007, respectively) and reduced postbronchodilator FEF(25%-75%) (0.521 [0.292-0.694], P smokers with asthma compared with never smokers with asthma, particularly in severe disease, and is associated with worse current symptom control and small airway dysfunction.

  2. Mockup Small-Diameter Air Distribution System

    Energy Technology Data Exchange (ETDEWEB)

    A. Poerschke and A. Rudd

    2016-05-01

    This report investigates the feasibility of using a home-run manifold small-diameter duct system to provide space conditioning air to individual thermal zones in a low-load home. This compact layout allows duct systems to be brought easily within conditioned space via interior partition walls. Centrally locating the air hander unit in the house significantly reduces duct lengths. The plenum box is designed so that each connected duct receives an equal amount of airflow, regardless of the duct position on the box. Furthermore, within a reasonable set of length restrictions, each duct continues to receive similar airflow. The design method uses an additive approach to reach the total needed zonal airflow. Once the cubic feet per minute needed to satisfy the thermal load of a zone has been determined, the total number of duct runs to a zone can be calculated by dividing the required airflow by the standard airflow from each duct. The additive approach greatly simplifies the design effort and reduces the potential for duct design mistakes to be made. Measured results indicate that this plenum design can satisfy the heating load. However, the total airflow falls short of satisfying the cooling load in a hypothetical building. Static pressure inside the plenum box of 51.5 Pa limited the total airflow of the attached mini-split heat pump blower, thus limiting the total thermal capacity. Fan energy consumption is kept to 0.16 to 0.22 watt/CFM by using short duct runs and smooth duct material.

  3. Determining the best recipient vessel site for autologous microsurgical breast reconstruction with DIEP flaps: An anatomical study.

    Science.gov (United States)

    Lhuaire, Martin; Hivelin, Mikael; Dramé, Moustapha; Abrahams, Peter; Kianmanesh, Reza; Fontaine, Christian; Lantieri, Laurent

    2017-06-01

    The deep inferior epigastric perforator (DIEP) flap is a reliable and reproducible technique for autologous microsurgical breast reconstruction. Several recipient vessels sites for microvascular anastomosis have been described such as the internal thoracic vessels, the thoracodorsal vessels, and the circumflex scapular vessels. Nonetheless, the choice of the recipient site depends mainly on individual operator's experience and preferences, and currently the best recipient vessel site is under debate. This anatomical observational study aimed to determine whether anatomy could address this dilemma by determining the best vessel diameter to match the donor with these three recipient sites. Our series reports 80 dissections of the three anatomical regions of interest. Forty formalin-preserved female cadavers were dissected bilaterally. Internal vessels diameter measurements were recorded with a vascular gauge ranging from 1.0 to 5.0 mm with successive half-millimeter graduations. The median diameter of the deep inferior epigastric (DIEA), internal thoracic (ITA), circumflex scapular (CSA), and thoracodorsal arteries (TDA) were: 2.0, 2.5, 2.5, and 1.5 mm, respectively. The median diameter of the deep inferior epigastric, internal thoracic, circumflex scapular, and thoracodorsal veins were: 3.0, 3.0, 3.0, and 2.5 mm, respectively. At the individual level, the perfect match between DIEA and ITA was significantly more frequent than between DIEA and TDA (p = 0.002), and it was more frequent between DIEA and CSA than between DIEA and TDA (p = 0.009). This study supports the use of the internal thoracic pedicle as the first recipient vessel choice, which should be considered, at least anatomically, as the best one with the closest diameter matching with the donor pedicle. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  4. Body diameters in 3 - 6 years old children from Plovdiv

    Directory of Open Access Journals (Sweden)

    Tineshev Slavi

    2013-01-01

    Full Text Available The purpose of the research is to analyze the body diameters in 3-6 year old children. The biacromial diameters were taken as well as the two chest diameters, the bicristal and bitrohanterial diameters in 316 children (157 boys and 159 girls 3, 4, 5 and 6 years of age attending kindergarten in Plovdiv. The analysis shows that all diameters, with the exception of the bitrohanterial have higher values in boys. The absolute year's increment of the diameters is greater in girls. The growth velocity of the researched features is greatest at the age of 3-4 and 4-5, decreasing at different rates for the different features at the age of 5-6. The only exception is the sagittal chest diameter in both sexes and the bitrohanterial diameters in girls.

  5. Vertical CO2 release experiments from a 1 liter high pressure vessel

    NARCIS (Netherlands)

    Hulsbosch-Dam, C.; Jong, A. de; Zevenbergen, J.; Peeters, R.; Spruijt, M.

    2013-01-01

    High-speed CO2 release experiments from a pressurized vessel have been conducted for a range of storage pressures nozzle diameters. The experiments are conducted to validate and develop models for accidental releases of CO2 during transport. In cooperation with DNV-KEMA lab (Groningen, The

  6. Prediction of Lumen Output and Chromaticity Shift in LEDs Using Kalman Filter and Extended Kalman Filter Based Models

    Energy Technology Data Exchange (ETDEWEB)

    Lall, Pradeep; Wei, Junchao; Davis, J Lynn

    2014-06-24

    Abstract— Solid-state lighting (SSL) luminaires containing light emitting diodes (LEDs) have the potential of seeing excessive temperatures when being transported across country or being stored in non-climate controlled warehouses. They are also being used in outdoor applications in desert environments that see little or no humidity but will experience extremely high temperatures during the day. This makes it important to increase our understanding of what effects high temperature exposure for a prolonged period of time will have on the usability and survivability of these devices. Traditional light sources “burn out” at end-of-life. For an incandescent bulb, the lamp life is defined by B50 life. However, the LEDs have no filament to “burn”. The LEDs continually degrade and the light output decreases eventually below useful levels causing failure. Presently, the TM-21 test standard is used to predict the L70 life of LEDs from LM-80 test data. Several failure mechanisms may be active in a LED at a single time causing lumen depreciation. The underlying TM-21 Model may not capture the failure physics in presence of multiple failure mechanisms. Correlation of lumen maintenance with underlying physics of degradation at system-level is needed. In this paper, Kalman Filter (KF) and Extended Kalman Filters (EKF) have been used to develop a 70-percent Lumen Maintenance Life Prediction Model for LEDs used in SSL luminaires. Ten-thousand hour LM-80 test data for various LEDs have been used for model development. System state at each future time has been computed based on the state space at preceding time step, system dynamics matrix, control vector, control matrix, measurement matrix, measured vector, process noise and measurement noise. The future state of the lumen depreciation has been estimated based on a second order Kalman Filter model and a Bayesian Framework. Life prediction of L70 life for the LEDs used in SSL luminaires from KF and EKF based models have

  7. The Effects of Distention and Obstruction on the Accumulation of Fluid in the Lumen of Small Bowel of Dogs

    Science.gov (United States)

    Mishra, Nand K.; Appert, Hubert E.; Howard, John M.

    1974-01-01

    Fluid accumulation in either the obstructed upper or lower intestinal segments of the dog was found in most animals to be negligible. Distention pressures of 25 cm of water tended to reduce fluid accumulation within the intestinal lumen. These studies suggest that if the dog is comparable to man, the intraluminal accumulation of fluid in the obstructed small bowel of man might be due to alterations in blood supply to the intestine, rather than to obstruction per se, or the accumulated fluid originates proximal to the jejunum. PMID:4419581

  8. Dynamics of micro-bubble sonication inside a phantom vessel

    KAUST Repository

    Qamar, Adnan

    2013-01-10

    A model for sonicated micro-bubble oscillations inside a phantom vessel is proposed. The model is not a variant of conventional Rayleigh-Plesset equation and is obtained from reduced Navier-Stokes equations. The model relates the micro-bubble oscillation dynamics with geometric and acoustic parameters in a consistent manner. It predicts micro-bubble oscillation dynamics as well as micro-bubble fragmentation when compared to the experimental data. For large micro-bubble radius to vessel diameter ratios, predictions are damped, suggesting breakdown of inherent modeling assumptions for these cases. Micro-bubble response with acoustic parameters is consistent with experiments and provides physical insight to the micro-bubble oscillation dynamics.

  9. 19 CFR 4.5 - Government vessels.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government vessel...

  10. [Effects of high intensity focused ultrasound with SonoVue on blood vessels pathological examinations].

    Science.gov (United States)

    Qin, Yan; Bai, Jin; Li, Faqi; Wang, Zhibiao

    2010-12-01

    The injury of tumor blood vessels will break up the nutrition supply for the tumor. In this paper, we investigated the effects exerted by high intensity focused ultrasound (HIFU) combined with ultrasound microbubble agent on blood vessels. Ultrasound diagnosis was used to find the goat hepatic blood vessels each being approximately 3mm in diameter. HIFU was focused on the blood vessels. The acoustic power was 250W; HIFU irradiating Mode was line scan (the length of the line: 10 mm; speed: 3 mm/s; irradiating time: 30s). In the experimental group, 0.03 ml/kg SonoVue was injected into the goat before HIFU irradiation,while normal saline was given to the control group. The goats were killed at 24h after HIFU irradiation, then goat liver tissues and blood vessels of target area were taken out. HE staining and Victoria's blue and Ponceau's staining of tissue section showed that the endothelial cells of blood vessels dropped off and became necrosed, and the continuity of blood vessels was interrupted. HIFU combined with SonoVue will damage large blood vessels on HIFU focus, but there is no evident discrepancy between the group with SonoVue and the group without SonoVue.

  11. Distribution of Different Sized Ocular Surface Vessels in Diabetics and Normal Individuals.

    Science.gov (United States)

    Banaee, Touka; Pourreza, Hamidreza; Doosti, Hassan; Abrishami, Mojtaba; Ehsaei, Asieh; Basiry, Mohsen; Pourreza, Reza

    2017-01-01

    To compare the distribution of different sized vessels using digital photographs of the ocular surface of diabetic and normal individuals. In this cross-sectional study, red-free conjunctival photographs of diabetic and normal individuals, aged 30-60 years, were taken under defined conditions and analyzed using a Radon transform-based algorithm for vascular segmentation. The image areas occupied by vessels (AOV) of different diameters were calculated. The main outcome measure was the distribution curve of mean AOV of different sized vessels. Secondary outcome measures included total AOV and standard deviation (SD) of AOV of different sized vessels. Two hundred and sixty-eight diabetic patients and 297 normal (control) individuals were included, differing in age (45.50 ± 5.19 vs. 40.38 ± 6.19 years, P distribution curves of mean AOV differed between patients and controls (smaller AOV for larger vessels in patients; P distribution curve of vessels compared to controls. Presence of diabetes mellitus is associated with contraction of larger vessels in the conjunctiva. Smaller vessels dilate with diabetic retinopathy. These findings may be useful in the photographic screening of diabetes mellitus and retinopathy.

  12. Pressure vessel for nuclear reactors

    International Nuclear Information System (INIS)

    Stoll, A.

    1976-01-01

    The invention relates to a pressure vessel which can be used for nuclear reactors and for chemical processing technologies. A grid of walls welded to each other, which is installed in the interior of the pressure vessel, is so attached to an outer jacket at several edges, that these edges exert a force on the wall of the vessel directed towards the interior. Only the out jacket resists the differential between the inner and outer pressures; the welded walls in the interior do not have to sustain any differential pressure. They create a larger number of inner spaces (or tubes) which can be individually accessible and each of which has a terminal element. (UWI) [de

  13. Emergency venting of pressure vessels

    International Nuclear Information System (INIS)

    Steinkamp, H.

    1995-01-01

    With the numerical codes developed for safety analysis the venting of steam vessel can be simulated. ATHLET especially is able to predict the void fraction depending on the vessel height. Although these codes contain a one-dimensional model they allow the description of complex geometries due to the detailed nodalization of the considered apparatus. In chemical reactors, however, the venting process is not only influenced by the flashing behaviour but additionally by the running chemical reaction in the vessel. Therefore the codes used for modelling have to consider the kinetics of the chemical reaction. Further multi-component systems and dissolving processes have to be regarded. In order to preduct the fluid- and thermodynamic process it could be helpful to use 3-dimensional codes in combination with the one-dimensional codes as used in nuclear industry to get a more detailed describtion of the running processes. (orig./HP)

  14. LARCODEMS: more than a proven destoning vessel on South African coals?

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, S.T.; Woodman, J.R.; Peatfield, D.M. [LTA Process Engineering Limited (South Africa)

    1998-12-31

    LARCODEMS was originally developed by British Coal as a dense medium vessel capable of efficiently and cost effectively treating a deslimed -100+0.5 mm feedstock. Twelve vessels were installed at British coal mines. The operating principle of the vessel is the utilization of centrifugal forces within the vessel to effect an efficient separation of clean coal and reject. Control parameters for optimal performance are vessel medium inlet pressure, raw coal feed rate and medium density control. This paper deals with further applications of the LARCODEMS technology on South African coals, and the associated advances in design to cater for differences in coal characteristics. The first application of the technology outside the UK took place at Ingwe Coal Corporation`s Middleburg Mine Services South Section (Duhva). The twin module HMS (heavy medium separation) sections treat 350 t/h per module of -100+20/12 mm raw coal through the 1200 mm diameter vessel, in a high gravity `de-stoning` application. Results of the plant performance test are presented. The second LARCODEMS plant in South Africa was successfully commissioned at Tavistock Colliery`s No. 4 Seam Plant. This signalled a departure from the `de-stoner` concept, and was the world`s first 1,000 mm diameter vessel. The Tavistock vessel application is a -80+10 mm wash at 1.65 RD to produce an overall target CV of 26.8 MJ/kg (air dried). The plant performance test is discussed, and the results of further test work carried out at lower density on various discrete size fractions are presented. Innovations in vessel and platework design to improve availability and maintenance have occurred and are discussed. A look ahead at proposed applications on both coal and iron ore is presented. 6 figs.

  15. Lumbar Vertebral Canal Diameters in Adult Ugandan Skeletons ...

    African Journals Online (AJOL)

    The midsagittal, transverse diameters of the lumbar vertebral canal and the anteroposterior diameter of the inferior vertebral notch were measured using an electronic digital caliper. Collected data was analyzed using SPSS 12.0 computer program. Results and discussion: In both sexes, the midsagittal diameter of the canal ...

  16. Aortic Root Diameter and Longitudinal Blood Pressure Tracking

    OpenAIRE

    Ingelsson, Erik; Pencina, Michael J.; Levy, Daniel; Aragam, Jayashri; Mitchell, Gary F.; Benjamin, Emelia J.; Vasan, Ramachandran S.

    2008-01-01

    Proximal aortic diameter, including aortic root (AoR) diameter, has been inversely related to pulse pressure (PP) in cross-sectional studies. So, investigators have hypothesized that a smaller AoR diameter may increase risk of developing hypertension. Prospective studies are lacking to test this hypothesis.

  17. 46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Drainage of cockpit vessels, well deck vessels, and open... PASSENGERS CONSTRUCTION AND ARRANGEMENT Drainage and Watertight Integrity of Weather Decks § 116.1120 Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck...

  18. The Role of Endothelial Ca2+ Signaling in Neurovascular Coupling: A View from the Lumen

    Directory of Open Access Journals (Sweden)

    Germano Guerra

    2018-03-01

    Full Text Available Background: Neurovascular coupling (NVC is the mechanism whereby an increase in neuronal activity (NA leads to local elevation in cerebral blood flow (CBF to match the metabolic requirements of firing neurons. Following synaptic activity, an increase in neuronal and/or astrocyte Ca2+ concentration leads to the synthesis of multiple vasoactive messengers. Curiously, the role of endothelial Ca2+ signaling in NVC has been rather neglected, although endothelial cells are known to control the vascular tone in a Ca2+-dependent manner throughout peripheral vasculature. Methods: We analyzed the literature in search of the most recent updates on the potential role of endothelial Ca2+ signaling in NVC. Results: We found that several neurotransmitters (i.e., glutamate and acetylcholine and neuromodulators (e.g., ATP can induce dilation of cerebral vessels by inducing an increase in endothelial Ca2+ concentration. This, in turn, results in nitric oxide or prostaglandin E2 release or activate intermediate and small-conductance Ca2+-activated K+ channels, which are responsible for endothelial-dependent hyperpolarization (EDH. In addition, brain endothelial cells express multiple transient receptor potential (TRP channels (i.e., TRPC3, TRPV3, TRPV4, TRPA1, which induce vasodilation by activating EDH. Conclusions: It is possible to conclude that endothelial Ca2+ signaling is an emerging pathway in the control of NVC.

  19. The Role of Endothelial Ca2+ Signaling in Neurovascular Coupling: A View from the Lumen.

    Science.gov (United States)

    Guerra, Germano; Lucariello, Angela; Perna, Angelica; Botta, Laura; De Luca, Antonio; Moccia, Francesco

    2018-03-21

    Neurovascular coupling (NVC) is the mechanism whereby an increase in neuronal activity (NA) leads to local elevation in cerebral blood flow (CBF) to match the metabolic requirements of firing neurons. Following synaptic activity, an increase in neuronal and/or astrocyte Ca 2+ concentration leads to the synthesis of multiple vasoactive messengers. Curiously, the role of endothelial Ca 2+ signaling in NVC has been rather neglected, although endothelial cells are known to control the vascular tone in a Ca 2+ -dependent manner throughout peripheral vasculature. We analyzed the literature in search of the most recent updates on the potential role of endothelial Ca 2+ signaling in NVC. We found that several neurotransmitters (i.e., glutamate and acetylcholine) and neuromodulators (e.g., ATP) can induce dilation of cerebral vessels by inducing an increase in endothelial Ca 2+ concentration. This, in turn, results in nitric oxide or prostaglandin E2 release or activate intermediate and small-conductance Ca 2+ -activated K⁺ channels, which are responsible for endothelial-dependent hyperpolarization (EDH). In addition, brain endothelial cells express multiple transient receptor potential (TRP) channels (i.e., TRPC3, TRPV3, TRPV4, TRPA1), which induce vasodilation by activating EDH. It is possible to conclude that endothelial Ca 2+ signaling is an emerging pathway in the control of NVC.

  20. The behaviour of the pulmonary vessels on X-ray films of children with asthma bronchiale

    International Nuclear Information System (INIS)

    Hegenbarth, R.; Toeroek, M.; Medizinische Hochschule Hannover

    1986-01-01

    On X-ray films of 51 children with asthma bronchiale the authors determined the vascular diameter of the right ascending pulmonary artery, the right vein of the upper lobe, and the peripheral vessels in the upper and lower pulmonary fields at an exactly defined distance from the hilus point, and compared these data with those of a control group of 143 healthy children. During the asthma attack the width of the right descending pulmonary artery and of the vein of the upper lobe corresponded to the values of the control group, whereas the vascular diameters in the upper and lower fields were clearly narrowed. Moreover, in most of the asthmatic children the authors found arc-shaped vessels and irregularly occluded vessels in the periphery of the lungs. (orig.) [de

  1. Stress analysis of pressure vessels

    International Nuclear Information System (INIS)

    Kim, B.K.; Song, D.H.; Son, K.H.; Kim, K.S.; Park, K.B.; Song, H.K.; So, J.Y.

    1979-01-01

    This interim report contains the results of the effort to establish the stress report preparation capability under the research project ''Stress analysis of pressure vessels.'' 1978 was the first year in this effort to lay the foundation through the acquisition of SAP V structural analysis code and a graphic terminal system for improved efficiency of using such code. Software programming work was developed in pre- and post processing, such as graphic presentation of input FEM mesh geometry and output deformation or mode shope patterns, which was proven to be useful when using the FEM computer code. Also, a scheme to apply fracture mechanics concept was developed in fatigue analysis of pressure vessels. (author)

  2. Vessel dilatation in coronary angiograms

    Energy Technology Data Exchange (ETDEWEB)

    Hinterauer, L.; Goebel, N.

    1983-11-01

    Amongst 166 patients with aneurysms, ectasia or megaloarteries shown on coronary angiograms, 86.1% had dilated vessels as part of generalised coronary sclerosis (usually in patients with three-vessel disease). In 9%, dilatation was of iatrogenic origin and in 4.8% it was idiopathic. One patient had Marfan's syndrome. Amongst 9 000 patients, there were eight with megalo-arteries without stenosis; six of these had atypical angina and three suffered an infarct. Patients with definite dilatation of the coronary artery and stagnation of contrast flow required treatment.

  3. Vessel dilatation in coronary angiograms

    International Nuclear Information System (INIS)

    Hinterauer, L.; Goebel, N.

    1983-01-01

    Amongst 166 patients with aneurysms, ectasia or megaloarteries shown on coronary angiograms, 86.1% had dilated vessels as part of generalised coronary sclerosis (usually in patients with three-vessel disease). In 9%, dilatation was of iatrogenic origin and in 4.8% it was idiopathic. One patient had Marfan's syndrome. Amongst 9 000 patients, there were eight with megalo-arteries without stenosis; six of these had atypical angina and three suffered an infarct. Patients with definite dilatation of the coronary artery and stagnation of contrast flow required treatment. (orig.) [de

  4. Tissue-Engineered Vascular Graft of Small Diameter Based on Electrospun Polylactide Microfibers

    Directory of Open Access Journals (Sweden)

    P. V. Popryadukhin

    2017-01-01

    Full Text Available Tubular vascular grafts 1.1 mm in diameter based on poly(L-lactide microfibers were obtained by electrospinning. X-ray diffraction and scanning electron microscopy data demonstrated that the samples treated at T=70°C for 1 h in the fixed state on a cylindrical mandrel possessed dense fibrous structure; their degree of crystallinity was approximately 44%. Strength and deformation stability of these samples were higher than those of the native blood vessels; thus, it was possible to use them in tissue engineering as bioresorbable vascular grafts. The experiments on including implantation into rat abdominal aorta demonstrated that the obtained vascular grafts did not cause pathological reactions in the rats; in four weeks, inner side of the grafts became completely covered with endothelial cells, and fibroblasts grew throughout the wall. After exposure for 12 weeks, resorption of PLLA fibers started, and this process was completed in 64 weeks. Resorbed synthetic fibers were replaced by collagen and fibroblasts. At that time, the blood vessel was formed; its neointima and neoadventitia were close to those of the native vessel in structure and composition.

  5. Dynamics of retinal vessel response to flicker light in glaucoma patients and ocular hypertensives.

    Science.gov (United States)

    Gugleta, K; Kochkorov, A; Waldmann, N; Polunina, A; Katamay, R; Flammer, J; Orgul, S

    2012-04-01

    To analyze dynamics of retinal vessel dilation response to flicker light in patients with glaucoma and ocular hypertension. Response to flicker light was measured in retinal vessels by means of Retinal Vessel Analyzer. After the baseline 50 seconds long diameter recording of inferior and superior temporal artery and vein, three flicker stimulations of 20 seconds duration was applied, with a 80 seconds break in between. Area under the curve of the vessel diameter (AUC) was compared during 3 flicker periods in the open angle glaucoma patients group (POAG, n = 47) and ocular hypertensives (OHT, n = 46) and age-matched healthy controls (n = 56) POAG eyes demonstrated smaller response of all vessels to flicker light in general than the other two groups (p = 0.0008), but the response dynamics was significantly different between the groups (p = 0.038), showing in three flicker periods a delayed increasing response in the POAG and OHT groups, and remaining stable in healthy subjects. General vessel response to flicker light was decreased in POAG patients despite the slow improvement in repeated flicker stimulation, indicating an altered response pattern.

  6. Par1b links lumen polarity with LGN-NuMA positioning for distinct epithelial cell division phenotypes.

    Science.gov (United States)

    Lázaro-Diéguez, Francisco; Cohen, David; Fernandez, Dawn; Hodgson, Louis; van Ijzendoorn, Sven C D; Müsch, Anne

    2013-10-28

    Columnar epithelia establish their luminal domains and their mitotic spindles parallel to the basal surface and undergo symmetric cell divisions in which the cleavage furrow bisects the apical domain. Hepatocyte lumina interrupt the lateral domain of neighboring cells perpendicular to two basal domains and their cleavage furrow rarely bifurcates the luminal domains. We determine that the serine/threonine kinase Par1b defines lumen position in concert with the position of the astral microtubule anchoring complex LGN-NuMA to yield the distinct epithelial division phenotypes. Par1b signaling via the extracellular matrix (ECM) in polarizing cells determined RhoA/Rho-kinase activity at cell-cell contact sites. Columnar MDCK and Par1b-depleted hepatocytic HepG2 cells featured high RhoA activity that correlated with robust LGN-NuMA recruitment to the metaphase cortex, spindle alignment with the substratum, and columnar organization. Reduced RhoA activity at the metaphase cortex in HepG2 cells and Par1b-overexpressing MDCK cells correlated with a single or no LGN-NuMA crescent, tilted spindles, and the development of lateral lumen polarity.

  7. Impaired small-bowel barrier integrity in the presence of lumenal pancreatic digestive enzymes leads to circulatory shock.

    Science.gov (United States)

    Kistler, Erik B; Alsaigh, Tom; Chang, Marisol; Schmid-Schönbein, Geert W

    2012-08-01

    In bowel ischemia, impaired mucosal integrity may allow intestinal pancreatic enzyme products to become systemic and precipitate irreversible shock and death. This can be attenuated by pancreatic enzyme inhibition in the small-bowel lumen. It is unresolved, however, whether ischemically mediated mucosal disruption is the key event allowing pancreatic enzyme products systemic access and whether intestinal digestive enzyme activity in concert with increased mucosal permeability leads to shock in the absence of ischemia. To test this possibility, the small intestinal lumen of nonischemic rats was perfused for 2 h with either digestive enzymes, a mucin disruption strategy (i.e., mucolytics) designed to increase mucosal permeability, or both, and animals were observed for shock. Digestive enzymes perfused included trypsin, chymotrypsin, elastase, amylase, and lipase. Control (n = 6) and experimental animals perfused with pancreatic enzymes only (n = 6) or single enzymes (n = 3 for each of the five enzyme groups) maintained stable hemodynamics. After mucin disruption using a combination of enteral N-acetylcysteine, atropine, and increased flow rates, rats (n = 6) developed mild hypotension (P shock and increase systemic protease activation in the absence of ischemia, implicating bowel mucin disruption as a key event in early ischemia. Digestive enzymes and their products, if allowed to penetrate the gut wall, may trigger multiorgan failure and death.

  8. Use of GlideScope for double lumen endotracheal tube insertion in an awake patient with difficult airway.

    Science.gov (United States)

    Onrubia, X; Lluch-Oltra, A; Armero, R; Baldó, J

    2014-01-01

    There is scientific evidence that an anticipated difficult airway must be managed with the patient being awake. The GlideScope has been proven to be a useful device to intubate the trachea in some instances when difficult airway is present, and particularly in the awake patient. It has also been used for double lumen tube (DLT) in the anaesthetized patient, but its use with DLT in both circumstances, awake patients with difficult airway has not been described. GlideScope enabled us to achieve accurate local anesthetic spraying and a successful endotracheal intubation with a double lumen tube (DLT) in an awake patient with predicted difficult airway and bronchoaspiration risk. Different ways to resolve cases like this can be found in the anesthetic literature, but we think this could be another option to bear in mind. We also describe a new variation in the maneuver of introducing a DLT into the trachea under GlideScope view as DLT presents with some difficulties when introduced under normal circumstances. This option could add some risk for the patients when used in inexperienced hands and there is not sufficient scientific evidence in the literature to recommend it for all cases. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

  9. Incidental extracolonic findings on bright lumen MR colonography in a population at increased risk for colorectal carcinoma

    International Nuclear Information System (INIS)

    Yusuf, Erlangga; Florie, Jasper; Nio, Chung Yung; Jensch, Sebastian; Nievelstein, Rutger A.J.; Baak, Lubbertus; Stoker, Jaap

    2011-01-01

    Purpose: Incidental extracolonic findings affect patient treatment and cost. Therefore, to consider magnetic resonance colonography (MRC) as a tool for colorectal cancer and polyps screening, more knowledge is needed on extracolonic findings. In this study, we sought to determine the prevalence and the spectrum of extracolonic findings in patients with an increased risk colorectal cancer that underwent bright lumen MRC. Materials and methods: MRC examinations were performed in 210 patients. A gadolinium solution was administered rectally for distension of the colon. Extracolonic findings were scored by two radiologists and classified by using C-RADS Reporting System. All findings (with advice regarding work-up) were reported to the patient's physician and followed up for 4.5 years on average. Results: Extracolonic findings were found in 125 (59.5%) patients. Ten (4.8%) had 'potentially important' findings (C-RADS category E4). Twenty-five patients (11.9%) had 'likely unimportant' findings (E3), 90 (42.8%) had 'clinically unimportant' findings (E2) and 85 (40.5%) had a normal exam (E1). In 14 (6.7%) patients additional work-up was performed for their incidentally discovered lesions. In three of them surgery was performed. After work-up, only in two (1.0%) patients a malignancy was found. Conclusion: The number of new relevant extracolonic findings is small and the required additional work-up is limited. This should be considered for implementation of 'bright lumen' MRC as a screening tool.

  10. Submillimeter Diameter Poly(Vinyl Alcohol) Vascular Graft Patency in Rabbit Model

    Science.gov (United States)

    Cutiongco, Marie F. A.; Kukumberg, Marek; Peneyra, Jonnathan L.; Yeo, Matthew S.; Yao, Jia Y.; Rufaihah, Abdul Jalil; Le Visage, Catherine; Ho, Jackie Pei; Yim, Evelyn K. F.

    2016-01-01

    Microvascular surgery is becoming a prevalent surgical practice. Replantation, hand reconstruction, orthopedic, and free tissue transfer procedures all rely on microvascular surgery for the repair of venous and arterial defects at the millimeter and submillimeter levels. Often, a vascular graft is required for the procedure as a means to bridge the gap between native arteries. While autologous vessels are desired for their bioactivity and non-thrombogenicity, the tedious harvest process, lack of availability, and caliber or mechanical mismatch contribute to graft failure. Thus, there is a need for an off-the-shelf artificial vascular graft that has low thrombogenic properties and mechanical properties matching those of submillimeter vessels. Poly(vinyl alcohol) hydrogel (PVA) has excellent prospects as a vascular graft due to its bioinertness, low thrombogenicity, high water content, and tunable mechanical properties. Here, we fabricated PVA grafts with submillimeter diameter and mechanical properties that closely approximated those of the rabbit femoral artery. In vitro platelet adhesion and microparticle release assay verified the low thrombogenicity of PVA. A stringent proof-of-concept in vivo test was performed by implanting PVA grafts in rabbit femoral artery with multilevel arterial occlusion. Laser Doppler measurements indicated the improved perfusion of the distal limb after implantation with PVA grafts. Moreover, ultrasound Doppler and angiography verified that the submillimeter diameter PVA vascular grafts remained patent for 2 weeks without the aid of anticoagulant or antithrombotics. Endothelial cells were observed in the luminal surface of one patent PVA graft. The advantageous non-thrombogenic and tunable mechanical properties of PVA that are retained even in the submillimeter diameter dimensions support the application of this biomaterial for vascular replacement in microvascular surgery. PMID:27376059

  11. Development and evaluation of elastomeric hollow fiber membranes as small diameter vascular graft substitutes

    Energy Technology Data Exchange (ETDEWEB)

    Mercado-Pagán, Ángel E.; Kang, Yunqing [Department of Orthopedic Surgery, Stanford University, Stanford, CA (United States); Findlay, Michael W. [Department of Plastic and Reconstructive Surgery, Stanford University, Stanford, CA (United States); University of Melbourne Department of Surgery, Royal Melbourne Hospital, Parkville, VIC (Australia); Yang, Yunzhi, E-mail: ypyang@stanford.edu [Department of Orthopedic Surgery, Stanford University, Stanford, CA (United States); Department of Materials Science and Engineering, Stanford University, Stanford, CA (United States)

    2015-04-01

    Engineering of small diameter (< 6 mm) vascular grafts (SDVGs) for clinical use remains a significant challenge. Here, elastomeric polyester urethane (PEU)-based hollow fiber membranes (HFMs) are presented as an SDVG candidate to target the limitations of current technologies and improve tissue engineering designs. HFMs are fabricated by a simple phase inversion method. HFM dimensions are tailored through adjustments to fabrication parameters. The walls of HFMs are highly porous. The HFMs are very elastic, with moduli ranging from 1–4 MPa, strengths from 1–5 MPa, and max strains from 300–500%. Permeability of the HFMs varies from 0.5–3.5 × 10{sup −6} cm/s, while burst pressure varies from 25 to 35 psi. The suture retention forces of HFMs are in the range of 0.8 to 1.2 N. These properties match those of blood vessels. A slow degradation profile is observed for all HFMs, with 71 to 78% of the original mass remaining after 8 weeks, providing a suitable profile for potential cellular incorporation and tissue replacement. Both human endothelial cells and human mesenchymal stem cells proliferate well in the presence of HFMs up to 7 days. These results demonstrate a promising customizable PEU HFMs for small diameter vascular repair and tissue engineering applications. - Highlights: • Hollow fiber membranes (HFMs) were fabricated and evaluated. • HFM properties could be tailored through adjustments to fabrication parameters. • Properties could match or exceed those of blood vessels. • HFM showed excellent compatibility in vitro. • HFMs have the potential to be used for small diameter vascular grafts.

  12. Commercial Passenger Fishing Vessel Fishery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains the logbook data from U.S.A. Commercial Passenger Fishing Vessels (CPFV) fishing in the U.S.A. EEZ and in waters off of Baja California, from...

  13. The Vessel Schedule Recovery Problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Plum, Christian Edinger Munk; Vaaben, Bo

    Maritime transportation is the backbone of world trade and is accountable for around 3% of the worlds CO2 emissions. We present the Vessel Schedule Recovery Problem (VSRP) to evaluate a given disruption scenario and to select a recovery action balancing the trade off between increased bunker...

  14. Pressure vessel and method therefor

    Science.gov (United States)

    Saunders, Timothy

    2017-09-05

    A pressure vessel includes a pump having a passage that extends between an inlet and an outlet. A duct at the pump outlet includes at least one dimension that is adjustable to facilitate forming a dynamic seal that limits backflow of gas through the passage.

  15. Pressure vessel having continuous sidewall

    Science.gov (United States)

    Simon, Xavier D. (Inventor); Barackman, Victor J. (Inventor)

    2011-01-01

    A spacecraft pressure vessel has a tub member. A sidewall member is coupled to the tub member so that a bottom section of the sidewall member extends from an attachment intersection with the tub member and away from the tub member. The bottom section of the sidewall member receives and transfers a load through the sidewall member.

  16. CT and histopathologic characteristics of lung adenocarcinoma with pure ground-glass nodules 10 mm or less in diameter

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Fang [Chinese PLA General Hospital, Department of Radiology, Beijing (China); Capital Medical University, Department of Radiology, Xuanwu Hospital, Beijing (China); Tian, Shu-ping [Navy General Hospital, Department of Radiology, Beijing (China); Jin, Xin; Jing, Rui; Yang, Yue-qing; Jin, Mei; Zhao, Shao-hong [Chinese PLA General Hospital, Department of Radiology, Beijing (China)

    2017-10-15

    To evaluate CT and histopathologic features of lung adenocarcinoma with pure ground-glass nodule (pGGN) ≤10 mm in diameter. CT appearances of 148 patients (150 lesions) who underwent curative resection of lung adenocarcinoma with pGGN ≤10 mm (25 atypical adenomatous hyperplasias, 42 adenocarcinoma in situs, 38 minimally invasive adenocarcinomas, and 45 invasive pulmonary adenocarcinomas) were analyzed for lesion size, density, bubble-like sign, air bronchogram, vessel changes, margin, and tumour-lung interface. CT characteristics were compared among different histopathologic subtypes. Univariate and multivariate analysis were used to assess the relationship between CT characteristics of pGGN and lesion invasiveness, respectively. There were statistically significant differences among histopathologic subtypes in lesion size, vessel changes, and tumour-lung interface (P<0.05). Univariate analysis revealed significant differences of vessel changes, margin and tumour-lung interface between preinvasive and invasive lesions (P<0.05). Logistic regression analysis showed that the vessel changes, unsmooth margin and clear tumour-lung interface were significant predictive factors for lesion invasiveness, with odds ratios (95% CI) of 2.57 (1.17-5.62), 1.83 (1.25-2.68) and 4.25 (1.78-10.14), respectively. Invasive lesions are found in 55.3% of subcentimeter pGGNs in our cohort. Vessel changes, unsmooth margin, and clear lung-tumour interface may indicate the invasiveness of lung adenocarcinoma with subcentimeter pGGN. (orig.)

  17. The quantitative evaluation of intracranial pressure by optic nerve sheath diameter/eye diameter CT measurement.

    Science.gov (United States)

    Bekerman, Inessa; Sigal, Tal; Kimiagar, Itzhak; Ben Ely, Anna; Vaiman, Michael

    2016-12-01

    The changes of the optic nerve sheath diameter (ONSD) have been used to assess changes of the intracranial pressure for 20 years. The aim of this research was to further quantify the technique of measuring the ONSD for this purpose. Retrospective study of computed tomographic (CT) data of 1766 adult patients with intracranial hypotension (n=134) or hypertension (n=1632) were analyzed. The eyeball transverse diameter (ETD) and ONSD were obtained bilaterally, and the ONSD/ETD ratio was calculated. The ratio was used to calculate the normal ONSD for patients and to estimate the intracranial pressure of the patients before and after the onset of the pathology. Correlation analysis was performed with invasively measured intracranial pressure, the presence or absence of papilledema, sex, and age. In hypotension cases, the ONSD by CT was 3.4±0.7 mm (P=.03 against normative 4.4±0.8 mm). In cases with hypertension, the diameter was 6.9±1.3 (P=.02, with a cutoff value ˃5.5 mm). The ONSD/ETD ratio was 0.29±0.04 against 0.19±0.02 in healthy adults (P=.01). The ONSD and the ONSD/ETD ratio can indicate low intracranial pressure, but quantification is impossible at intracranial pressure less than 13 mm Hg. In elevated intracranial pressure, the ONSD and the ratio provide readings that correspond to readings in millimeters of mercury. The ONSD method, reinforced with additional calculations, may help to indicate a raised intracranial pressure, evaluate its severity quantitatively, and establish quantitative goals for treatment of intracranial hypertension, but the limitations of the method are to be taken into account. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Optics based signal processing methods for intraoperative blood vessel detection and quantification in real time (Conference Presentation)

    Science.gov (United States)

    Chaturvedi, Amal; Shukair, Shetha A.; Le Rolland, Paul; Vijayvergia, Mayank; Subramanian, Hariharan; Gunn, Jonathan W.

    2016-03-01

    Minimally invasive operations require surgeons to make difficult cuts to blood vessels and other tissues with impaired tactile and visual feedback. This leads to inadvertent cuts to blood vessels hidden beneath tissue, causing serious health risks to patients and a non-reimbursable financial burden to hospitals. Intraoperative imaging technologies have been developed, but these expensive systems can be cumbersome and provide only a high-level view of blood vessel networks. In this research, we propose a lean reflectance-based system, comprised of a dual wavelength LED, photodiode, and novel signal processing algorithms for rapid vessel characterization. Since this system takes advantage of the inherent pulsatile light absorption characteristics of blood vessels, no contrast agent is required for its ability to detect the presence of a blood vessel buried deep inside any tissue type (up to a cm) in real time. Once a vessel is detected, the system is able to estimate the distance of the vessel from the probe and the diameter size of the vessel (with a resolution of ~2mm), as well as delineate the type of tissue surrounding the vessel. The system is low-cost, functions in real-time, and could be mounted on already existing surgical tools, such as Kittner dissectors or laparoscopic suction irrigation cannulae. Having been successfully validated ex vivo, this technology will next be tested in a live porcine study and eventually in clinical trials.

  19. Some structural aspects of precapillary vessels.

    Science.gov (United States)

    Hammersen, F; Hammersen, E

    1984-01-01

    According to the present state of the art, the former Chambers-Zweifach conception is no longer tenable as the ubiquitous module of microvascular organization. Any attempt to define the consecutive segments of precapillary vessels in a random collection of sectioned tissues is impaired by the extreme scatter of variations and the lack of additional criteria necessary for a distinct classification. With these inadequacies in mind, arterioles, terminal arterioles, and their precapillary segments (sphincters?) are identified by applying the following parameters: luminal diameter, composition of the subendothelial space, and thickness as well as completeness of the media. Endothelial components of particular functional significance are different types of cytoplasmic filaments and myoendothelial junctions. The former serve as a cytoskeleton and may provide a mechanism to adapt endothelial tensile strength to variations of shearing forces. The latter appear to be sites of firm intercellular attachment and of electrotonic coupling of the endothelium to the underlying smooth-muscle cells. The former unanimously accepted helicoidal arrangement of vascular smooth muscle (VSM) must be modified according to most recent findings, and the tridimensional shape of VSM and its transition to pericyte-like elements remain to be further elucidated. Future effects, from which solutions to the many open problems may be expected, must therefore aim at combined vital-, light-, and electron-microscopic studies of the methodically accessible microvascular beds. This necessity has already been recognized, and first promising steps have been taken.

  20. Vessel tree extraction using locally optimal paths

    DEFF Research Database (Denmark)

    Lo, Pechin Chien Pau; van Ginneken, Bram; de Bruijne, Marleen

    2010-01-01

    This paper proposes a method to extract vessel trees by continually extending detected branches with locally optimal paths. Our approach uses a cost function from a multi scale vessel enhancement filter. Optimal paths are selected based on rules that take into account the geometric characteristics...... of the vessel tree. Experiments were performed on 10 low dose chest CT scans for which the pulmonary vessel trees were extracted. The proposed method is shown to extract a better connected vessel tree and extract more of the small peripheral vessels in comparison to applying a threshold on the output...

  1. Analysis of Gear Wheel-shaft Joint Characterized by Comparable Pitch Diameter and Mounting Diameter

    Directory of Open Access Journals (Sweden)

    J. Ryś

    2003-01-01

    Full Text Available This paper presents the design procedure for a gear wheel-shaft direct frictional joint. The small difference between the operating pitch diameter of the gear and the mounting diameter of the frictional joint is the key feature of the connection. The contact surface of the frictional joint must be placed outside the bottom land of the gear, and the geometry of the joint is limited to the specific type of solutions.The strength analysis is based on the relation between the torque and statistical load intensity of the gear transmission. Several dimensionless parameters are introduced to simplify the calculations. Stress-strain verifying analysis with respect to combined loading, the condition of appropriate load-carrying capacity of the frictional joint and the fatigue strength of the shaft are applied to obtain the relations between the dimensions of the joint and other parameters. The final engineering solution may then be suggested. The approach is illustrated by a numerical example.The proposed procedure can be useful in design projects for small, high-powered modern reducers and new-generation geared motors, in particular when manufactured in various series of types.

  2. Towards cavitation-enhanced permeability in blood vessel on a chip

    Science.gov (United States)

    De Luca, R.; Silvani, G.; Scognamiglio, C.; Sinibaldi, G.; Peruzzi, G.; Chinappi, M.; Kiani, M. F.; Casciola, C. M.

    2017-08-01

    The development of targeted delivery systems releasing pharmaceutical agents directly at the desired site of action may improve their therapeutic efficiency while minimizing damage to healthy tissues, toxicity to the patient and drug waste. In this context, we have developed a bio-inspired microdevice mimicking the tumour microvasculature which represents a valuable tool for assessing the enhancement of blood vessel permeability due to cavitation. This novel system allows us to investigate the effects of ultrasound-driven microbubbles that temporarily open the endothelial intercellular junctions allowing drug to extravasate blood vessels into tumour tissues. The blood vessel on a chip consists of a tissue chamber and two independent vascular channels (width 200 µm, height 100 µm, length 2762 µm) cultured with endothelial cells placed side-by-side and separated by a series of 3 µm pores. Its geometry and dimensions mimic the three-dimensional morphology, size and flow characteristics of microvessels in vivo. The early stage of this project had a twofold objective: 1. To define the protocol for culturing of Human Umbilical Vein Endothelial Cells (HUVECs) within the vascular channel; 2. To develop a fluorescence based microscopy technique for measuring permeability. We have developed a reliable and reproducible protocol to culture endothelial cells within the artificial vessels in a realistic manner: HUVECs show the typical elongated shape in the direction of flow, exhibit tight junction formation and form a continuous layer with a central lumen that completely covers the channels wall. As expected, the permeability of cell-free device is higher than the one cultured with HUVECs in the vascular channels. The proposed blood vessel on a chip and the permeability measurement protocol have a significant potential to allow for the study of cavitation-enhanced permeability of the endothelium and improve efficiency in screening drug delivery systems.

  3. Vasculites dos médios e grandes vasos Medium and large vessel vasculitis

    Directory of Open Access Journals (Sweden)

    Hebert Roberto Clivati Brandt

    2009-02-01

    Full Text Available As vasculites são constituídas por um grande grupo de síndromes caracterizadas por inflamação e necrose da parede dos vasos sangüíneos, resultando em estreitamento ou oclusão do lúmen. A distribuição dos vasos envolvidos varia consideravelmente e serve de base para a classificação das síndromes vasculíticas: grandes vasos (arterite de Takayasu, arterite temporal; pequenos e médios vasos (poliarterite nodosa, síndrome de Churg-Strauss, granulomatose de Wegener, vasculites nas doenças reumáticas; e pequenos vasos (vasculite de hipersensibilidade, púrpura de Henoch-Schonlein, poliangeíte microscópica, crioglobulinemia. Este artigo revisa as vasculites dos médios e grandes vasos e opções terapêuticas atuais; além de oferecer orientação sobre abordagem diagnóstica e tratamento dos pacientes com suspeita de vasculite cutânea.Vasculitis comprises a broad group of syndromes characterized by inflammation and necrosis on the walls of blood vessels, resulting in narrowing or occlusion of the lumen. The distribution of involved blood vessel varies considerably and serves as the basis for one classification of vasculitic syndromes: large vessels (Takayasu arteritis, giant cell arteritis; medium and small muscular arteries (polyarteritis nodosa, Churg-Strauss syndrome, Wegener's granulomatosis, vasculitis in rheumatic diseases; and small vessels ("hypersensitivity" vasculitis, Henoch-Schonlein purpura, microscopic polyangiitis, cryoglobulinemia. This article reviews medium and large vessel vasculitis and current treatment options; it also presents a comprehensive approach to diagnosing and treating patients with suspected cutaneous vasculitis.

  4. Compressed sensing based simultaneous black- and gray-blood carotid vessel wall MR imaging.

    Science.gov (United States)

    Li, Bo; Li, Hao; Kong, Hanjing; Dong, Li; Zhang, Jue; Fang, Jing

    2017-05-01

    In this study, we sought to demonstrate the blood suppression performance, image quality and morphological measurements for compressed sensing (CS) based simultaneous 3D black- and gray-blood imaging sequence (CS-siBLAG) in carotid vessel wall MR imaging. Seven healthy volunteers and five patients were recruited. Healthy subjects underwent five CS-siBLAG scans with 1, 2, 3, 4 and 5-fold accelerations. Signal-to-tissue ratio (STR) and contrast-to-tissue ratio (CTR) were computed as the measures of flowing signal suppression performance and the image quality for black-blood imaging of the technique. Vessel lumen area (LA) and wall area (WA) were compared between fully sampled acquisition and each accelerated acquisition. Patients underwent three CS-siBLAG scans with 1, 3 and 5-fold accelerations as well as a 3D time of flight (3D TOF) scan. Two radiologists reviewed the under-sampled black- and gray-blood image quality. STR and CTR values obtained with 2 to 5-fold accelerations were not significantly different from those with full acquisition. LA and WA measured at 2×, 3×, 4× and 5× were all highly correlated to the corresponding values at 1×. For patients imaging, two radiologists both found that the dual-contrast images at 3× acceleration exhibited comparable image quality to that of the fully sampled acquisition, and that the images at 5× exhibited slightly blurred vessel wall and outer vessel wall boundaries. By combining the CS under-sampling pattern and reconstruction, pseudo-centric phase encoding order and dual blood contrast sequences, this technique provides spatially registered black- and gray-blood images and excellent visualization for vessel wall imaging and gray-blood imaging in a short scan time. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Retinal Vessel Diameters and Their Relationship with Cardiovascular Risk and All-Cause Mortality in the Inter99 Eye Study

    DEFF Research Database (Denmark)

    Drobnjak, Dragana; Munch, Inger Christine; Glümer, Charlotte

    2016-01-01

    equivalent (CRAE). Multiple linear regression analyses and Cox regression models were used. Results. Multiple linear regression analyses showed that narrower CRAE was associated with higher systolic blood pressure, age, and higher HDL cholesterol, whereas wider CRAE and CRVE were associated with smoking...

  6. Measuring vessel dimensions in oak wood (Quercus sp.) on macroscopic level with image analysis system - Lucia G

    OpenAIRE

    Merela, Maks; Oven, Primož; Čufar, Katarina

    2005-01-01

    System for image analysis Lucia G was used for measuring vessel dimensions of oak wood (Quercus sp.) on macroscopic level. We present the problem of sample preparation as well as capturing and processing of images for automatic measurements of diameters, areas and perimeters of early wood vessels. After testing various methods of sample preparation we found out that the best results were obtained when the samples were sanded with paper of granulation 320 and the surface stained with black alc...

  7. Design of vacuum vessel for Indian Test Facility (INTF) for 100 keV neutral beams

    International Nuclear Information System (INIS)

    Joshi, Jaydeep; Yadav, Ashish; Gangadharan, Roopesh; Prasad, Rambilas; Ulahannan, Shino; Rotti, Chandramouli; Bandyopadhyay, Mainak; Chakraborty, Arun

    2015-01-01

    Highlights: • Thickness calculation and optimization for the main shell, ducts, Dishends and top lid on the main shell. • Nozzle and flange design for the port openings. • Support structure design for the main shell and ducts. • FEA validation of the INTF vessel for operational, seismic and lifting condition. - Abstract: The Indian Test Facility (INTF) vacuum vessel is designed to install a full-scale test set-up of Diagnostic Neutral Beam (DNB) [1] for the qualification of beam parameters and the behavior of beam-line components prior to installation and operation in ITER. Vacuum vessel is designed in cylindrical shape having length of ∼9 m with diameter of ∼4.5 m and has a detachable top-lid for mounting as well as removal of internal components during installation and maintenance phases. The Vessel has hemispherical dish-ends with large openings for high-voltage bushing on one side and duct on another side. Vessel is provided with openings for hydraulic, cryo, gas-feed and diagnostics. Vessel duct is composed of three segments with length ranges from 3 m to 5 m with diameter of ∼1.5 m and one vessel at the end to house the second calorimeter. The objective of this paper is to present the design and analysis of vacuum vessel, with respect to its functional and operational requirements. The design calculations are done as per ASME-BPVC SectionVIII-Div.1 and subsequently Finite Element Analysis (FEM) method has been adopted to verify the design.

  8. Design of vacuum vessel for Indian Test Facility (INTF) for 100 keV neutral beams

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Jaydeep, E-mail: Jaydeep.joshi@iter-india.org [ITER-India, Institute for Plasma Research, A29, GIDC Electronics Estate, Gandhinagar 382016, Gujarat (India); Yadav, Ashish; Gangadharan, Roopesh [ITER-India, Institute for Plasma Research, A29, GIDC Electronics Estate, Gandhinagar 382016, Gujarat (India); Prasad, Rambilas [Madan Mohan Malaviya University of Technology, Gorakhpur, Uttar Pradesh 273001 (India); Ulahannan, Shino [Airframe Aerodesigns Pvt. Ltd., HAL Airport Exit Road, Old Airport Road, Bengaluru 17 (India); Rotti, Chandramouli; Bandyopadhyay, Mainak; Chakraborty, Arun [ITER-India, Institute for Plasma Research, A29, GIDC Electronics Estate, Gandhinagar 382016, Gujarat (India)

    2015-10-15

    Highlights: • Thickness calculation and optimization for the main shell, ducts, Dishends and top lid on the main shell. • Nozzle and flange design for the port openings. • Support structure design for the main shell and ducts. • FEA validation of the INTF vessel for operational, seismic and lifting condition. - Abstract: The Indian Test Facility (INTF) vacuum vessel is designed to install a full-scale test set-up of Diagnostic Neutral Beam (DNB) [1] for the qualification of beam parameters and the behavior of beam-line components prior to installation and operation in ITER. Vacuum vessel is designed in cylindrical shape having length of ∼9 m with diameter of ∼4.5 m and has a detachable top-lid for mounting as well as removal of internal components during installation and maintenance phases. The Vessel has hemispherical dish-ends with large openings for high-voltage bushing on one side and duct on another side. Vessel is provided with openings for hydraulic, cryo, gas-feed and diagnostics. Vessel duct is composed of three segments with length ranges from 3 m to 5 m with diameter of ∼1.5 m and one vessel at the end to house the second calorimeter. The objective of this paper is to present the design and analysis of vacuum vessel, with respect to its functional and operational requirements. The design calculations are done as per ASME-BPVC SectionVIII-Div.1 and subsequently Finite Element Analysis (FEM) method has been adopted to verify the design.

  9. Fast retinal vessel detection and measurement using wavelets and edge location refinement.

    Directory of Open Access Journals (Sweden)

    Peter Bankhead

    Full Text Available The relationship between changes in retinal vessel morphology and the onset and progression of diseases such as diabetes, hypertension and retinopathy of prematurity (ROP has been the subject of several large scale clinical studies. However, the difficulty of quantifying changes in retinal vessels in a sufficiently fast, accurate and repeatable manner has restricted the application of the insights gleaned from these studies to clinical practice. This paper presents a novel algorithm for the efficient detection and measurement of retinal vessels, which is general enough that it can be applied to both low and high resolution fundus photographs and fluorescein angiograms upon the adjustment of only a few intuitive parameters. Firstly, we describe the simple vessel segmentation strategy, formulated in the language of wavelets, that is used for fast vessel detection. When validated using a publicly available database of retinal images, this segmentation achieves a true positive rate of 70.27%, false positive rate of 2.83%, and accuracy score of 0.9371. Vessel edges are then more precisely localised using image profiles computed perpendicularly across a spline fit of each detected vessel centreline, so that both local and global changes in vessel diameter can be readily quantified. Using a second image database, we show that the diameters output by our algorithm display good agreement with the manual measurements made by three independent observers. We conclude that the improved speed and generality offered by our algorithm are achieved without sacrificing accuracy. The algorithm is implemented in MATLAB along with a graphical user interface, and we have made the source code freely available.

  10. Replacing a double-lumen tube with a single-lumen tube or a laryngeal mask airway device to reduce coughing at emergence after thoracic surgery: a randomized controlled single-blind trial.

    Science.gov (United States)

    Tanoubi, Issam; Sun, Joanna Ng Man; Drolet, Pierre; Fortier, Louis-Philippe; Donati, François

    2015-09-01

    Coughing episodes occur frequently at extubation after thoracic surgery, and this may be due in part to the double-lumen tube (DLT). In this study, the DLT was replaced with either a single-lumen endotracheal tube (ETT) or a laryngeal mask airway (LMA) device or left in place, and the incidence of coughing at emergence was compared between the three groups. Fifty-eight adults scheduled for thoracic surgery with a DLT were included. Exclusion criteria were an anticipated difficult airway, obesity, and contraindication to the use of an LMA ProSeal™ (LMA-P). After surgery but before emergence, patients were randomized to having the DLT (1) removed and replaced by an LMA-P (LMA-P Group), (2) removed and replaced by an ETT (ETT Group), or (3) left in place (DLT Group). The primary outcome was the number of coughing episodes at extubation. Among 184 patients screened, 124 did not meet inclusion criteria, and two patients, both in the ETT Group, were excluded after randomization, leaving 20, 18, and 20 patients in the LMA-P, ETT, and DLT Groups, respectively. There were fewer coughing episodes (median [quartiles]) in the LMA-P Group than in the DLT Group (0[0-1] vs 2[1-3], respectively; P = 0.01). In the DLT Group, 90% of patients coughed at least once. This incidence was not significantly different in the ETT Group (83%; P = 0.222) but was significantly reduced in the LMA-P Group (35%; P replaced by an LMA-P before emergence. The number of patients in this trial was too small to evaluate the risks associated with exchanging the airway device. This trial was registered at ClinicalTrials.gov: NCT00925613.

  11. Apparatus and method for examining a blood vessel of interest using radiation detected outside the body

    International Nuclear Information System (INIS)

    Shaw, R.F.

    1982-01-01

    Stenotic atherosclerotic lesions of the coronary arteries are detected by injecting a number of particulate signal sources such as positron-emitting particles (e.g. gallium 68) into the blood of a subject to determine the velocity of blood flow through the coronary vessels. The particles are tracked in three dimensions whenever they appear in the region of the heart by means of high-resolution high-speed gamma detectors that surround the chest. These recordings of particle position as a function of time are analyzed, and the velocity of blood as it flows through the coronary artery is measured by timing the transit of the particle. From the accumulated data of multiple particle transits through the coronary circulation, a three-dimensional representation of the lumen of the coronary arterial system is constructed

  12. AFSC/FMA/Vessel Assessment Logging

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Vessels fishing trawl gear, vessels fishing hook-and-line and pot gear that are also greater than 57.5 feet overall, and shoreside and floating processing facilities...

  13. 2013 EPA Vessels General Permit (VGP)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Information for any vessel that submitted a Notice of Intent (NOI), Notice of Termination (NOT), or annual report under EPA's 2013 Vessel General Permit (VGP)....

  14. Remission spectrometry for blood vessel detection during stereotactic biopsy of brain tumors.

    Science.gov (United States)

    Markwardt, Niklas A; Stepp, Herbert; Franz, Gerhard; Sroka, Ronald; Goetz, Marcus; Zelenkov, Petr; Rühm, Adrian

    2017-08-01

    Stereotactic biopsy is used to enable diagnostic confirmation of brain tumors and treatment planning. Despite being a well-established technique, it is related to significant morbidity and mortality rates mostly caused by hemorrhages due to blood vessel ruptures. This paper presents a method of vessel detection during stereotactic biopsy that can be easily implemented by integrating two side-view fibers into a conventional side-cutting biopsy needle. Tissue within the needle window is illuminated through the first fiber; the second fiber detects the remitted light. By taking the ratio of the intensities at two wavelengths with strongly differing hemoglobin absorption, blood vessels can be recognized immediately before biopsy sampling. Via ray tracing simulations and phantom experiments, the dependency of the remission ratio R = I 578 /I 650 on various parameters (blood oxygenation, fiber-to-vessel and inter-fiber distance, vessel diameter and orientation) was investigated for a bare-fiber probe. Up to 800-1200 µm away from the probe, a vessel can be recognized by a considerable reduction of the remission ratio from the background level. The technique was also successfully tested with a real biopsy needle probe on both optical phantoms and ex-vivo porcine brain tissue, thus showing potential to improve the safety of stereotactic biopsy. Dual-wavelength remission measurement for the detection of blood vessels during stereotactic biopsy. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Estimation of retinal vessel caliber using model fitting and random forests

    Science.gov (United States)

    Araújo, Teresa; Mendonça, Ana Maria; Campilho, Aurélio

    2017-03-01

    Retinal vessel caliber changes are associated with several major diseases, such as diabetes and hypertension. These caliber changes can be evaluated using eye fundus images. However, the clinical assessment is tiresome and prone to errors, motivating the development of automatic methods. An automatic method based on vessel crosssection intensity profile model fitting for the estimation of vessel caliber in retinal images is herein proposed. First, vessels are segmented from the image, vessel centerlines are detected and individual segments are extracted and smoothed. Intensity profiles are extracted perpendicularly to the vessel, and the profile lengths are determined. Then, model fitting is applied to the smoothed profiles. A novel parametric model (DoG-L7) is used, consisting on a Difference-of-Gaussians multiplied by a line which is able to describe profile asymmetry. Finally, the parameters of the best-fit model are used for determining the vessel width through regression using ensembles of bagged regression trees with random sampling of the predictors (random forests). The method is evaluated on the REVIEW public dataset. A precision close to the observers is achieved, outperforming other state-of-the-art methods. The method is robust and reliable for width estimation in images with pathologies and artifacts, with performance independent of the range of diameters.

  16. Atom-bond connectivity index and diameter of graphs

    Directory of Open Access Journals (Sweden)

    Lin WU

    2016-12-01

    Full Text Available For further study of the numerous nice properties of topological indices in physical and chemical fields, it is worth considering the relation between a degree-based index and a distance-based index. With the fact that diameter is an invariant based on distance, the relations between atom-bond connectivity index, diameter in trees and unicyclic graphs are studied. Based on relative lemma, the relation between atom-bond connectivity index and diameter in tree and unicyclic graphs is investigated, then the sharp lower bounds of the difference of index and diameter are given.

  17. Persistent left superior vena cava with thrombus formed in the catheter lumen 4 h after dialysis catheter placed.

    Science.gov (United States)

    Kawasaki, Tomoki; Tanaka, Hiroyuki; Oba, Miki; Takada, Megumi; Tanaka, Haruna; Suda, Shin

    2018-02-17

    Persistent left superior vena cava (PLSVC) is one of the most common thoracic venous anomaly and rarely noticed, because it is asymptomatic. However, for nephrologists, it is frequent enough to be encountered while placing hemodialysis catheters through the jugular vein. We report the case of 66-year-old patient with PLSVC presenting intrinsic thrombosis formation 4 h after dialysis catheter placed. Dialysis catheter was placed in the left internal jugular vein without resistance and any complication. PLSVC was detected after dialysis catheter insertion. We decided to remove the catheter, because the patient has other veins in which the catheter can be placed. When it was removed 4 h after catheter placing, thrombus was recognized in the catheter lumen. Transesophageal echocardiography was performed and no thrombus formation was observed in the heart chamber. For patients with PLSVC, if there were other veins in which the catheter can be placed, catheter replacement should be considered.

  18. Terlipressin increased the concentration of L-lactate in the rectal lumen in a patient with septic shock

    DEFF Research Database (Denmark)

    Perner, A; Jørgensen, V L; Waldau, T

    2004-01-01

    Terlipressin--a long-acting analogue of vasopressin--has been described to restore blood pressure in patients with catecholamine-resistant septic shock without obvious complications. We administered low-dose terlipressin (a single i.v.-bolus of 0.5 mg) to a patient with severe, hyperdynamic septic...... in this patient with noradrenalin-treated septic shock....... shock requiring high dosage of noradrenalin. After terlipressin the dose of noradrenalin could be reduced by 2/3 to obtain the same blood pressure. Two hours after terlipressin, the cardiac index had decreased from 6.2 to 3.3 l min(-1) m(-2) and the concentration of L-lactate in the rectal lumen...

  19. Academic Research Vessels 1985-1990.

    Science.gov (United States)

    1982-01-01

    replacement, and only one of these vessels was larger than 100 ft. In addition to the recently completed replacements of the EASTWARD and the GILLISS by... GILLISS and R/V EASTWARD by two new coastal vessels, the R/V CAPE FLORIDA and R/V CAPE HATTERAS. These estimates for the cost of vessel replacement

  20. 33 CFR 151.1512 - Vessel safety.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Vessel safety. 151.1512 Section... River § 151.1512 Vessel safety. Nothing in this subpart relieves the master of the responsibility for ensuring the safety and stability of the vessel or the safety of the crew and passengers, or any other...

  1. 50 CFR 300.125 - Vessel identification.

    Science.gov (United States)

    2010-10-01

    ... contrasting color to the background at least 18 inches (45.7 cm) in height for fishing vessels over 65 ft (19....125 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED ACTIVITIES INTERNATIONAL FISHERIES REGULATIONS Vessels of the United States Fishing in Colombian Treaty Waters § 300.125 Vessel identification...

  2. Reactor vessel supported by flexure member

    International Nuclear Information System (INIS)

    Crawford, J.D.; Pankow, B.

    1975-01-01

    A description is given of a reactor pressure vessel which is provided with vertical support means in the form of circumferentially spaced columns upon which the vessel is mounted. The columns are adapted to undergo flexure in order to accommodate the thermally induced displacements experienced by the vessel during operational transients

  3. Manufacturing technologies of PWR pressure vessels

    International Nuclear Information System (INIS)

    Qin Xubin

    1991-01-01

    Pressure vessels belong to the main component of PWR plants. Starting with describing the manufacture of pressure vessel components and their assembly, the manufacturing technologies of pressure vessels are briefly presented with regards to welding, heat treatment, inspections and testing. In addition, quality assurance during the manufacture is presented with emphasis

  4. Model tests for prestressed concrete pressure vessels

    International Nuclear Information System (INIS)

    Stoever, R.

    1975-01-01

    Investigations with models of reactor pressure vessels are used to check results of three dimensional calculation methods and to predict the behaviour of the prototype. Model tests with 1:50 elastic pressure vessel models and with a 1:5 prestressed concrete pressure vessel are described and experimental results are presented. (orig.) [de

  5. The Disruption of Vessel-Spanning Bubbles with Sloped Fins in Flat-Bottom and 2:1 Elliptical-Bottom Vessels

    Energy Technology Data Exchange (ETDEWEB)

    Gauglitz, Phillip A.; Buchmiller, William C.; Jenks, Jeromy WJ; Chun, Jaehun; Russell, Renee L.; Schmidt, Andrew J.; Mastor, Michael M.

    2010-09-22

    vessel with a sloped wall is that a small fin decreases the volume of a vessel available for sludge storage by a very small fraction compared to a cone-shaped vessel. The purpose of this study is to quantify the capability of sloped fins to disrupt VSBs and to conduct sufficient tests to estimate the performance of fins in full-scale STSCs. Experiments were conducted with a range of fin shapes to determine what slope and width were sufficient to disrupt VSBs. Additional tests were conducted to demonstrate how the fin performance scales with the sludge layer thickness and the sludge strength, density, and vessel diameter based on the gravity yield parameter, which is a dimensionless ratio of the force necessary to yield the sludge to its weight.( ) Further experiments evaluated the difference between vessels with flat and 2:1 elliptical bottoms and a number of different simulants, including the KW container sludge simulant (complete), which was developed to match actual K-Basin sludge. Testing was conducted in 5-in., 10-in., and 23-in.-diameter vessels to quantify how fin performance is impacted by the size of the test vessel. The most significant results for these scale-up tests are the trend in how behavior changes with vessel size and the results from the 23-in. vessel. The key objective in evaluating fin performance is to determine the conditions that minimize the volume of a VSB when disruption occurs because this reduces the potential for material inside the STSC from being released through vents.

  6. The Impact of Intimal Tear Location and Partial False Lumen Thrombosis in Acute Type B Aortic Dissection.

    Science.gov (United States)

    Girish, Apoorva; Padala, Muralidhar; Kalra, Kanika; McIver, Bryant V; Veeraswamy, Ravi K; Chen, Edward P; Leshnower, Bradley G

    2016-12-01

    Partial false lumen (FL) thrombosis is a risk factor for long-term mortality in acute type B aortic dissection (ATBAD). This study investigates FL pressures in models of ATBAD with patent and partially thrombosed FL. Twenty-five porcine aortas were used to create five models of ATBAD that were connected to a pulsatile flow loop. Models A through C had a patent FL with the following morphologies: model A, single proximal tear; model B, single distal tear; and model C, single proximal and single distal tear. Models D and E had a single proximal and a single distal tear, with partial FL thrombosis. Model D had FL occlusion of the proximal tear, and model D had FL occlusion of the distal tear. True lumen (TL) and FL pressures were measured at 90 to 150 mm Hg. In model A, FL pressures were 6 mm Hg higher than TL pressures (p < 0.01). In model B, FL pressures were 10 mm Hg lower than TL pressures (p ≤ 0.01). In model C, TL and FL pressures were equivalent. In model D, FL pressures were 40 mm Hg lower than TL pressures (p < 0.001). In model E, FL pressures were 10 mm Hg higher than TL pressures (p < 0.01). In a biologic model of ATBAD, the number, location, and FL thrombosis status determine FL pressure. In the setting of partial FL thrombosis, the FL pressure is reduced with proximal tear occlusion and increased with distal tear occlusion. Reduced FL pressure is related to retrograde flow. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  7. Clinical application of hysterosalpingography with a double-lumen catheter of a contrast media combination consisting iohexol and saline

    International Nuclear Information System (INIS)

    Xi Jiayuan; Jiang Yong; Cao Xinhua; Zhu Ying; Lv Liang; Zhao Xinxiang; Wei Dingying; Shao Jingxuan; Hua Jian

    2005-01-01

    Objective: To evaluate the clinical value of hysteosalpingographic diagnosis in infertile women. Methods: After a catheter with a double-lumen saccule was inserted into the uterine cavity, saline or air of 2.5-3.5 ml was injected to fill the saccule. The filled saccule was inserted at the isthmus of uterus for blocking the internal orifice. The contrast medium was injected through the catheter into the uterine cavity and fallopian tubes to undertake hysterosalpingography and fallopian tube reopening. In case of fallopian tube obstruction, the injection pressure could be increased to obtain recanalization. All operations and selective imagings were carried out under TV supervision. Results: 2698 cases including 806 primary infertile women and 1868 secondary infertile women were examined by this method. Technical success rate was 99.5% with 2198 cases (81.9%) having normal uterus, 249 (9.3%) congenital abnormal uterus and 238 (8.9%) uterus diseases. The number of obstructed fallopian tube was 3028 with 117 serious hydropsy (3.8%). Ninety-eight cases had been examined with lipiodol hysterosalpingography in other hospitals with 35 cases still having lipiodol accumulated within the uterine cavities and fallopian tubes. No serious complications or death occurred except slight pain. Conclusions: Double-lumen cather with a contrast media combination of iohexol and saline for hysterosal pinography is safe, easy and effective, outcoming with excellent quality images. More information can be gained with this method than traditional lipiodol hyterosalpinography, and furthermore could have compression during radiogrophy and avoid the long term stasis of lipiodol. (authors)

  8. Accuracy of High-Resolution MRI with Lumen Distention in Rectal Cancer Staging and Circumferential Margin Involvement Prediction

    International Nuclear Information System (INIS)

    Iannicelli, Elsa; Di Renzo, Sara; Ferri, Mario; Pilozzi, Emanuela; Di Girolamo, Marco; Sapori, Alessandra; Ziparo, Vincenzo; David, Vincenzo

    2014-01-01

    To evaluate the accuracy of magnetic resonance imaging (MRI) with lumen distention for rectal cancer staging and circumferential resection margin (CRM) involvement prediction. Seventy-three patients with primary rectal cancer underwent high-resolution MRI with a phased-array coil performed using 60-80 mL room air rectal distention, 1-3 weeks before surgery. MRI results were compared to postoperative histopathological findings. The overall MRI T staging accuracy was calculated. CRM involvement prediction and the N staging, the accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were assessed for each T stage. The agreement between MRI and histological results was assessed using weighted-kappa statistics. The overall MRI accuracy for T staging was 93.6% (k = 0.85). The accuracy, sensitivity, specificity, PPV and NPV for each T stage were as follows: 91.8%, 86.2%, 95.5%, 92.6% and 91.3% for the group ≤ T2; 90.4%, 94.6%, 86.1%, 87.5% and 94% for T3; 98,6%, 85.7%, 100%, 100% and 98.5% for T4, respectively. The predictive CRM accuracy was 94.5% (k = 0.86); the sensitivity, specificity, PPV and NPV were 89.5%, 96.3%, 89.5%, and 96.3% respectively. The N staging accuracy was 68.49% (k = 0.4). MRI performed with rectal lumen distention has proved to be an effective technique both for rectal cancer staging and involved CRM predicting

  9. The hindgut lumen prokaryotic microbiota of the termite Reticulitermes flavipes and its responses to dietary lignocellulose composition.

    Science.gov (United States)

    Boucias, Drion G; Cai, Yunpeng; Sun, Yijun; Lietze, Verena-Ulrike; Sen, Ruchira; Raychoudhury, Rhitoban; Scharf, Michael E

    2013-04-01

    Reticulitermes flavipes (Isoptera: Rhinotermitidae) is a highly eusocial insect that thrives on recalcitrant lignocellulosic diets through nutritional symbioses with gut-dwelling prokaryotes and eukaryotes. In the R. flavipes hindgut, there are up to 12 eukaryotic protozoan symbionts; the number of prokaryotic symbionts has been estimated in the hundreds. Despite its biological relevance, this diverse community, to date, has been investigated only by culture- and cloning-dependent methods. Moreover, it is unclear how termite gut microbiomes respond to diet changes and what roles they play in lignocellulose digestion. This study utilized high-throughput 454 pyrosequencing of 16S V5-V6 amplicons to sample the hindgut lumen prokaryotic microbiota of R. flavipes and to examine compositional changes in response to lignin-rich and lignin-poor cellulose diets after a 7-day feeding period. Of the ~475,000 high-quality reads that were obtained, 99.9% were annotated as bacteria and 0.11% as archaea. Major bacterial phyla included Spirochaetes (24.9%), Elusimicrobia (19.8%), Firmicutes (17.8%), Bacteroidetes (14.1%), Proteobacteria (11.4%), Fibrobacteres (5.8%), Verrucomicrobia (2.0%), Actinobacteria (1.4%) and Tenericutes (1.3%). The R. flavipes hindgut lumen prokaryotic microbiota was found to contain over 4761 species-level phylotypes. However, diet-dependent shifts were not statistically significant or uniform across colonies, suggesting significant environmental and/or host genetic impacts on colony-level microbiome composition. These results provide insights into termite gut microbiome diversity and suggest that (i) the prokaryotic gut microbiota is much more complex than previously estimated, and (ii) environment, founding reproductive pair effects and/or host genetics influence microbiome composition. © 2013 Blackwell Publishing Ltd.

  10. Accuracy of High-Resolution MRI with Lumen Distention in Rectal Cancer Staging and Circumferential Margin Involvement Prediction

    Energy Technology Data Exchange (ETDEWEB)

    Iannicelli, Elsa; Di Renzo, Sara [Radiology Institute, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant' Andrea Hospital, Rome 00189 (Italy); Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant' Andrea Hospital, Rome 00189 (Italy); Ferri, Mario [Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant' Andrea Hospital, Rome 00189 (Italy); Pilozzi, Emanuela [Department of Clinical and Molecular Sciences, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant' Andrea Hospital, Rome 00189 (Italy); Di Girolamo, Marco; Sapori, Alessandra [Radiology Institute, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant' Andrea Hospital, Rome 00189 (Italy); Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant' Andrea Hospital, Rome 00189 (Italy); Ziparo, Vincenzo [Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant' Andrea Hospital, Rome 00189 (Italy); David, Vincenzo [Radiology Institute, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant' Andrea Hospital, Rome 00189 (Italy); Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant' Andrea Hospital, Rome 00189 (Italy)

    2014-07-01

    To evaluate the accuracy of magnetic resonance imaging (MRI) with lumen distention for rectal cancer staging and circumferential resection margin (CRM) involvement prediction. Seventy-three patients with primary rectal cancer underwent high-resolution MRI with a phased-array coil performed using 60-80 mL room air rectal distention, 1-3 weeks before surgery. MRI results were compared to postoperative histopathological findings. The overall MRI T staging accuracy was calculated. CRM involvement prediction and the N staging, the accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were assessed for each T stage. The agreement between MRI and histological results was assessed using weighted-kappa statistics. The overall MRI accuracy for T staging was 93.6% (k = 0.85). The accuracy, sensitivity, specificity, PPV and NPV for each T stage were as follows: 91.8%, 86.2%, 95.5%, 92.6% and 91.3% for the group ≤ T2; 90.4%, 94.6%, 86.1%, 87.5% and 94% for T3; 98,6%, 85.7%, 100%, 100% and 98.5% for T4, respectively. The predictive CRM accuracy was 94.5% (k = 0.86); the sensitivity, specificity, PPV and NPV were 89.5%, 96.3%, 89.5%, and 96.3% respectively. The N staging accuracy was 68.49% (k = 0.4). MRI performed with rectal lumen distention has proved to be an effective technique both for rectal cancer staging and involved CRM predicting.

  11. ATLAS Supplier Award for the ECT Vacuum Vessels

    CERN Multimedia

    Jenni, P

    On 12 February the Netherlands firm Schelde Exotech was awarded the ATLAS Supplier Award for the construction of the two vacuum vessels for the ATLAS End- Cap Toroid (ECT) magnets. ATLAS Supplier Award ceremonies have now become something of a tradition. For the third consecutive year, ATLAS has given best supplier awards for the most exceptional contributors to the construction of the detector. The Netherlands firm Schelde Exotech has just received the award for the construction of the two vacuum vessels for the ECTs. With a diameter of 11 metres and a volume of 550 cubic metres, the ECT vacuum vessels are obviously impressive in scale. They consist of large aluminium plates and a stainless steel central bore tube. In order to obtain the required undulations, the firm had to develop a special assembly and welding technique. Despite the chambers' imposing size, a very high degree of precision has been achieved in their geometry. Moreover, the chambers, which were delivered in July 2002 to CERN, were built i...

  12. A posteriori-derived dietary patterns and retinal vessel caliber in an elderly population.

    Science.gov (United States)

    McEvoy, Claire T; Cardwell, Christopher R; Chakravarthy, Usha; Hogg, Ruth E; McKinley, Michelle C; Young, Ian S; Fletcher, Astrid E; Woodside, Jayne V

    2013-02-15

    To examine the association between a posteriori-derived dietary patterns (DP) and retinal vessel caliber in an elderly population. This was a cross-sectional study of 288 elderly adults (>65 years) who participated in the European Eye study (EUREYE) Northern Irish cohort. DP were extracted using principal component analysis from completed food frequency questionnaires. Semi-automated computer grading was used to determine the mean retinal vessel diameters (central retinal arteriole equivalent [CRAE] and central retinal venule equivalent [CRVE]) from digitized visual field one images using a standard measurement protocol. THREE MAJOR DP WERE IDENTIFIED IN THIS POPULATION, WHICH ACCOUNTED FOR 21% OF THE TOTAL VARIANCE: a "healthy" pattern with high factor loadings for oily fish, fruits and vegetables, and olive oil; an "unhealthy" pattern with high factor loadings for red and processed meat, refined grains, eggs, butter, sugar and sweets; and a "snack and beverage" pattern with high factor loading for pizza, nuts, and coffee. Multivariable linear regression analysis indicated no significant association between major identified DP and mean CRAE or CRVE in all models. This is the first study to investigate associations between a posteriori-derived DP and retinal vessel caliber. There was no evidence of a relationship between extracted DP and retinal vessel measurements in this population. However, it is possible that potentially important relationships exist between single nutrients or foods and vessel diameters that cannot be identified using a DP approach. Further studies to examine the role of dietary factors in the microcirculation are required.

  13. Vasodilator effects of ibudilast on retinal blood vessels in anesthetized rats.

    Science.gov (United States)

    Noguchi, Masahiro; Mori, Asami; Sakamoto, Kenji; Nakahara, Tsutomu; Ishii, Kunio

    2009-11-01

    Ibudilast (3-isobutyryl-2-isopropylpyrazolo[1,5-alpha]pyridine) is clinically used as a cerebral vasodilator in Japan. However, the effects of ibudilast on retinal blood vessels have not been fully examined. The aim of this study, therefore, was to examine the effects of ibudilast on retinal blood vessels in rats in vivo. Male Wistar rats (8 to 10 weeks old) were anesthetized with thiobutabarbital (120 mg/kg, intraperitoneally (i.p.)). Retinal vascular images were captured with a fundus camera system for small animals, and the diameter of retinal blood vessels was measured. Ibudilast (0.1 and 1 mg/kg, intravenously (i.v.)) elicited a sustained increase in the diameter of retinal blood vessels and heart rate without altering systemic blood pressure. The effects of ibudilast were significantly reduced by treatment with the nonselective cyclooxygenase inhibitor indomethacin (5 mg/kg, i.p.). These results suggest that ibudilast dilates retinal blood vessels through cyclooxygenase-dependent mechanisms in rats in vivo.

  14. Investigation of the relations between screw diameter and pilot hole diameter with withdrawal resistance in LVL for establishing regression model

    Directory of Open Access Journals (Sweden)

    mossayeb dalvand

    2018-02-01

    Full Text Available In this study, variation in screw diameter and corresponding pilot hole, and relationship between these variables with withdrawal resistance for establishing multiple linear regression model was investigated. In this investigation 9-ply LVL was made of poplar (Populus deltoids. LVL was produced with polyvinyl acetate adhesive. Test specimens were prepared from LVL produced with dimensions of 7.5 * 7.5 cm. Dimension of pilot hole embedded in specimens at 4 levels (50, 60, 70 and 80 present of nominal screw diameter. The test Specimens were studied with nominal screw diameter 4.2, 5, 6 and 7mm were produced. Withdrawal resistance of screw was tested from surface and, edge and cross-sections. Results have shown that withdrawal resistance from edge (perpendicular to grain was more than withdrawal resistance from face and cross-section (parallel to grain. Also the results have shown that withdrawal resistance of different screw diameter decreased with increase of pilot hole diameter, but withdrawal resistance increased with increase of screw diameter itself. The highest withdrawal resistance was obtained from screw 7 mm in diameters and predrilled hole diameter 50% of screw diameter. The lowest withdrawal resistance was observed from screw 4.2 mm in diameter and predrilled hole diameter 80% of screw diameter. Finally multiple linear regression models ys= 3.055+.411X1-3.358X2, ye║=2.6361.694X1+.089X2 and ye┴= 2.334+.509X1-2.901X2 were obtained to predict of withdrawal resistance for face, cross-section and edge respectively.

  15. Isotachophoresis system having larger-diameter channels flowing into channels with reduced diameter and with selectable counter-flow

    Energy Technology Data Exchange (ETDEWEB)

    Mariella, Jr., Raymond P.

    2018-03-06

    An isotachophoresis system for separating a sample containing particles into discrete packets including a flow channel, the flow channel having a large diameter section and a small diameter section; a negative electrode operably connected to the flow channel; a positive electrode operably connected to the flow channel; a leading carrier fluid in the flow channel; a trailing carrier fluid in the flow channel; and a control for separating the particles in the sample into discrete packets using the leading carrier fluid, the trailing carrier fluid, the large diameter section, and the small diameter section.

  16. Integrating Multiple Autonomous Underwater Vessels, Surface Vessels and Aircraft into Oceanographic Research Vessel Operations

    Science.gov (United States)

    McGillivary, P. A.; Borges de Sousa, J.; Martins, R.; Rajan, K.

    2012-12-01

    Autonomous platforms are increasingly used as components of Integrated Ocean Observing Systems and oceanographic research cruises. Systems deployed can include gliders or propeller-driven autonomous underwater vessels (AUVs), autonomous surface vessels (ASVs), and unmanned aircraft systems (UAS). Prior field campaigns have demonstrated successful communication, sensor data fusion and visualization for studies using gliders and AUVs. However, additional requirements exist for incorporating ASVs and UASs into ship operations. For these systems to be optimally integrated into research vessel data management and operational planning systems involves addressing three key issues: real-time field data availability, platform coordination, and data archiving for later analysis. A fleet of AUVs, ASVs and UAS deployed from a research vessel is best operated as a system integrated with the ship, provided communications among them can be sustained. For this purpose, Disruptive Tolerant Networking (DTN) software protocols for operation in communication-challenged environments help ensure reliable high-bandwidth communications. Additionally, system components need to have considerable onboard autonomy, namely adaptive sampling capabilities using their own onboard sensor data stream analysis. We discuss Oceanographic Decision Support System (ODSS) software currently used for situational awareness and planning onshore, and in the near future event detection and response will be coordinated among multiple vehicles. Results from recent field studies from oceanographic research vessels using AUVs, ASVs and UAS, including the Rapid Environmental Picture (REP-12) cruise, are presented describing methods and results for use of multi-vehicle communication and deliberative control networks, adaptive sampling with single and multiple platforms, issues relating to data management and archiving, and finally challenges that remain in addressing these technological issues. Significantly, the

  17. Sex Dimorphism of the Heart Diameters and Cardiothoracic Ratios ...

    African Journals Online (AJOL)

    Objective: To determine gender associated differences in the cardiothoracic ratio (CTR) and heart diameters in a normal Nigerian population. Subject and Method: The normal heart diameters and cardiothoracic ratios were measured from posteroanterior (PA) chest radiographs of healthy 510 male and 508 female ...

  18. Generalized height-diameter models for Populus tremula L. stands

    African Journals Online (AJOL)

    USER

    2010-07-12

    Jul 12, 2010 ... Using permanent sample plot data, selected tree height and diameter functions were evaluated for their predictive abilities for Populus tremula stands in Turkey. Two sets of models were evaluated. The first set included five models for estimating height as a function of individual tree diameter; the second set.

  19. Mean particle diameters : From statistical definition to physical understanding

    NARCIS (Netherlands)

    Alderliesten, M.

    2008-01-01

    Mean particle diameters are important for the science of particulate systems. This thesis deals with a definition system for these mean diameters, called Moment-Ratio (M-R) definition system, and provides a general statistical and physical basis. Also, the current DIN/ISO definition system is

  20. Growth process and diameter structure of Pinus tabulaeformis forest ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... Using stem analysis method, the biomass, growing process and diameter structure of 21-year shady and sunny slope Pinus tabulaeformis forest were investigated in hilly loess-gully region. Results showed that there were distinct difference in the indexes, tree height, diameter at breast height (DBH).

  1. Mean Normal Portal Vein Diameter Using Sonography among ...

    African Journals Online (AJOL)

    BACKGROUND: Mean portal vein diameter is considered as the best indicator for portal hypertension. However, the cutoff point differs from study to study (above 10-15 mm) despite the existence of normal mean portal vein diameter between 10-15 mm in different settings.This implies the existence of limited evidence on ...

  2. Growth process and diameter structure of Pinus tabulaeformis forest ...

    African Journals Online (AJOL)

    Using stem analysis method, the biomass, growing process and diameter structure of 21-year shady and sunny slope Pinus tabulaeformis forest were investigated in hilly loess-gully region. Results showed that there were distinct difference in the indexes, tree height, diameter at breast height (DBH) and timber volume ...

  3. Relationships between stem diameter at breast height (DBH), tree ...

    African Journals Online (AJOL)

    Trees show considerable variation and flexibility in their size of crowns, height and stem diameter at breast height (dbh). Dbh has been used as predictor variables in diameter and height growth equations. Relationships between dbh, tree height, crown length, crown height and crown ratio of Vitellaria paradoxa were ...

  4. Generalized height-diameter models for Populus tremula L. stands ...

    African Journals Online (AJOL)

    On average, by including stand level attributes, root mean square values were reduced by 21 cm. In the second set, the best results were obtained by the Schnute's function. In this function, dominant diameter and dominant height independent variables in addition to tree diameter were found significant at 0.01 significant ...

  5. Relationships between diameter and height of trees in natural ...

    African Journals Online (AJOL)

    Relationships between diameter and height of trees in natural tropical forest in Tanzania. Wilson A Mugasha, Ole M Bollandsås, Tron Eid. Abstract. The relationship between tree height (h) and tree diameter at breast height (dbh) is an important element describing forest stands. In addition, h often is a required variable in ...

  6. Influence of high intensity ultrasound with different probe diameter ...

    African Journals Online (AJOL)

    The main goal of this research is to analyze the influence of ultrasonic probe diameters (7 and 10 mm) of high-intensity ultrasound with constant frequency (30 kHz) on the degree of homogenization (variance) of cow milk. Influence of different probe diameters on the physical properties of cow milk was also tested. Changes ...

  7. Semi-automated tracking and continuous monitoring of inferior vena cava diameter in simulated and experimental ultrasound imaging.

    Science.gov (United States)

    Mesin, Luca; Pasquero, Paolo; Albani, Stefano; Porta, Massimo; Roatta, Silvestro

    2015-03-01

    Assessment of respirophasic fluctuations in the diameter of the inferior vena cava (IVC) is detrimentally affected by its concomitant displacements. This study was aimed at presenting and validating a method to compensate for IVC movement artifacts while continuously measuring IVC diameter in an automated fashion (with minimal interaction with the user) from a longitudinal B-mode ultrasound clip. Performance was tested on both experimental ultrasound clips collected from four healthy patients and simulations, implementing rigid IVC displacements and pulsation. Compared with traditional M-mode measurements, the new approach systematically reduced errors in caval index assessment (range over maximum diameter value) to an extent depending on individual vessel geometry, IVC movement and choice of the M-line (the line along which the diameter is computed). In experimental recordings, this approach identified both the cardiac and respiratory components of IVC movement and pulsatility and evidenced the spatial dependence of IVC pulsatility. IVC tracking appears to be a promising approach to reduce movement artifacts and to improve the reliability of IVC diameter monitoring. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  8. Study of fluid dynamics reveals direct communications between lymphatic vessels and venous blood vessels at lymph nodes of mice.

    Science.gov (United States)

    Takeda, Kazu; Mori, Shiro; Kodama, Tetsuya

    2017-06-01

    Cancer cells metastasize to lymph nodes, with distant metastasis resulting in poor prognosis. The role of lymph node metastasis (LNM) in the spread of cancer to distant organs remain incompletely characterized. The visualization of flow dynamics in the lymphatic and blood vessels of MXH10/Mo-lpr/lpr mice, which develop systemic swelling of lymph nodes up to 10mm in diameter, has revealed that lymph nodes have the potential to be a direct source of systemic metastasis. However, it is not known whether these fluid dynamics characteristics are universal phenomena present in other strains of laboratory mice. Here we show that the fluid dynamics observed in MXH10/Mo-lpr/lpr mice are the same as those observed in C57BL/6J, BALB/cAJcl and NOD/ShiJic-scidJcl mice. Furthermore, when fluorescent solution was injected into a tumor-bearing lymph node, the flow dynamics observed in the efferent lymphatic vessels and thoracoepigastric vein depended on the type of tumor cell. Our results indicate that fluid dynamics in the lymphatic and blood vessels of MXH10/Mo-lpr/lpr mice are generalized phenomena seen in conventional laboratory mice. We anticipate our results can facilitate studies of the progression of lymphatic metastasis to hematogenous metastasis via lymph nodes and the early diagnosis and treatment of LNM. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Rates of chemical reaction and atmospheric heating during core debris expulsion from a pressurized vessel

    International Nuclear Information System (INIS)

    Powers, D.A.; Tarbell, W.W.; Brockman, J.E.; Pilch, M.

    1986-01-01

    Core debris may be expelled from a pressurized reactor vessel during a severe nuclear reactor accident. Experimental studies of core debris expulsion from pressurized vessels have established that the expelled material can be lofted into the atmosphere of the reactor containment as particulate 0.4 to 2 mm in diameter. These particles will vigorously react with steam and oxygen in the containment atmosphere. Data on such reactions during tests with 80 kg of expelled melt will be reported. A model of the reaction rates based on gas phase mass transport will be described and shown to account for atmospheric heating and aerosol generation observed in the tests

  10. Vessel for storing and disposing radioactive waste

    International Nuclear Information System (INIS)

    Takakura, Masahide.

    1997-01-01

    A vessel for storing and disposing radioactive wastes is composed of a containing vessel main body having an opening and a lid capable of fitting with the opening. The containing vessel main body is made into a cylindrical shape which can contain radioactive wastes therein. The containing vessel main body and the lid are made of a reinforced material such as carbon steels and stainless steels respectively. A plurality of fin set up-seats are disposed, each at a same distance, detachably to the outer surface of the containing vessel main body in parallel with the axial line of the containing vessel main body. Heat dissipating fins are secured on the outer surface of the fin set-up-seats. With such a constitution, there can be obtained a vessel suitable to underground disposal of radioactive wastes after cooling and storing them till removal of after heat. (I.N.)

  11. Diameter of common bile duct: what are the predicting factors?

    Directory of Open Access Journals (Sweden)

    Atoosa Adibi

    2007-07-01

    Full Text Available

    BACKGROUND: This was a study to determine the correlation between the common bile duct (CBD diameter and demographic data, fasting, and the history of opium addiction.
    METHODS: This was a cross-sectional study on 375 patients (>16 years old including 219 females and 156 males. They had no evident hepatobiliary or pancreatic disease and underwent abdominopelvic ultrasonography for measurement of their CBD diameter. Ultrasound (US was performed to measure CBD diameter at the porta hepatis (proximal part and behind the head of the pancreas (distal part. Correlation coefficients for the association between CBD diameter and predictive factors were calculated. t-test was applied to compare the means between the groups.
    RESULTS: The mean CBD diameter (1 standard deviation, in proximal and distal parts were 3.64 mm (±1.2 and 3.72 mm (±1.2, respectively. The CBD diameters (proximal and distal were significantly (P<0.05 correlated with age (r = 0.55 and 0.54, respectively, BMI (r = 0.25 and 0.27, respectively and portal vein diameter (r = 0.24 and 0.22, respectively. Distal diameter of CBD was significantly larger in opium addicts (5.66 ± 2.65 in comparison with non addicts (3.68 ± 1.17, P = 0.04.
    CONCLUSIONS: CBD diameter associates with age, BMI, portal vein diameter and opium addiction. CBD dilatation, if it can not be explained by age, opium usage or large BMI, should be evaluated further to rule out obstruction.
    KEY WORDS: Common bile duct, predicting factors, ultrasonography.

  12. Relation of Coronary Artery Diameters With Cardiorespiratory Fitness.

    Science.gov (United States)

    Ho, John S; Cannaday, John J; FitzGerald, Shannon J; Leonard, David; Finley, Carrie E; Wade, Wendy A; Reinhardt, Dale B; Ellis, Joe R; Barlow, Carolyn E; Haskell, William L; Defina, Laura F; Gibbons, Larry W; Cooper, Kenneth H

    2018-02-06

    Cardiorespiratory fitness is associated with reduced cardiovascular morbidity and mortality when adjusted for traditional risk factors. Mechanisms by which fitness reduces risk have been studied but remain incompletely understood. We hypothesize that higher fitness is associated with larger coronary artery diameters independent of its effect on traditional risk factors. Two independent measurements of the proximal diameters of the left main, left anterior descending, left circumflex, and right coronary arteries were obtained from gated multidetector computed tomography scans in 500 men from the Cooper Center Longitudinal Study (CCLS). Men with coronary artery calcium scores ≥10 were excluded. Fitness was measured with a maximal exercise treadmill test and reported by quintiles and as a function of METs. We then evaluated the relation between coronary artery diameters and fitness using mixed effect regression models. Higher fitness was associated with larger coronary artery diameters after adjustment for body surface area, smoking status, low-density lipoprotein and high-density lipoprotein cholesterol, resting systolic blood pressure, and serum glucose. When examined continuously, each MET increase in fitness was associated with a mean 0.03 ± 0.01 mm larger diameter of the left main, a 0.04 ± 0.01 mm larger diameter of the left anterior descending, a 0.05 ± 0.01 mm larger diameter of the left circumflex, and a 0.07 ± 0.01 mm larger diameter of the right coronary artery (p = 0.002). This correlation between fitness and coronary artery diameters was most prominent for fitness levels above 10 METs. In conclusion, higher fitness is associated with larger coronary artery diameters. Copyright © 2018 Elsevier Inc. All rights reserved.

  13. New aspects of MRI for diagnostics of large vessel vasculitis and primary angiitis of the central nervous system

    International Nuclear Information System (INIS)

    Saam, T.; Habs, M.; Cyran, C.C.; Grimm, J.; Reiser, M.F.; Nikolaou, K.; Pfefferkorn, T.; Schueller, U.

    2010-01-01

    Vasculitis is a rare disease and clinical symptoms are often unspecific. Accurate and early diagnosis is mandatory in order to prevent complications, such as loss of vision or stroke. Imaging techniques can contribute to establishing a definite diagnosis and to evaluate disease activity and the extent of the disease in various vascular regions. Conventional imaging methods, such as computed tomography (CT) and magnetic resonance (MR) angiography, as well as digital subtraction angiography allow the vessel lumen but not the vessel wall to be depicted. However, vasculitis is a disease which primarily affects the vessel wall, therefore conventional imaging modalities often fail to make a definite diagnosis. Recently black-blood high resolution MR in vivo imaging has been used to visualize cervical and intracranial vasculitis. This review article presents imaging protocols for intracranial and cervical black-blood MR imaging and clinical cases with large vessel vasculitis and vasculitis of the central nervous system. Furthermore the current literature, examples of the most common differential diagnoses of cervical and cranial arteriopathy and the potential of other imaging modalities, such as PET/CT and ultrasound will be discussed. (orig.) [de

  14. What is cerebral small vessel disease?

    International Nuclear Information System (INIS)

    Onodera, Osamu

    2011-01-01

    An accumulating amount of evidence suggests that the white matter hyperintensities on T 2 weighted brain magnetic resonance imaging predict an increased risk of dementia and gait disturbance. This state has been proposed as cerebral small vessel disease, including leukoaraiosis, Binswanger's disease, lacunar stroke and cerebral microbleeds. However, the concept of cerebral small vessel disease is still obscure. To understand the cerebral small vessel disease, the precise structure and function of cerebral small vessels must be clarified. Cerebral small vessels include several different arteries which have different anatomical structures and functions. Important functions of the cerebral small vessels are blood-brain barrier and perivasucular drainage of interstitial fluid from the brain parenchyma. Cerebral capillaries and glial endfeet, take an important role for these functions. However, the previous pathological investigations on cerebral small vessels have focused on larger arteries than capillaries. Therefore little is known about the pathology of capillaries in small vessel disease. The recent discoveries of genes which cause the cerebral small vessel disease indicate that the cerebral small vessel diseases are caused by a distinct molecular mechanism. One of the pathological findings in hereditary cerebral small vessel disease is the loss of smooth muscle cells, which is an also well-recognized finding in sporadic cerebral small vessel disease. Since pericytes have similar character with the smooth muscle cells, the pericytes should be investigated in these disorders. In addition, the loss of smooth muscle cells may result in dysfunction of drainage of interstitial fluid from capillaries. The precise correlation between the loss of smooth muscle cells and white matter disease is still unknown. However, the function that is specific to cerebral small vessel may be associated with the pathogenesis of cerebral small vessel disease. (author)

  15. Drug-eluting stents vs bare metal stents for the treatment of large coronary vessels.

    Science.gov (United States)

    Quizhpe, Arturo R; Feres, Fausto; de Ribamar Costa, José; Abizaid, Alexandre; Maldonado, Galo; Costa, Ricardo; Abizaid, Andrea; Cano, Manuel; Moreira, Adriana C; Staico, Rodolfo; Mattos, Luiz Alberto; Tanajura, Luiz Fernando; Chaves, Aurea; Centemero, Marinella; Sousa, Amanda M R; Sousa, J Eduardo M R

    2007-08-01

    Lately drug-eluting stents (DES) have dramatically reduced restenosis rates and need for repeat revascularization in a wide subset of lesion and patients. However, their benefit for the treatment of large vessels (> 3.0 mm) has yet to be established. We investigated whether DES are superior to bare metal stents (BMS) in terms of clinical outcomes for the treatment of large coronary vessels. This study assessed the long-term outcomes (cardiac death, acute myocardial infarction, and need for repeat intervention in the treated vessel) of patients treated with either a DES (Cypher and Taxus) or a BMS of > or = 3.5 mm in diameter. A total of 250 consecutive patients who underwent DES implantation were clinically followed for 1 year and compared to 250 patients who were treated with BMS. Interventions in the setting of acute ST elevation myocardial infarction and treatment of bypass grafts were excluded. Cypher was the DES deployed in 70.8% of cases. Most of the enrolled patients were men (78%) with single vessel disease (65.6%). The left anterior descending artery was the culprit vessel in 34.2% of cases. Bare metal stent and DES cohorts had equivalent interpolated reference vessel diameter (3.19 +/- 0.3 mm for BMS vs 3.18 +/- 0.2 for DES; P = .1). Lesion was significantly longer in the group treated with DES (13.4 +/- 5.1 mm for BMS group vs 14.3 +/- 3.5 for DES; P = .0018). After 1 year of clinical follow-up, 95.2% of patients treated with DES and 91.2% of the patients who received BMS were free of major events (P = .2). A trend toward higher target-lesion revascularization was noticed in the group treated with BMS (4.8% vs 1.6%; P = .07). Percutaneous treatment of large coronary vessels carries a low risk of clinical events irrespective of the type of stent used.

  16. Rapid sealing of porcine renal blood vessels, ex vivo, using a high power, 1470-nm laser, and laparoscopic prototype

    Science.gov (United States)

    Hardy, Luke A.; Hutchens, Thomas C.; Larson, Eric R.; Gonzalez, David A.; Chang, Chun-Hung; Nau, William H.; Fried, Nathaniel M.

    2017-05-01

    Energy-based, radiofrequency (RF) and ultrasonic (US) devices currently provide rapid sealing of blood vessels during laparoscopic procedures. We are exploring infrared lasers as an alternate energy modality for vessel sealing, capable of generating less collateral thermal damage. Previous studies demonstrated feasibility of sealing vessels in an in vivo porcine model using a 1470-nm laser. However, the initial prototype was designed for testing in open surgery and featured tissue clasping and light delivery mechanisms incompatible with laparoscopic surgery. In this study, a laparoscopic prototype similar to devices currently in surgical use was developed, and performance tests were conducted on porcine renal blood vessels, ex vivo. The 5-mm outer-diameter laparoscopic prototype featured a traditional Maryland jaw configuration that enables tissue manipulation and blunt dissection. Laser energy was delivered through a 550-μm-core-diameter optical fiber with side-delivery from the lower jaw and beam dimensions of 18-mm length×1.2-mm width. The 1470-nm diode laser delivered 68 W with 3-s activation time, consistent with vessel seal times associated with RF and US-based devices. A total of 69 fresh porcine renal vessels with mean diameter of 3.3±1.7 mm were tested, ex vivo. Vessels smaller than 5-mm diameter were consistently sealed (48/51) with burst pressures greater than malignant hypertension blood pressure (180 mmHg), averaging 1038±474 mmHg. Vessels larger than 5 mm were not consistently sealed (6/18), yielding burst pressures of only 174±221 mmHg. Seal width, thermal damage zone, and thermal spread averaged 1.7±0.8, 3.4±0.7, and 1.0±0.4 mm, respectively. Results demonstrated that the 5-mm optical laparoscopic prototype consistently sealed vessels less than 5-mm diameter with low thermal spread. Further in vivo studies are planned to test the performance across a variety of vessels and tissues.

  17. Progress of ITER vacuum vessel

    Energy Technology Data Exchange (ETDEWEB)

    Ioki, K., E-mail: Kimihiro.Ioki@iter.org [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Bayon, A. [F4E, c/ Josep Pla, No. 2, Torres Diagonal Litoral, Edificio B3, E-08019 Barcelona (Spain); Choi, C.H.; Daly, E.; Dani, S.; Davis, J.; Giraud, B.; Gribov, Y.; Hamlyn-Harris, C.; Jun, C.; Levesy, B. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Kim, B.C. [NFRI, 52 Yeoeundong Yuseonggu, Daejeon 305-333 (Korea, Republic of); Kuzmin, E. [NTC “Sintez”, Efremov Inst., 189631 Metallostroy, St. Petersburg (Russian Federation); Le Barbier, R.; Martinez, J.-M. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Pathak, H. [ITER-India, A-29, GIDC Electronic Estate, Sector 25, Gandhinagar 382025 (India); Preble, J. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Sa, J.W. [NFRI, 52 Yeoeundong Yuseonggu, Daejeon 305-333 (Korea, Republic of); Terasawa, A.; Utin, Yu. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); and others

    2013-10-15

    Highlights: ► This covers the overall status and progress of the ITER vacuum vessel activities. ► It includes design, R and D, manufacturing and approval process of the regulators. ► The baseline design was completed and now manufacturing designs are on-going. ► R and D includes ISI, dynamic test of keys and lip-seal welding/cutting technology. ► The VV suppliers produced full-scale mock-ups and started VV manufacturing. -- Abstract: Design modifications were implemented in the vacuum vessel (VV) baseline design in 2011–2012 for finalization. The modifications are mostly due to interface components, such as support rails and feedthroughs for the in-vessel coils (IVC). Manufacturing designs are being developed at the domestic agencies (DAs) based on the baseline design. The VV support design was also finalized and tests on scale mock-ups are under preparation. Design of the in-wall shielding (IWS) has progressed, considering the assembly methods and the required tolerances. Further modifications are required to be consistent with the DAs’ manufacturing designs. Dynamic tests on the inter-modular and stub keys to support the blanket modules are being performed to measure the dynamic amplification factor (DAF). An in-service inspection (ISI) plan has been developed and R and D was launched for ISI. Conceptual design of the VV instrumentation has been developed. The VV baseline design was approved by the agreed notified body (ANB) in accordance with the French Nuclear Pressure Equipment Order procedure.

  18. Progress of ITER vacuum vessel

    International Nuclear Information System (INIS)

    Ioki, K.; Bayon, A.; Choi, C.H.; Daly, E.; Dani, S.; Davis, J.; Giraud, B.; Gribov, Y.; Hamlyn-Harris, C.; Jun, C.; Levesy, B.; Kim, B.C.; Kuzmin, E.; Le Barbier, R.; Martinez, J.-M.; Pathak, H.; Preble, J.; Sa, J.W.; Terasawa, A.; Utin, Yu.

    2013-01-01

    Highlights: ► This covers the overall status and progress of the ITER vacuum vessel activities. ► It includes design, R and D, manufacturing and approval process of the regulators. ► The baseline design was completed and now manufacturing designs are on-going. ► R and D includes ISI, dynamic test of keys and lip-seal welding/cutting technology. ► The VV suppliers produced full-scale mock-ups and started VV manufacturing. -- Abstract: Design modifications were implemented in the vacuum vessel (VV) baseline design in 2011–2012 for finalization. The modifications are mostly due to interface components, such as support rails and feedthroughs for the in-vessel coils (IVC). Manufacturing designs are being developed at the domestic agencies (DAs) based on the baseline design. The VV support design was also finalized and tests on scale mock-ups are under preparation. Design of the in-wall shielding (IWS) has progressed, considering the assembly methods and the required tolerances. Further modifications are required to be consistent with the DAs’ manufacturing designs. Dynamic tests on the inter-modular and stub keys to support the blanket modules are being performed to measure the dynamic amplification factor (DAF). An in-service inspection (ISI) plan has been developed and R and D was launched for ISI. Conceptual design of the VV instrumentation has been developed. The VV baseline design was approved by the agreed notified body (ANB) in accordance with the French Nuclear Pressure Equipment Order procedure

  19. Influence of spacing on the survival, frequency of diameter classes and height/diameter ratio in Eucalyptus urophylla. [In Portuguese

    Energy Technology Data Exchange (ETDEWEB)

    Brandi, R.M.; Couto, L.; Neto, F. de P.

    1977-01-01

    Survival of hybrid (unspecified parentage) E. urophylla in Minas Gerais after 93 months ranged from 47.1% at a spacing of 2 x 2 m to 60.5% at 3 x 4 m. Close spacing gave the largest number of trees per unit area, but with smaller average diameter Height/diameter ratio was not influenced by spacing.

  20. Reactor pressure vessel vented head

    Science.gov (United States)

    Sawabe, James K.

    1994-01-11

    A head for closing a nuclear reactor pressure vessel shell includes an arcuate dome having an integral head flange which includes a mating surface for sealingly mating with the shell upon assembly therewith. The head flange includes an internal passage extending therethrough with a first port being disposed on the head mating surface. A vent line includes a proximal end disposed in flow communication with the head internal passage, and a distal end disposed in flow communication with the inside of the dome for channeling a fluid therethrough. The vent line is fixedly joined to the dome and is carried therewith when the head is assembled to and disassembled from the shell.

  1. The Heart and Great Vessels

    Science.gov (United States)

    Onwuka, Ekene; King, Nakesha; Heuer, Eric; Breuer, Christopher

    2018-01-01

    Cardiovascular disease is the leading cause of mortality worldwide. We have made large strides over the past few decades in management, but definitive therapeutic options to address this health-care burden are still limited. Given the ever-increasing need, much effort has been spent creating engineered tissue to replaced diseased tissue. This article gives a general overview of this work as it pertains to the development of great vessels, myocardium, and heart valves. In each area, we focus on currently studied methods, limitations, and areas for future study. PMID:28289246

  2. Effects of Bothrops asper snake venom on lymphatic vessels: insights into a hidden aspect of envenomation.

    Science.gov (United States)

    Mora, Javier; Mora, Rodrigo; Lomonte, Bruno; Gutiérrez, José María

    2008-01-01

    Envenomations by the snake Bothrops asper represent a serious medical problem in Central America and parts of South America. These envenomations concur with drastic local tissue pathology, including a prominent edema. Since lymph flow plays a role in the maintenance of tissue fluid balance, the effect of B. asper venom on collecting lymphatic vessels was studied. B. asper venom was applied to mouse mesentery, and the effects were studied using an intravital microscopy methodology coupled with an image analysis program. B. asper venom induced a dose-dependent contraction of collecting lymphatic vessels, resulting in a reduction of their lumen and in a halting of lymph flow. The effect was reproduced by a myotoxic phospholipase A(2) (PLA(2)) homologue isolated from this venom, but not by a hemorrhagic metalloproteinase or a coagulant thrombin-like serine proteinase. In agreement with this, treatment of the venom with fucoidan, a myotoxin inhibitor, abrogated the effect, whereas no inhibition was observed after incubation with the peptidomimetic metalloproteinase inhibitor Batimastat. Moreover, fucoidan significantly reduced venom-induced footpad edema. The myotoxic PLA(2) homologue, known to induce skeletal muscle necrosis, was able to induce cytotoxicity in smooth muscle cells in culture and to promote an increment in the permeability to propidium iodide in these cells. Our observations indicate that B. asper venom affects collecting lymphatic vessels through the action of myotoxic PLA(2)s on the smooth muscle of these vessels, inducing cell contraction and irreversible cell damage. This activity may play an important role in the pathogenesis of the pronounced local edema characteristic of viperid snakebite envenomation, as well as in the systemic biodistribution of the venom, thus representing a potential therapeutical target in these envenomations.

  3. Effects of Bothrops asper snake venom on lymphatic vessels: insights into a hidden aspect of envenomation.

    Directory of Open Access Journals (Sweden)

    Javier Mora

    Full Text Available Envenomations by the snake Bothrops asper represent a serious medical problem in Central America and parts of South America. These envenomations concur with drastic local tissue pathology, including a prominent edema. Since lymph flow plays a role in the maintenance of tissue fluid balance, the effect of B. asper venom on collecting lymphatic vessels was studied.B. asper venom was applied to mouse mesentery, and the effects were studied using an intravital microscopy methodology coupled with an image analysis program. B. asper venom induced a dose-dependent contraction of collecting lymphatic vessels, resulting in a reduction of their lumen and in a halting of lymph flow. The effect was reproduced by a myotoxic phospholipase A(2 (PLA(2 homologue isolated from this venom, but not by a hemorrhagic metalloproteinase or a coagulant thrombin-like serine proteinase. In agreement with this, treatment of the venom with fucoidan, a myotoxin inhibitor, abrogated the effect, whereas no inhibition was observed after incubation with the peptidomimetic metalloproteinase inhibitor Batimastat. Moreover, fucoidan significantly reduced venom-induced footpad edema. The myotoxic PLA(2 homologue, known to induce skeletal muscle necrosis, was able to induce cytotoxicity in smooth muscle cells in culture and to promote an increment in the permeability to propidium iodide in these cells.Our observations indicate that B. asper venom affects collecting lymphatic vessels through the action of myotoxic PLA(2s on the smooth muscle of these vessels, inducing cell contraction and irreversible cell damage. This activity may play an important role in the pathogenesis of the pronounced local edema characteristic of viperid snakebite envenomation, as well as in the systemic biodistribution of the venom, thus representing a potential therapeutical target in these envenomations.

  4. Diameter dependent electron transfer kinetics in semiconductor-enzyme complexes.

    Science.gov (United States)

    Brown, Katherine A; Song, Qing; Mulder, David W; King, Paul W

    2014-10-28

    Excited state electron transfer (ET) is a fundamental step for the catalytic conversion of solar energy into chemical energy. To understand the properties controlling ET between photoexcited nanoparticles and catalysts, the ET kinetics were measured for solution-phase complexes of CdTe quantum dots and Clostridium acetobutylicum [FeFe]-hydrogenase I (CaI) using time-resolved photoluminescence spectroscopy. Over a 2.0-3.5 nm diameter range of CdTe nanoparticles, the observed ET rate (kET) was sensitive to CaI concentration. To account for diameter effects on CaI binding, a Langmuir isotherm and two geometric binding models were created to estimate maximal CaI affinities and coverages at saturating concentrations. Normalizing the ET kinetics to CaI surface coverage for each CdTe diameter led to k(ET) values that were insensitive to diameter, despite a decrease in the free energy for photoexcited ET (ΔGET) with increasing diameter. The turnover frequency (TOF) of CaI in CdTe-CaI complexes was measured at several molar ratios. Normalization for diameter-dependent changes in CaI coverage showed an increase in TOF with diameter. These results suggest that k(ET) and H2 production for CdTe-CaI complexes are not strictly controlled by ΔG(ET) and that other factors must be considered.

  5. The Relationship amongst Intervertebral Disc Vertical Diameter, Lateral Foramen Diameter and Nerve Root Impingement in Lumbar Vertebra

    Directory of Open Access Journals (Sweden)

    Yusof MI

    2018-03-01

    Full Text Available Introduction: The vertical diameter of the foramen is dependent upon the vertical diameter of the corresponding intervertebral disc. A decrease in disc vertical diameter has direct anatomic consequences to the foraminal diameter and area available for the nerve root passing through it. This study is to establish the relationship amongst the intervertebral disc vertical diameter, lateral foramen diameters and nerve root compression in the lumbar vertebra. Materials and Methods: Measurements of the study parameters were performed using sagittal MRI images. The parameters studied were: intervertebral disc vertical diameter (DVD, foraminal vertical diameter (FVD, foraminal transverse diameter (FTD and nerve root diameter (NRD of both sides. The relationship between the measured parameters were then analyzed. Results: A total of 62 MRI images were available for this study. Statistical analysis showed moderate to strong correlation between DVD and FVD at all the lumbar levels except at left L23 and L5S1 and right L3L4 and L4L5. Correlation between DVD and FTD were not significant at all lumbar levels. Regression analysis showed that a decrease of 1mm of DVD was associated with 1.3, 1.7, 3.3, 3.3 and 1.3mm reduction of FVD at L1L2, L2L3, L3L4, L4L5 and L5S1 respectively. Conclusion: Reduction of DVD was associated with reduction of FVD. However, FVD was relatively wide for the nerve root even with complete loss of DVD. FTD was much narrower than the FVD making it more likely to cause nerve root compression at the exit foramina. These anatomical details should be given consideration in treating patients with lateral canal stenosis.

  6. Efficiency, efficacy, and safety of EZ-blocker compared with left-sided double-lumen tube for one-lung ventilation

    NARCIS (Netherlands)

    Mourisse, J.M.; Liesveld, J.; Verhagen, A.F.T.M.; Rooij, G. van; Heide, S. van der; Schuurbiers, O.C.J.; Heijden, E. van der

    2013-01-01

    BACKGROUND: Double-lumen tubes (DLTs) or bronchial blockers are commonly used for one-lung ventilation. DLTs are sometimes difficult or even impossible to introduce, and the incidence of postoperative hoarseness and airway injuries is higher. Bronchial blockers are more difficult to position and

  7. CALiPER Report 20.4: Lumen and Chromaticity Maintenance of LED PAR38 Lamps Operated in Steady-State Conditions

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-12-30

    This CALiPER report focuses on lumen maintenance, chromaticity maintenance, and catastrophic failure in 32 of the Series 20 LED PAR38 lamps and 8 benchmark lamps, which were monitored for nearly 14,000 hours at ambient temperatures between 44°C and 45°C.

  8. Comparison of coronary arterial lumen dimensions on angiography and plaque characteristics on optical coherence tomography images and their changes induced by statin

    International Nuclear Information System (INIS)

    Dong, Nana; Xie, Zulong; Wang, Wei; Dai, Jiannan; Sun, Meng; Pu, Zhongyue; Tian, Jinwei; Yu, Bo

    2016-01-01

    Coronary angiography (CAG) is widely used to assess lumen dimensions, and optical coherence tomography (OCT) is used to evaluate the characteristics of atherosclerotic plaque. This study was aimed to compare coronary lumen dimensions using CAG and plaque characteristics using OCT and their changes during statin therapy. We identified 97 lipid-rich plaques from 69 statin-naïve patients, who received statin therapy in the following 12 months. CAG and OCT examinations were conducted at baseline and 12-month follow-up period. Lesion length, as measured by CAG, was closely correlated with lipid length by OCT (baseline: r = 0.754, p < 0.001; follow-up: r = 0.639, p < 0.001). However, no significant correlations were found between the other findings on OCT and data on CAG. With 12-month statin therapy, microstructures of lipid-rich plaques were significantly improved, but CAG-derived lumen dimensions were not improved. Moreover, we found no significant relationship between changes in OCT measurements and changes in CAG data over time. Lipid length on OCT and lesion length on CAG were closely correlated. However, plaque microstructural characteristics on OCT showed no significantly statistically correlations with lumen dimensions on CAG, neither did their evolutionary changes induced by statin over time. Clinical trial registry: ClinicalTrial.gov. Registered number: NCT01023607. Registered 1 December 2009

  9. Preliminary experiment with a newly developed double balloon, double lumen catheter for extracorporeal life support vascular access.

    Science.gov (United States)

    Okamoto, Taisuke; Ichinose, Keisuke; Tanimoto, Hironari; Yoshitake, Atsushi; Sakanashi, Yuji; Tashiro, Masafumi; Terasaki, Hidenori

    2003-01-01

    Recently, venovenous extracorporeal life support (VVECLS) using a double lumen catheter has been clinically used to avoid neurologic complications in the treatment of respiratory failure for neonates. However, recirculation, which is a limiting factor for oxygen delivery, still exists, and thus it does not contribute to oxygenation of the patient. We developed a newly designed double lumen catheter with a double balloon (DBDL) catheter for ECLS vascular access and performed two animal preliminary experiments in normal and hypoxic dog models (normal ventilation and one lung ventilation experiments) to investigate whether the DBDL catheter could prevent recirculation and maintain oxygen delivery to systemic circulation. The DBDL catheter (JCT Co., Hiroshima, Japan) of 15 Fr was fabricated from silicone. It consists of two lumens for drainage and return of blood with two balloons (distal and proximal balloons) that prevent oxygenated blood mixing with unoxygenated blood. VVECLS using a DBDL catheter was performed in 13 mongrel dogs (8 dogs for normal ventilation experiment weighing 12.9 +/- 1.6 kg [mean +/- SD], 5 dogs for one lung ventilation experiment weighing 16.6 +/- 2.5 kg [mean +/- SD]) under anesthesia in the two experiments. The bypass flow ranged from 10-40 ml/kg per minute in the normal ventilation experiment. VVECLS in the one lung ventilation experiment was performed with maximal bypass flow for 6 hours (ranged from 25.2 +/- 8.0-28.3 +/- 8.7 ml/kg per minute at balloon inflation and deflation). Recirculation and oxygen transfer of artificial lung with or without balloon inflation during VVECLS were studied. Recirculation decreased with balloon inflation at varied bypass flows during VVECLS in the normal ventilation experiment (varied from 1.5 +/- 14.6-12.8 +/- 16.7%) and for 6 hours after VVECLS initiation in the one lung ventilation experiment (varied from 12.2 +/- 12.2-19.2 +/- 6.5%). In particular, the values at 3 and 6 hours were significantly lower

  10. Calibration of the radiometric asteroid scale using occultation diameters

    Science.gov (United States)

    Brown, R. H.; Morrison, D.; Telesco, C. M.; Brunk, W. E.

    1982-10-01

    The paper describes a new approach to the calibration of the radiometric asteroid scale, which relies on recent accurate occultation measurements of the diameters of 2 Pallas (Wasserman et al., 1979) and 3 Juno (Millis et al., 1981), and the Voyager diameter of J4 Callisto, as well as IR photometry of these objects obtained with the NASA 3-m Infrared Telescope Facility. It is shown that this calibration is internally consistent to better than 5%, and probably has an absolute accuracy of + or - 5%. It is noted that a revision of the TRIAD radiometric diameters downward is required to bring them into agreement with the new calibration.

  11. Development and Performance of a Thin Membrane Scintillator Containment Vessel for a Solar Neutrino Detector

    Science.gov (United States)

    Vogelaar, R. B.; Benziger, J. B.; Calaprice, F. P.; Chen, M.; Darnton, N.; Johnson, M.; Loeser, F.

    1996-10-01

    The Borexino solar neutrino experiment will detect neutrino-electron scattering interactions in a large mass (300 tons) of an organic solvent-based liquid scintillator. Requirements for the scintillator containment vessel include optical clarity, chemical resistance to the scintillator, ultra-low radioactivity and mechanical strength. These requirements are met in a thin membrane design utilizing a nylon copolymer C38F, manufactured by the Miles-Mobay Corporation. For the Borexino Counting Test Facility, a 2 meter diameter nylon sphere was constructed and used. Its performance will be discussed and the status of the development of an 8.5 meter diameter sphere for the Borexino detector will be presented.

  12. The lumenal loop M672-P707 of the Menkes protein (ATP7A) transfers copper to peptidylglycine monooxygenase

    Energy Technology Data Exchange (ETDEWEB)

    Otoikhian, Adenike [Oregon Health & Sciences University; Barry, Amanda N. [Los Alamos National Laboratory; Mayfield, Mary [Oregon Health & Science University; Nilges, Mark [Illinois EPR Center; Huang, Yiping [Johns Hopkins University; Lutsenko, Svetlana [Johns Hopkins University; Blackburn, Ninian [Oregon Health & Science University

    2012-05-14

    Copper transfer to cuproproteins located in vesicular compartments of the secretory pathway depends on activity of the copper translocating ATPase (ATP7A or ATP7B) but the mechanism of transfer is largely unexplored. Copper-ATPase ATP7A is unique in having a sequence rich in histidine and methionine residues located on the lumenal side of the membrane. The corresponding fragment binds Cu(I) when expressed as a chimera with a scaffold protein, and mutations or deletions of His and/or Met residues in its sequence inhibit dephosphorylation of the ATPase, a catalytic step associated with copper release. Here we present evidence for a potential role of this lumenal region of ATP7A in copper transfer to cuproenzymes. Both Cu(II) and Cu(I) forms were investigated since the form in which copper is transferred to acceptor proteins is currently unknown. Analysis of Cu(II) using EPR demonstrated that at Cu:P ratios below 1:1, 15N-substituted protein had Cu(II) bound by 4 His residues, but this coordination changed as the Cu(II) to protein ratio increased towards 2:1. XAS confirmed this coordination via analysis of the intensity of outer-shell scattering from imidazole residues. The Cu(II) complexes could be reduced to their Cu(I) counterparts by ascorbate, but here again, as shown by EXAFS and XANES spectroscopy, the coordination was dependent on copper loading. At low copper Cu(I) was bound by a mixed ligand set of His + Met while at higher ratios His coordination predominated. The copper-loaded loop was able to transfer either Cu(II) or Cu(I) to peptidylglycine monooxygenase in the presence of chelating resin, generating catalytically active enzyme in a process that appeared to involve direct interaction between the two partners. The variation of coordination with copper loading suggests copper-dependent conformational change which in turn could act as a signal for regulating copper release by the ATPase pump.

  13. Protection of thylakoids against combined light and drought by a lumenal substance in the resurrection plant Haberlea rhodopensis

    Science.gov (United States)

    Georgieva, Katya; Sárvári, Éva; Keresztes, Áron

    2010-01-01

    Background and Aims Haberlea rhodopensis is a perennial, herbaceous, saxicolous, poikilohydric flowering plant that is able to survive desiccation to air-dried state under irradiance below 30 µmol m−2 s−1. However, desiccation at irradiance of 350 µmol m−2 s−1 induced irreversible changes in the photosynthetic apparatus, and mature leaves did not recover after rehydration. The aim here was to establish the causes and mechanisms of irreversible damage of the photosynthetic apparatus due to dehydration at high irradiance, and to elucidate the mechanisms determining recovery. Methods Changes in chloroplast structure, CO2 assimilation, chlorophyll fluorescence parameters, fluorescence imaging and the polypeptide patterns during desiccation of Haberlea under medium (100 µmol m−2 s−1; ML) irradiance were compared with those under low (30 µmol m−2 s−1; LL) irradiance. Key Results Well-watered plants (control) at 100 µmol m−2 s−1 were not damaged. Plants desiccated at LL or ML had similar rates of water loss. Dehydration at ML decreased the quantum efficiency of photosystem II photochemistry, and particularly the CO2 assimilation rate, more rapidly than at LL. Dehydration induced accumulation of stress proteins in leaves under both LL and ML. Photosynthetic activity and polypeptide composition were completely restored in LL plants after 1 week of rehydration, but changes persisted under ML conditions. Electron microscopy of structural changes in the chloroplast showed that the thylakoid lumen is filled with an electron-dense substance (dense luminal substance, DLS), while the thylakoid membranes are lightly stained. Upon dehydration and rehydration the DLS thinned and disappeared, the time course largely depending on the illumination: whereas DLS persisted during desiccation and started to disappear during late recovery under LL, it disappeared from the onset of dehydration and later was completely lost under ML. Conclusions Accumulation of DLS

  14. Using perforators as recipient vessels (supermicrosurgery) for free flap reconstruction of the knee region.

    Science.gov (United States)

    Hong, Joon Pio; Koshima, Isao

    2010-03-01

    The purpose of this article is to evaluate the feasibility of a perforator as a recipient vessel to reconstruct soft tissue defects of the knee region.From December of 2006 to August of 2008, total of 25 patients underwent reconstructive procedure using either an anterolateral thigh or an upper medial thigh perforator flap. The flaps were anastomosed in a perforator to perforator manner using supermicrosurgery technique.Minimum of 3 perforators were traced around the knee defect. All flaps survived attached to a recipient perforator with artery diameter ranging from 0.4 to 0.9 mm and accompanying veins ranging from 0.4 to 1.2 mm. This approach allowed reduction in time for pedicle and recipient vessel dissection and minimized the trauma involved during isolation of the vessels.Using the perforator as recipient vessel allows an increase in selection for choice of recipient. By using a perforator as recipient, less time is consumed to secure the vessel, does not need long pedicles for flap, is not bound by the condition of major arteries, and minimizes any risk for major vessel injury while having acceptable flap survival.

  15. Comparative analysis of methods for extracting vessel network on breast MRI images

    Science.gov (United States)

    Gaizer, Bence T.; Vassiou, Katerina G.; Lavdas, Eleftherios; Arvanitis, Dimitrios L.; Fezoulidis, Ioannis V.; Glotsos, Dimitris T.

    2017-11-01

    Digital processing of MRI images aims to provide an automatized diagnostic evaluation of regular health screenings. Cancerous lesions are proven to cause an alteration in the vessel structure of the diseased organ. Currently there are several methods used for extraction of the vessel network in order to quantify its properties. In this work MRI images (Signa HDx 3.0T, GE Healthcare, courtesy of University Hospital of Larissa) of 30 female breasts were subjected to three different vessel extraction algorithms to determine the location of their vascular network. The first method is an experiment to build a graph over known points of the vessel network; the second algorithm aims to determine the direction and diameter of vessels at these points; the third approach is a seed growing algorithm, spreading selection to neighbors of the known vessel pixels. The possibilities shown by the different methods were analyzed, and quantitative measurements were performed. The data provided by these measurements showed no clear correlation with the presence or malignancy of tumors, based on the radiological diagnosis of skilled physicians.

  16. Evaluation of the normal thoracic and abdominal aorta diameters by computerized tomography; Avaliacao dos diametros normais da aorta toracica e abdominal pela tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Lucarelli, Claudio Luiz

    1995-07-01

    The study was undertaken to evaluate, through computerized tomography, the diameters of the normal thoracic and abdominal aorta, as well as they are connected to gender, age and body surface area; and the ratio between measurements obtained at the ascending and descending limbs of the thoracic aorta, and between the abdominal aortic diameters. For that reason, we measured the widest anteroposterior diameters of the thoracic aortas at the levels of the arch, the root, the pulmonary artery, and the thoracic-abdominal transition, as well as the level of the emergence of the superior mesenteric artery, of the renal hila and just cephalad to the bifurcation of the abdominal aortas of 350 patients without cardiovascular diseases who had undergone computerized tomography of the thorax and/or abdomen for any other reasons. Observation and statistic analyses led us to conclude that: 1) both the thoracic and abdominal aortic diameters are reduced from their proximal to their distal portions; 2) the body surface influences the size of the aorta, although only extreme variations alter the vessel's caliber; 3) vessel diameter was observed to gradually increase with age; 4) men were found to have larger diameters than age matched women; 5) the ratio between the ascending and descending aortic diameters varies according to gender and age; 6) the relations between abdominal aortic diameters measured at the level of renal hila and cephalad to the bifurcation are independent from gender and age. But the relation between those measured at the level of the superior mesenteric artery and cephalad to the bifurcation are linked to gender, but not to age. (author)

  17. Experimental vitrification of human compacted morulae and early blastocysts using fine diameter plastic micropipettes.

    Science.gov (United States)

    Cremades, N; Sousa, M; Silva, J; Viana, P; Sousa, S; Oliveira, C; Teixeira da Silva, J; Barros, A

    2004-02-01

    Vitrification of human blastocysts has been successfully applied using grids, straws and cryoloops. We assessed the survival rate of human compacted morulae and early blastocysts vitrified in pipette tips with a smaller inner diameter and solution volume than the previously described open pulled straw (OPS) method. Excess day 5 human embryos (n = 63) were experimentally vitrified in vessels. Embryos were incubated at 37 degrees C with sperm preparation medium (SPM) for 1 min, SPM + 7.5% ethylene glycol (EG)/dimethylsulphoxide (DMSO) for 3 min, and SPM + 16.5% EG + 16.5% DMSO + 0.67 mol/l sucrose for 25 s. They were then aspirated (0.5 microl) into a plastic micropipette tip (0.36 mm inner diameter), exposed to liquid nitrogen (LN(2)) vapour for 2 min before being placed into a pre-cooled cryotube, which was then closed and plunged into LN(2). Embryos were warmed and diluted using 0.33 mol/l and 0.2 mol/l sucrose. The survival rate for compacted morulae was 73% (22/30) and 82% (27/33) for early blastocysts. The survival rates of human compacted morulae and early blastocysts after vitrification with this simple technique are similar to those reported in the literature achieved by slow cooling and other vitrification protocols.

  18. A Strategy for Rapid Construction of Blood Vessel-Like Structures with Complex Cell Alignments.

    Science.gov (United States)

    Wang, Nuoxin; Peng, Yunhu; Zheng, Wenfu; Tang, Lixue; Cheng, Shiyu; Yang, Junchuan; Liu, Shaoqin; Zhang, Wei; Jiang, Xingyu

    2018-04-17

    A method is developed that can rapidly produce blood vessel-like structures by bonding cell-laden electrospinning (ES) films layer by layer using fibrin glue within 90 min. This strategy allows control of cell type, cell orientation, and material composition in separate layers. Furthermore, ES films with thicker fibers (polylactic-co-glycolic acid, fiber diameter: ≈3.7 µm) are used as cell-seeding layers to facilitate the cell in-growth; those with thinner fibers (polylactic acid, fiber diameter: ≈1.8 µm) are used as outer reinforcing layers to improve the mechanical strength and reduce the liquid leakage of the scaffold. Cells grow, proliferate, and migrate well in the multilayered structure. This design aims at a new type of blood vessel substitute with flexible control of parameters and implementation of functions. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Tests of the geometrical description of blood vessels in a thermal model using counter-current geometries

    NARCIS (Netherlands)

    van Leeuwen, G. M.; Kotte, A. N.; Crezee, J.; Lagendijk, J. J.

    1997-01-01

    We have developed a thermal model, for use in hyperthermia treatment planning, in which blood vessels are described as geometrical objects; 3D curves with associated diameters. For the calculation of the heat exchange with the tissue an analytic result is used. To arrive at this result some

  20. Improved Design Basis for Laterally Loaded Large Diameter Pile

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    in dry sand by use of centrifuge modelling and to compare the findings with the standard p-y curves. It has been chosen to apply piles with an embedment length of 6 to 10 times the diameter of the applied piles. The general static behaviour of monopiles in dry sand has based on centrifuge tests been...... initial response and a higher ultimate capacity. The initial stiffness of the soil-structure interaction measured in the centrifuge tests, equivalent to initial stiffness of p-y curves, shows a dependency of depth and diameter. Control issues in relation to cyclic tests have resulted in tests...... on the structure and the productivity of the turbine. Current design practice for monopiles are based on p-y curves developed for slender piles with a diameter of 0.6 m. The focus on the structure stiffness has entailed a significant research on the soil-structure interaction for large diameter monopiles...